fizer has got the thumbs-up from regulators in Europe for the investigational osteoporosis compound Fablyn.

Fablyn (lasofoxifene) has been approved by the European Commission for the treatment of osteoporosis in post-menopausal women at increased risk of fracture. The drug, a selective oestrogen receptor modulator like Eli Liily’s Evista (raloxifene), has been developed using technology from Pfizer’s partner Ligand Pharmaceuticals.

John Higgins, Ligand’s chief executive, said the European approval of Fablyn marks the fourth drug associated with his firm’s research platform that has been approved “and the second to be approved in just the past six months”. The approval has triggered a $3 million milestone payment which will be made in the form of Pfizer returning around a third of the stake it already holds in Ligand to the San Diego-based firm. The latter is also entitled to royalties.

Pfizer is responsible for the registration and worldwide marketing of Fablyn but in Europe at least, the company is expected to sign up a licensing partner to sell the drug. However, it is not clear whether the European approval will be reflecting in a similar green light being granted in the USA just yet.

Two months ago, the US Food and Drug Administration issued a complete response letter asking for additional information on Pfizer’s application for lasofoxifene. This came just a few months after the agency’s Advisory Committee for Reproductive Health Drugs voted 9-3 that the benefits of the once-daily drug outweigh the risks.

However, that vote was somewhat surprising, seeing as it came after briefing documents from FDA staffers who noted that patients who took the lowest dose of the drug (0.25mg) had a higher incidence of blood clots and deaths compared with the group on placebo.