Heart Damage: Another Cover-Up?

Rezulin was approved on the fast track in 1997, but links to at least 56 cases of heart failure and 90 cases of liver failure ended up sparking a debate over Congress’ demand for speedy reviews of new prescription drugs. Previously undisclosed documents and interviews showed that Rezulin heart defects were also a concern from the beginning. Rezulin was FDA approved in just six months, which did not allow a complete clinical trial to determine if Rezulin side effects caused heart damage. Instead, the Echo Study was put together to determine whether the use of Rezulin for 48 weeks would result in a change in the left ventricle. A left ventricle change would indicate heart failure because it can result if it cannot contract forcefully enough.

Dr. Paresh Dandona, the endocrinologist who served as Warner-Lambert’s principal investigator for the Echo study in Buffalo, said “The Echo Study was not properly conducted, according to the standard protocol. I was not made aware of the fact that the patients from this site, in particular, for whatever reason, whether it was due to technique or whatever, that they had increased left ventricular mass,” (L.A. Times, 3-26-00). Dadona also added that he had delegated a majority of the work to heart specialists that had deviated from the Echo Study procedures when studying up to one third of the Rezulin patients.

As far back as October 18, 1996, concern was raised over the safety of Rezulin in regards to its potential for adverse heart side effects. Dr. Robert I. Misbin, an FDA diabetes specialist, wrote an email to a former FDA medical officer who had studied Rezulin in the 1990’s and recommended its rejection, Dr. John L. Gueriguian, saying, “my primary concern about Rezulin is related to its potential for cardiac toxicity,” (L.A. Times, 3-26-00). Many diabetes patients, an estimated 15 million Americans, are overweight and have a far higher risk of developing congestive heart failure, which made the issue of the use of Rezulin and its potential side effects to cause heart problems especially important.

After the FDA approval of Rezulin on January 29, 1997, officials had negotiated a nonbonding pledge from Warner-Lambert to start a new study to assess Rezulin’s side effects on patients who had preexisting heart disease evidence. Few patients were enrolled, and this study was never completed. Rezulin patients did die of heart failure side effects, but doctors claimed many of these patients had preexisting heart problems. Guston Turner, a pharmacist from the FDA’s scientific investigations division had found inconsistencies in research measuring Rezulin’s side effects on the heart. Turner felt that the FDA “should have delayed approval of Rezulin until all the questions were addressed,” (L.A. Times, 3-26-00).

Serious, life-threatening Rezulin side effects have been directly linked to the use of the diabetes drug. Warner-Lambert has been blamed in dozens of deaths from life failure and thousands of other liver damage and side effects cases from 1997-2000.