For the second time in a month, Biogen Idec has revealed that it faces a delay in getting US approval for one of its haemophilia treatments.

This time, the US Food and Drug Administration has extended its review of Alprolix, the company’s investigational long-lasting recombinant factor IX Fc fusion protein by three months. The drug is being developed with Swedish Orphan Biovitrum and the delay comes after the agency asked Biogen for more information about the manufacturing process.

No precise Prescription Drug User Fee Act (PDUFA) date was given and the news comes three weeks after the FDA asked for more information about a new haemophilia A drug from Biogen and Sobi, namely Eloctate (recombinant factor VIII Fc fusion protein). That request was also concerning production of the treatment.

Sobi noted that the delay in the USA does not affect the review of Alprolix by the regulatory authorities in Europe.The drug has also been filed in several countries, including Canada, Australia and Japan.

Haemophilia B occurs in about one in 25,000 male births annually, and more rarely in females, affecting about 3,000 people in the USA. It is caused by having substantially reduced or no factor IX activity, which is needed for normal blood clotting.