Pfizer and Sangamo recently announced that the first patient has been dosed in the Phase 3 AFFINE (efficAcy and saFety Factor vIii geNe thErapy) study of giroctocogene fitelparvovec (SB-525), an investigational hemophilia A gene therapy. Giroctocogene fitelparvovec is developed using recombinant adeno-associated viruses (AAVs) as vectors to deliver the genetic codes that illicit factor VIII (FVIII) production in hemophilia A patients. These AAVs deliver the modified genetic material into an individual's liver cells without causing disease or triggering significant immune responses.
According a Pfizer press release AFFINE is a multicenter, single arm study that will evaluate the efficacy and safety of giroctocogene fitelparvovec in patients with moderately severe to severe hemophilia A. A primary measure of the therapy's efficacy will be its impact on annual bleed rate (ABR) through 12 months following treatment, when compared to ABR on FVIII replacement therapy collected in the lead-in study period. Trial participants will be evaluated for a five-year period post infusion to further assess the therapy's durability and efficacy.
“The initiation of the pivotal Phase 3 dosing study of giroctocogene fitelparvovec is a significant achievement for Pfizer as we continue our longstanding commitment to improving care for the hemophilia community,” said Brenda Cooperstone, Chief Development Officer, Rare Disease, Pfizer Global Product Development. “Enrollment in the lead-in study is progressing well and recruitment is on track for Phase 3. Given the Phase 1/2 study findings to date, we believe that giroctocogene fitelparvovec has the potential to sustain factor levels and reduce annual bleed rates, suggesting this one-time gene therapy could potentially transform the standard of care for eligible patients worldwide.”
Source: Pfizer press release dated October 7, 2020