News: CSL UPDATE 2-EU regulator backs use of Pfizer's gene therapy for rare bleeding disorder

(Adds trial data in paragraph 9, patient population in paragraph 11, details and background throughout)

May 31 (Reuters) - The European Medicines Agency (EMA) has recommended the use of Pfizer's PFE.N gene therapy for a rare bleeding disorder called hemophilia B, which typically requires regular infusions of a blood-clotting protein, the regulator said on Friday.

The regulator has recommended granting a 'conditional marketing authorization,' which is for the approval of a medicine addressing unmet medical needs of patients based on less comprehensive data than normally required.

The decision comes months after the one-time therapy received regulatory approvals in the United States and Canada, where it is branded Beqvez.

Any recommendation by the EMA's Committee for Medicinal Products for Human Use (CHMP) has to be formally approved by the European Commission, which usually follows the regulator's decision.

The therapy carries a price tag of $3.5 million in the U.S. - the same as Australian drugmaker CSL Ltd's (CSL) rival gene therapy Hemgenix.

In the EU, it will be sold under the brand name Durveqtix.

People with hemophilia have a fault in a gene that regulates production of proteins called clotting factors, which can cause spontaneous as well as severe bleeding following injuries or surgery. It predominately affects males.

The therapy is designed to stimulate production of the protein, called factor IX (FIX), by the patient's own body instead of intravenous infusions of FIX multiple times a week or a month.

The recommendation comes based on a late-stage trial in which a single dose of the therapy was shown to work as well as standard-of-care protein infusions after a year, with bleeding completely eliminated in 60% of patients versus 29% who received infusions.

Pfizer said it will continue to monitor for long-term durability and safety of the treatment over the course of 15 years.

More than 38,000 people worldwide are living with hemophilia B, said Pfizer, citing the World Federation of Hemophilia.