PROZAC ADR DATA DOES NOT SUPPORT CAUSAL RELATIONSHIP TO SUICIDAL THINKING

PROZAC ADR DATA DOES NOT SUPPORT CAUSAL RELATIONSHIP TO SUICIDAL THINKING, FDA Center for Drug Evaluation and Research Deputy Director Gerald Meyer said in a July 26 letter to the Citizens Commission on Human Rights (CCHR), denying the group's petition to withdraw approval of Lilly's antidepressant. "The data and information available at this time do not indicate that Prozac causes suicidality or violent behavior," Meyer stated. CCHR, which is affiliated with the Church of Scientology, petitioned FDA in October 1990 to withdraw Lilly's Prozac (fluoxetine) from the market on the basis that the drug causes suicidal tendencies, violent acts, tardive dystonia and tardive dyskinesia, and is addictive. CCHR cited anecdotal and clinical evidence of suicides and attempted suicides by individuals on Prozac therapy. In addition, the group pointed to several murders that had been committed by individuals taking the drug. In its denial of the CCHR petition, the agency notes that "suicidal ideation" was added to the adverse reactions section of Prozac labeling after the agency received postmarketing reports of "emergence or intensification of suicidality during Prozac therapy." However, FDA argues that "there is no way to know whether to attribute the reported suicides and deaths to the underlying disease, intervening life events or drug therapy." FDA is planning to bring the issue of suicidality of all antidepressants before its Psychopharmacological Drugs Advisory Committee in September. The agency informed antidepressant drug manufacturers in a June letter that the committee would be meeting on the issue ("The Pink Sheet" July 22, T&G-9). "Any action that is warranted as a result of the recommendations of the advisory committee will be taken at that time," Meyer said. A date has not yet been set for the meeting. FDA said the growing number of reports of Prozac-associated suicide attempts "does not necessarily mean that the occurrence of the adverse experience has increased." The increased frequency may simply mean that "more of the events that occurred are reported," FDA explained. "External factors, such as increased publicity of the possibility that Prozac causes suicide, could be responsible for such an increased frequency of reporting," the agency remarked. The increase in adverse event reporting should be viewed "as a signal of the possibility of a phenomenon that should be studied by other means," FDA noted. FDA further maintained that data from the controlled clinical trials with Prozac do not support the anecdotal findings cited by CCHR. The results of a reanalysis of the data by Lilly on the 3,065 patients treated with Prozac, tricyclic antidepressants or placebo show that there was no statistically significant difference between suicidal behavior in any of the groups. Among the 1,765 patients treated with Prozac, there were six suicidal acts compared to two among the 731 tricyclic antidepressant- treated patients and one act for the 569 placebo-treated patients. Lilly also analyzed data on 3,000 patients who had their suicidal tendencies measured by the Hamilton Psychiatric Rating Scale for Depression (HAM-D) Item 3. FDA noted that "Prozac patients experienced a statistically significantly greater decrease in mean suicidality scores than placebo patients." In addition, fewer Prozac-treated patients experienced emergent suicidality over the treatment period than placebo-treated patients, 1.2% compared to 2.6%. FDA also concluded that there is no evidence that Prozac causes obsessive suicidality as asserted by CCHR. Reviewing CCHR's main reference, a study by Teicher et al., FDA said that other factors such as "unremitting depression, disease complexity, prior history of suicidality, concomitant medication, and possibly excessive doses of Prozac, may have contributed to the . . . suicidality" observed in six patients in the study. In response to CCHR's assertion that Prozac has caused violent behavior in some people to the point of committing murder, FDA said that none of the isolated events cited by the group "provides persuasive evidence that Prozac caused the violent behavior." The agency asserted that, in one of the cases cited by CCHR, a person, who killed eight people and himself, "had a history of multiple suicide attempts, including overdose, carbon monoxide poisoning, and attempted hanging." With regard to eight cases of murder currently pending against people who were being treated with Prozac at the time of the criminal act, FDA maintained that "it is obvious that arguments made by attorneys in attempts to absolve clients accused of murder do not constitute scientific evidence of the effects of a drug product." The agency noted, however, that "an actual court finding of a causal relationship between Prozac and violent behavior would be relevant" and could cause FDA to re-evaluate its position. No such court decision has ever been issued, FDA said.