30 Jun, 2020 New 12-Month Interim Data From the ENVISION Phase 3 Study of Givosiran in Acute Hepatic Porphyria
Interim results from the open-label extension (OLE) period of the ENVISION Phase 3 study of GIVLAARI® (givosiran) in acute hepatic porphyria (AHP) were presented by study investigator Eliane Sardh, M.D., Ph.D. during a webinar hosted by Alnylam, demonstrating sustained efficacy and acceptable safety through 12 months of treatment, with evidence for potentially improved efficacy over time.
In an interim analysis of the OLE period (6-12 months) of the ENVISION Phase 3 study, patients with acute hepatic porphyria (AHP) who continued on GIVLAARI treatment experienced sustained reduction in the annualized rate of composite porphyria attacks (AAR), with a median AAR of 0.0 and over 60% of patients attack-free. Furthermore, sustained lowering of aminolevulinic acid and porphobilinogen—the toxic heme synthesis intermediates believed to be causal for the disease manifestations of AHP—was accompanied by durable reductions in hemin use, lower levels of patient-reported daily worst pain and ongoing improvements in patient-reported quality of life and ability to function. The safety profile of GIVLAARI was consistent with that observed in the double-blind period of the study, and there were no new safety findings.