SWITZERLAND – Roche has released results for its haemophilia A therapy candidate, Hemlibra which confirm that its has a favorable safety profile.

In the analysis, no new safety signals were identified with long-term Hemlibra treatment in adults and adolescents with haemophilia A having inhibitors to factor VIII, the clotting protein that is missing or defective in people with haemophilia A.

STASEY study data were presented at the virtual International Society on Thrombosis and Haemostasis (ISTH) 2021 Congress, held from 17-21 July 2021.

Final analysis of the STASEY study included data from 193 people with haemophilia A with factor VIII inhibitors, who received Hemlibra prophylaxis once-weekly for up to two years.

The analysis did not show any new cases of thrombotic microangiopathy or serious thrombotic events (adverse events that have been observed in people with bleeding disorders) related to Hemlibra.

Most common adverse events occurring in 10% or more of people in the STASEY study were joint pain, common cold symptoms, headache, injection site reaction and fever.

In addition, the STASEY study reinforced that Hemlibra is associated with a low incidence of anti-drug antibody (ADA) development.

Ten participants (5.2%) tested positive for ADAs, five (2.6%) of whom were classified as having ADAs that were neutralising in vitro.

In all ten participants, ADA development did not affect the efficacy or safety of Hemlibra; none of the participants had ADAs that resulted in a decrease in Hemlibra plasma concentration, and none of the ADA-positive participants experienced a treated bleed.

In addition, the ADAs disappeared over time, as all study participants tested negative for ADAs at their last visit.

Hemlibra also continued to demonstrate effective bleed control in the STASEY study, with 82.6% of participants experiencing no bleeding episodes that required treatment.

Annualized bleeding rates were consistent with previously reported observations from the pivotal HAVEN studies.

Hemlibra is approved to treat people with haemophilia A with factor VIII inhibitors in more than 100 countries worldwide and people with haemophilia A without factor VIII inhibitors in more than 80 countries worldwide, including the US, EU and Japan.

The drug has been studied in one of the largest clinical trial programmes in haemophilia A with and without factor VIII inhibitors, including eight phase III studies.

Haemophilia A drug market has been on a steady growth rise with the Food and Drug Association recently approving ASC Therapeutics’ request to open a clinical trial in the US for early efficacy of its drug ASC618.

The FDA previously designated ASC618 an orphan drug as a possible treatment for hemophilia A with the intention of providing regulatory support and financial benefits to accelerate the therapy’s clinical development and review.

Preclinical studies showed that the optimized F8 version in ASC618 increased the levels of blood clotting factor VIII (FVIII), which is missing in hemophilia A patients.

It also did so at doses significantly lower than those used for gene therapies delivering the natural F8 version and currently being tested in clinical trials.