Through a series of abstracts and oral presentations at the recent 2019 Congress of the International Society on Thrombosis and Haemostasis (ISTH), Genentech, a member of the Roche Group, announced new trial data on Hemlibra®. The therapy is laboratory-engineered to perform a key function in the clotting cascade that is normally carried out by the same factor VIII (FVIII) protein that is deficient in individuals with hemophilia A.
The “cascade” is a series of chemical and molecular reactions between clotting factors that ensure the formation of a viable clot. In this case, the Hemlibra® protein binds to and bridges two other key clotting proteins, activated factor IX and factor X, important components of the cascade normally performed by FVIII. It is also unique in that is administered subcutaneously, not infused intravenously the way factor replacement products are typically delivered.
Much of the data presented at ISTH, which was held July 6-10 in Melbourne, Australia, was gleaned from the HAVEN clinical trial program. The program was designed to assess the efficacy and safety of Hemlibra® in people with and without FVIII inhibitors. According to a Genentech press release, the HAVEN studies were also meant to measure its potential to help “overcome current clinical challenges” such as the short-lasting effects of existing treatments, the development of FVIII inhibitors and the need for frequent venous access.
Results from HAVEN showed that a high proportion of patients experienced zero bleeds requiring additional treatment while on Hemlibra®, which was maintained over a median of 83 weeks. Across all four HAVEN studies, more than 87% of participants experienced zero joint bleeds (spontaneous or injury/trauma induced) necessitating an infusion of factor. Further, HAVEN data demonstrated that Hemlibra® prophylaxis offers a “clinically meaningful” improvement in long-term health-related quality of life, versus previous episodic or prophylactic FVIII treatment for hemophilia A patients both with and without FVIII inhibitors. Improvements in quality of life (QOL) were captured via self-reported questionnaires which gleaned certain QOL measurements such as reductions in missed days of work after starting on Hemlibra® therapy.
A separate phase IIIb study known as STASEY, examined Hemlibra® as it relates to safety, efficacy and health-related quality of life in people with hemophilia A with FVIII inhibitors. The results showed that adverse events (AEs) occurred in 20.5% of the 88 trial participants. The most common AEs were injection site reactions, joint pain, headache and common cold symptoms. There was one serious AE reported, a catheter site abscess. In addition, 80.7% of the patients in this study arm did not experience a bleed that necessitated treatment with a factor replacement therapy. Lastly, the data presented at ISTH revealed no new safety signals and reinforced the safety profile for Hemlibra® seen in the pivotal HAVEN 1 trial.
Source: Genentech press release dated July 8, 2019