Alnylam Pharmaceuticals, Inc. (Nasdaq: ALNY), a leading RNAi therapeutics company, announced today that it has presented new pre-clinical data with ALN-AT3, a subcutaneously administered RNAi therapeutic targeting antithrombin (AT) for the treatment of hemophilia and rare bleeding disorders (RBD), at the 55 th Annual Meeting of the American Society of Hematology (ASH) held December 7 – 10, 2013 in New Orleans. In these new studies, repeat administration of ALN-AT3 was found to be well tolerated in Hemophilia A (HA) mice, with no adverse findings up to dose levels 200 times greater than levels required to achieve 50% AT knockdown. Further, the new studies demonstrate that ALN-AT3 administration achieves complete correction of the activated Partial Thromboplastin Time (aPTT) – an ex vivo measure of blood coagulation that is significantly prolonged in hemophilia – in HA mice. ALN-AT3 is a key program in the company’s “Alnylam 5x15” product strategy, which is aimed at advancing five RNAi therapeutic programs directed toward genetically validated disease targets into clinical development, including programs in advanced stages, by the end of 2015.
“Hemophilia and other rare bleeding disorders are characterized by deficiencies in specific clotting factors that ultimately lead to inadequate thrombin generation and a bleeding diathesis. ALN-AT3 is aimed at correcting these bleeding disorders by knockdown of AT – an endogenous anticoagulant – thus, increasing thrombin generation and improving hemostasis,” said Akshay Vaishnaw, M.D., Ph.D., Executive Vice President and Chief Medical Officer of Alnylam. “These new data presented at ASH demonstrate that repeat administration of ALN-AT3 is well tolerated in animal models of hemophilia, and suggest that our RNAi therapeutic has the potential for a wide therapeutic index in subjects with hemophilia. With MHRA approval of our recently filed CTA, we look forward to the advancement of ALN-AT3 in our Phase I clinical trial that we expect to start in early 2014, with data from hemophilia subjects expected by the end of next year.”