Personalized Prophylaxis with Human-Cl Recombinant FVIII in HA Patients

Abstract

BackgroundProphylactic therapy aims to maintain sufficient factor VIII (FVIII) plasma levels to prevent bleeding. FVIII plasma trough level and time spent above a certain threshold are mainly determined by the half-life of the FVIII concentrate and the injection interval.AimsA clinical study was conducted to investigate the efficacy of individually PK-tailored prophylaxis with Human-cl rhFVIII.MethodsThis prospective, open-label, multicenter phase 3b study included previously treated immunocompetent adult patients with severe hemophilia A without past or present inhibitors. Each patient started with a PK evaluation (single dose of 60 ± 5 IU/kg) followed by 1-3 months of routine prophylaxis (i.e. 30-40 IU/kg every other day or 3 times per week, Phase I) until individual PK data was analyzed. It was calculated, which dose and injection interval would theoretically result in a trough FVIII level of ≥1%. Then, prophylaxis was continued for 6 months using the individually recommended treatment scheme (Phase II).ResultsThe study enrolled 66 patents from 20 centers across 8 countries. The majority of patients (62.1%) had been treated on-demand only before study entry. Their median annualized bleeding rate (ABR) was 41. Key outcomes of the personalized prophylaxis are: •The prophylactic injection interval was extended from usually 3 times per week in Phase-I to twice per week or less in 58% of patients.•The median dosing interval was 3.5 days.•73% of patients did not experience any bleeding episode.•The mean ABR in phase-II was 1.45 (3.16 in Phase-I).•The median weekly prophylactic dose decreased by nearly 10% compared to Phase-I.•There were no inhibitors and related serious adverse events.ConclusionThe data suggest that personalized prophylaxis with Human-cl rhFVIII results in a more convenient treatment for more than half of the patients with lower factor consumption and a lower ABR while remaining safe and efficacious. DisclosuresKlamroth:Biogen and SOBI: Honoraria, Speakers Bureau; Bayer, Baxter, CSL Behring, Pfizer, Novo Nordisk, and Octapharma: Honoraria, Research Funding, Speakers Bureau. Rusen:Octapharma: Other: Investigator. Walter:Octapharma: Employment. Bichler:Octapharma AG: Employment. Pasi:Biogen, Octapharma, Genzyme, and Pfizer: Consultancy, Honoraria; Octapharma: Research Funding. Tiede:Octapharma: Other: Investigator, Speakers Bureau; Leo Pharma: Consultancy, Honoraria; SOBI: Consultancy, Honoraria; Boehringer Ingelheim: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Novo Nordisk: Consultancy, Honoraria, Research Funding; CSL Behring: Consultancy, Honoraria, Research Funding; Biogen Idec: Consultancy, Honoraria; Biotest: Consultancy, Honoraria, Research Funding; Bayer: Consultancy, Honoraria, Investigator, Research Funding; Baxter: Consultancy, Honoraria, Research Funding; Coachrom: Research Funding. Knaub:Octapharma: Employment.