FDA staff note deaths in Pfizer bone drug study

amplify image

Drugstore. File Photo: EFE

A higher percentage of patients treated with an experimental Pfizer Inc drug for osteoporosis died during a clinical trial compared with a placebo, U.S. drug reviewers said in an analysis released on Thursday.

The higher proportion of deaths through five years was statistically significant only for the lowest dose of the drug called Fablyn, said Food and Drug Administration reviewers.

More patients given Fablyn, which was co-developed with Ligand Pharmaceuticals Inc, also developed blood clots. The FDA staff said Fablyn was effective for preventing fractures and they would ask an advisory panel due to meet on Monday if the drug's overall safety were acceptable.

Pfizer, in a separate summary, said "overall (Fablyn) was not associated with an increased mortality risk." The higher rate seen for the low-dose patients "appears to be due to an unusually low mortality rate in the placebo group" in people treated in Mexico, Central and South America, Pfizer said.

Nearly 80 percent of patients were in other regions. The causes of death were consistent with the leading killers of elderly people, including cancer and heart disease, Pfizer said. Pfizer shares fell 0.5 percent to $19.10 in morning trading on the New York Stock Exchange, while Ligand shares fell 0.6 percent to $3.32 on Nasdaq.