The race to develop better treatments for the clotting disorder hemophilia A is getting more heated by the day, with the list of companies vying for a market-leading position including such big names as Roche, Spark, Shire and Alnylam. Roche picked up FDA approval in November for its drug Hemlibra (emicizumab)—and now it has taken a big step forward in Europe, where the product is under regulatory review.
The Medicines and Healthcare Regulatory Agency in the U.K. granted a positive opinion under its early-access program for Hemlibra to prevent bleeding episodes in patients with hemophilia A. The early-access opinions are meant to provide guidance to physicians in the U.K. who might want to prescribe drugs before they obtain regulatory approval there.
The agency’s opinion was based on data from the company’s phase 3 program, Haven, according to a public report (PDF) it issued. It also cited the high unmet need for more effective treatments for hemophilia A in the U.K. The disease is often treated with drugs that replace coagulation factor VIII (FVIII), but these treatments fail in up to 40% of patients, according to the agency. Patients who develop FVIII inhibitors can be treated with so-called bypassing agents, but they have to be administered frequently and are often ineffective.
Expectations for Hemlibra have been high ever since the FDA gave Roche breakthrough therapy designation for the drug in 2015, but the path to approval has been anything but easy. Data from the pivotal trial showed an 87% reduction in bleeding episodes. But there were some non-responders, and some patients suffered thromboembolic side effects. Although the FDA approved the drug a full three months earlier than expected, it required Roche to include a boxed warning on the label explaining that Hemlibra can cause dangerous blood clots when used with bypassing agents, specifically Shire’s Feiba.
Roche had cited repeated dosing of bypassing agents like Feiba as the cause of the adverse events seen in its phase 3 program, raising the hackles of Shire, which obtained a preliminary injunction last year meant to stop Roche from making “inaccurate and misleading” statements. Shire is looking to protect its own hemophilia franchise, which includes treatments it picked up in 2016 in a $32 billion acquisition of Baxalta. In September, the Court of Hamburg reviewed evidence from both companies and concluded Roche had not acted inappropriately. Shire withdrew its complaint.
But Shire is far from the only competitor Roche will need to contend with as it moves forward in hemophilia. RNAi specialist Alnylam restarted its trials of fitusiran to treat hemophilia A in December after the FDA lifted a clinical hold so the company could develop a strategy to improve safety monitoring. Spark Therapeutics—which recently gained acclaim for winning FDA approval of its gene therapy to treat a rare form of blindness—is in phase 2 trials of a gene therapy treatment for hemophilia A. And California-based BioMarin Pharmaceutical announced in December that it has enrolled the first patient in a phase 3 trial of its gene therapy to treat the disease.
Still, investors' hopes remain high for Roche’s Hemlibra. Analysts on average expect the product to eventually be pulling in $2 billion in sales per year. Analysts at Jefferies have are even more optimistic, projecting an ambitious $5 billion a year for the product.