The make-or-break FDA advisory panel meeting on rimonabant (Acomplia / Zimulti) got underway on June 13th with a presentation on how independent experts attempted to sort-out and evaluate incidents of "suicidality" that occurred among participants in the clinical trials of the diet drug.

Dr. Eric Coleman, FDA deputy director, said at the outset of the day-long hearing that the relationship between rimonabant, depression and suicide has been "a big concern for us."

Dr. Kelly Posner of the New York State Psychiatric Institute told the panel that a major challenge in assessing the number of incidents of suicidality that occurred during the trial was the wide variation that occurred from medical center to center in how patient incidents were reported.

At the FDA's request, independent researchers went back through data collected by the drug's developer, Sanofi-Aventis, in an effort to further identify events that might have been missed, and also to weed out incidents that had been reported but which might not have been significant.

"We found more suicidal events over all, but fewer events were labeled suicide attempts," Dr. Posner told the panel. Other events, she said, involved "suicidal ideation," which she explained as "thoughts of wanting to be dead . . . or wanting to end one's life."

The day-long meeting, which will air concerns raised about "rimonabant and increased rates of psychiatric adverse events, including depression and suicidality, and neurological adverse events, including seizures," will see members of the committee vote on a variety of recommendations to the FDA.

As an indication of the level of Sanofi's concern over findings by the FDA staff on the issue of suicidality and the possible link of rimonabant to seizures, the company brought eight outside experts in psychiatry and neurology wilth it to the hearing.

The recommendations of members of the FDA's Endocrinologic and Metabologic Advisory Committee are expected to weigh heavily on the decision of the FDA, expected in late July, whether to approve marketing of Zimulti in the United States.