Panel Dismisses Etidronate Osteoporosis Claim

A US Food and Drug Administration advisory committee has concluded that there is no convincing evidence that Procter & Gamble's bisphosphonate product Didrocal (etidronate/ calcium carbonate) significantly helps prevent fractures in high-risk osteoporosis patients. This is the second time that the panel has reviewed the drug for this indication. However, some doctors say they will keep on prescribing the drug, which is already available as Didronel for Paget's disease.

The panel evaluated data from various P&G studies of the drug, which suggested that severely-affected patients were twice as likely to go three years without having a bone fracture when they took the drug compared to those who received calcium supplementation. While the data presented did show that the drug increased bone mass and appeared to help the high-risk subgroup, the panel questioned why during some years these patients actually had more fractures, and concluded that there was not enough evidence to approve the supplemental indication without a prospective study.

It appears that, overall, the panel were satisfied about the safety of the drug and were agreed that a trend seen in previous data sets which suggested an increase in the risk of vertebral fractures in the third year of treatment was not supported by the current five-year data. However, the committee took issue with the fact that the new data suggested efficacy in a narrower range of patients than were actually included in the indication.