21 Apr, 2015 12-Month Clinical Data from Patisiran Phase 2 Open-Label Extension (OLE) Study
We presented initial 12-month clinical data from our ongoing Phase 2 open-label extension (OLE) study with patisiran, an investigational RNAi therapeutic in development for the treatment of transthyretin (TTR)-mediated amyloidosis in patients with familial amyloidotic polyneuropathy (FAP). Study results, presented at the 67th Annual Meeting of the American Academy of Neurology (AAN) being held April 18 – 25, showed a mean 2.5 point decrease in modified Neuropathy Impairment Score (mNIS+7) at 12 months in patients who had reached the 12-month endpoint (N=20) at the time of data cutoff. This decrease in neuropathy progression compares favorably to the 13 to 18 point increase in mNIS+7 at 12 months that can be estimated from the literature in untreated FAP patients with similar baseline characteristics.
In addition, patisiran treatment achieved a sustained mean serum TTR knockdown at the 80% target level for approximately 16 months, with an up to 88% mean knockdown achieved between doses. Patisiran was also found to be generally well tolerated out to 17 months of drug administration, with no drug-related serious adverse events to date; all 27 patients enrolled in the study continue to receive patisiran.
We are very encouraged to see what we believe to be continued evidence for possible halting of neuropathy progression after the first 12 months of treatment. In aggregate, these results are consistent with the therapeutic hypothesis that TTR knockdown has the potential to halt neuropathy progression in patients with FAP. If these results are replicated in a randomized, double-blind, placebo-controlled study, we believe that patisiran could emerge as an important treatment option for patients suffering from this debilitating, progressive and life-threatening disease.