Sanofi Genzyme and Alnylam Report Positive Results from Ongoing phase 2 Open-Label Extension Study with Investigational RNAi Therapeutic Fitusiran in Patients with Hemophilia A and B With or...

Sanofi Genzyme and Alnylam Report Positive Results from Ongoing phase 2 Open-Label Extension Study with Investigational RNAi Therapeutic Fitusiran in Patients with Hemophilia A and B With or Without Inhibitors

- With up to 20 Months of Dosing, Fitusiran Safety and Tolerability Profile Remains Encouraging -

- Once Monthly, Subcutaneous Fitusiran Achieves Median Annualized Bleeding Rate (ABR) of One for All Patients and Zero for Patients with Inhibitors in Exploratory Post-hoc Analysis -

- New England Journal of Medicine Publishes phase 1 Clinical Results with Fitusiran in Patients with Hemophilia A and B without Inhibitors -

- Alnylam Management to Discuss New Clinical Data in Webcast Conference Call Monday, July 10, at 11:30 a.m. ET -

Paris, France and Cambridge, MA  - July 10, 2017 - Sanofi Genzyme, the specialty care global business unit of Sanofi, and Alnylam Pharmaceuticals, Inc, the leading RNAi therapeutics company, announced today new positive results from the ongoing phase 2 open-label extension (OLE) study with fitusiran in patients with hemophilia A and B, with or without inhibitors (N=33).  These results were presented today in an oral presentation at the International Society on Thrombosis and Haemostasis (ISTH) 2017 Congress, being held from July 8 - 13, 2017 in Berlin, Germany. Fitusiran is an investigational RNAi therapeutic targeting antithrombin (AT) for the treatment of patients with hemophilia A and B, that is designed to lower levels of AT with the goal of promoting sufficient thrombin generation upon activation of the clotting cascade to restore hemostasis and prevent bleeding. The companies also announced that phase 1 clinical trial results demonstrating an encouraging preliminary safety and tolerability profile and initial evidence that monthly subcutaneously administered fitusiran lowered AT levels and increased thrombin generation in patients with hemophilia A and B without inhibitors were published online today and will appear in the September 7, 2017, print issue of The New England Journal of Medicine (NEJM).

The updated clinical results in the fitusiran phase 2 OLE study showed that the safety and tolerability profile of fitusiran remains encouraging, with no thromboembolic events, including during co-administration of replacement factor or bypassing agents. The majority of adverse events (AEs) were mild or moderate in severity, with the most common AEs consisting of transient, mild injection site reactions (ISRs). In addition, once-monthly subcutaneous (SC) administration of fitusiran achieved lowering of AT, increases in thrombin generation, and, in a post-hoc exploratory analysis, reductions in the median estimated annualized bleeding rate (ABR) in patients with and without inhibitors. Based on these results, the companies announced last week the initiation of the ATLAS phase 3 program for fitusiran in patients with hemophilia A and B with or without inhibitors.