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Rational design of cationic lipids for siRNA delivery

Abstract

We adopted a rational approach to design cationic lipids for use in formulations to deliver small interfering RNA (siRNA). Starting with the ionizable cationic lipid 1,2-dilinoleyloxy-3-dimethylaminopropane (DLinDMA), a key lipid component of stable nucleic acid lipid particles (SNALP) as a benchmark, we used the proposed in vivo mechanism of action of ionizable cationic lipids to guide the design of DLinDMA-based lipids with superior delivery capacity. The best-performing lipid recovered after screening (DLin-KC2-DMA) was formulated and characterized in SNALP and demonstrated to have in vivo activity at siRNA doses as low as 0.01 mg/kg in rodents and 0.1 mg/kg in nonhuman primates. To our knowledge, this represents a substantial improvement over previous reports of in vivo endogenous hepatic gene silencing.

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Figure 1: Proposed mechanism of action for membrane disruptive effects of cationic lipids and structural diagram of DLinDMA divided into headgroup, linker and hydrocarbon chain domains.
Figure 2: In vivo evaluation of novel cationic lipids.
Figure 3: Efficacy of KC2-SNALP in rodents and nonhuman primates.

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References

  1. de Fougerolles, A.R. Delivery vehicles for small interfering RNA in vivo. Hum. Gene Ther. 19, 125–132 (2008).

    Article  CAS  PubMed  Google Scholar 

  2. Whitehead, K.A., Langer, R. & Anderson, D.G. Knocking down barriers: advances in siRNA delivery. Nat. Rev. Drug Discov. 8, 129–138 (2009).

    Article  CAS  PubMed  Google Scholar 

  3. Judge, A.D. et al. Confirming the RNAi-mediated mechanism of action of siRNA-based cancer therapeutics in mice. J. Clin. Invest. 119, 661–673 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  4. Judge, A.D. et al. Sequence-dependent stimulation of the mammalian innate immune response by synthetic siRNA. Nat. Biotechnol. 23, 457–462 (2005).

    Article  CAS  PubMed  Google Scholar 

  5. Morrissey, D.V. et al. Potent and persistent in vivo anti-HBV activity of chemically modified siRNAs. Nat. Biotechnol. 23, 1002–1007 (2005).

    Article  CAS  PubMed  Google Scholar 

  6. Zimmermann, T.S. et al. RNAi-mediated gene silencing in non-human primates. Nature 441, 111–114 (2006).

    Article  CAS  PubMed  Google Scholar 

  7. Akinc, A. et al. A combinatorial library of lipid-like materials for delivery of RNAi therapeutics. Nat. Biotechnol. 26, 561–569 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  8. Frank-Kamenetsky, M. et al. Therapeutic RNAi targeting PCSK9 acutely lowers plasma cholesterol in rodents and LDL cholesterol in nonhuman primates. Proc. Natl. Acad. Sci. USA 105, 11915–11920 (2008).

    Article  CAS  PubMed  Google Scholar 

  9. Hafez, I.M., Maurer, N. & Cullis, P.R. On the mechanism whereby cationic lipids promote intracellular delivery of polynucleic acids. Gene Ther. 8, 1188–1196 (2001).

    Article  CAS  PubMed  Google Scholar 

  10. Xu, Y. & Szoka, F.C. Jr. Mechanism of DNA release from cationic liposome/DNA complexes used in cell transfection. Biochemistry 35, 5616–5623 (1996).

    Article  CAS  PubMed  Google Scholar 

  11. Zelphati, O. & Szoka, F.C. Jr. Mechanism of oligonucleotide release from cationic liposomes. Proc. Natl. Acad. Sci. USA 93, 11493–11498 (1996).

    Article  CAS  PubMed  Google Scholar 

  12. Torchilin, V.P. Recent approaches to intracellular delivery of drugs and DNA and organelle targeting. Annu. Rev. Biomed. Eng. 8, 343–375 (2006).

    Article  CAS  PubMed  Google Scholar 

  13. Semple, S.C. et al. Efficient encapsulation of antisense oligonucleotides in lipid vesicles using ionizable aminolipids: formation of novel small multilamellar vesicle structures. Biochim. Biophys. Acta 1510, 152–166 (2001).

    Article  CAS  PubMed  Google Scholar 

  14. Maurer, N. et al. Spontaneous entrapment of polynucleotides upon electrostatic interaction with ethanol-destabilized cationic liposomes. Biophys. J. 80, 2310–2326 (2001).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  15. Heyes, J., Palmer, L., Bremner, K. & Maclachlan, I. Cationic lipid saturation influences intracellular delivery of encapsulated nucleic acids. J. Control. Release 107, 276–287 (2005).

    Article  CAS  PubMed  Google Scholar 

  16. Semple, S.C., Chonn, A. & Cullis, P.R. Interactions of liposomes and lipid-based carrier systems with blood proteins: Relation to clearance behaviour in vivo. Adv. Drug Deliv. Rev. 32, 3–17 (1998).

    Article  CAS  PubMed  Google Scholar 

  17. Bailey, A.L. & Cullis, P.R. Modulation of membrane fusion by asymmetric transbilayer distributions of amino lipids. Biochemistry 33, 12573–12580 (1994).

    Article  CAS  PubMed  Google Scholar 

  18. Cullis, P.R. & de Kruijff, B. The polymorphic phase behaviour of phosphatidylethanolamines of natural and synthetic origin. A 31P NMR study. Biochim. Biophys. Acta 513, 31–42 (1978).

    Article  CAS  PubMed  Google Scholar 

  19. Epand, R.M., Robinson, K.S., Andrews, M.E. & Epand, R.F. Dependence of the bilayer to hexagonal phase transition on amphiphile chain length. Biochemistry 28, 9398–9402 (1989).

    Article  CAS  PubMed  Google Scholar 

  20. Sekijima, Y., Kelly, J.W. & Ikeda, S. Pathogenesis of and therapeutic strategies to ameliorate the transthyretin amyloidoses. Curr. Pharm. Des. 14, 3219–3230 (2008).

    Article  CAS  PubMed  Google Scholar 

  21. Cullis, P.R., Hope, M.J. & Tilcock, C.P. Lipid polymorphism and the roles of lipids in membranes. Chem. Phys. Lipids 40, 127–144 (1986).

    Article  CAS  PubMed  Google Scholar 

  22. Heyes, J., Hall, K., Tailor, V., Lenz, R. & MacLachlan, I. Synthesis and characterization of novel poly(ethylene glycol)-lipid conjugates suitable for use in drug delivery. J. Control. Release 112, 280–290 (2006).

    Article  CAS  PubMed  Google Scholar 

  23. Jeffs, L.B. et al. A scalable, extrusion-free method for efficient liposomal encapsulation of plasmid DNA. Pharm. Res. 22, 362–372 (2005).

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

The authors thank K. McClintock for assistance with animal studies. The authors also thank the Centre for Drug Research and Development at the University of British Columbia for use of the NMR facilities and M. Heller for his expert assistance in setting up the 31P-NMR experiments.

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Authors and Affiliations

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Contributions

J.C., M.A.C., P.R.C., T.D.M., M.J.H. and K.F.W. designed and advised on novel lipids. J.C., K.F.W. and M.S. synthesized novel lipids. M.J.H., T.D.M., J.C., K.F.W., M.M., K.G.R., M.A.M., M.T. and M.J. analyzed and interpreted lipid data. T.D.M., M.J.H. and M.A.T. co-directed novel lipid synthesis and screening program. S.C.S. designed and directed rodent in vivo studies. S.C.S., S.K.K., B.L.M., K.L., M.L.E., M.K., A.P.S., Y.K.T., S.A.B., W.L.C., M.J.W. and E.J.C. generated rodent in vivo data, including Factor VII and tolerability analyses. L.N., V.K., T.B., R.A., Q.C. and D.W.Y.S. developed novel siRNAs targeting TTR. R.A. and A.A. designed and directed NHP in vivo studies. S.C.S., S.K.K., A.A., B.L.M., I.M., A.P.S., Y.K.T., R.A., T.B., D.W. Y. S., S.A.B., J.Q., J.R.D. and A.d.F. analyzed and interpreted in vivo data. B.L.M., K.L., A.P.S., S.K.K., S.C.S. and E.J.C. generated and characterized preformed vesicle formulations with novel lipids. D.S. and C.K.C. developed methods and designed and conducted HPLC lipid analyses of preformed vesicle formulations. E.Y. and L.B.J. prepared SNALP formulations. P.R.C. directed biophysical studies and advised on methods. A.P.S., I.M.H., S.D. and K.W. performed biophysical characterization studies (pKa, NMR, differential scanning calorimetric) of novel lipids and formulations. M.J.H., P.R.C., T.D.M., A.P.S., I.M.H. and K.F.W. analyzed biophysical data. S.C.S., M.J.H., A.A. and P.R.C. co-wrote the manuscript. T.D.M., M.M., M.A.M., M.A.T. and A.D.F. reviewed and edited the manuscript. S.C.S., M.J.H., A.A., P.R.C., I.M. and A.D.F. were responsible for approval of the final draft.

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Correspondence to Sean C Semple or Akin Akinc.

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Competing interests

Authors are employees of Alnylam, Tekmira, or Alcana or receive funding from Alnylam.

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Supplementary Fig. 1, Supplementary Tables 1–4 and Supplementary Syntheses 1 and 2 (PDF 345 kb)

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Semple, S., Akinc, A., Chen, J. et al. Rational design of cationic lipids for siRNA delivery. Nat Biotechnol 28, 172–176 (2010). https://doi.org/10.1038/nbt.1602

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