Alnylam's Givosiran study met primary efficacy endpoint in AHP treatment
Alnylam announced "positive complete results" from the ENVISION Phase 3 study of givosiran, an investigational RNAi therapeutic targeting aminolevulinic acid synthase 1 in development for the treatment of acute hepatic porphyria, or AHP. The full ENVISION results demonstrated a 74% mean and 90% median reduction in the primary endpoint measure of annualized rate of composite attacks in patients on givosiran relative to placebo during the six-month double-blind period. In addition, givosiran achieved statistically significant positive results for five of nine secondary endpoints, with an overall safety and tolerability profile that the company believes is encouraging, especially in this high unmet need disease. Adverse events were reported in 89.6% of givosiran patients and 80.4% of placebo patients; serious adverse events were reported in 20.8% of givosiran patients and 8.7% of placebo patients. Ninety-three of 94% , or 99%, enrolled in the open-label extension period of the study. Based on the ENVISION results, the company plans to complete its rolling submission of a New Drug Application and file a Marketing Authorisation Application in mid-2019.