Sanofi Drops Tiludronate For Osteoporosis

Sanofi has discontinued development of its bisphosphonate drug Skelid(tiludronate) for the additional indication of postmenopausal osteoporosis, after Phase III trials failed to provide convincing evidence of its efficacy. The drug is already approved in more than 60 countries for the treatment of Paget's disease.

Sanofi told the Marketletter that it had now completed four Phase III clinical studies of tiludronate in osteoporosis, two in patients with low bone mass and two in patients with low bone mass but who had also suffered a vertebral fracture. 1,800 patients were enrolled into each of the studies, which were conducted in Europe, North America and Australia, and were randomized to receive either placebo, 50mg tiludronate or 200mg tiludronate once-daily for one week out of every month.

Efficacy Data Not Strong Tiludronate was unable to show any difference from placebo in the incidence of new vertebral fractures, at both doses tested. However, at the 200mg dose, tiludronate did show an improvement over placebo in bone mineral density, but this effect may have been blunted by the fact that the placebo group also showed an increase. The increase on placebo may have been a result of measures within the protocol to ensure that all those enrolled were taking in at least 500mg/day calcium.