“Alnylam scientists and collaborators continue to make significant progress with RNAi therapeutics in important areas of unmet medical need. We are encouraged by the data continuing to emerge from our hypercholesterolemia, Ebola, liver cancer, and PML programs which show potent and specific in vivo efficacy mediated by an RNAi mechanism,” said Victor Kotelianski, M.D., Ph.D., Vice President, Research at Alnylam. “We are also excited by our progress in optimizing siRNAs for systemic delivery, including our recent data regarding heart and muscle delivery. We believe that these cumulative data demonstrate Alnylam’s scientific leadership and commitment in translating the science of RNAi into a new class of innovative medicines.”
Hypercholesterolemia
Alnylam is developing a systemically delivered RNAi therapeutic for the treatment of hypercholesterolemia targeting PCSK9, a well-validated gene involved in the metabolism of LDL cholesterol (“bad cholesterol”). In a poster titled “RNAi Therapeutics Targeting PCSK9 Acutely Lower Cholesterol from Mice to Non-Human Primates,” Alnylam scientists presented in vivo data demonstrating that an RNAi therapeutic targeting the PCSK9 gene significantly decreased LDL cholesterol in three pre-clinical animal models – mouse, rat and non-human primate.
Data presented at the meeting from studies in rodent models include the following:
an RNAi therapeutic targeting PCSK9 demonstrated statistically significant dose- dependent silencing of PCSK9 mRNA and lowered total cholesterol by 40 to 50 percent as compared with control, non-specific siRNAs; and, the effects on cholesterol lowering was mediated by a three to five fold increase in LDL receptor levels with no effect on hepatic triglycerides and hepatic cholesterol; these data further support the belief that RNAi therapeutics targeting PCSK9 are unlikely to result in steatosis (fatty liver). In non-human primate models, data presented include the following as compared to a control siRNA:
RNAi-mediated gene silencing was associated with rapid reductions in LDL cholesterol levels by 40 to 60 percent of pre-dose levels; circulating apolipoprotein B (apoB) levels – a constituent of the LDL particle – decreased by 30 to 40 percent of pre-dose levels; after a single intravenous injection, the RNAi therapeutic showed a durable biological effect with levels of LDL cholesterol decreased for up to three weeks; and, therapeutic efficacy was observed with an overall decreased ratio of total cholesterol to HDL cholesterol (“good cholesterol”) – a result which has been shown in humans to correlate with clinical benefit. Liver Cancer
Alnylam is developing a systemically delivered RNAi therapeutic, ALN-VSP, for the treatment of liver cancers and potentially other solid tumors. ALN-VSP comprises two siRNAs in a lipid particle formulation. These two siRNAs target separate genes involved in the growth and development of tumors: kinesin spindle protein, or KSP, and vascular endothelial growth factor, or VEGF. In a talk titled “Translating RNAi,” Muthiah Manoharan, Ph.D., Vice President, Drug Discovery at Alnylam presented in vivo data from its ALN-VSP program which were generated in collaboration with Protiva, using their stable nucleic acid-lipid particles, or SNALP, technology.
Pre-clinical data with ALN-VSP, as compared to a control non-specific siRNA, in a mouse model of liver cancer demonstrated the following: significant dose-dependent silencing of both KSP and VEGF derived from the human tumor; evidence of tumor cell cycle arrest due to KSP silencing documented histologically; reduction in overall tumor growth as measured by quantification of a tumor-specific gene; and marked reduction in the size of liver tumors in VSP-treated animals as observed by gross pathology. Alnylam BioDefenseTM/Ebola
Alnylam is developing an RNAi therapeutic directed against the Ebola virus, which can cause a severe, often fatal infection, and poses a potential biological safety risk and bioterrorism threat. In a poster titled “RNAi Therapeutics for the Treatment of Ebola Virus Infection,” pre-clinical data were presented on this program, which utilizes an optimized RNAi therapeutic formulated in a lipid particle for systemic delivery. This work was done in collaboration with Tekmira using their lipid particle delivery formulation technology.
Pre-clinical data presented include the following: potent siRNAs with in vitro anti-viral activity have been identified against all genes in the Ebola genome; a greater than 95 percent decrease in viral titer was seen when an RNAi therapeutic targeting one of these genes, VP35, was administered to mice infected with Ebola; and, the VP35 siRNA, as compared with a control non-specific siRNA, was able to protect both mice and guinea pigs from lethal Ebola infection. Alnylam is working with the United States Army Medical Research Institute of Infectious Diseases (USAMRIID), an organization which is uniquely experienced in the handling, safety, and security requirements of specialized biological agents. Alnylam produces drug candidates which are then sent to USAMRIID for in vitro and in vivo testing against the Ebola virus. The National Institute of Allergy and Infectious Diseases (NIAID), a component of the National Institutes of Health (NIH), is funding this work through a federal contract (No. HHSN266200600012C).
Progressive Multifocal Leukoencephalopathy (PML)
Alnylam is developing an RNAi therapeutic for the potential treatment of PML, in collaboration with Biogen Idec. PML is caused by infection of the central nervous system with a virus called “JC virus” and can occur in certain immune-suppressed patients, including those receiving immunomodulatory therapies. In a poster titled “Developing RNAi Therapeutics Targeting JCV for Treatment of PML,” Alnylam scientists presented results showing that potential JCV RNAi therapeutic candidates targeting different JCV transcripts have been identified and showed potent inhibition of secondary PML infection in vitro, both prophylactically and post-infection. Because there is no established animal model of PML, Alnylam is delivering its RNAi therapeutic to normal oligodendrocytes, the primary site of JCV infection in vivo.
Additional pre-clinical data presented from this program included the following:
JCV siRNAs are stable in human cerebrospinal fluid (CSF) with half-lives greater than 48 hours, and do not produce unwanted cytokine responses; in a rodent model, siRNAs in vivo were successfully delivered and silenced an endogenous oligodendrocyte target (CNP) in a specific manner as compared with a control non-specific siRNA; direct central nervous system (CNS) delivery of siRNA in the rodent model silenced the CNP mRNA by approximately 75 percent, as compared with a control non-specific siRNA, and was durable for up to one week; CNP silencing was found to be mediated by an RNAi mechanism as measured by 5’RACE; and in a non-human primate model, direct infusion of an siRNA into the CNS silenced the CNP mRNA by 55 percent. Alnylam believes these findings further support the use of RNAi as a potential therapeutic approach for the treatment of PML.
Delivery
“As we continue to develop novel delivery solutions for RNAi therapeutics, we are excited by the new data around chemical modifications for improved efficacy, safety and delivery,” said Muthiah Manoharan, Ph.D., Vice President, Drug Discovery at Alnylam. “In addition, we are also encouraged by the use of simple IntralipidTM formulations using cholesterol-conjugated siRNAs and antagomirs which showed promising muscle delivery. Indeed, these data, with our collaborator Markus Stoffel, suggest an exciting convergence of conjugation and formulation approaches for systemic delivery of RNAi therapeutics.”
In the talk titled “Translating RNAi,” Dr. Manoharan also presented new data related to the effective delivery of RNAi therapeutics. Dr. Manoharan showed that among the numerous carbohydrate modifications to improve the drug-like properties of siRNAs, 2’-Fluoro modifications consistently provided increased target binding affinity, endonuclease stability, and, importantly, reduced immune response. In addition, it is the only modification compared to other carbohydrate modifications, including locked nucleic acid, or LNA, that preserves RISC activity when used in both sense and antisense strands.
Data presented included the following:
2’-Fluoro modified siRNAs are significantly more stable, thermodynamically and to nucleases in biological fluids, and can increase the efficacy of siRNAs approximately 2-fold in vivo; and a 2’-Fluoro modified siRNA targeting Factor VII was found to produce no immuno-stimulatory response, whereas a corresponding unmodified siRNA could stimulate IFN-alpha and TNF-alpha in vitro. Alnylam has exclusive access to the use of 2’-Fluoro chemistries for RNAi therapeutics through its 2004 agreement with Isis Pharmaceuticals, Inc.
In addition, data were presented related to new delivery approaches for the delivery of RNAi therapeutics. Specifically:
a new cationic lipid was developed in collaboration with Tekmira; a substantial increase in potency of siRNA-containing lipid particles containing this lipid was observed suggesting the potential to develop new lipid-based formulations for systemic delivery of siRNAs with markedly improved potency; PEG conjugation can facilitate delivery of siRNAs to the intestine; and Alnylam’s new lipid particle formulations with new cationic lipids and PEG modifications continue to improve the therapeutic potential of siRNAs and antagomirs. Finally, in a talk titled, “RNAi Based Therapy,” Markus Stoffel, M.D., Ph.D., Professor for Metabolic Diseases at the Institute of Molecular Systems Biology, Swiss Federal Institute of Technology in Zurich, member of the Alnylam Scientific Advisory Board and long-term collaborator of Alnylam, presented new data utilizing cholesterol-conjugated siRNAs that are co-formulated with commercially available IntralipidTM. These new cholesterol-conjugated siRNA:Intralipid formulations showed distribution to heart and muscle. Similar results were obtained with single-stranded, cholesterol-conjugated olionucleotides targeting microRNAs, also called “antagomirs,” including silencing of microRNAs in heart and muscle.
About RNA Interference (RNAi)
RNAi is a revolution in biology, representing a breakthrough in understanding how genes are turned on and off in cells, and a completely new approach to drug discovery and development. Its discovery has been heralded as “a major scientific breakthrough that happens once every decade or so,” and represents one of the most promising and rapidly advancing frontiers in biology and drug discovery today, and was awarded the 2006 Nobel Prize for Physiology or Medicine. RNAi is a natural process of gene silencing that occurs in organisms ranging from plants to mammals. By harnessing the natural biological process of RNAi occurring in our cells, the creation of a major new class of medicines, known as RNAi therapeutics, is on the horizon. RNAi therapeutics target the cause of diseases by potently silencing specific messenger RNAs (mRNAs), thereby preventing disease-causing proteins from being made. RNAi therapeutics have the potential to treat disease and help patients in a fundamentally new way.
About Alnylam Pharmaceuticals
Alnylam is a biopharmaceutical company developing novel therapeutics based on RNA interference, or RNAi. The company is applying its therapeutic expertise in RNAi to address significant medical needs, many of which cannot effectively be addressed with small molecules or antibodies, the current major classes of drugs. Alnylam is leading the translation of RNAi as a new class of innovative medicines with peer-reviewed research efforts published in the world’s top scientific journals including Nature, Nature Medicine, and Cell. The company is leveraging these capabilities to build a broad pipeline of RNAi therapeutics; its most advanced program is in Phase II human clinical trials for the treatment of respiratory syncytial virus (RSV) infection. In addition, the company is developing RNAi therapeutics for the treatment of a wide range of disease areas, including hypercholesterolemia, liver cancers, and Huntington’s disease. The company’s leadership position in fundamental patents, technology, and know-how relating to RNAi has enabled it to form major alliances with leading companies including Medtronic, Novartis, Biogen Idec, and Roche. To reflect its outlook for key scientific, clinical, and business initiatives, Alnylam has established “RNAi 2010” which includes the company’s plan to significantly expand the scope of delivery solutions for RNAi therapeutics, have four or more programs in clinical development, and to form four or more new major business collaborations, all by the end of 2010. Alnylam is a joint owner of Regulus Therapeutics LLC, a joint venture focused on the discovery, development, and commercialization of microRNA therapeutics. Founded in 2002, Alnylam maintains headquarters in Cambridge, Massachusetts. For more information, visit www.alnylam.com.
Alnylam Forward-Looking Statements
Various statements in this release concerning Alnylam’s future expectations, plans, and prospects, including its views with respect to the robustness, scope, and predictive value of the data presented at the Keystone Symposium, constitute forward-looking statements for the purposes of the safe harbor provisions under The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by these forward-looking statements as a result of various important factors, including risks related to: Alnylam’s approach to discover and develop novel drugs, which is unproven and may never lead to marketable products; Alnylam’s ability to fund and the results of further pre-clinical and clinical trials; obtaining, maintaining and protecting intellectual property utilized by its products; Alnylam’s ability to enforce its patents against infringers and to defend its patent portfolio against challenges from third parties; Alnylam’s ability to obtain additional funding to support its business activities; Alnylam’s dependence on third parties for development, manufacture, marketing, sales, and distribution of products; the successful development of Alnylam’s product candidates, all of which are in early stages of development; obtaining regulatory approval for products; competition from others using technology similar to Alnylam’s and others developing products for similar uses; Alnylam’s dependence on collaborators; and its short operating history; as well as those risks more fully discussed in the “Risk Factors” section of our most recent report on Form 10-K on file with the Securities and Exchange Commission. In addition, any forward-looking statements represent Alnylam’s views only as of today and should not be relied upon as representing its views as of any subsequent date. Alnylam does not assume any obligation to update any forward-looking statements.
Contact: Investors: Alnylam Pharmaceuticals, Inc. Cynthia Clayton, 617-551-8207 or Media: KMorrisPR Kathryn Morris, 845-635-9828
Source: Alnylam Pharmaceuticals, Inc.
