PB0216 - Efficacy, effectiveness, and safety of extended half-life factor VIII products for the treatment of hemophilia A: protocol of a systematic review

Background: The treatment of people with hemophilia A (PwHA) consists of replacing the deficient clotting factor with factor VIII (FVIII) products, intravenously infused either as prophylaxis (to avoid bleedings) or on-demand (after a bleeding episode). Until recently, frequent infusions were required to reach and maintain the desirable plasma FVIII-clotting activity, due to its pharmacokinetics. Extended half-life (EHL) products were developed to provide a more flexible posology.

Aims: To evaluate the efficacy, effectiveness, and safety of EHL-FVIII for the treatment of PwHA.

Methods: The systematic review was approved by PROSPERO (CRD42021281642) and is being conducted using the PRISMA 2020 statement. Structured search strategies were performed in the PubMed, Embase, Cochrane Library, LILACS, and CRD databases, validated in sequence through the Epistemonikos database and Google Scholar. No language nor publication period were used as restrictions. Randomized controlled trials, non-randomized controlled trials, and observational studies (prospective cohort, retrospective cohort, and cross-sectional) that evaluated the prophylaxis with EHL-FVIII in PwHA compared with standard half-life FVIII or other EHL-FVIII are being included. Two independent reviewers will select the articles and extract the data using standardized forms. Disagreement will be resolved by a third reviewer. The methodological quality assessment tools will be adopted according to the specific research design of each included study. Likewise, the certainty of the evidence will also be evaluated, using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool (Image 1).

Results: A total of 6,068 articles were retrieved in the initial search. After excluding duplicates, 4,999 articles are under evaluation. We expect this review will be complete by the date of the congress.

Conclusion(s): It is expected that our findings will contribute to filling a knowledge gap regarding the EHL-FVIII products for prophylaxis in PwHA.