CKK-E12 is a ionizable lipid in combination with other lipids make up the lipid nanoparticles which are used to deliver RNA-based therapeutics. cKK-E12 was highly selective toward liver parenchymal cell in vivo.Multitail lipids usually have three or more tails and tend to form more cone-shaped structures due to the increase of tail crosssection, which enhances the endosome escape and mRNA delivery efficiency.CKK-E12 is an ionizable lipid with four lipid tails and diketopiperazine core-based head. It has shown excellent efficiency in delivering CRISPR-Cas9 mRNA and sgRNA.cKK-E12 iLNPs encapsulated mRNA was used to investigate the effect of Toll-like receptor 4 (TLR4) on iLNPsmediated mRNA delivery, and it has been demonstrated that the targeting, safety and efficacy of iLNPs are closely related to disease state. In other words, even though iLNP delivers therapeutic mRNA to a given cell type in one disease state, it is not guaranteed to deliver mRNA to the same cell type in another disease. As same as MC3 and C12-200, CKK-E12 is also used to be a positive control ionizable lipid when exploiting new ionizable lipids.

ALC 0307 is an ionizable amino lipid developed by Acuitas Therapeutics, serving as the critical functional component in lipid nanoparticles (LNPs) for targeted therapeutic delivery. As the core cationic lipid in specific LNP formulations (e.g., k-abe for CPS1-Q335X correction), its key feature is pH-dependent chargeability: it remains neutral at physiological pH but becomes positively charged in acidic environments like endosomes. This property enables efficient encapsulation of nucleic acid payloads (>97% efficiency, e.g., base editor mRNA/gRNA complexes) and facilitates endosomal escape via membrane disruption post-cellular uptake.​​ Its optimized structure promotes selective hepatocyte targeting by binding endogenous apolipoprotein E (ApoE), which subsequently interacts with LDL receptors on liver cells. Preclinical studies show rapid clearance (>99.5% plasma reduction in 14 days) and manageable transient toxicity (mild, reversible cytoplasmic vacuolation in hepatocytes, short-term ALT/AST elevation). LNPs containing ALC0307, alongside helper lipids (cholesterol, DSPC, and PEG-lipid ALC-0159), form stable ~73 nm particles with low polydispersity. This combination enables repeatable, liver-directed delivery of gene editing therapeutics with minimized off-target effects, underpinning its use in individualized in vivo gene correction therapies.

XH-04 (Lipid#4)​​ is an ionizable lipid engineered for advanced mRNA delivery developed by ​​JiaChen West Lake Biotech. Its core structure features a central benzene ring with asymmetric hydrophobic tails (C9-C10 chains) and pH-responsive tertiary amines that enable efficient mRNA encapsulation and endosomal escape. As detailed in CN113993839A, XH04 outperforms industry benchmarks (e.g., MC3 lipid), boosting protein expression by ​​>10-fold​​ in BHK cells. In PCT/CN2024/121624, JiaChen further demonstrated its utility in lung-targeted LNPs (tLNP/tLCNP). When combined with cationic lipids (e.g., DOTMA at 2:1 molar ratio), XH 04 redirects >80% of mRNA delivery to murine lungs—overcoming liver tropism—while maintaining low toxicity. The lipid’s benzenic core and optimized alkyl chain geometry (patent claims 1-9) are credited for enhanced endosomal disruption and mRNA release kinetics. JiaChen’s innovations position XH-04 as a cornerstone for next-generation mRNA therapeutics.

LIPID168(pKa ~6.5) ​​ is an optimized ionizable lipid engineered for in vivo mRNA delivery to hematopoietic stem cells (HSCs) in bone marrow. Developed by ​​Yoltech Therapeutics​​ through high-throughput screening of lipid libraries, it features a ​​diethylamino head group​​ and a tailored hydrophobic tail structure that enables antibody-free targeting. When Lipid 168 was formulated into lipid nanoparticles (LNPs), it achieved ​​48.5% base editing efficiency​​ in bone marrow cells —surpassing benchmarks like LIPID-028 (19.7%)—and reduced off-target liver editing from 71% to 19% by incorporating ​​miR-122 target sequences​​. In humanized β-thalassemia models, LNP 168 delivered ABE8e mRNA/sgRNA to patient-derived HSCs, yielding ​​42.6% editing at the HBG promoter​​, reactivating fetal hemoglobin (γ-globin) and rescuing erythroid defects . Its bone marrow specificity is driven by a unique ​​protein corona​​ enriched in albumin, fibronectin, and fibrinogen . Safety studies confirmed transient immune responses and no cumulative toxicity . LIPID-168 represents a promising non-viral platform for curative gene therapies in blood disorders.

​​DM3-BTA-14​​ is a cationic lipid compound engineered for high-efficiency mRNA delivery developed by Hefei AlphaNA Biotechnology. Its structure features a rigid benzene-1,3,5-tricarboxamide core linked to a protonatable dimethylamino headgroup (-N(CH₃)₂) via a propylene spacer (-CH₂CH₂CH₂-) and two saturated C14 alkyl chains. This design enables ≈90% endosomal escape efficiency , superior lymph node targeting for vaccines , and effective tumor-specific mRNA delivery . It outperforms benchmark lipids while maintaining low cytotoxicity, forming stable nanoparticles with cholesterol/DSPC/DSPE-PEG (50:39:10:1 ratio) for therapeutic applications.

A1-EP10-O18A​​ is an ​​asymmetric ionizable lipid​​ developed by Starna Therapeutics for mRNA vaccine delivery. Synthesized via Michael addition between amine alcohols and acrylates, its optimized structure—combining a hydrophilic C10 chain and hydrophobic unsaturated C18 tail—enables pH-dependent ionization. As the core component of the ​​STAR0225 lipid nanoparticle (LNP)​​ platform, it efficiently encapsulates mRNA and facilitates endosomal escape. Preclinical studies demonstrate superior in vivo mRNA delivery (vs. commercial SM102 LNPs), with enhanced local biodistribution and minimal off-target accumulation. This lipid underpins ​​STR-V003​​, an RSV prefusion F mRNA vaccine showing robust immunogenicity and protection in animal models, supporting its clinical transition (NCT06344975).

DMA4-H228 is a novel, biodegradable lipidoid specifically engineered for spleen-targeted mRNA delivery.​​ Its structure combines a dimethylamino (DMA4) headgroup with a unique hyperbranched lipid tail (H228) synthesized via Michael addition, incorporating ester bonds for enhanced biodegradability. This design enables the formation of stable lipid nanoparticles (LNPs) (~170 nm) with high mRNA encapsulation efficiency (>96%). Critically, DMA4-H228 exhibits exceptional intrinsic tropism for the spleen (>98% targeting efficiency after IV administration), requiring no external targeting ligands. It selectively delivers mRNA to splenic antigen-presenting cells (APCs), including dendritic cells, macrophages, and B cells. This triggers potent immune activation: rapid IFNα secretion, upregulation of APC maturation markers (CD86/CD40), and robust antigen-specific immune responses. Demonstrating significant therapeutic potential, DMA4-H228-based mRNA vaccines effectively inhibit tumor growth in melanoma models (e.g., B16F10-OVA). This correlates with increased tumor-infiltrating CD8⁺ T cells, a shift towards pro-inflammatory M1 macrophages, elevated antigen-specific antibodies (IgG), and strong T cell responses (evidenced by IFNγ⁺ spots). Its ability to bypass liver tropism and directly activate splenic APCs makes DMA4-H228 a powerful platform for next-generation mRNA vaccines and cancer immunotherapy.

E10i-494 is a branched ionizable lipid designed to enhance the delivery of mRNA and CRISPR-Cas9 ribonucleoprotein (RNP) complexes. It belongs to the Branched Endosomal Disruptor (BEND) lipid family, which features terminal branching to improve endosomal escape and cellular uptake.E10i-494 demonstrated exceptional performance in T cell engineering, achieving >80% transfection efficiency in primary human T cells. This is significantly higher than the ~70% efficiency achieved by the linear lipid C14-494.The isopropyl branch enhances the lipid's ability to penetrate and disrupt endosomal membranes, leading to improved release of mRNA and RNPs into the cytoplasm.Despite its high efficiency, E10i-494 exhibits low cytotoxicity, making it suitable for therapeutic applications.E10i-494 is particularly effective for delivering mRNA to T cells, making it a promising tool for CAR-T cell therapy and other immunotherapies.Its ability to deliver CRISPR-Cas9 RNPs efficiently also makes it suitable for in vivo gene editing applications.

CICL 207 is structurally optimized based on Lipid CICL-1. CICL207​​ is a constrained ionizable cationic lipid designed for lipid nanoparticle (LNP) delivery systems developed by Capstan. Its structure features a ​​rigid cyclic backbone​​ (e.g., pyrrolidine-derived core) paired with a ​​tertiary amine group​​ that ionizes at acidic pH (pKa ~6.5–7.0), enhancing endosomal escape. The lipid includes ​​asymmetric hydrophobic tails​​ (likely C14–C18 alkyl/ester chains) to stabilize LNP membranes and improve nucleic acid encapsulation. Integrated into LNPs (e.g., 58% CICL-207, 10% DSPC, 30.5% cholesterol, PEG-lipids), it enables targeted delivery to T cells (anti-CD5/CD8 tLNPs) with ​​high transfection efficiency​​ (spleen T cells >70% mCherry+), ​​reduced liver uptake​​, and ​​low toxicity​​ (no significant ALT/AST elevation in rats). Its constrained design balances stability, tissue specificity, and biocompatibility for gene therapy applications.CICL 207 (F50) significantly outperforms CICL-1 by delivering dramatically enhanced target cell transfection with reduced off-target effects. It achieves >50% transfection efficiency in splenic T-cells—nearly double that of CICL-1—while slashing off-target expression in liver cells to <5% (versus >15% for CICL-1. This precision translates to superior therapeutic outcomes: CICL-207 enables ~95% B-cell depletion in CAR-T applications, far exceeding CICL-1 ’s ~60% efficacy. Critically, it maintains an exceptional safety profile, showing no significant liver toxicity or inflammatory cytokine elevation even at high doses. Furthermore, CICL-207 demonstrates 2-fold higher transfection efficiency in hematopoietic stem cells, enabling robust gene editing. Its optimized pKa (~6.5) and constrained amine structure enhance endosomal escape while minimizing Kupffer cell uptake, making it ideal for targeted therapeutics requiring both potency and safety.​

Lipid S4 is an advanced ionizable lipid engineered for systemic mRNA delivery to the brain, leveraging SR-57227—a high-affinity 5-HT3 receptor ligand—as its core head group to enable targeted blood-brain barrier (BBB) penetration via receptor-mediated transcytosis, while incorporating amino linkers for pH-responsive ionization and biodegradable branched ester tails to facilitate efficient endosomal escape and intracellular mRNA release; optimized through orthogonal screening into OS4 LNP (formulated at S4/DOPE/Chol/DMG-PEG2k = 40:40:60:0.75 molar ratio), it demonstrated a 13.3-fold increase in brain mRNA expression compared to FDA-approved MC3 LNPs, and further conjugation with the Tat cell-penetrating peptide yielded OS4T LNP, boosting delivery efficiency by 12.7-fold over OS4 alone and enabling broad mRNA expression across neurons, astrocytes, microglia, and endothelial cells; validated in orthotopic glioblastoma models, OS4T delivered engineered IL-12 mRNA, suppressing tumor growth and extending median survival to 37 days (vs. 17 days for controls) with minimal systemic toxicity, positioning S4-based LNPs as a robust, translatable platform for CNS-targeted therapeutics.

IAJD-34 is a one-component ionizable amphiphilic Janus dendrimer specifically engineered for targeted mRNA delivery to the lung parenchyma, as described by Meshanni et al. in Nature Communications article "Targeted delivery of TGF-β mRNA to murine lung parenchyma using one-component ionizable amphiphilic Janus Dendrimers" . This synthetic nanoparticle self-assembles with mRNA through simple mixing in acetate buffer, forming stable dendrimersomes approximately 93-97 nm in size with high encapsulation efficiency (>95%) and a positive zeta potential (~48 mV). Its defining feature, highlighted in the study, is exceptional lung tropism after intravenous injection, enabling significantly higher luciferase expression in murine lungs compared to other organs. As demonstrated by Meshanni et al., IAJD 34 effectively delivers therapeutic mRNA (e.g., TGF-β mRNA) to the lower lung, inducing transient protein production with minimal systemic toxicity at appropriate doses (e.g., 10 µg), offering a promising strategy for treating parenchymal lung diseases.

TCL053 is an ionizable amino lipid.1 It has been used in the generation of lipid nanoparticles (LNPs) and has a pKa value of 6.8. LNPs containing TCL053 and encapsulating mRNA encoding the Cas9 nuclease, in combination with LNPs containing TCL053 and encapsulating single-guide RNA (sgRNA) targeting the Rosa26 locus, have been used to induce CRISPR-mediated gene editing in the mouse gastrocnemius muscle.TCL053 is an ionizable lipid that has received FDA approval for preparing mRNA vaccines. It is a three-tailed ionizable lipid to overcome the disadvantage of nonrepeatable administration of AAV vectors. In addition, combined with limb perfusion administration, TCL053 iLNPs could transiently deliver CRISPR-Cas9 mRNA and sgRNA to multiple muscle tissues, reducing immunogenicity and increasing the safety of iLNPs. It is great progress for treating Duchenne muscular dystrophy and other diseases that require multiple doses.

4A3-SCC-PH is a groundbreaking linker-degradable ionizable lipid (LDIL) that features a glutathione (GSH)-responsive cone-shaped molecular structure. This unique architecture enables superior endosomal escape and rapid mRNA release, making it highly effective for mRNA delivery. In vivo studies have highlighted its exceptional performance, showing a 176-fold increase in mRNA delivery efficiency to the liver compared to DLin-MC3-DMA, a widely used benchmark lipid. Both 4A3-SCC-PH and its structural analog, 4A3-SCC-10, also demonstrated significantly enhanced mRNA delivery efficacy compared to their non-disulfide-containing parent compounds and disulfide-containing controls with modified lipid tails.

Si5-N14 is a lipid-based molecule engineered with siloxane groups, designed specifically for efficient mRNA delivery to the lungs. The incorporation of siloxane units boosts the cellular uptake of mRNA-loaded lipid nanoparticles (LNPs) and enhances their ability to escape from endosomes. These properties significantly increase the overall effectiveness of mRNA delivery, making Si5-N14 a promising tool for targeted therapeutic applications.

514O6,10 is an ionizable lipidoid. 514O6,10 formulated LNPs facilitate mRNA delivery to the pancreas.

5A2-SC8 is a dendrimer for miRNA delivery to late-stage liver tumors with low hepatotoxicity. 5A2-SC8 shows potent EC50 < 0.02 mg/kg (siRNA against FVII (siFVII)) in dose-response experiments, and well tolerated in separate toxicity studies in chronically ill mice bearing MYC-driven tumors. 5A2-SC8 is a degradable lipid-like compound (ester-based dendrimer) for small RNAs delivery.5A2-SC8, was obtained by screening a large library of more than 1500 ester-based dendrimers containing ionizable amino groups, which have three tertiary amine heads and five lipid tails. Based on this library, the in vitro transfection efficiency of different formulations of 5A2-SC8 iLNPs was evaluated, discovering the optimal formulation (5A2-SC8, DOPE, cholesterol, PEG at a molar ratio of 15:15:30:3) of 5A2-SC8 iLNPs for delivering fumarylacetoacetate hydrolase (FAH) mRNA to liver.After the intravenous injection via tail, the model mice of hepatorenal tyrosinemia type I had strong FAH protein expression, which prevented body weight loss and increased the survival rate of hepatorenal tyrosinemia mice . In addition to introducing utility of 5A2-SC8 iLNPs for the therapeutic intervention, the 5A2-SC8 iLNPs containing DOTAP have been used to establish complex mouse models via intravenous injection, including in situ liverspecific cancer model and in situ lung-specific cancer model. Based on this iLNPs delivery system, 5A2-SC8 induced model construction method overcomes the time-consuming and costly disadvantages of traditional animal models establishing methods, including transgenesis and gene engineering in embryonic stem cells.

98N12-5 is an ionizable cationic lipid. It has been used in combination with other lipids in the generation of lipid nanoparticles (LNPs). LNPs containing 98N12-5 and encapsulating proprotein convertase subtilisin kexin type 9 (PCSK9) siRNA selectively accumulate in the liver and reduce total serum cholesterol levels in mice and rats and serum LDL levels in cynomolgus monkeys.

DLin-KC2-DMA is a highly potent ionizable lipid used in the formulation of lipid nanoparticles (LNPs) for the delivery of siRNA. It represents a significant advancement over earlier generations of lipids, such as DLin-DMA, due to its dramatically improved gene silencing efficiency.

DLin-KC3-DMA, a nucleic acid, shows in vivo silencing activity. DLin-K-C3-DMA can be used in the synthesis of nucleic acid-lipid particle to delivery of nucleic acid.

503O13 is a next-generation, biodegradable lipid nanoparticle (LNP) engineered for highly efficient and targeted siRNA delivery. Designed through rational structure-activity criteria—including optimal tail length (O13), tertiary amines, and a surface pKa ≥5.5—this single-component LNP achieves unparalleled gene silencing with an ultra-low EC50 of 0.01 mg/kg in preclinical models.503O13 outperforms non-degradable counterparts (e.g., C12-200) with improved toxicity profiles—no hepatic necrosis or pancreatic inflammation—while maintaining rapid blood clearance (t1/2: 6 min) and organ-specific accumulation (liver/spleen).

L-369 (Lipid 369,L369) is novel class of ionizable lipid for siRNA delivery with improved in vivo elimination profile with excellent translation across species,including NHP, wide safety margin.

306Oi10 is a branched-chain ionizable lipidoid that has shown significant promise in the generation of lipid nanoparticles (LNPs) for mRNA delivery. Its unique structural and functional properties make it a highly efficient delivery vehicle for mRNA-based therapeutics.

C24 is a novel multiprotic ionizable lipid. C24 lipid nanoparticle (LNP) has a multistage protonation behavior resulting in greater endosomal protonation and greater translation compared to the standard reference MC3 LNP. C24 LNP also lower injection site inflammation and higher stability compared to MC3 LNP.

246C10 is a synthesized ionizable lipid. 246C10 can be formulated into lipid nanoparticles (LNPs) with dioleoylphosphatidylethanolamine (DOPE), cholesterol, and C16-PEG2000 ceramide (PEG-lipid) as well as mRNA. The lipid nanoparticle formulations can be used for mRNA delivery. To obtain iLNPs that could specifically target liver sinusoidal endothelial cells (LSECs), six different ionizable lipids (241C10 to 246C10) were synthesized by an epoxide ring-opening reaction with piperazine- or piperidine-containing amines. Biodistribution and gene regulation of various iLNPs were assessed in vivo, and the results showed that the 246C10 iLNPs (containing piperazine amine) had the highest luciferase expression in the liver. When further analyzing the 246C10 iLNPs transfection efficiency in different types of liver cells, it was found that tdTomato fluorescence was mainly concentrated in hepatocytes, not in LSECs. Figure 6f shows that 80% of hepatocytes are fluorescent, 40% of LSECs are fluorescent, and 20% of Kupffer cells are fluorescent. Due to the mannose receptor on LSECs, mannose-PEG lipid was introduced into 246C10 iLNPs to alter the distribution of iLNPs in different liver cells. As shown in Figure 6g, tdTomato fluorescence distribution was 15% of hepatocytes, 70% of LSECs, and 15% of Kupffer cells, significantly improved the ability of iLNPs to actively target LSECs. In contrast, this work indirectly shows that the iLNPs with piperazine head lipid are more able to deliver mRNA to the liver and translate the target protein than the iLNPs with piperidine head lipid. It is worth mentioning that the preparation buffer of 246C10 iLNPs could influence the encapsulation efficiency of mRNA. With the addition of sodium chloride in the citrate buffer, the encapsulation efficiency of CRISPR-Cas9 mRNA and sgRNA was increased. These iLNPs were able to treat hemophilia safely, without causing hepatotoxicity, the immune response induced by Cas9 and off-target editing.

TNT-b10 is a novel Lipid-like compound suitable for delivery of siRNA and mRNA both in vitro and in vivo TNT-b10 LLNs was more than 10-fold more potent than TNT-a10 LLNs formulated under the same condition.

Lipid A6 is an ionizable cationic and biodegradable alkyne lipid (pKa = 6.65).It has been used with other lipids in the formation of lipid nanoparticles (LNPs) for the delivery of mRNA. LNPs containing lipid A6 and encapsulating mRNA encoding human erythropoietin (EPO) increase and then maintain homeostatic levels of hemoglobin in the blood in an adenine-induced mouse model of renal anemia.

Lipid 331 is a biodegradable cyclic ionizable lipid. LNPs containing Lipid 331 result in robust transfection in the nasal and lung tissues of mice and efficient transfection of lung epithelial cells and lung-resident APCs. Lipid 331 is a promising candidate for mRNA vaccine delivery, offering the potential for further enhancing the potency of mRNA vaccines.

L202 is an ionizable lipid designed for mRNA vaccines, featuring a pH-responsive N-methylpiperidine head and a unique branched-tail structure with ester linkages to enable biodegradability. With a pKa of ~6.04–6.29, it facilitates efficient endosomal escape while maintaining stability in physiological conditions. Formulated into lipid nanoparticles (LNPs) of ~103 nm (PDI 0.08), L202 achieves >97% mRNA encapsulation efficiency. Its optimized structure drives robust immunogenicity: in mice, a single 0.1–10 μg dose induced dose-dependent SARS-CoV-2 spike-specific IgG titers, outperforming MC3-based LNPs and protein-alum vaccines. L202-LNPs elicited balanced Th1/Th2 responses (IgG2a/IgG1 ratio) and potent germinal center B cell activation, critical for durable immunity. Lyophilization with 16% sucrose preserved mRNA integrity and immunogenicity after 1-month storage at 5°C or 25°C, addressing cold-chain limitations. In nonhuman primates, two 100-μg doses generated neutralizing antibody titers exceeding convalescent human sera, with broad efficacy against Alpha, Beta, Gamma, and Delta variants. Rapid tissue clearance (72 hours post-injection) and minimal hepatic accumulation, attributed to ester hydrolysis, enhanced safety profiles. Additionally, L202-LNPs functioned as intrinsic adjuvants, amplifying protein vaccine responses. Combined with its lyophilization compatibility, potent cross-variant immunity, and favorable pharmacokinetics, L202 represents a promising platform for next-generation mRNA vaccines.

L319 (LIPID 319) is a novel ionizable, biodegradable lipid for delivery of short interfering RNAs (siRNAs). L319-LPN displays rapid elimination with pKa of 6.38 and also shows well tolerated up to 10 mg/kg.

LIPID 14 is a novel ionizable lipid used for mRNA delivery.In 2021, Elia et al. used lipid 2 LNPs and lipid 14 LNPs to deliver mRNA encoding SARSCoV-2 human Fc-conjugated receptor binding domain (RBDhFc mRNA). While both lipid 274 LNP RBD-hFc mRNA and lipid 14 LNP RBD-hFc mRNA induced equal cellular and humoral responses in mice at an mRNA dose of 5 μg, only lipid 14 LNP RBD-hFc mRNA exhibited strong immunogenicity following intradermal administration. Both intradermal administration and intramuscular administration of lipid 14 LNPs could activate antigen presenting cells (APCs), thus inducing cellular responses.