Tricine and citric acid lipids

[0001] This application is a 35 U.S.C. § 371 National Stage Application of International Application No. PCT/US20/38822, filed on Jun. 19, 2020, which claims priority to U.S. Provisional Application Ser. No. 62/864,818, filed on Jun. 21, 2019, the entire disclosure of which is hereby incorporated by reference.

[0002] Delivery of nucleic acids has been explored extensively as a potential therapeutic option for certain disease states. In particular, messenger RNA (mRNA) therapy has become an increasingly important option for treatment of various diseases, including for those associated with deficiency of one or more proteins.

[0003] The present invention provides, among other things, cationic lipids useful in for delivery of mRNA. Delivery of mRNA provided by cationic lipids described herein can result in targeted delivery, reduce administration frequency, improve patient tolerability, and provide more potent and less toxic mRNA therapy for the treatment of a variety of diseases, including but not limited to cancer, cardiovascular, cystic fibrosis, infectious, and neurological diseases.

[0004] In a first aspect, the present invention provides new cationic lipids.

[0005] In a second aspect, the present invention provides a liposome encapsulating an mRNA encoding a protein wherein the liposome comprises one or more cationic lipids, one or more non-cationic lipids, one or more cholesterol-based lipids and one or more PEG-modified lipids, wherein at least one cationic lipid is a cationic lipid as described herein.

[0006] In a third aspect, the present invention provides a nucleic acid encapsulated within a liposome, wherein the liposome comprises a cationic lipid that is a cationic lipid as described herein.

[0007] In embodiments, a cationic lipid has a structure according to Formula (A):

[0008]
or a pharmaceutically acceptable salt thereof, wherein

• • [0009] each n is independently 0 or 1;
  • [0010] X^1A is independently O or NR^1A;
  • [0011] R^1A is H or C₁-C₆ alkyl;
  • [0012] X^1B is a covalent bond, C(O), CH₂CO₂, or CH₂C(O);
  • [0013] one of X^2A and X^2B is O and the other is a covalent bond;
  • [0014] one of X^3A and X^3B is O and the other is a covalent bond;
  • [0015] one of X^4A and X^4B is O and the other is a covalent bond;
  • [0016] R¹ is independently L¹-B¹, C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl;
  • [0017] R² is independently L²-B², C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl;
  • [0018] R³ is independently L³-B³, C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl;
  • [0019] R⁴ is independently L⁴-B⁴, C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl;
  • [0020] L¹, L², L³, and L⁴ are each independently C₁-C₃₀ alkylene; C₂-C₃₀ alkenylene; or C₂-C₃₀ alkynylene;
  • [0021] each of B¹, B², B³, and B⁴ is independently an ionizable nitrogen-containing group,
  • [0022] and
  • [0023] wherein the cationic lipid comprises at least one ionizable nitrogen-containing group.

[0024] In embodiments, a cationic lipid has a structure according to Formula (I),

[0025]

• • [0026] or a pharmaceutically acceptable salt thereof, wherein
  • [0027] each of R², R³, and R⁴ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl; and
  • [0028] L¹ is C₁-C₁₀ alkylene.

[0029] In embodiments, a cationic lipid has a structure according to Formula (I),

[0030]

• • [0031] or a pharmaceutically acceptable salt thereof, wherein
  • [0032] B¹ is an ionizable nitrogen-containing group;
  • [0033] each of R², R³, and R⁴ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl; and
  • [0034] L¹ is C₁-C₁₀ alkylene.

[0035] In embodiments, a cationic lipid has a structure according to Formula (II),

[0036]

• • [0037] or a pharmaceutically acceptable salt thereof, wherein
  • [0038] each of R², R³, and R⁴ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl; and
  • [0039] L¹ is C₁-C₁₀ alkylene.

[0040] In embodiments, a cationic lipid has a structure according to Formula (II),

[0041]

• • [0042] or a pharmaceutically acceptable salt thereof, wherein
  • [0043] R^1A is H or C₁-C₆ alkyl;
  • [0044] B¹ is an ionizable nitrogen-containing group;
  • [0045] each of R², R³, and R⁴ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl; and
  • [0046] L¹ is C₁-C₁₀ alkylene.

[0047] In embodiments, a cationic lipid has a structure according to Formula (AI),

[0048]

• • [0049] or a pharmaceutically acceptable salt thereof, wherein
  • [0050] L¹ is C₁-C₁₀ alkylene;
  • [0051] each R^6A is independently H or C₁-C₆ alkyl; and
  • [0052] each R^6B is independently H or C₁-C₆ alkyl.

[0053] In embodiments, a cationic lipid has a structure according to Formula (AII),

[0054]

[0055] or a pharmaceutically acceptable salt thereof.

[0056] In embodiments, a cationic lipid has a structure according to Formula (AIII),

[0057]

• • [0058] or a pharmaceutically acceptable salt thereof, wherein
  • [0059] R^1A is H.

[0060] In embodiments, a cationic lipid has a structure according to Formula (IIa),

[0061]

• • [0062] or a pharmaceutically acceptable salt thereof, wherein
  • [0063] B¹ is an ionizable nitrogen-containing group;
  • [0064] R^1A is H or C(O)—R⁷;
  • [0065] each of R², R³, R⁴, and R⁷ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl; and
  • [0066] L¹ is C₁-C₁₀ alkylene.

[0067] In embodiments, the cationic lipid has a structure according to Formula (IIb),

[0068]

• • [0069] or a pharmaceutically acceptable salt thereof, wherein
  • [0070] B¹ is an ionizable nitrogen-containing group;
  • [0071] R^1A is H or C(O)—R⁷; and
  • [0072] each of R², R³, R⁴, and R⁷ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0073] In embodiments, the cationic lipid has a structure according to Formula (IIc),

[0074]

• • [0075] or a pharmaceutically acceptable salt thereof, wherein
  • [0076] B¹ is an ionizable nitrogen-containing group; and
  • [0077] each of R², R³, R⁴, and R⁷ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0078] In embodiments, a cationic lipid has a structure according to Formula (IId),

[0079]

• • [0080] or a pharmaceutically acceptable salt thereof, wherein
  • [0081] B¹ is an ionizable nitrogen-containing group; and
  • [0082] each of R², R³, R⁴, and R⁷ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0083] In embodiments, R^1A is H.

[0084] In embodiments, L¹ is unsubstituted C₁-C₁₀ alkylene.

[0085] In embodiments, L¹ is (CH₂)₂, (CH₂)₃, (CH₂)₄, or (CH₂)₅.

[0086] In embodiments, B¹ is independently NH₂, guanidine, amidine, a mono- or dialkylamine, 5- to 6-membered nitrogen-containing heterocycloalkyl, or 5- to 6-membered nitrogen-containing heteroaryl.

[0087] In embodiments, B¹ is independently

[0088]

[0089] In embodiments, B¹ is independently

[0090]

[0091] In embodiments, each of R², R³, R⁴ and R⁷ is independently C₈H₁₇, C₁₀H₂₁, C₁₂H₂₅, C₁₄H₂₉, C₁₆H₃₃, C₁₆H₃₁, C₁₆H₂₉ and C₁₆H₃₂.

[0092] In embodiments, each of R², R³, R⁴ and R⁷ is independently C₆-C₂₂ alkyl, C₆-C₂₂ alkenyl, or C₆-C₂₂ alkynyl.

[0093] In embodiments, each of R², R³, R⁴ and R⁷ is independently C₆-C₂₂ alkyl, or C₆-C₂₂ alkenyl.

[0094] In embodiments, each of R², R³, R⁴ and R⁷ is independently unsubstituted linear C₆-C₂₂ alkyl, or unsubstituted linear C₆-C₂₂ alkenyl.

[0095] In embodiments, R¹ is independently C₈H₁₇, C₁₀H₂₁, C₁₂H₂₅, C₁₄H₂₉, C₁₆H₃₃, C₁₆H₃₁, C₁₆H₂₉ and C₁₆H₃₂.

[0096] In embodiments, R¹ is independently unsubstituted linear C₆-C₂₂ alkyl, unsubstituted linear C₆-C₂₂ alkenyl, or unsubstituted linear C₆-C₂₂ alkynyl.

[0097] In embodiments, each of R², R³, and R⁴ is independently unsubstituted linear C₆-C₂₂ alkyl, unsubstituted linear C₆-C₂₂ alkenyl, unsubstituted linear C₆-C₂₂ alkynyl, unsubstituted branched C₆-C₂₂ alkyl, unsubstituted branched C₆-C₂₂ alkenyl, or unsubstituted branched C₆-C₂₂ alkynyl.

[0098] In embodiments, each of R², R³, and R⁴ is unsubstituted C₆-C₂₂ alkyl.

[0099] In embodiments, each of R², R³, and R⁴ is independently C₆-C₁₂ alkyl substituted by —O(CO)R⁵ or —C(O)OR⁵, wherein R⁵ is unsubstituted C₆-C₁₄ alkyl.

[0100] In embodiments, each of R², R³, and R⁴ is unsubstituted C₆-C₂₂ alkenyl. In embodiments, said C₆-C₂₂ alkenyl is a monoalkenyl, a dienyl, or a trienyl.

[0101] In embodiments, each of R², R³, and R⁴ is

[0102]

[0103] In embodiments, each of R², R³, and R⁴ is

[0104]

[0105] In embodiments (e.g., of Formula (II)), each of R², R³, and R⁴ is

[0106]

[0107] In embodiments (e.g., of Formula (II)) each of R², R³, and R⁴ is

[0108]

[0109] In embodiments, a cationic lipid has a structure according to Formula (III),

[0110]
or a pharmaceutically acceptable salt thereof, wherein

• • [0111] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0112] In embodiments, a cationic lipid has a structure according to Formula (III),

[0113]
or a pharmaceutically acceptable salt thereof, wherein

• • [0114] L², L³, and L⁴ are each independently C₁-C₃₀ alkylene; C₂-C₃₀ alkenylene; or C₂-C₃₀ alkynylene;
  • [0115] each of B², B³, and B⁴ is independently an ionizable nitrogen-containing group; and
  • [0116] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0117] In embodiments, a cationic lipid has a structure according to Formula (IV),

[0118]
or a pharmaceutically acceptable salt thereof, wherein

• • [0119] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0120] In embodiments, a cationic lipid has a structure according to Formula (IV),

[0121]
or a pharmaceutically acceptable salt thereof, wherein

• • [0122] L², L³, and L⁴ are each independently C₁-C₃₀ alkylene; C₂-C₃₀ alkenylene; or C₂-C₃₀ alkynylene;
  • [0123] each of B², B³, and B⁴ is independently an ionizable nitrogen-containing group;
  • [0124] R^1A is H or C₁-C₆ alkyl; and
  • [0125] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0126] In embodiments, R^1A is H.

[0127] In embodiments, a cationic lipid has a structure according to Formula (V),

[0128]
or a pharmaceutically acceptable salt thereof, wherein

• • [0129] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0130] In embodiments, a cationic lipid has a structure according to Formula (V),

[0131]
or a pharmaceutically acceptable salt thereof, wherein

• • [0132] L², L³, and L⁴ are each independently C₁-C₃₀ alkylene; C₂-C₃₀ alkenylene; or C₂-C₃₀ alkynylene;
  • [0133] each of B², B³, and B⁴ is independently an ionizable nitrogen-containing group; and
  • [0134] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0135] In embodiments, a cationic lipid has a structure according to Formula (VI),

[0136]
or a pharmaceutically acceptable salt thereof, wherein

• • [0137] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0138] In embodiments, a cationic lipid has a structure according to Formula (VI),

[0139]
or a pharmaceutically acceptable salt thereof, wherein

• • [0140] L², L³, and L⁴ are each independently C₁-C₃₀ alkylene; C₂-C₃₀ alkenylene; or C₂-C₃₀ alkynylene;
  • [0141] each of B², B³, and B⁴ is independently an ionizable nitrogen-containing group;
  • [0142] R^1A is H or C₁-C₆ alkyl; and
  • [0143] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0144] In embodiments, R^1A is H.

[0145] In embodiments, R¹ is independently unsubstituted linear C₆-C₂₂ alkyl, unsubstituted linear C₆-C₂₂ alkenyl, unsubstituted linear C₆-C₂₂ alkynyl, unsubstituted branched C₆-C₂₂ alkyl, unsubstituted branched C₆-C₂₂ alkenyl, or unsubstituted branched C₆-C₂₂ alkynyl.

[0146] In embodiments, R¹ is independently unsubstituted C₆-C₂₂ alkyl.

[0147] In embodiments, R¹ is independently C₆-C₁₂ alkyl substituted by —O(CO)R⁵ or —C(O)OR⁵, wherein R⁵ is unsubstituted C₆-C₁₄ alkyl.

[0148] In embodiments, R¹ is independently unsubstituted C₆-C₂₂ alkenyl.

[0149] In embodiments, C₆-C₂₂ alkenyl is a monoalkenyl, a dienyl, or a trienyl.

[0150] In embodiments (e.g., of Formula (III) or (IV)), R¹ is independently

[0151]

[0152] In embodiments (e.g., of Formula (III) or (IV)), R¹ is independently

[0153]

[0154] In embodiments (e.g., of Formula (V) or (VI)), R¹ is independently

[0155]

[0156] In embodiments (e.g., of Formula (V) or (VI)), R¹ is independently

[0157]

[0158] In embodiments, each of L², L³, and L⁴ is unsubstituted C₁-C₁₀ alkylene.

[0159] In embodiments, each of L², L³, and L⁴ is (CH₂)₂, (CH₂)₃, (CH₂)₄, or (CH₂)₅.

[0160] In embodiments, each of B², B³, and B⁴ is independently NH₂, guanidine, amidine, a mono- or dialkylamine, 5- to 6-membered nitrogen-containing heterocycloalkyl, or 5- to 6-membered nitrogen-containing heteroaryl.

[0161] In embodiments, each of B², B³, and B⁴ is independently

[0162]

[0163] In embodiments, each of B², B³, and B⁴ is independently

[0164]

[0165] In embodiments, a cationic lipid is any of Compounds 1-264, Ia-Ih, IIb1-IIb4, IIc1-IIc4, IIIa-IIId, and Va-Vd, or a pharmaceutically acceptable salt thereof.

[0166] In embodiments, a cationic lipid is any of the compounds in any of Tables A-F, or a pharmaceutically acceptable salt thereof.

[0167] In another aspect, the invention features a composition comprising any liposome (e.g., a liposome encapsulating an mRNA encoding a protein) described herein.

[0168] In embodiments, an mRNA encodes for cystic fibrosis transmembrane conductance regulator (CFTR) protein.

[0169] In embodiments, an mRNA encodes for ornithine transcarbamylase (OTC) protein.

[0170] In another aspect, the invention features a composition comprising a nucleic acid encapsulated within a liposome as described herein.

[0171] In embodiments, a composition further comprises one more lipids selected from the group consisting of one or more cationic lipids, one or more non-cationic lipids, and one or more PEG-modified lipids.

[0172] In embodiments, a nucleic acid is an mRNA encoding a peptide or polypeptide.

[0173] In embodiments, a mRNA encodes a peptide or polypeptide for use in the delivery to or treatment of the lung of a subject or a lung cell.

[0174] In embodiments, a mRNA encodes a peptide or polypeptide for use in the delivery to or treatment of the lung of a subject or a lung cell.

[0175] In embodiments, an mRNA encodes for cystic fibrosis transmembrane conductance regulator (CFTR) protein.

[0176] In embodiments, a mRNA encodes a peptide or polypeptide for use in the delivery to or treatment of the liver of a subject or a liver cell.

[0177] In embodiments, a mRNA encodes for ornithine transcarbamylase (OTC) protein.

[0178] In embodiments, a mRNA encodes a peptide or polypeptide for use in vaccine.

[0179] In embodiments, a mRNA encodes an antigen.

[0180] In some aspects, the present invention provides methods of treating a disease in a subject comprising administering to the subject a composition as described herein.

[0182] In order for the present invention to be more readily understood, certain terms are first defined below. Additional definitions for the following terms and other terms are set forth throughout the specification. The publications and other reference materials referenced herein to describe the background of the invention and to provide additional detail regarding its practice are hereby incorporated by reference.

[0183] Amino acid: As used herein, the term “amino acid,” in its broadest sense, refers to any compound and/or substance that can be incorporated into a polypeptide chain. In some embodiments, an amino acid has the general structure H₂N—C(H)(R)—COOH. In some embodiments, an amino acid is a naturally occurring amino acid. In some embodiments, an amino acid is a synthetic amino acid; in some embodiments, an amino acid is a d-amino acid; in some embodiments, an amino acid is an I-amino acid. “Standard amino acid” refers to any of the twenty standard I-amino acids commonly found in naturally occurring peptides. “Nonstandard amino acid” refers to any amino acid, other than the standard amino acids, regardless of whether it is prepared synthetically or obtained from a natural source. As used herein, “synthetic amino acid” encompasses chemically modified amino acids, including but not limited to salts, amino acid derivatives (such as amides), and/or substitutions. Amino acids, including carboxy- and/or amino-terminal amino acids in peptides, can be modified by methylation, amidation, acetylation, protecting groups, and/or substitution with other chemical groups that can change the peptide's circulating half-life without adversely affecting their activity. Amino acids may participate in a disulfide bond. Amino acids may comprise one or posttranslational modifications, such as association with one or more chemical entities (e.g., methyl groups, acetate groups, acetyl groups, phosphate groups, formyl moieties, isoprenoid groups, sulfate groups, polyethylene glycol moieties, lipid moieties, carbohydrate moieties, biotin moieties, etc.). The term “amino acid” is used interchangeably with “amino acid residue,” and may refer to a free amino acid and/or to an amino acid residue of a peptide. It will be apparent from the context in which the term is used whether it refers to a free amino acid or a residue of a peptide.

[0184] Animal: As used herein, the term “animal” refers to any member of the animal kingdom. In some embodiments, “animal” refers to humans, at any stage of development. In some embodiments, “animal” refers to non-human animals, at any stage of development. In certain embodiments, the non-human animal is a mammal (e.g., a rodent, a mouse, a rat, a rabbit, a monkey, a dog, a cat, a sheep, cattle, a primate, and/or a pig). In some embodiments, animals include, but are not limited to, mammals, birds, reptiles, amphibians, fish, insects, and/or worms. In some embodiments, an animal may be a transgenic animal, genetically-engineered animal, and/or a clone.

[0185] Approximately or about: As used herein, the term “approximately” or “about,” as applied to one or more values of interest, refers to a value that is similar to a stated reference value. In certain embodiments, the term “approximately” or “about” refers to a range of values that fall within 25%, 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less in either direction (greater than or less than) of the stated reference value unless otherwise stated or otherwise evident from the context (except where such number would exceed 100% of a possible value).

[0186] Biologically active: As used herein, the term “biologically active” refers to a characteristic of any agent that has activity in a biological system, and particularly in an organism. For instance, an agent that, when administered to an organism, has a biological effect on that organism, is considered to be biologically active.

[0187] Delivery: As used herein, the term “delivery” encompasses both local and systemic delivery. For example, delivery of mRNA encompasses situations in which an mRNA is delivered to a target tissue and the encoded protein is expressed and retained within the target tissue (also referred to as “local distribution” or “local delivery”), and situations in which an mRNA is delivered to a target tissue and the encoded protein is expressed and secreted into patient's circulation system (e.g., serum) and systematically distributed and taken up by other tissues (also referred to as “systemic distribution” or “systemic delivery”).

[0188] Expression: As used herein, “expression” of a nucleic acid sequence refers to translation of an mRNA into a polypeptide, assemble multiple polypeptides into an intact protein (e.g., enzyme) and/or post-translational modification of a polypeptide or fully assembled protein (e.g., enzyme). In this application, the terms “expression” and “production,” and grammatical equivalent, are used inter-changeably.

[0189] Functional: As used herein, a “functional” biological molecule is a biological molecule in a form in which it exhibits a property and/or activity by which it is characterized.

[0190] Half-life: As used herein, the term “half-life” is the time required for a quantity such as nucleic acid or protein concentration or activity to fall to half of its value as measured at the beginning of a time period.

[0191] Improve, increase, or reduce: As used herein, the terms “improve,” “increase” or “reduce,” or grammatical equivalents, indicate values that are relative to a baseline measurement, such as a measurement in the same individual prior to initiation of the treatment described herein, or a measurement in a control subject (or multiple control subject) in the absence of the treatment described herein. A “control subject” is a subject afflicted with the same form of disease as the subject being treated, who is about the same age as the subject being treated.

[0192] In Vitro: As used herein, the term “in vitro” refers to events that occur in an artificial environment, e.g., in a test tube or reaction vessel, in cell culture, etc., rather than within a multi-cellular organism.

[0193] In Vivo: As used herein, the term “in vivo” refers to events that occur within a multi-cellular organism, such as a human and a non-human animal. In the context of cell-based systems, the term may be used to refer to events that occur within a living cell (as opposed to, for example, in vitro systems).

[0194] Isolated: As used herein, the term “isolated” refers to a substance and/or entity that has been (1) separated from at least some of the components with which it was associated when initially produced (whether in nature and/or in an experimental setting), and/or (2) produced, prepared, and/or manufactured by the hand of man. isolated substances and/or entities may be separated from about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or more than about 99% of the other components with which they were initially associated. In some embodiments, isolated agents are about 80%, about 85%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or more than about 99% pure. As used herein, a substance is “pure” if it is substantially free of other components. As used herein, calculation of percent purity of isolated substances and/or entities should not include excipients (e.g., buffer, solvent, water, etc.).

[0195] Liposome: As used herein, the term “liposome” refers to any lamellar, multilamellar, or solid nanoparticle vesicle. Typically, a liposome as used herein can be formed by mixing one or more lipids or by mixing one or more lipids and polymer(s). In some embodiments, a liposome suitable for the present invention contains a cationic lipids(s) and optionally non-cationic lipid(s), optionally cholesterol-based lipid(s), and/or optionally PEG-modified lipid(s).

[0196] messenger RNA (mRNA): As used herein, the term “messenger RNA (mRNA)” or “mRNA” refers to a polynucleotide that encodes at least one polypeptide. mRNA as used herein encompasses both modified and unmodified RNA. The term “modified mRNA” related to mRNA comprising at least one chemically modified nucleotide. mRNA may contain one or more coding and non-coding regions. mRNA can be purified from natural sources, produced using recombinant expression systems and optionally purified, chemically synthesized, etc. Where appropriate, e.g., in the case of chemically synthesized molecules, mRNA can comprise nucleoside analogs such as analogs having chemically modified bases or sugars, backbone modifications, etc. An mRNA sequence is presented in the 5′ to 3′ direction unless otherwise indicated. In some embodiments, an mRNA is or comprises natural nucleosides (e.g., adenosine, guanosine, cytidine, uridine); nucleoside analogs (e.g., 2-aminoadenosine, 2-thiothymidine, inosine, pyrrolo-pyrimidine, 3-methyl adenosine, 5-methylcytidine, C-5 propynyl-cytidine, C-5 propynyl-uridine, 2-aminoadenosine, C5-bromouridine, C5-fluorouridine, C5-iodouridine, C5-propynyl-uridine, C5-propynyl-cytidine, C5-methylcytidine, 2-aminoadenosine, 7-deazaadenosine, 7-deazaguanosine, 8-oxoadenosine, 8-oxoguanosine, O(6)-methylguanine, and 2-thiocytidine); chemically modified bases; biologically modified bases (e.g., methylated bases); intercalated bases; modified sugars (e.g., 2′-fluororibose, ribose, 2′-deoxyribose, arabinose, and hexose); and/or modified phosphate groups (e.g., phosphorothioates and 5′-N-phosphoramidite linkages).

[0197] Nucleic acid: As used herein, the term “nucleic acid,” in its broadest sense, refers to any compound and/or substance that is or can be incorporated into a polynucleotide chain. In some embodiments, a nucleic acid is a compound and/or substance that is or can be incorporated into a polynucleotide chain via a phosphodiester linkage. In some embodiments, “nucleic acid” refers to individual nucleic acid residues (e.g., nucleotides and/or nucleosides). In some embodiments, “nucleic acid” refers to a polynucleotide chain comprising individual nucleic acid residues. In some embodiments, “nucleic acid” encompasses RNA as well as single and/or double-stranded DNA and/or cDNA. In some embodiments, “nucleic acid” encompasses ribonucleic acids (RNA), including but not limited to any one or more of interference RNAs (RNAi), small interfering RNA (siRNA), short hairpin RNA (shRNA), antisense RNA (aRNA), messenger RNA (mRNA), modified messenger RNA (mmRNA), long non-coding RNA (lncRNA), micro-RNA (miRNA) multimeric coding nucleic acid (MCNA), polymeric coding nucleic acid (PCNA), guide RNA (gRNA) and CRISPR RNA (crRNA). In some embodiments, “nucleic acid” encompasses deoxyribonucleic acid (DNA), including but not limited to any one or more of single-stranded DNA (ssDNA), double-stranded DNA (dsDNA) and complementary DNA (cDNA). In some embodiments, “nucleic acid” encompasses both RNA and DNA. In embodiments, DNA may be in the form of antisense DNA, plasmid DNA, parts of a plasmid DNA, pre-condensed DNA, a product of a polymerase chain reaction (PCR), vectors (e.g., P1, PAC, BAC, YAC, artificial chromosomes), expression cassettes, chimeric sequences, chromosomal DNA, or derivatives of these groups. In embodiments, RNA may be in the form of messenger RNA (mRNA), ribosomal RNA (rRNA), signal recognition particle RNA (7 SL RNA or SRP RNA), transfer RNA (tRNA), transfer-messenger RNA (tmRNA), small nuclear RNA (snRNA), small nucleolar RNA (snoRNA), SmY RNA, small Cajal body-specific RNA (scaRNA), guide RNA (gRNA), ribonuclease P (RNase P), Y RNA, telomerase RNA component (TERC), spliced leader RNA (SL RNA), antisense RNA (aRNA or asRNA), cis-natural antisense transcript (cis-NAT), CRISPR RNA (crRNA), long noncoding RNA (lncRNA), micro-RNA (miRNA), piwi-interacting RNA (piRNA), small interfering RNA (siRNA), transacting siRNA (tasiRNA), repeat associated siRNA (rasiRNA), 73K RNA, retrotransposons, a viral genome, a viroid, satellite RNA, or derivatives of these groups. In some embodiments, a nucleic acid is a mRNA encoding a protein such as an enzyme.

[0198] Patient: As used herein, the term “patient” or “subject” refers to any organism to which a provided composition may be administered, e.g., for experimental, diagnostic, prophylactic, cosmetic, and/or therapeutic purposes. Typical patients include animals (e.g., mammals such as mice, rats, rabbits, non-human primates, and/or humans). In some embodiments, a patient is a human. A human includes pre- and post-natal forms.

[0199] Pharmaceutically acceptable: The term “pharmaceutically acceptable”, as used herein, refers to substances that, within the scope of sound medical judgment, are suitable for use in contact with the tissues of human beings and animals without excessive toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit/risk ratio.

[0200] Pharmaceutically acceptable salt: Pharmaceutically acceptable salts are well known in the art. For example, S. M. Berge et al., describes pharmaceutically acceptable salts in detail in J. Pharmaceutical Sciences (1977) 66:1-19. Pharmaceutically acceptable salts of the compounds of this invention include those derived from suitable inorganic and organic acids and bases. Examples of pharmaceutically acceptable, nontoxic acid addition salts are salts of an amino group formed with inorganic acids such as hydrochloric acid, hydrobromic acid, phosphoric acid, sulfuric acid and perchloric acid or with organic acids such as acetic acid, oxalic acid, maleic acid, tartaric acid, citric acid, succinic acid or rnalonic acid or by using other methods used in the art such as ion exchange. Other pharmaceutically acceptable salts include adipate, alginate, ascorbate, aspartate, benzenesulfonate, benzoate, bisulfate, borate, butyrate, camphorate, camphorsulfonate, citrate, cyclopentanepropionate, digluconate, dodecylsulfate, ethanesulfonate, formate, fumarate, glucoheptonate, glycerophosphate, gluconate, hemisulfate, heptanoate, hexanoate, hydroiodide, 2-hydroxy-ethanesulfonate, lactobionate, lactate, laurate, lauryl sulfate, malate, maleate, malonate, methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate, oleate, oxalate, palmitate, pamoate, pectinate, persulfate, 3-phenylpropionate, phosphate, picrate, pivalate, propionate, stearate, succinate, sulfate, tartrate, thiocyanate, p-toluenesulfonate, undecanoate, valerate salts, and the like. Salts derived from appropriate bases include alkali metal, alkaline earth metal, ammonium and N⁺(C_1-4 alkyl)₄ salts. Representative alkali or alkaline earth metal salts include sodium, lithium, potassium, calcium, magnesium, and the like. Further pharmaceutically acceptable salts include, when appropriate, nontoxic ammonium. quaternary ammonium, and amine cations formed using counterions such as halide, hydroxide, carboxylate, sulfate, phosphate, nitrate, sulfonate and aryl sulfonate. Further pharmaceutically acceptable salts include salts formed from the quaternization of an amine using an appropriate electrophile, e.g., an alkyl halide, to form a quarternized alkylated amino salt.

[0201] Systemic distribution or delivery: As used herein, the terms “systemic distribution,” “systemic delivery,” or grammatical equivalent, refer to a delivery or distribution mechanism or approach that affect the entire body or an entire organism. Typically, systemic distribution or delivery is accomplished via body's circulation system, e.g., blood stream. Compared to the definition of “local distribution or delivery.”

[0202] Subject: As used herein, the term “subject” refers to a human or any non-human animal (e.g., mouse, rat, rabbit, dog, cat, cattle, swine, sheep, horse or primate). A human includes pre- and post-natal forms. In many embodiments, a subject is a human being. A subject can be a patient, which refers to a human presenting to a medical provider for diagnosis or treatment of a disease. The term “subject” is used herein interchangeably with “individual” or “patient.” A subject can be afflicted with or is susceptible to a disease or disorder but may or may not display symptoms of the disease or disorder.

[0203] Substantially: As used herein, the term “substantially” refers to the qualitative condition of exhibiting total or near-total extent or degree of a characteristic or property of interest. One of ordinary skill in the biological arts will understand that biological and chemical phenomena rarely, if ever, go to completion and/or proceed to completeness or achieve or avoid an absolute result. The term “substantially” is therefore used herein to capture the potential lack of completeness inherent in many biological and chemical phenomena.

[0204] Target tissues: As used herein, the term “target tissues” refers to any tissue that is affected by a disease to be treated. In some embodiments, target tissues include those tissues that display disease-associated pathology, symptom, or feature.

[0205] Therapeutically effective amount: As used herein, the term “therapeutically effective amount” of a therapeutic agent means an amount that is sufficient, when administered to a subject suffering from or susceptible to a disease, disorder, and/or condition, to treat, diagnose, prevent, and/or delay the onset of the symptom(s) of the disease, disorder, and/or condition. It will be appreciated by those of ordinary skill in the art that a therapeutically effective amount is typically administered via a dosing regimen comprising at least one unit dose.

[0206] Treating: As used herein, the term “treat,” “treatment,” or “treating” refers to any method used to partially or completely alleviate, ameliorate, relieve, inhibit, prevent, delay onset of, reduce severity of and/or reduce incidence of one or more symptoms or features of a particular disease, disorder, and/or condition. Treatment may be administered to a subject who does not exhibit signs of a disease and/or exhibits only early signs of the disease for the purpose of decreasing the risk of developing pathology associated with the disease.

[0207] Aliphatic: As used herein, the term aliphatic refers to C₁-C₄₀ hydrocarbons and includes both saturated and unsaturated hydrocarbons. An aliphatic may be linear, branched, or cyclic. For example, C₁-C₂₀ aliphatics can include C₁-C₂₀ alkyls (e.g., linear or branched C₁-C₂₀ saturated alkyls), C₂-C₂₀ alkenyls (e.g., linear or branched C₄-C₂₀ dienyls, linear or branched C₆-C₂₀ trienyls, and the like), and C₂-C₂₀ alkynyls (e.g., linear or branched C₂-C₂₀ alkynyls). C₁-C₂₀ aliphatics can include C₃-C₂₀ cyclic aliphatics (e.g., C₃-C₂₀ cycloalkyls, C₄-C₂₀ cycloalkenyls, or C₈-C₂₀ cycloalkynyls). In certain embodiments, the aliphatic may comprise one or more cyclic aliphatic and/or one or more heteroatoms such as oxygen, nitrogen, or sulfur and may optionally be substituted with one or more substituents such as alkyl, halo, alkoxyl, hydroxy, amino, aryl, ether, ester or amide. An aliphatic group is unsubstituted or substituted with one or more substituent groups as described herein. For example, an aliphatic may be substituted with one or more (e.g., 1, 2, 3, 4, 5, or 6 independently selected substituents) of halogen, —COR′, —CO₂H, —CO₂R′, —CN, —OH, —OR′, —OCOR′, —OCO₂R′, —NH₂,

—NHR′, —N(R′)₂, —SR′ or —SO₂R′, wherein each instance of R′ independently is C₁-C₂₀ aliphatic (e.g., C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is an unsubstituted alkyl (e.g., unsubstituted C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is unsubstituted C₁-C₃ alkyl. In embodiments, the aliphatic is unsubstituted. In embodiments, the aliphatic does not include any heteroatoms.

[0208] Alkyl: As used herein, the term “alkyl” means acyclic linear and branched hydrocarbon groups, e.g. “C₁-C₂₀ alkyl” refers to alkyl groups having 1-20 carbons. An alkyl group may be linear or branched. Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl tert-pentylhexyl, Isohexyletc. Other alkyl groups will be readily apparent to those of skill in the art given the benefit of the present disclosure. An alkyl group may be unsubstituted or substituted with one or more substituent groups as described herein. For example, an alkyl group may be substituted with one or more (e.g., 1, 2, 3, 4, 5, or 6 independently selected substituents) of halogen, —COR′, —CO₂H, —CO₂R′, —CN, —OH, —OR′,

—OCOR′, —OCO₂R′, —NH₂, —NHR′, —N(R′)₂, —SR′ or —SO₂R′, wherein each instance of R′ independently is C₁-C₂₀ aliphatic (e.g., C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is an unsubstituted alkyl (e.g., unsubstituted C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is unsubstituted C₁-C₃ alkyl. In embodiments, the alkyl is substituted (e.g., with 1, 2, 3, 4, 5, or 6 substituent groups as described herein). In embodiments, an alkyl group is substituted with a —OH group and may also be referred to herein as a “hydroxyalkyl” group, where the prefix denotes the —OH group and “alkyl” is as described herein.

[0209] Alkylene: The term “alkylene,” as used herein, represents a saturated divalent straight or branched chain hydrocarbon group and is exemplified by methylene, ethylene, isopropylene and the like. Likewise, the term “alkenylene” as used herein represents an unsaturated divalent straight or branched chain hydrocarbon group having one or more unsaturated carbon-carbon double bonds that may occur in any stable point along the chain, and the term “alkynylene” herein represents an unsaturated divalent straight or branched chain hydrocarbon group having one or more unsaturated carbon-carbon triple bonds that may occur in any stable point along the chain. In certain embodiments, an alkylene, alkenylene, or alkynylene group may comprise one or more cyclic aliphatic and/or one or more heteroatoms such as oxygen, nitrogen, or sulfur and may optionally be substituted with one or more substituents such as alkyl, halo, alkoxyl, hydroxy, amino, aryl, ether, ester or amide. For example, an alkylene, alkenylene, or alkynylene may be substituted with one or more (e.g., 1, 2, 3, 4, 5, or 6 independently selected substituents) of halogen, —COR′, —CO₂H, —CO₂R′,

—CN, —OH, —OR′, —OCOR′, —OCO₂R′, —NH₂, —NHR′, —N(R′)₂, —SR′ or —SO₂R′, wherein each instance of R′ independently is C₁-C₂₀ aliphatic (e.g., C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is an unsubstituted alkyl (e.g., unsubstituted C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is unsubstituted C₁-C₃ alkyl. In certain embodiments, an alkylene, alkenylene, or alkynylene is unsubstituted. In certain embodiments, an alkylene, alkenylene, or alkynylene does not include any heteroatoms.

[0210] Alkenyl: As used herein, “alkenyl” means any linear or branched hydrocarbon chains having one or more unsaturated carbon-carbon double bonds that may occur in any stable point along the chain, e.g. “C₂-C₂₀ alkenyl” refers to an alkenyl group having 2-20 carbons. For example, an alkenyl group includes prop-2-enyl, but-2-enyl, but-3-enyl, 2-methylprop-2-enyl, hex-2-enyl, hex-5-enyl, 2,3-dimethylbut-2-enyl, and the like. In embodiments, the alkenyl comprises 1, 2, or 3 carbon-carbon double bond. In embodiments, the alkenyl comprises a single carbon-carbon double bond. In embodiments, multiple double bonds (e.g., 2 or 3) are conjugated. An alkenyl group may be unsubstituted or substituted with one or more substituent groups as described herein. For example, an alkenyl group may be substituted with one or more (e.g., 1, 2, 3, 4, 5, or 6 independently selected substituents) of halogen, —COR′, —CO₂H, —CO₂R′, —CN, —OH, —OR′, —OCOR′, —OCO₂R′, —NH₂, —NHR′, —N(R′)₂, —SR′ or —SO₂R′, wherein each instance of R′ independently is C₁-C₂₀ aliphatic (e.g., C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is an unsubstituted alkyl (e.g., unsubstituted C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is unsubstituted C₁-C₃ alkyl. In embodiments, the alkenyl is unsubstituted. In embodiments, the alkenyl is substituted (e.g., with 1, 2, 3, 4, 5, or 6 substituent groups as described herein). In embodiments, an alkenyl group is substituted with a-OH group and may also be referred to herein as a “hydroxyalkenyl” group, where the prefix denotes the —OH group and “alkenyl” is as described herein.

[0211] Alkynyl: As used herein, “alkynyl” means any hydrocarbon chain of either linear or branched configuration, having one or more carbon-carbon triple bonds occurring in any stable point along the chain, e.g. “C₂-C₂₀ alkynyl” refers to an alkynyl group having 2-20 carbons. Examples of an alkynyl group include prop-2-ynyl, but-2-ynyl, but-3-ynyl, pent-2-ynyl, 3-methylpent-4-ynyl, hex-2-ynyl, hex-5-ynyl, etc. In embodiments, an alkynyl comprises one carbon-carbon triple bond. An alkynyl group may be unsubstituted or substituted with one or more substituent groups as described herein. For example, an alkynyl group may be substituted with one or more (e.g., 1, 2, 3, 4, 5, or 6 independently selected substituents) of halogen, —COR′, —CO₂H, —CO₂R′, —CN, —OH, —OR′, —OCOR′,

—OCO₂R′, —NH₂, —NHR′, —N(R′)₂, —SR′ or —SO₂R′, wherein each instance of R′ independently is C₁-C₂₀ aliphatic (e.g., C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is an unsubstituted alkyl (e.g., unsubstituted C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is unsubstituted C₁-C₃ alkyl. In embodiments, the alkynyl is unsubstituted. In embodiments, the alkynyl is substituted (e.g., with 1, 2, 3, 4, 5, or 6 substituent groups as described herein).

[0212] Aryl: The terms “aryl” and “ar-”, used alone or as part of a larger moiety, e.g., “aralkyl”, “aralkoxy”, or “aryloxyalkyl”, refer to an optionally substituted C₆-14aromatic hydrocarbon moiety comprising one to three aromatic rings. For example, the aryl group is a C₆-10aryl group (i.e., phenyl and naphthyl). Aryl groups include, without limitation, optionally substituted phenyl, naphthyl, or anthracenyl. The terms “aryl” and “ar-”, as used herein, also include groups in which an aryl ring is fused to one or more cycloaliphatic rings to form an optionally substituted cyclic structure such as a tetrahydronaphthyl, indenyl, or indanyl ring. The term “aryl” may be used interchangeably with the terms “aryl group”, “aryl ring”, and “aromatic ring”.

[0213] Cycloalkyl: As used herein, the term “cycloalkyl” means a nonaromatic, saturated, cyclic group, e.g. “C₃-C₁₀ cycloalkyl.” In embodiments, a cycloalkyl is monocyclic. In embodiments, a cycloalkyl is polycyclic (e.g., bicyclic or tricyclic). In polycyclic cycloalkyl groups, individual rings can be fused, bridged, or spirocyclic. Examples of a cycloalkyl group include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, norbornanyl, bicyclo[3.2.1]octanyl, octahydro-pentalenyl, and spiro[4.5]decanyl, and the like. The term “cycloalkyl” may be used interchangeably with the term “carbocycle”. A cycloalkyl group may be unsubstituted or substituted with one or more substituent groups as described herein. For example, a cycloalkyl group may be substituted with one or more (e.g., 1, 2, 3, 4, 5, or 6 independently selected substituents) of halogen, —COR′, —CO₂H, —CO₂R′, —CN, —OH, —OR′, —OCOR′, —OCO₂R′, —NH₂, —NHR′, —N(R′)₂, —SR′ or —SO₂R′, wherein each instance of R′ independently is C₁-C₂₀ aliphatic (e.g., C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is an unsubstituted alkyl (e.g., unsubstituted C₁-C₂₀ alkyl, C₁-C₁₅ alkyl, C₁-C₁₀ alkyl, or C₁-C₃ alkyl). In embodiments, R′ independently is unsubstituted C₁-C₃ alkyl. In embodiments, the cycloalkyl is unsubstituted. In embodiments, the cycloalkyl is substituted (e.g., with 1, 2, 3, 4, 5, or 6 substituent groups as described herein).

[0214] Halogen: As used herein, the term “halogen” means fluorine, chlorine, bromine, or iodine.

[0215] Heteroalkenyl. The term “heteroalkenyl” is meant a branched or unbranched alkenyl group having from 2 to 14 carbon atoms in addition to 1, 2, 3 or 4 heteroatoms independently selected from the group consisting of N, O, S, and P. A heteroalkenyl may optionally include monocyclic, bicyclic, or tricyclic rings, in which each ring desirably has three to six members. The heteroalkenyl group may be substituted or unsubstituted.

[0216] Heteroalkynyl. The term “heteroalkynyl” is meant a branched or unbranched alkynyl group having from 2 to 14 carbon atoms in addition to 1, 2, 3 or 4 heteroatoms independently selected from the group consisting of N, O, S, and P. A heteroalkynyl may optionally include monocyclic, bicyclic, or tricyclic rings, in which each ring desirably has three to six members. The heteroalkynyl group may be substituted or unsubstituted.

[0217] Heteroalkyl. The term “heteroalkyl” is meant a branched or unbranched alkyl group having from 1 to 14 carbon atoms in addition to 1, 2, 3 or 4 heteroatoms independently selected from the group consisting of N, O, S, and P. Heteroalkyls include, without limitation, tertiary amines, secondary amines, ethers, thioethers, amides, thioamides, carbamates, thiocarbamates, hydrazones, imines, phosphodiesters, phosphoramidates, sulfonamides, and disulfides. A heteroalkyl may optionally include monocyclic, bicyclic, or tricyclic rings, in which each ring desirably has three to six members. The heteroalkyl group may be substituted or unsubstituted. Examples of heteroalkyls include, without limitation, polyethers, such as methoxymethyl and ethoxyethyl.

[0218] Heteroaryl: The terms “heteroaryl” and “heteroar-”, used alone or as part of a larger moiety, e.g., “heteroaralkyl”, or “heteroaralkoxy”, refer to groups having 5 to 14 ring atoms, preferably 5, 6, 9, or 10 ring atoms; having 6, 10, or 14 π electrons shared in a cyclic array; and having, in addition to carbon atoms, from one to five heteroatoms. A heteroaryl group may be mono-, bi-, tri-, or polycyclic, for example, mono-, bi-, or tricyclic (e.g., mono- or bicyclic). The term “heteroatom” refers to nitrogen, oxygen, or sulfur, and includes any oxidized form of nitrogen or sulfur, and any quaternized form of a basic nitrogen. For example, a nitrogen atom of a heteroaryl may be a basic nitrogen atom and may also be optionally oxidized to the corresponding N-oxide. When a heteroaryl is substituted by a hydroxy group, it also includes its corresponding tautomer. The terms “heteroaryl” and “heteroar-”, as used herein, also include groups in which a heteroaromatic ring is fused to one or more aryl, cycloaliphatic, or heterocycloaliphatic rings. Nonlimiting examples of heteroaryl groups include thienyl, furanyl, pyrrolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, oxazolyl, isoxazolyl, oxadiazolyl, thiazolyl, isothiazolyl, thiadiazolyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, indolizinyl, purinyl, naphthyridinyl, pteridinyl, indolyl, isoindolyl, benzothienyl, benzofuranyl, dibenzofuranyl, indazolyl, benzimidazolyl, benzthiazolyl, quinolyl, isoquinolyl, cinnolinyl, phthalazinyl, quinazolinyl, quinoxalinyl, 4H-quinolizinyl, carbazolyl, acridinyl, phenazinyl, phenothiazinyl, phenoxazinyl, tetrahydroquinolinyl, tetrahydroisoquinolinyl, and pyrido[2,3-b]-1,4-oxazin-3 (4H)-one. The term “heteroaryl” may be used interchangeably with the terms “heteroaryl ring”, “heteroaryl group”, or “heteroaromatic”, any of which terms include rings that are optionally substituted. The term “heteroaralkyl” refers to an alkyl group substituted by a heteroaryl, wherein the alkyl and heteroaryl portions independently are optionally substituted.

[0219] Heterocyclyl. As used herein, the terms “heterocycle”, “heterocyclyl”, “heterocyclic radical”, and “heterocyclic ring” are used interchangeably and refer to a stable 3- to 8-membered monocyclic or 7-10-membered bicyclic heterocyclic moiety that is either saturated or partially unsaturated, and having, in addition to carbon atoms, one or more, such as one to four, heteroatoms, as defined above. When used in reference to a ring atom of a heterocycle, the term “nitrogen” includes a substituted nitrogen. As an example, in a saturated or partially unsaturated ring having 0-3 heteroatoms selected from oxygen, sulfur or nitrogen, the nitrogen may be N (as in 3,4-dihydro-2H-pyrrolyl), NH (as in pyrrolidinyl), or NR⁺ (as in N-substituted pyrrolidinyl).

[0220] A heterocyclic ring can be attached to its pendant group at any heteroatom or carbon atom that results in a stable structure and any of the ring atoms can be optionally substituted. Examples of such saturated or partially unsaturated heterocyclic radicals include, without limitation, tetrahydrofuranyl, tetrahydrothienyl, piperidinyl, decahydroquinolinyl, oxazolidinyl, piperazinyl, dioxanyl, dioxolanyl, diazepinyl, oxazepinyl, thiazepinyl, morpholinyl, and thiamorpholinyl. A heterocyclyl group may be mono-, bi-, tri-, or polycyclic, preferably mono-, bi-, or tricyclic, more preferably mono- or bicyclic. The term “heterocyclylalkyl” refers to an alkyl group substituted by a heterocyclyl, wherein the alkyl and heterocyclyl portions independently are optionally substituted. Additionally, a heterocyclic ring also includes groups in which the heterocyclic ring is fused to one or more aryl rings.

Cationic Lipids

[0221] Liposomal-based vehicles are considered an attractive carrier for therapeutic agents and remain subject to continued development efforts. While liposomal-based vehicles that comprise a cationic lipid component have shown promising results with regards to encapsulation, stability and site localization, there remains a great need for improvement of liposomal-based delivery systems. For example, a significant drawback of liposomal delivery systems relates to the construction of liposomes that have sufficient cell culture or in vivo stability to reach desired target cells and/or intracellular compartments, and the ability of such liposomal delivery systems to efficiently release their encapsulated materials to such target cells.

[0222] In particular, there remains a need for improved cationic lipids that demonstrate improved pharmacokinetic properties and which are capable of delivering macromolecules, such as nucleic acids to a wide variety cell types and tissues with enhanced efficiency. Importantly, there also remains a particular need for novel cationic lipids that are characterized as having reduced toxicity and are capable of efficiently delivering encapsulated nucleic acids and polynucleotides to targeted cells, tissues and organs.

[0223] Described herein are novel cationic lipids, compositions comprising such lipids, and related methods of their use. In embodiments, the compounds described herein are useful as liposomal compositions or as components of liposomal compositions to facilitate the delivery to, and subsequent transfection of one or more target cells.

[0224] Cationic lipids disclosed herein comprise a basic, ionizable functional group (e.g., an amine or a nitrogen-containing heteroaryl as described herein), which is present in neutral or charged form.

[0225] For example, a basic, ionizable functional group can refer to a nitrogen functional group (e.g., NH₂, guanidine, amidine, a mono- or dialkylamine, 5- to 6-membered heterocycloalkyl, or 5- to 6-membered nitrogen-containing heteroaryl) that can be converted to a charged group by protonation with an acid or deprotonation with a base. Accordingly, in embodiments, X¹ is NH₂, guanidine, amidine, a mono- or dialkylamine, 5- to 6-membered heterocycloalkyl, or 5- to 6-membered nitrogen-containing heteroaryl. For example, in embodiments, an ionizable nitrogen-containing group is

[0226]

[0227] In embodiments, cationic lipids described herein can provide one or more desired characteristics or properties. That is, in certain embodiments, cationic lipids described herein can be characterized as having one or more properties that afford such compounds advantages relative to other similarly classified lipids. For example, cationic lipids disclosed herein can allow for the control and tailoring of the properties of liposomal compositions (e.g., lipid nanoparticles) of which they are a component. In particular, cationic lipids disclosed herein can be characterized by enhanced transfection efficiencies and their ability to provoke specific biological outcomes. Such outcomes can include, for example enhanced cellular uptake, endosomal/lysosomal disruption capabilities and/or promoting the release of encapsulated materials (e.g., polynucleotides) intracellularly.

[0228] In embodiments, a cationic lipid has a structure according to Formula (A):

[0229]
or a pharmaceutically acceptable salt thereof, wherein

• • [0230] each n is independently 0 or 1;
  • [0231] X^1A is independently O or NR^1A,
  • [0232] R^1A is H or C₁-C₆ alkyl;
  • [0233] X^1B is a covalent bond, C(O), CH₂CO₂, or CH₂C(O);
  • [0234] one of X^2A and X^2B is O and the other is a covalent bond;
  • [0235] one of X^3A and X^3B is O and the other is a covalent bond;
  • [0236] one of X^4A and X^4B is O and the other is a covalent bond;
  • [0237] R¹ is independently L¹-B¹, C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl;
  • [0238] R² is independently L²-B², C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl;
  • [0239] R³ is independently L³-B³, C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl;
  • [0240] R⁴ is independently L⁴-B⁴, C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl;
  • [0241] L¹, L², L³, and L⁴ are each independently C₁-C₃₀ alkylene; C₂-C₃₀ alkenylene; or C₂-C₃₀ alkynylene;
  • [0242] each of B¹, B², B³, and B⁴ is independently an ionizable nitrogen-containing group,
  • [0243] and
  • [0244] wherein the cationic lipid comprises at least one ionizable nitrogen-containing group.

[0245] In embodiments, each n is 1. In embodiments, two n are 2, and one n is 1.

[0246] In embodiments, X^1A is O. In embodiments, X^1A is NR^1A. In embodiments, X^1A is NH.

[0247] In embodiments, X^1B is a covalent bond. In embodiments, X^1B is C(O). In embodiments, X^1B is CH₂CO₂. In embodiments, X^1B is CH₂C(O).

[0248] In embodiments, X^2A is a covalent bond, and X^2B is O. In embodiments, X^3A is a covalent bond, and X^3B is O. In embodiments, X^4A is a covalent bond, and X^4B is O.

[0249] In embodiments, X^2A is O, and X^2B is a covalent bond. In embodiments, X^3A is O, and X^3B is a covalent bond. In embodiments, X^4A is O, and X^4B is a covalent bond.

[0250] In embodiments, each of X^2A, X^3A, and X^4A is a covalent bond, and each of X^2B, X^3B, and X^4B is O.

[0251] In embodiments, each of X^2A, X^3A, and X^4A is O, and each of X^2B, X^3B, and X^4B is a covalent bond.

[0252] In embodiments, the cationic lipid comprises one ionizable nitrogen-containing group.

[0253] In embodiments, the cationic lipid comprises two ionizable nitrogen-containing groups.

[0254] In embodiments, the cationic lipid comprises three ionizable nitrogen-containing groups. In embodiments, the cationic lipid comprises four ionizable nitrogen-containing groups.

[0255] In embodiments, a cationic lipid has a structure according to Formula (I),

[0256]

• • [0257] or a pharmaceutically acceptable salt thereof, wherein
  • [0258] each of R², R³, and R⁴ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl; and
  • [0259] L¹ is C₁-C₁₀ alkylene.

[0260] In embodiments, a cationic lipid has a structure according to Formula (I),

[0261]

• • [0262] or a pharmaceutically acceptable salt thereof, wherein
  • [0263] B¹ is an ionizable nitrogen-containing group;
  • [0264] each of R², R³, and R⁴ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl; and
  • [0265] L¹ is C₁-C₁₀ alkylene.

[0266] In embodiments, a cationic lipid has a structure according to Formula (AI),

[0267]

• • [0268] or a pharmaceutically acceptable salt thereof, wherein
  • [0269] L¹ is C₁-C₁₀ alkylene;
  • [0270] each R^6A is independently H or C₁-C₆ alkyl; and
  • [0271] each R^6B is independently H or C₁-C₆ alkyl.

[0272] In embodiments, a cationic lipid has a structure according to Formula (AII),

[0273]

• • [0274] or a pharmaceutically acceptable salt thereof.

[0275] In embodiments, a cationic lipid has a structure according to Formula (AIII),

[0276]

• • [0277] or a pharmaceutically acceptable salt thereof, wherein
  • [0278] R^1A is H.

[0279] In embodiments, a cationic lipid has a structure according to Formula (II),

[0280]

• • [0281] or a pharmaceutically acceptable salt thereof, wherein
  • [0282] each of R², R³, and R⁴ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl; and
  • [0283] L¹ is C₁-C₁₀ alkylene.

[0284] In embodiments, a cationic lipid has a structure according to Formula (II),

[0285]

• • [0286] or a pharmaceutically acceptable salt thereof, wherein
  • [0287] B¹ is an ionizable nitrogen-containing group;
  • [0288] R^1A is H or C₁-C₆ alkyl;
  • [0289] each of R², R³, and R⁴ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl; and
  • [0290] L¹ is C₁-C₁₀ alkylene.

[0291] In embodiments, R^1A is H.

[0292] In embodiments, L¹ is unsubstituted C₁-C₁₀ alkylene.

[0293] In embodiments, L¹ is (CH₂)₂, (CH₂)₃, (CH₂)₄, or (CH₂)₅.

[0294] In embodiments, L¹ is (CH₂), (CH₂)₆, (CH₂)₇, (CH₂)₈, (CH₂)₉, or (CH₂)₁₀.

[0295] In embodiments, B¹ is independently NH₂, guanidine, amidine, a mono- or dialkylamine, 5- to 6-membered nitrogen-containing heterocycloalkyl, or 5- to 6-membered nitrogen-containing heteroaryl.

[0296] In embodiments, B¹ is independently

[0297]

[0298] In embodiments, B¹ is independently

[0299]

[0300] In embodiments, B¹ is independently

[0301]

[0302] In embodiments, B¹ is independently

[0303]

[0304] In embodiments, B¹ is independently

[0305]

[0306] In embodiments, B¹ is independently

[0307]

[0308] In embodiments, each of R², R³, and R⁴ is independently C₈H₁₇, C₁₀H₂₁, C₁₂H₂₅, C₁₄H₂₉, C₁₆H₃₃, C₁₆H₃₁, C₁₆H₂₉ and C₁₆H₃₂.

[0309] In embodiments, each of R², R³, and R⁴ is independently C₆-C₂₂ alkyl, C₆-C₂₂ alkenyl, or C₆-C₂₂ alkynyl.

[0310] In embodiments, each of R², R³, and R⁴ is independently C₆-C₂₂ alkyl, or C₆-C₂₂ alkenyl.

[0311] In embodiments, each of R², R³, and R⁴ is independently unsubstituted linear C₆-C₂₂ alkyl, or unsubstituted linear C₆-C₂₂ alkenyl.

[0312] In embodiments, each of R², R³, and R⁴ is independently unsubstituted linear C₆-C₂₂ alkyl, unsubstituted linear C₆-C₂₂ alkenyl, unsubstituted linear C₆-C₂₂ alkynyl, unsubstituted branched C₆-C₂₂ alkyl, unsubstituted branched C₆-C₂₂ alkenyl, or unsubstituted branched C₆-C₂₂ alkynyl.

[0313] In embodiments, each of R², R³, and R⁴ is unsubstituted C₆-C₂₂ alkyl.

[0314] In embodiments, each of R², R³, and R⁴ is —C₆H₁₃, —C₇H₁₅, —C₈H₁₇, —C₉H₁₉, —C₁₀H₂₁, —C₁₁H₂₃,

• • [0315] —C₁₂H₂₅,
  • [0316] —C₁₃H₂₇, —C₁₄H₂₉, —C₁₅H₃₁, —C₁₆H₃₃, —C₁₇H₃₅, —C₁₈H₃₇, —C₁₉H₃₉, —C₂₀H₄₁, —C₂₁H₄₃, —C₂₂H₄₅, —C₂₃H₄₇, —C₂₄H₄₉,
  • [0317] or
  • [0318] —C₂₅H₅₁.

[0319] In embodiments, each of R², R³, and R⁴ is independently C₆-C₁₂ alkyl substituted by —O(CO)R⁵ or —C(O)OR⁵, wherein R⁵ is unsubstituted C₆-C₁₄ alkyl.

[0320] In embodiments, each of R², R³, and R⁴ is unsubstituted C₆-C₂₂ alkenyl. In embodiments, said C₆-C₂₂ alkenyl is a monoalkenyl, a dienyl, or a trienyl.

[0321] In embodiments, each of R², R³, and R⁴ is —(CH₂)₄CH═CH₂, —(CH₂)₅CH═CH₂, —(CH₂)₆CH═CH₂, —(CH₂)₇CH═CH₂, —(CH₂): CH═CH₂, —(CH₂)₉CH═CH₂, —(CH₂)₁₀CH═CH₂, —(CH₂)₁₁CH═CH₂, —(CH₂)₁₂CH═CH₂, —(CH₂)₁₃CH═CH₂, —(CH₂)₁₄CH═CH₂, —(CH₂)₁₅CH═CH₂, —(CH₂)₁₆CH═CH₂, —(CH₂)₁₇CH═CH₂, —(CH₂)₁₈CH═CH₂, —(CH₂)₇CH═CH(CH₂)₃CH₃, —(CH₂)₇CH═CH(CH₂)₅CH₃, —(CH₂)₄CH═CH(CH₂)₈CH₃, —(CH₂)₇CH═CH(CH₂)₇CH₃, —(CH₂)₆CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₁₁CH═CH(CH₂)₇CH₃, or —(CH₂)₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃.

[0322] In embodiments, each of R², R³, and R⁴ is

[0323]

[0324] In embodiments, each of R², R³, and R⁴ is

[0325]

[0326] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0327]

[0328] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0329]

[0330] In embodiments, each of R², R³, and R⁴ is

[0331]

[0332] In embodiments, each of R², R³, and R⁴ is

[0333]

[0334] In embodiments, each of R², R³, and R⁴ is

[0335]

[0336] In embodiments, each of R², R³, and R⁴ is

[0337]

[0338] In embodiments, each of R², R³, and R⁴ is

[0339]

[0340] In embodiments, each of R², R³, and R⁴ is

[0341]

[0342] In embodiments, each of R², R³, and R⁴ is

[0343]

[0344] In embodiments, each of R², R³, and R⁴ is

[0345]

[0346] In embodiments, each of R², R³, and R⁴ is

[0347]

[0348] In embodiments, each of R², R³, and R⁴ is

[0349]

[0350] In embodiments, each of R², R³, and R⁴ is

[0351]

[0352] In embodiments, each of R², R³, and R⁴ is

[0353]

[0354] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0355]

[0356] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0357]

[0358] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0359]

[0360] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0361]

[0362] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0363]

[0364] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0365]

[0366] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0367]

[0368] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0369]

[0370] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0371]

[0372] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0373]

[0374] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0375]

[0376] In embodiments, (e.g., of Formula (AI), (AII), (AIII), or (II)) each of R², R³, and R⁴ is

[0377]

[0378] In embodiments, a cationic lipid has a structure according to Formula (IIa),

[0379]

• • [0380] or a pharmaceutically acceptable salt thereof, wherein
  • [0381] B¹ is an ionizable nitrogen-containing group;
  • [0382] R^1A is H or C(O)—R⁷;
  • [0383] each of R², R³, R⁴, and R⁷ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl; and
  • [0384] L¹ is C₁-C₁₀ alkylene.

[0385] In embodiments of Formula (IIa), R^1A is H.

[0386] In embodiments of Formula (IIa), R^1A is C(O)—R⁷. In embodiments of Formula (IIa), L¹ is unsubstituted C₁-C₁₀ alkylene.

[0387] In embodiments of Formula (IIa), L¹ is (CH₂)₂, (CH₂)₃, (CH₂)₄, or (CH₂)₅.

[0388] In embodiments of Formula (IIa), L¹ is (CH₂), (CH₂)₆, (CH₂)₇, (CH₂)₈, (CH₂)₉, or (CH₂)₁₀.

[0389] In embodiments of Formula (IIa), L¹ is (CH₂)₂.

[0390] In embodiments of Formula (IIa), B¹ is independently NH₂, guanidine, amidine, a mono- or dialkylamine, 5- to 6-membered nitrogen-containing heterocycloalkyl, or 5- to 6-membered nitrogen-containing heteroaryl.

[0391] In embodiments of Formula (IIa), B¹ is independently

[0392]

[0393] In embodiments of Formula (IIa), B¹ is independently

[0394]

[0395] In embodiments of Formula (IIa), B¹ is independently

[0396]

[0397] In embodiments of Formula (IIa), B¹ is independently

[0398]

[0399] In embodiments of Formula (IIa), B¹ is independently

[0400]

[0401] In embodiments of Formula (IIa), B¹ is independently

[0402]

[0403] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₈H₁₇, C₁₀H₂₁, C₁₂H₂₅, C₁₄H₂₉, C₁₆H₃₃, C₁₆H₃₁, C₁₆H₂₉ and C₁₆H₃₂.

[0404] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₆-C₂₂ alkyl, C₆-C₂₂ alkenyl, or C₆-C₂₂ alkynyl.

[0405] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₆-C₂₂ alkyl, or C₆-C₂₂ alkenyl.

[0406] In embodiments, each of R², R³, R⁴, and R⁷ is independently unsubstituted linear C₆-C₂₂ alkyl, or unsubstituted linear C₆-C₂₂ alkenyl.

[0407] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is independently unsubstituted linear C₆-C₂₂ alkyl, unsubstituted linear C₆-C₂₂ alkenyl, unsubstituted linear C₆-C₂₂ alkynyl, unsubstituted branched C₆-C₂₂ alkyl, unsubstituted branched C₆-C₂₂ alkenyl, or unsubstituted branched C₆-C₂₂ alkynyl.

[0408] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is unsubstituted C₆-C₂₂ alkyl.

[0409] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is —C₆H₁₃, —C₇H₁₅, —C₈H₁₇, —C₉H₁₉, —C₁₀H₂₁, —C₁₁H₂₃, —C₁₂H₂₅, —C₁₃H₂₇, —C₁₄H₂₉, —C₁₅H₃₁, —C₁₆H₃₃, —C₁₇H₃₅, —C₁₈H₃₇, —C₁₉H₃₉, —C₂₀H₄₁, —C₂₁H₄₃, —C₂₂H₄₅, —C₂₃H₄₇, —C₂₄H₄₉, or

• • [0410] —C₂₅H₅₁.

[0411] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is independently C₆-C₁₂ alkyl substituted by —O(CO)R⁵ or —C(O)OR⁵, wherein R⁵ is unsubstituted C₆-C₁₄ alkyl.

[0412] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is unsubstituted C₆-C₂₂ alkenyl. In embodiments, said C₆-C₂₂ alkenyl is a monoalkenyl, a dienyl, or a trienyl.

[0413] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is —(CH₂)₄CH═CH₂, —(CH₂)₅CH═CH₂, —(CH₂)₆CH═CH₂, —(CH₂)₇CH═CH₂, —(CH₂) &CH═CH₂, —(CH₂)₉CH═CH₂, —(CH₂)₁₀CH═CH₂, —(CH₂)₁₁CH═CH₂, —(CH₂)₁₂CH═CH₂, —(CH₂)₁₃CH═CH₂, —(CH₂)₁₄CH═CH₂, —(CH₂)₁₅CH═CH₂, —(CH₂)₁₆CH═CH₂, —(CH₂)₁₇CH═CH₂, —(CH₂)₁₈CH═CH₂, —(CH₂)₇CH═CH(CH₂)₃CH₃, —(CH₂)₇CH═CH(CH₂)₅CH₃, —(CH₂)₄CH═CH(CH₂)₈CH₃, —(CH₂)₇CH═CH(CH₂)₇CH₃, —(CH₂)₆CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₁₁CH═CH(CH₂)₇CH₃, or —(CH₂)₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃.

[0414] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0415]

[0416] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0417]

[0418] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0419]

[0420] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0421]

[0422] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0423]

[0424] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0425]

[0426] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0427]

[0428] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0429]

[0430] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0431]

[0432] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0433]

[0434] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0435]

[0436] In embodiments of Formula (IIa), each of R², R³, R⁴, and R⁷ is

[0437]

[0438] In embodiments of Formula (IIa), each of R², R³, R⁴ and R⁷ is

[0439]

[0440] In embodiments, the cationic lipid has a structure according to Formula (IIb),

[0441]

• • [0442] or a pharmaceutically acceptable salt thereof, wherein
  • [0443] B¹ is an ionizable nitrogen-containing group;
  • [0444] R^1A is H or C(O)—R⁷; and
  • [0445] each of R², R³, R⁴, and R⁷ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0446] In embodiments of Formula (IIb), R^1A is H.

[0447] In embodiments of Formula (IIb), R^1A is C(O)—R⁷.

[0448] In embodiments of Formula (IIb), B¹ is independently NH₂, guanidine, amidine, a mono- or

[0449] dialkylamine, 5- to 6-membered nitrogen-containing heterocycloalkyl, or 5- to 6-membered nitrogen-containing heteroaryl.

[0450] In embodiments of Formula (IIb), B¹ is independently

[0451]

[0452] In embodiments of Formula (IIb), B¹ is independently

[0453]

[0454] In embodiments of Formula (IIb), B¹ is independently

[0455]

[0456] In embodiments of Formula (IIb), B¹ is independently

[0457]

[0458] In embodiments of Formula (IIb), B¹ is independently

[0459]

[0460] In embodiments of Formula (IIb), B¹ is independently

[0461]

[0462] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₈H₁₇, C₁₀H₂₁, C₁₂H₂₅, C₁₄H₂₉, C₁₆H₃₃, C₁₆H₃₁, C₁₆H₂₉ and C₁₆H₃₂.

[0463] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₆-C₂₂ alkyl, C₆-C₂₂ alkenyl, or C₆-C₂₂ alkynyl.

[0464] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₆-C₂₂ alkyl, or C₆-C₂₂ alkenyl.

[0465] In embodiments, each of R², R³, R⁴, and R⁷ is independently unsubstituted linear C₆-C₂₂ alkyl, or unsubstituted linear C₆-C₂₂ alkenyl.

[0466] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is independently unsubstituted linear C₆-C₂₂ alkyl, unsubstituted linear C₆-C₂₂ alkenyl, unsubstituted linear C₆-C₂₂ alkynyl, unsubstituted branched C₆-C₂₂ alkyl, unsubstituted branched C₆-C₂₂ alkenyl, or unsubstituted branched C₆-C₂₂ alkynyl.

[0467] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is unsubstituted C₆-C₂₂ alkyl.

[0468] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is —C₆H₁₃, —C₇H₁₅, —C₈H₁₇, —C₉H₁₉, —C₁₀H₂₁, —C₁₁H₂₃, —C₁₂H₂₅, —C₁₃H₂₇, —C₁₄H₂₉, —C₁₅H₃₁, —C₁₆H₃₃, —C₁₇H₃₅, —C₁₈H₃₇, —C₁₉H₃₉, —C₂₀H₄₁, —C₂₁H₄₃, —C₂₂H₄₅, —C₂₃H₄₇, —C₂₄H₄₉, or

• • [0469] —C₂₅H₅₁.

[0470] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is independently C₆-C₁₂ alkyl substituted by —O(CO)R⁵ or —C(O)OR⁵, wherein R⁵ is unsubstituted C₆-C₁₄ alkyl.

[0471] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is unsubstituted C₆-C₂₂ alkenyl. In embodiments, said C₆-C₂₂ alkenyl is a monoalkenyl, a dienyl, or a trienyl.

[0472] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is —(CH₂)₄CH═CH₂, —(CH₂)₅CH═CH₂, —(CH₂)₆CH═CH₂,

• • [0473] —(CH₂)₇CH═CH₂, —(CH₂): CH═CH₂, —(CH₂)₉CH═CH₂, —(CH₂)₁₀CH═CH₂, —(CH₂)₁₁CH═CH₂, —(CH₂)₁₂CH═CH₂, —(CH₂)₁₃CH═CH₂, —(CH₂)₁₄CH═CH₂, —(CH₂)₁₅CH═CH₂, —(CH₂)₁₆CH═CH₂, —(CH₂)₁₇CH═CH₂, —(CH₂)₁₈CH═CH₂, —(CH₂)₇CH═CH(CH₂)₃CH₃, —(CH₂)₇CH═CH(CH₂)₅CH₃, —(CH₂)₄CH═CH(CH₂)₈CH₃, —(CH₂)₇CH═CH(CH₂)₇CH₃, —(CH₂)₆CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₁₁CH═CH(CH₂)₇CH₃, or
  • [0474] —(CH₂)₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃.

[0475] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0476]

[0477] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0478]

[0479] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0480]

[0481] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0482]

[0483] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0484]

[0485] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0486]

[0487] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0488]

[0489] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0490]

[0491] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0492]

[0493] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0494]

[0495] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0496]

[0497] In embodiments of Formula (IIb), each of R², R³, R⁴, and R⁷ is

[0498]

[0499] In embodiments of Formula (IIb), each of R², R³, R⁴ and R⁷ is

[0500]

[0501] In embodiments, the cationic lipid has a structure according to Formula (IIc),

[0502]

• • [0503] or a pharmaceutically acceptable salt thereof, wherein
  • [0504] B¹ is an ionizable nitrogen-containing group; and
  • [0505] each of R², R³, R⁴, and R⁷ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0506] In embodiments of Formula (IIc), B¹ is independently NH₂, guanidine, amidine, a mono- or dialkylamine, 5- to 6-membered nitrogen-containing heterocycloalkyl, or 5- to 6-membered nitrogen-containing heteroaryl.

[0507] In embodiments of Formula (IIc), B¹ is independently

[0508]

[0509] In embodiments of Formula (IIc), B¹ is independently

[0510]

[0511] In embodiments of Formula (IIc), B¹ is independently

[0512]

[0513] In embodiments of Formula (IIc), B¹ is independently

[0514]

[0515] In embodiments of Formula (IIc), B¹ is independently

[0516]

[0517] In embodiments of Formula (IIc), B¹ is independently

[0518]

[0519] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₈H₁₇, C₁₀H₂₁, C₁₂H₂₅, C₁₄H₂₉, C₁₆H₃₃, C₁₆H₃₁, C₁₆H₂₉ and C₁₆H₃₂.

[0520] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₆-C₂₂ alkyl, C₆-C₂₂ alkenyl, or C₆-C₂₂ alkynyl.

[0521] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₆-C₂₂ alkyl, or C₆-C₂₂ alkenyl.

[0522] In embodiments, each of R², R³, R⁴, and R⁷ is independently unsubstituted linear C₆-C₂₂ alkyl, or unsubstituted linear C₆-C₂₂ alkenyl.

[0523] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is independently unsubstituted linear C₆-C₂₂ alkyl, unsubstituted linear C₆-C₂₂ alkenyl, unsubstituted linear C₆-C₂₂ alkynyl, unsubstituted branched C₆-C₂₂ alkyl, unsubstituted branched C₆-C₂₂ alkenyl, or unsubstituted branched C₆-C₂₂ alkynyl.

[0524] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is unsubstituted C₆-C₂₂ alkyl.

[0525] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is —C₆H₁₃, —C₇H₁₅, —C₈H₁₇, —C₉H₁₉, —C₁₀H₂₁, —C₁₁H₂₃, —C₁₂H₂₅, —C₁₃H₂₇, —C₁₄H₂₉, —C₁₅H₃₁, —C₁₆H₃₃, —C₁₇H₃₅, —C₁₈H₃₇, —C₁₉H₃₉, —C₂₀H₄₁, —C₂₁H₄₃, —C₂₂H₄₅, —C₂₃H₄₇, —C₂₄H₄₉, or

• • [0526] —C₂₅H₅₁.

[0527] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is independently C₆-C₁₂ alkyl substituted by —O(CO)R⁵ or —C(O)OR⁵, wherein R⁵ is unsubstituted C₆-C₁₄ alkyl.

[0528] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is unsubstituted C₆-C₂₂ alkenyl. In embodiments, said C₆-C₂₂ alkenyl is a monoalkenyl, a dienyl, or a trienyl.

[0529] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is —(CH₂)₄CH═CH₂, —(CH₂)₅CH═CH₂, —(CH₂)₆CH═CH₂,

• • [0530] —(CH₂)₇CH═CH₂, —(CH₂): CH═CH₂, —(CH₂)₉CH═CH₂, —(CH₂)₁₀CH═CH₂, —(CH₂)₁₁CH═CH₂, —(CH₂)₁₂CH═CH₂, —(CH₂)₁₃CH═CH₂, —(CH₂)₁₄CH═CH₂, —(CH₂)₁₅CH═CH₂, —(CH₂)₁₆CH═CH₂, —(CH₂)₁₇CH═CH₂, —(CH₂)₁₈CH═CH₂, —(CH₂)—CH═CH(CH₂)₃CH₃, —(CH₂)₇CH═CH(CH₂)₅CH₃, —(CH₂)₄CH═CH(CH₂)₈CH₃, —(CH₂)₇CH═CH(CH₂)₇CH₃, —(CH₂)₆CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₁₁CH═CH(CH₂)₇CH₃, or
  • [0531] —(CH₂)₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃.

[0532] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0533]

[0534] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0535]

[0536] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0537]

[0538] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0539]

[0540] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0541]

[0542] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0543]

[0544] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0545]

[0546] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0547]

[0548] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0549]

[0550] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0551]

[0552] In embodiments of Formula (IIc), each of R², R³, R⁴, and R⁷ is

[0553]

[0554] In embodiments of Formula (IIc), each of R², R³, R⁴ and R⁷ is

[0555]

[0556] In embodiments of Formula (IIc), each of R², R³, R⁴ and R⁷ is

[0557]

[0558] In embodiments, a cationic lipid has a structure according to Formula (IId),

[0559]

• • [0560] or a pharmaceutically acceptable salt thereof, wherein
  • [0561] B¹ is an ionizable nitrogen-containing group; and
  • [0562] each of R², R³, R⁴, and R⁷ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0563] In embodiments of Formula (IId), B¹ is independently NH₂, guanidine, amidine, a mono- or dialkylamine, 5- to 6-membered nitrogen-containing heterocycloalkyl, or 5- to 6-membered nitrogen-containing heteroaryl.

[0564] In embodiments of Formula (IId), B¹ is independently

[0565]

[0566] In embodiments of Formula (IId), B¹ is independently

[0567]

[0568] In embodiments of Formula (IId), B¹ is independently

[0569]

[0570] In embodiments of Formula (IId), B¹ is independently

[0571]

[0572] In embodiments of Formula (IId), B¹ is independently

[0573]

[0574] In embodiments of Formula (IId), B¹ is independently

[0575]

[0576] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is independently unsubstituted linear C₆-C₂₂ alkyl, unsubstituted linear C₆-C₂₂ alkenyl, unsubstituted linear C₆-C₂₂ alkynyl, unsubstituted branched C₆-C₂₂ alkyl, unsubstituted branched C₆-C₂₂ alkenyl, or unsubstituted branched C₆-C₂₂ alkynyl.

[0577] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is unsubstituted C₆-C₂₂ alkyl.

[0578] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₈H₁₇, C₁₀H₂₁, C₁₂H₂₅, C₁₄H₂₉, C₁₆H₃₃, C₁₆H₃₁, C₁₆H₂₉ and C₁₆H₃₂.

[0579] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₆-C₂₂ alkyl, C₆-C₂₂ alkenyl, or C₆-C₂₂ alkynyl.

[0580] In embodiments, each of R², R³, R⁴, and R⁷ is independently C₆-C₂₂ alkyl, or C₆-C₂₂ alkenyl.

[0581] In embodiments, each of R², R³, R⁴, and R⁷ is independently unsubstituted linear C₆-C₂₂ alkyl, or unsubstituted linear C₆-C₂₂ alkenyl.

[0582] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is —C₆H₁₃, —C₇H₁₅, —C₈H₁₇, —C₉H₁₉, —C₁₀H₂₁, —C₁₁H₂₃, —C₁₂H₂₅, —C₁₃H₂₇, —C₁₄H₂₉, —C₁₅H₃₁, —C₁₆H₃₃, —C₁₇H₃₅, —C₁₈H₃₇, —C₁₉H₃₉, —C₂₀H₄₁, —C₂₁H₄₃, —C₂₂H₄₅, —C₂₃H₄₇, —C₂₄H₄₉, or

• • [0583] —C₂₅H₅₁.

[0584] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is independently C₆-C₁₂ alkyl substituted by —O(CO)R⁵ or —C(O)OR⁵, wherein R⁵ is unsubstituted C₆-C₁₄ alkyl.

[0585] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is unsubstituted C₆-C₂₂ alkenyl. In embodiments, said C₆-C₂₂ alkenyl is a monoalkenyl, a dienyl, or a trienyl.

[0586] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is —(CH₂)₄CH═CH₂, —(CH₂)₅CH═CH₂, —(CH₂)₆CH═CH₂,

• • [0587] —(CH₂)₇CH═CH₂, —(CH₂): CH═CH₂, —(CH₂)₉CH═CH₂, —(CH₂)₁₀CH═CH₂, —(CH₂)₁₁CH═CH₂, —(CH₂)₁₂CH═CH₂, —(CH₂)₁₃CH═CH₂, —(CH₂)₁₄CH═CH₂, —(CH₂)₁₅CH═CH₂, —(CH₂)₁₆CH═CH₂, —(CH₂)₁₇CH═CH₂, —(CH₂)₁₈CH═CH₂, —(CH₂)₇CH═CH(CH₂)₃CH₃, —(CH₂)₇CH═CH(CH₂)₅CH₃, —(CH₂)₄CH═CH(CH₂)₈CH₃, —(CH₂)₇CH═CH(CH₂)₇CH₃, —(CH₂)₆CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₁₁CH═CH(CH₂)₇CH₃, or
  • [0588] —(CH₂)₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃.

[0589] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0590]

[0591] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0592]

[0593] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0594]

[0595] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0596]

[0597] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0598]

[0599] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0600]

[0601] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0602]

[0603] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0604]

[0605] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0606]

[0607] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0608]

[0609] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0610]

[0611] In embodiments of Formula (IId), each of R², R³, R⁴, and R⁷ is

[0612]

[0613] In embodiments of Formula (IId), each of R², R³, R⁴ and R⁷ is

[0614]

[0615] In embodiments, a cationic lipid has a structure according to Formula (III),

[0616]
or a pharmaceutically acceptable salt thereof, wherein

• • [0617] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0618] In embodiments, a cationic lipid has a structure according to Formula (III),

[0619]
or a pharmaceutically acceptable salt thereof, wherein

• • [0620] L², L³, and L⁴ are each independently C₁-C₃₀ alkylene; C₂-C₃₀ alkenylene; or C₂-C₃₀ alkynylene;
  • [0621] each of B², B³, and B⁴ is independently an ionizable nitrogen-containing group; and
  • [0622] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0623] In embodiments, a cationic lipid has a structure according to Formula (IV),

[0624]
or a pharmaceutically acceptable salt thereof, wherein

• • [0625] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0626] In embodiments, a cationic lipid has a structure according to Formula (IV),

[0627]
or a pharmaceutically acceptable salt thereof, wherein

• • [0628] L², L³, and L⁴ are each independently C₁-C₃₀ alkylene; C₂-C₃₀ alkenylene; or C₂-C₃₀ alkynylene;
  • [0629] each of B², B³, and B⁴ is independently an ionizable nitrogen-containing group;
  • [0630] R^1A is H or C₁-C₆ alkyl; and
  • [0631] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0632] In embodiments, R^1A is H.

[0633] In embodiments, a cationic lipid has a structure according to Formula (V),

[0634]
or a pharmaceutically acceptable salt thereof, wherein

• • [0635] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0636] In embodiments, a cationic lipid has a structure according to Formula (V),

[0637]
or a pharmaceutically acceptable salt thereof, wherein

• • [0638] L², L³, and L⁴ are each independently C₁-C₃₀ alkylene; C₂-C₃₀ alkenylene; or C₂-C₃₀ alkynylene;
  • [0639] each of B², B³, and B⁴ is independently an ionizable nitrogen-containing group; and
  • [0640] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0641] In embodiments, a cationic lipid has a structure according to Formula (VI),

[0642]
or a pharmaceutically acceptable salt thereof, wherein

• • [0643] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0644] In embodiments, a cationic lipid has a structure according to Formula (VI),

[0645]
or a pharmaceutically acceptable salt thereof, wherein

• • [0646] L², L³, and L⁴ are each independently C₁-C₃₀ alkylene; C₂-C₃₀ alkenylene; or C₂-C₃₀ alkynylene;
  • [0647] each of B², B³, and B⁴ is independently an ionizable nitrogen-containing group,
  • [0648] R^1A is H or C₁-C₆ alkyl; and
  • [0649] R¹ is independently C₆-C₃₀ alkyl, C₆-C₃₀ alkenyl, or C₆-C₃₀ alkynyl.

[0650] In embodiments, R^1A is H.

[0651] In embodiments, R¹ is independently C₈H₁₇, C₁₀H₂₁, C₁₂H₂₅, C₁₄H₂₉, C₁₆H₃₃, C₁₆H₃₁, C₁₆H₂₉ and C₁₆H₃₂.

[0652] In embodiments, R¹ is independently unsubstituted linear C₆-C₂₂ alkyl, unsubstituted linear C₆-C₂₂ alkenyl, or unsubstituted linear C₆-C₂₂ alkynyl.

[0653] In embodiments, R¹ is independently unsubstituted linear C₆-C₂₂ alkyl, unsubstituted linear C₆-C₂₂ alkenyl, unsubstituted linear C₆-C₂₂ alkynyl, unsubstituted branched C₆-C₂₂ alkyl, unsubstituted branched C₆-C₂₂ alkenyl, or unsubstituted branched C₆-C₂₂ alkynyl.

[0654] In embodiments, R¹ is independently unsubstituted C₆-C₂₂ alkyl.

[0655] In embodiments, R¹ is independently —C₆H₁₃, —C₇H₁₅, —C₈H₁₇, —C₉H₁₉, —C₁₀H₂₁, —C₁₁H₂₃, —C₁₂H₂₅, —C₁₃H₂₇, —C₁₄H₂₉, —C₁₅H₃₁, —C₁₆H₃₃, —C₁₇H₃₅, —C₁₈H₃₇, —C₁₉H₃₉, —C₂₀H₄₁, —C₂₁H₄₃, —C₂₂H₄₅, —C₂₃H₄₇, —C₂₄H₄₉, or

• • [0656] —C₂₅H₅₁.

[0657] In embodiments, R¹ is independently C₆-C₁₂ alkyl substituted by —O(CO)R⁵ or —C(O)OR⁵, wherein R⁵ is unsubstituted C₆-C₁₄ alkyl.

[0658] In embodiments, R¹ is independently unsubstituted C₆-C₂₂ alkenyl.

[0659] In embodiments, R¹ is independently-(CH₂)₄CH═CH₂, —(CH₂)₅CH═CH₂, —(CH₂)₆CH═CH₂, —(CH₂)₇CH═CH₂, —(CH₂): CH═CH₂, —(CH₂)₉CH═CH₂, —(CH₂)₁₀CH═CH₂, —(CH₂)₁₁CH═CH₂, —(CH₂)₁₂CH═CH₂, —(CH₂)₁₃CH═CH₂, —(CH₂)₁₄CH═CH₂, —(CH₂)₁₅CH═CH₂, —(CH₂)₁₆CH═CH₂, —(CH₂)₁₇CH═CH₂, —(CH₂)₁₈CH═CH₂, —(CH₂)₇CH═CH(CH₂)₃CH₃, —(CH₂)₇CH═CH(CH₂)₅CH₃, —(CH₂)₄CH═CH(CH₂)₈CH₃, —(CH₂)₇CH═CH(CH₂) CH₃, —(CH₂)₆CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₇CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₄CH₃, —(CH₂)₃CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃, —(CH₂)₁₁CH═CH(CH₂)₇CH₃, or

• • [0660] —(CH₂)₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH₃.

[0661] In embodiments, C₆-C₂₂ alkenyl is a monoalkenyl, a dienyl, or a trienyl.

[0662] In embodiments (e.g., of Formula (III) or (IV)), R¹ is independently

[0663]

[0664] In embodiments (e.g., of Formula (III) or (IV)), R¹ is independently

[0665]

[0666] In embodiments, R¹ is independently

[0667]

[0668] In embodiments, R¹ is independently

[0669]

[0670] In embodiments, R¹ is independently

[0671]

[0672] In embodiments, R¹ is independently

[0673]

[0674] In embodiments, R¹ is independently

[0675]

[0676] In embodiments, R¹ is independently

[0677]

[0678] In embodiments, R¹ is independently

[0679]

[0680] In embodiments, R¹ is independently

[0681]

[0682] In embodiments, R¹ is independently

[0683]

[0684] In embodiments, R¹ is independently

[0685]

[0686] In embodiments, R¹ is independently

[0687]

[0688] In embodiments, R¹ is independently

[0689]

[0690] In embodiments (e.g., of Formula (V) or (VI)), R¹ is independently

[0691]

[0692] In embodiments (e.g., of Formula (V) or (VI)), R¹ is independently

[0693]

[0694] In embodiments, R¹ is independently

[0695]

[0696] In embodiments, R¹ is independently

[0697]

[0698] In embodiments, R¹ is independently

[0699]

[0700] In embodiments, R¹ is independently

[0701]

[0702] In embodiments, R¹ is independently

[0703]

[0704] In embodiments, R¹ is independently

[0705]

[0706] In embodiments, R¹ is independently

[0707]

[0708] In embodiments, R¹ is independently

[0709]

[0710] In embodiments, R¹ is independently

[0711]

[0712] In embodiments, R¹ is independently

[0713]

[0714] In embodiments, R¹ is independently

[0715]

[0716] In embodiments, R¹ is independently

[0717]

[0718] In embodiments, each of L², L³, and L⁴ is unsubstituted C₁-C₁₀ alkylene.

[0719] In embodiments, each of L², L³, and L⁴ is (CH₂)₂, (CH₂)₃, (CH₂)₄, or (CH₂)₅.

[0720] In embodiments, each of L², L³, and L⁴ is (CH₂), (CH₂)₆, (CH₂)₇, (CH₂)₈, (CH₂)₉, or (CH₂)₁₀.

[0721] In embodiments, each of B², B³, and B⁴ is independently NH₂, guanidine, amidine, a mono- or dialkylamine, 5- to 6-membered nitrogen-containing heterocycloalkyl, or 5- to 6-membered nitrogen-containing heteroaryl.

[0722] In embodiments, each of B², B³, and B⁴ is independently

[0723]

[0724] In embodiments, each of B², B³, and B⁴ is independently

[0725]

[0726] In embodiments, each of B², B³, and B⁴ is independently

[0727]

[0728] In embodiments, each of B², B³, and B⁴ is independently

[0729]

[0730] In embodiments, each of B², B³, and B⁴ is independently

[0731]

[0732] In embodiments, each of B², B³, and B⁴ is independently

[0733]
Exemplary Cationic Lipids

[0734] In embodiments, a cationic lipid is any compound described in Table A.

[0735]

TABLE A
Exemplary Compounds of Formula (I)
Compound	R2 = R3 = R4 =	B1 =
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
Ia
Ib
Ic
Id

[0736] In embodiments, a cationic lipid is Compound 1. In embodiments, a cationic lipid is Compound 2. In embodiments, a cationic lipid is Compound 3. In embodiments, a cationic lipid is Compound 4.

[0737] In embodiments, a cationic lipid is Compound 5. In embodiments, a cationic lipid is Compound 6. In embodiments, a cationic lipid is Compound 7. In embodiments, a cationic lipid is Compound 8.

[0738] In embodiments, a cationic lipid is Compound 9. In embodiments, a cationic lipid is Compound 10. In embodiments, a cationic lipid is Compound 11. In embodiments, a cationic lipid is Compound 12.

[0739] In embodiments, a cationic lipid is Compound 13. In embodiments, a cationic lipid is Compound 14. In embodiments, a cationic lipid is Compound 15. In embodiments, a cationic lipid is Compound 16.

[0740] In embodiments, a cationic lipid is Compound 17. In embodiments, a cationic lipid is Compound 18. In embodiments, a cationic lipid is Compound 19. In embodiments, a cationic lipid is Compound 20.

[0741] In embodiments, a cationic lipid is Compound 21. In embodiments, a cationic lipid is Compound 22. In embodiments, a cationic lipid is Compound 23. In embodiments, a cationic lipid is Compound 24.

[0742] In embodiments, a cationic lipid is Compound 25. In embodiments, a cationic lipid is Compound 26. In embodiments, a cationic lipid is Compound 27. In embodiments, a cationic lipid is Compound 28.

[0743] In embodiments, a cationic lipid is Compound 29. In embodiments, a cationic lipid is Compound 30. In embodiments, a cationic lipid is Compound 31. In embodiments, a cationic lipid is Compound 32.

[0744] In embodiments, a cationic lipid is Compound 33. In embodiments, a cationic lipid is Compound 34. In embodiments, a cationic lipid is Compound 35. In embodiments, a cationic lipid is Compound 36.

[0745] In embodiments, a cationic lipid is Compound 37. In embodiments, a cationic lipid is Compound 38. In embodiments, a cationic lipid is Compound 39. In embodiments, a cationic lipid is Compound 40.

[0746] In embodiments, a cationic lipid is Compound 41. In embodiments, a cationic lipid is Compound 42. In embodiments, a cationic lipid is Compound 43. In embodiments, a cationic lipid is Compound 44.

[0747] In embodiments, a cationic lipid is Compound Ia. In embodiments, a cationic lipid is Compound Ib. In embodiments, a cationic lipid is Compound Ic. In embodiments, a cationic lipid is Compound Id.

[0748] In embodiments, a cationic lipid is any compound described in Table B.

[0749]

TABLE B
Exemplary Compounds of Formula (III)
Compound	R1 =	B2 = B3 = B4 =
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
IIIa
IIIb
IIIc
IIId

[0750] In embodiments, a cationic lipid is Compound 45. In embodiments, a cationic lipid is Compound 46. In embodiments, a cationic lipid is Compound 47. In embodiments, a cationic lipid is Compound 48.

[0751] In embodiments, a cationic lipid is Compound 49. In embodiments, a cationic lipid is Compound 50. In embodiments, a cationic lipid is Compound 51. In embodiments, a cationic lipid is Compound 52.

[0752] In embodiments, a cationic lipid is Compound 53. In embodiments, a cationic lipid is Compound 54. In embodiments, a cationic lipid is Compound 55. In embodiments, a cationic lipid is Compound 56.

[0753] In embodiments, a cationic lipid is Compound 57. In embodiments, a cationic lipid is Compound 58. In embodiments, a cationic lipid is Compound 59. In embodiments, a cationic lipid is Compound 60.

[0754] In embodiments, a cationic lipid is Compound 61. In embodiments, a cationic lipid is Compound 62. In embodiments, a cationic lipid is Compound 63. In embodiments, a cationic lipid is Compound 64.

[0755] In embodiments, a cationic lipid is Compound 65. In embodiments, a cationic lipid is Compound 66. In embodiments, a cationic lipid is Compound 67. In embodiments, a cationic lipid is Compound 68.

[0756] In embodiments, a cationic lipid is Compound 69. In embodiments, a cationic lipid is Compound 70. In embodiments, a cationic lipid is Compound 71. In embodiments, a cationic lipid is Compound 72.

[0757] In embodiments, a cationic lipid is Compound 73. In embodiments, a cationic lipid is Compound 74. In embodiments, a cationic lipid is Compound 75. In embodiments, a cationic lipid is Compound 76.

[0758] In embodiments, a cationic lipid is Compound 77. In embodiments, a cationic lipid is Compound 78. In embodiments, a cationic lipid is Compound 79. In embodiments, a cationic lipid is Compound 80.

[0759] In embodiments, a cationic lipid is Compound 81. In embodiments, a cationic lipid is Compound 82. In embodiments, a cationic lipid is Compound 83. In embodiments, a cationic lipid is Compound 84.

[0760] In embodiments, a cationic lipid is Compound 85. In embodiments, a cationic lipid is Compound 86. In embodiments, a cationic lipid is Compound 87. In embodiments, a cationic lipid is Compound 88.

[0761] In embodiments, a cationic lipid is Compound IIIa. In embodiments, a cationic lipid is Compound IIIb. In embodiments, a cationic lipid is Compound IIIc. In embodiments, a cationic lipid is Compound IIId.

[0762] In embodiments, a cationic lipid is any compound described in Table C.

[0763]

TABLE C
Exemplary Compounds of Formula (V)
Compound	R1 =	B2 = B3 = B4 =
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
Va
Vb
Vc
Vd

[0764] In embodiments, a cationic lipid is Compound 89. In embodiments, a cationic lipid is Compound 90. In embodiments, a cationic lipid is Compound 91. In embodiments, a cationic lipid is Compound 92.

[0765] In embodiments, a cationic lipid is Compound 93. In embodiments, a cationic lipid is Compound 94. In embodiments, a cationic lipid is Compound 95. In embodiments, a cationic lipid is Compound 96.

[0766] In embodiments, a cationic lipid is Compound 97. In embodiments, a cationic lipid is Compound 98. In embodiments, a cationic lipid is Compound 99. In embodiments, a cationic lipid is Compound 100.

[0767] In embodiments, a cationic lipid is Compound 101. In embodiments, a cationic lipid is Compound 102. In embodiments, a cationic lipid is Compound 103. In embodiments, a cationic lipid is Compound 104.

[0768] In embodiments, a cationic lipid is Compound 105. In embodiments, a cationic lipid is Compound 106. In embodiments, a cationic lipid is Compound 107. In embodiments, a cationic lipid is Compound 108.

[0769] In embodiments, a cationic lipid is Compound 109. In embodiments, a cationic lipid is Compound 110. In embodiments, a cationic lipid is Compound 111. In embodiments, a cationic lipid is Compound 112.

[0770] In embodiments, a cationic lipid is Compound 113. In embodiments, a cationic lipid is Compound 114. In embodiments, a cationic lipid is Compound 115. In embodiments, a cationic lipid is Compound 116.

[0771] In embodiments, a cationic lipid is Compound 117. In embodiments, a cationic lipid is Compound 118. In embodiments, a cationic lipid is Compound 119. In embodiments, a cationic lipid is Compound 120.

[0772] In embodiments, a cationic lipid is Compound 121. In embodiments, a cationic lipid is Compound 122. In embodiments, a cationic lipid is Compound 123. In embodiments, a cationic lipid is Compound 124.

[0773] In embodiments, a cationic lipid is Compound 125. In embodiments, a cationic lipid is Compound 126. In embodiments, a cationic lipid is Compound 127. In embodiments, a cationic lipid is Compound 128.

[0774] In embodiments, a cationic lipid is Compound 129. In embodiments, a cationic lipid is Compound 130. In embodiments, a cationic lipid is Compound 131. In embodiments, a cationic lipid is Compound 132.

[0775] In embodiments, a cationic lipid is Compound Va. In embodiments, a cationic lipid is Compound Vb. In embodiments, a cationic lipid is Compound Vc. In embodiments, a cationic lipid is Compound Vd.

[0776] In embodiments, a cationic lipid is any compound described in Table D.

[0777]

TABLE D
Exemplary Compounds of Formula (IIb)
Compound	R2 = R3 = R4 =	B1 =
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
IIb1
IIb2
IIb3
IIb4

[0778] In embodiments, a cationic lipid is Compound 133. In embodiments, a cationic lipid is Compound 134. In embodiments, a cationic lipid is Compound 135. In embodiments, a cationic lipid is Compound 136.

[0779] In embodiments, a cationic lipid is Compound 137. In embodiments, a cationic lipid is Compound 133. In embodiments, a cationic lipid is Compound 139. In embodiments, a cationic lipid is Compound 140.

[0780] In embodiments, a cationic lipid is Compound 134. In embodiments, a cationic lipid is Compound 135. In embodiments, a cationic lipid is Compound 143. In embodiments, a cationic lipid is Compound 136.

[0781] In embodiments, a cationic lipid is Compound 137. In embodiments, a cationic lipid is Compound 138. In embodiments, a cationic lipid is Compound 139. In embodiments, a cationic lipid is Compound 140.

[0782] In embodiments, a cationic lipid is Compound 141. In embodiments, a cationic lipid is Compound 142. In embodiments, a cationic lipid is Compound 143. In embodiments, a cationic lipid is Compound 144.

[0783] In embodiments, a cationic lipid is Compound 145. In embodiments, a cationic lipid is Compound 154. In embodiments, a cationic lipid is Compound 155. In embodiments, a cationic lipid is Compound 156.

[0784] In embodiments, a cationic lipid is Compound 157. In embodiments, a cationic lipid is Compound 158. In embodiments, a cationic lipid is Compound 159. In embodiments, a cationic lipid is Compound 160.

[0785] In embodiments, a cationic lipid is Compound 161. In embodiments, a cationic lipid is Compound 162. In embodiments, a cationic lipid is Compound 163. In embodiments, a cationic lipid is Compound 164.

[0786] In embodiments, a cationic lipid is Compound 165. In embodiments, a cationic lipid is Compound 166. In embodiments, a cationic lipid is Compound 167. In embodiments, a cationic lipid is Compound 168.

[0787] In embodiments, a cationic lipid is Compound 169. In embodiments, a cationic lipid is Compound 170. In embodiments, a cationic lipid is Compound 171. In embodiments, a cationic lipid is Compound 172.

[0788] In embodiments, a cationic lipid is Compound 173. In embodiments, a cationic lipid is Compound 174. In embodiments, a cationic lipid is Compound 175. In embodiments, a cationic lipid is Compound 176.

[0789] In embodiments, a cationic lipid is Compound IIb1. In embodiments, a cationic lipid is Compound IIb2. In embodiments, a cationic lipid is Compound IIb3. In embodiments, a cationic lipid is Compound IIb4.

[0790] In embodiments, a cationic lipid is any compound described in Table E.

[0791]

TABLE E
Exemplary Compounds of Formula (IIc)
Compound	R2 = R3 = R4 = R7 =	B1 =
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
IIc1
IIc2
IIc3
IIc4

[0792] In embodiments, a cationic lipid is Compound 177. In embodiments, a cationic lipid is Compound 178. In embodiments, a cationic lipid is Compound 179. In embodiments, a cationic lipid is Compound 180.

[0793] In embodiments, a cationic lipid is Compound 181. In embodiments, a cationic lipid is Compound 146. In embodiments, a cationic lipid is Compound 183. In embodiments, a cationic lipid is Compound 184.

[0794] In embodiments, a cationic lipid is Compound 185. In embodiments, a cationic lipid is Compound 186. In embodiments, a cationic lipid is Compound 187. In embodiments, a cationic lipid is Compound 188.

[0795] In embodiments, a cationic lipid is Compound 189. In embodiments, a cationic lipid is Compound 190. In embodiments, a cationic lipid is Compound 191. In embodiments, a cationic lipid is Compound 192.

[0796] In embodiments, a cationic lipid is Compound 193. In embodiments, a cationic lipid is Compound 194. In embodiments, a cationic lipid is Compound 195. In embodiments, a cationic lipid is Compound 196.

[0797] In embodiments, a cationic lipid is Compound 197. In embodiments, a cationic lipid is Compound 198. In embodiments, a cationic lipid is Compound 199. In embodiments, a cationic lipid is Compound 200.

[0798] In embodiments, a cationic lipid is Compound 201. In embodiments, a cationic lipid is Compound 202. In embodiments, a cationic lipid is Compound 203. In embodiments, a cationic lipid is Compound 204.

[0799] In embodiments, a cationic lipid is Compound 205. In embodiments, a cationic lipid is Compound 206. In embodiments, a cationic lipid is Compound 207. In embodiments, a cationic lipid is Compound 208.

[0800] In embodiments, a cationic lipid is Compound 209. In embodiments, a cationic lipid is Compound 210. In embodiments, a cationic lipid is Compound 211. In embodiments, a cationic lipid is Compound 212.

[0801] In embodiments, a cationic lipid is Compound 213. In embodiments, a cationic lipid is Compound 214. In embodiments, a cationic lipid is Compound 215. In embodiments, a cationic lipid is Compound 216.

[0802] In embodiments, a cationic lipid is Compound 217. In embodiments, a cationic lipid is Compound 218. In embodiments, a cationic lipid is Compound 219. In embodiments, a cationic lipid is Compound 220.

[0803] In embodiments, a cationic lipid is Compound IIc1. In embodiments, a cationic lipid is Compound IIc2. In embodiments, a cationic lipid is Compound IIc3. In embodiments, a cationic lipid is Compound IIc4.

[0804]

TABLE F
Exemplary Compounds of Formula (I)
Compound	R2 = R3 = R4 =	B1 =
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
Ie
If
Ig
Ih