Positive Results from Ongoing Phase 2 OLE Studies with Patisiran and Revusiran, in Development for the Treatment of ATTR Amyloidosis

We reported data from our ongoing Phase 2 open-label extension (OLE) studies with patisiran and revusiran, investigational RNAi therapeutics targeting transthyretin (TTR) for the treatment of TTR-mediated amyloidosis (ATTR amyloidosis).

New results from our patisiran Phase 2 OLE study provided continued evidence that patisiran has the potential to halt neuropathy progression in patients with Familial Amyloidotic Polyneuropathy (FAP), as there was a mean increase in modified Neuropathy Impairment Scores (mNIS+7) of only 1.7 points from baseline values after 18 months of treatment. These data compare favorably to an estimated increase in mNIS+7 of 22 to 26 points at 18 months, based upon analysis of historical data sets in untreated FAP patients with similar baseline characteristics. Further, at 18 months, treatment with patisiran was associated with a statistically significant and clinically meaningful increase in sweat gland nerve fiber density, marking first-ever evidence that TTR knockdown by patisiran can potentially have a positive effect on nerve regeneration. Patisiran administration was found to be generally well tolerated in FAP patients out to nearly two years, with minimal drug-related adverse events reported.

Initial data from our revusiran Phase 2 OLE trial showed robust and sustained knockdown of serum TTR and appeared to be generally well tolerated in the majority of patients with TTR cardiac amyloidosis out to 10 months of treatment, which is the longest human dosing experience for a GalNAc-siRNA conjugate reported to date. For patients with an evaluable 6-minute walk distance (6-MWD) measurement at 6 months, the majority exhibited stable performance compared to baseline and no clinically meaningful changes in additional cardiac measures.

We look forward to additional data from the ongoing Phase 2 OLE studies with patisiran and revusiran, and continue to be committed to improving the lives of patients with ATTR amyloidosis through advancement of patisiran, revusiran and ALN-TTRsc02. We are hopeful that these promising RNAi investigational therapeutics have the potential to halt progression in patients with ATTR amyloidosis and provide important treatment options for management of this disease with enormous unmet need.