Petition to the Food and Drug Administration to ban troglitazone/Rezulin due to its causing several cases of liver failure. (HRG Publication #1449) July 27, 1998
Michael Friedman, M.D.
Dear Dr. Friedman, We have obtained information from the FDA that as of June 5, 1998, there had been at least 21 deaths from liver failure and three patients requiring liver transplants caused by the recently-approved diabetes drug, troglitazone (Rezulin-Parke- Davis/Warner Lambert). In addition, there have been more than 100 patients hospitalized with liver toxicity caused by the drug. Since June 5th, there have been at least five additional deaths from liver damage associated with the use of this drug reported to the FDA for a total of at least 26 deaths from liver failure. The total number of reports received by the FDA in which liver toxicity was associated with troglitazone is more than 560 since March, 1997, when the drug was first marketed. Given that it is estimated that only about one in ten adverse reactions which occur are reported to the the FDA, it is likely that there may be as many as 200 deaths from liver damage which have actually occurred. Public Citizen's Health Research Group hereby petitions the FDA pursuant to 21 CFR, section 10.30 to initiate action to ban troglitazone as authorized by 21 U.S.C., section 355 (e) of the Federal Food, Drug and Cosmetic Act because earlier attempts to prevent its liver-damaging toxicity have failed. The inadequate response to this latest information about the deaths caused by troglitazone--another warning letter planned for this week from Parke-Davis to doctors and minor changes in the labeling agreed upon by the company and the FDA (see attached chronology)--are doomed to the same failure as the previous, similar warning efforts with the drug. In addition, Duract, a painkiller approved in 1996, was recently banned after four patients had died of liver damage and eight patients had required liver transplants. A boxed warning label, advising how to "safely" use the drug had been added in February, 1998, but was not effective and, after additional patients had died of liver damage, the drug was banned in June of this year. In December, 1997, based on 130 worldwide cases of liver damage linked to troglitazone, including six deaths, the British government concluded that "the risks of troglitazone therapy outweigh the potential benefits" and the drug was withdrawn from the UK. The British government added that "at present, no clear risk factors for the development of hepatic reactions have been identified which might allow the drug to be used safely in some patients." Glaxo-Wellcome, which had been marketing the drug in the UK, also withdrew license applications for troglitazone under the European Commission's "mutual recognition" process and all other regulatory activity for the drug on Glaxo's part has also been suspended. Instead of withdrawing the drug in the United States, the FDA, in December, 1997, increased the amount of monitoring of patients for liver damage (blood tests to detect this) to ten times in the first year of use from the previous five times which had been in effect for a month. Almost all of the deaths from liver toxicity have occurred after the latest (December 1, 1997) label change (which included a boxed warning) was made, reflecting the fact that the warnings are clearly inadequate to prevent the increasing amount of serious, often fatal liver damage occurring in patients using troglitazone. As of now, this drug is only available in the United States and Japan, all other countries and one of its developers, Glaxo-Wellcome, being too concerned to allow such a dangerous drug to be marketed. History of Knowledge of Liver Toxicity (see attached chronology) Before troglitazone was approved, 1.9% of patients in clinical trials getting the drug had abnormal liver tests (three or more times normal) compared with 0.6% of placebo-treated patients. Twenty patients treated with the drug (out of 2510) were withdrawn from treatment because of abnormal liver tests. During the December, 1996 FDA advisory committee meeting which recommended approving troglitazone, concern about the drug concentrating in the liver (30 times the concentration in plasma, in rats) was expressed by the FDA. It was stated that "at least in rats we have reason to be concerned about what might happen ultimately in liver, a target tissue." When the drug was first approved, however, there was no recommendation for monitoring of liver function, only a precaution with the above information about abnormal liver tests in people during the trials. Several months after the marketing launch of troglitazone in March, 1997, some cases of liver damage began to be reported and by October 28, 1997, there were 35 post-marketing reports of liver injury including 2 cases of liver failure, one resulting in a death, one in a transplant. The FDA-Parke-Davis response to this was to add a non-boxed warning to the label about "rare" cases of liver failure and to recommend that liver tests on patients using the drug be done five times during the first year of use. A "Dear Doctor" letter was sent on October 28, 1997. As mentioned above, by December, 1997 there had been 130 cases of liver toxicity including six deaths worldwide and the drug was withdrawn from the market in the U.K. A boxed warning was added to the label in the U.S. and the frequency of liver tests was increased to 10 times in the first year of use of the drug. Another "Dear Doctor" letter was sent by Parke-Davis to U.S. doctors on December 1, 1997. In June, 1998, because of a death in a patient in an NIH-sponsored study using troglitazone who had developed liver failure, the treatment arm of the study which involved the use of the drug was canceled. This study was examining the possibility that drugs such as troglitazone could prevent the development of diabetes. The patient who died was one of 585 patients getting troglitazone in the study. Now, in the face of at least 25 deaths from liver failure and 3 additional patients requiring liver transplant, the frequency of liver tests has been increased to 11 times during the first year of use. Additional changes in the label include repeating liver tests if results show 1.5 to 2 times elevation above normal and stopping the drug after two months, if it is being used as the sole treatment for diabetes and it has not been found effective by then. Another "Dear Doctor" letter is being sent. There is little question that the newest round of label changes will be as ineffective as the previous ones in stemming the rapidly-rising number of deaths from liver failure in patients using troglitazone. It is unfortunate that the recent case of Duract, in which warning labels similarly failed to prevent fatal cases of liver damage and the drug had to be banned to protect the American public, has not led to the ban of troglitazone in this country, a ban which has now been in effect for almost eight months in the United Kingdom. How many more Americans will have to die or require liver transplants before Parke-Davis and the FDA take action to protect people in this country by banning the drug? ENVIRONMENTAL IMPACT STATEMENT Nothing requested in this petition will have an impact on the environment. CERTIFICATION We certify that, to the best of our knowledge and belief, this petition includes all information and views on which this petition relies, and that it includes representative data and information known to the petitioners which are unfavorable to the petition. We look forward to a prompt response to this petition. Sincerely, Sidney M. Wolfe, M.D.
Larry Sasich, Pharm. D., M.P.H.
TROGLITAZONE (REZULIN) CHRONOLOGY
REFERENCES 1. Troglitazone (Rezulin) Professional Product Labeling. Physicians' Desk Reference 52 ed. 1998 Montvale NJ:Medical Economics Company, Inc. 2. Dear Healthcare Professional Letter. Important Drug Warning. William R. Sigmund II, M.D., Vice President, Medical and Scientific Affairs, Parke-Davis, October 28, 1997. 3. Department of Health and Human Services, Food and Drug Administration. FDA Talk Paper: Rezulin Labeling Changes, November 3, 1997. 4. Dear Healthcare Professional Letter. William R. Sigmund II, M.D., Vice President, Medical and Scientific Affairs, Parke-Davis, December 1, 1997. 5. Department of Health and Human Services, Food and Drug Administration. FDA Talk Paper: Patient Testing and Labeling Strengthened for Rezulin, December 1, 1997. 6. Committee on Safety of Medicines. Troglitazone (Romozin) withdrawn. Current Problems in Pharmacovigilance 1997;23:13-16. 7. Troglitazone suspended in U.K. after more adverse events. Scrip No. 2290, December 5, 1997, page 15. 8. National Institute of Diabetes and Digestive and Kidney Diseases News Brief: NIDDK Discontinues Troglitazone Arm of "Diabetes Prevention Program" Clinical Trial. June 4, 1998. |