Just a few days after picking up its first approval for haemophilia A drug Hemlibra, Roche has reported new data that could expand the drug’s eligible patient population.
Hemlibra (emicizumab-kxwh) got the nod from the US FDA last week to prevent or reduce the frequency of bleeding episodes in patients with haemophilia A who have developed inhibitors to Factor VIII, an indication currently under review by the EMA. Now, data from the phase III HAVEN 3 trial show that the drug was able to significantly reduce bleeds in haemophilia A patients without those inhibitors.
The study met its primary endpoint, showing a significant and clinically meaningful reduction in the number of treated bleeds over time in people receiving Hemlibra prophylaxis every week compared to those receiving no prophylaxis. According to Roche, data comparing the drug’s performance in patients who have previously received factor VIII prophylaxis also suggested its drug was superior when it came to reducing bleeds requiring treatment.
The data have yet to be subjected to scrutiny by physicians but according to Roche will be used to filed for expanded approval of Hemlibra. The rapid progression with the drug lends further weight to the view that the company could have a blockbuster on its hands, with consensus analyst predictions putting sales of the drug around $1.5bn at peak, and some suggesting it could go even higher.
“Hemlibra is the first product to show superior efficacy to factor VIII prophylaxis,” commented Sandra Horning, Roche’s chief medical officer. “We look forward to working with health authorities to make this treatment available for all people with haemophilia A as soon as possible.”
Hemlibra was approved in the US on the basis of the HAVEN 1 and 2 studies, which showed an 87% reduction in treated bleeds, and a 79% cut treated bleeds compared to previous treatment with bypassing agent. It is billed as a first-in-class therapy that works by bridging other factors in the blood (activated factor IX and factor X) to restore blood clotting and the first new medicine for haemophilia A patients with inhibitors in almost two decades.
Among people with severe haemophilia A, about 30% will develop inhibitors but the proportion is much lower with mild and moderate haemophilia A at about 9%, according to figures from The Haemophilia Society. Approval in haemophilia A without inhibitors would therefore significantly expand the number of patients eligible for treatment with Roche’s drug.
“It is well established that prophylaxis is the preferred approach for treatment of haemophilia A, but this can require frequent intravenous infusions, and some patients on prophylaxis can still experience bleeds, while others prefer on-demand treatment,” said Johnny Mahlangu of the University of the Witwatersrand in South Africa, one of the HAVEN 3 investigators.
“Given its potential to be dosed through subcutaneous injection only once weekly or every other week, Hemlibra may provide a further effective prophylactic treatment option for more people with haemophilia A and help alleviate some of the administration burden associated with current treatment.”
Haemophilia A treatment is being transformed by a series of long-acting Factor VIII products such as Biogen’s Eloctate, Shire’s Adynovate, Bayer’s Kovaltry and CSLBehring’s Afstyla, which are generally dosed two or three times a week rather than every other day as with older drugs. Novo Nordisk is developing a once-weekly version of its established NovoEight product – called N8-GP – that could be filed next year.
Market research firm GlobalData recently predicted that emicizumab will capture a sizeable chunk of the market in both the inhibitor and non-inhibitor haemophilia A market segments, thanks to greater dosing convenience, bringing in $2.6bn by 2026.