Ipsen shares slide after FDA orders hold on PhIII hemophilia drug trials

Ipsen's ($IPN) big plans for a new hemophilia drug ran into an unexpected road block today. The French biotech says that the FDA ordered a hold on two late-stage studies of IB1001 after its partner, the U.S. biotech Inspiration Biopharmaceuticals, found that patients taking the treatment developed antibodies to a protein in it.

Ipsen noted that no adverse events have been linked to the antibodies, which were generated in response to the Chinese Hamster Ovary protein in the hemophilia therapy. "While this finding may be a potential safety concern, no evidence suggests a change in the current overall clinical benefit and risk profile of IB1001," reported Ipsen.

Ipsen--which owns 40% of Inspiration--announced late last year that it is moving its U.S. headquarters from California to New Jersey and spending $45 million on an R&D upgrade in Massachusetts. Inspiration, meanwhile, announced a move to Kendall Square in Boston as it laid the foundation for the commercial launch of its bleeding disorder drugs.

Shares of Ipsen plunged 11% on the news, which triggered some concerns among analysts that the French company was looking at a minimum six-month delay.  IB1001 was filed for approval in Europe at the end of last year and with the FDA in April.

"We now assume (launch in) the second half of 2013 as the best case if regulatory fears can be assuaged, with the worst case being discontinuation," Cheuvreux analyst Marcel Brand noted, according to a report from Reuters.

- here's the press release
- get the Reuters report

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