Impact of regulatory labeling for troglitazone and rosiglitazone on hepatic enzyme monitoring compliance: findings from the state of Ohio medicaid program.
OBJECTIVE
Troglitazone, the first drug of the thiazolidinediones class for type II diabetes, was first marketed in March 1997 and was removed from the U.S. market 36 months later after 90 cases of liver failure were reported despite multiple warnings containing liver enzyme monitoring recommendations. Rosiglitazone has been available since June 1999 and is still on the market. The purpose of this study was to evaluate the impact of labeled hepatic enzyme monitoring for troglitazone and rosiglitazone.


METHODS
Drug cohorts were assembled, using population-based fee-for-service Medicaid claims, for patients between 18 and 65 years of age who had received at least one troglitazone (n = 7226) or rosiglitazone (n = 1480) prescription between 1 April, 1997, and 21 March, 2000. The outcome of interest was the percentage of patients, based on their first treatment episode, who had baseline and post-baseline liver enzyme testing.


RESULTS
Overall baseline testing was under 9% before regulatory actions, increased to 14% after the first two 'Dear Doctor' letters issued by the FDA in October and December 1997, and peaked to about 26% afterwards. Coincident with the marketing of rosiglitazone and the fourth 'Dear Doctor' letter issued in June 1999, baseline testing dropped to 18%. Baseline testing increased 2.5-fold (race-sex-age adjusted) after regulatory action. Achieving 50% post-baseline testing took approximately 6 months for both drugs.


CONCLUSIONS
Regulatory actions had only modest effects on the incidence of liver monitoring. More effective and timely communication strategies, health provider prescribing interventions and modification of health provider behaviors to enhance compliance with recommended risk management measures need to be identified, evaluated and implemented.
Cluxton
Robert J
RJ
College of Pharmacy, University of Cincinnati, Cincinnati, OH 45267-0004, USA.
Li
Zili
Z
Heaton
Pamela C
PC
Weiss
Sheila R
SR
Zuckerman
Ilene H
IH
Moomaw
Charles J
CJ
Hsu
Van Doren
VD
Rodriguez
Evelyn M
EM
D002839:Chromans / Q000009:adverse effects / Q000627:therapeutic use*; D015331:Cohort Studies; D016208:Databases, Factual / Q000706:statistics & numerical data; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy; D004348:Drug Labeling / Q000331:legislation & jurisprudence* / Q000592:standards; D017723:Drug Utilization Review / Q000379:methods / Q000706:statistics & numerical data / Q000639:trends; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008099:Liver / Q000187:drug effects / Q000201:enzymology* / Q000503:physiopathology; D008111:Liver Function Tests / Q000379:methods / Q000706:statistics & numerical data; D008297:Male; D008484:Medicaid / Q000706:statistics & numerical data; D008875:Middle Aged; D009820:Ohio / Q000453:epidemiology; D017891:Pharmacoepidemiology / Q000379:methods; D010818:Practice Patterns, Physicians'; D000077154:Rosiglitazone; D045162:Thiazolidinediones / Q000009:adverse effects / Q000627:therapeutic use*; D000077288:Troglitazone; D014481:United States; D014486:United States Food and Drug Administration
D002839:Chromans; D045162:Thiazolidinediones; D000077154:Rosiglitazone; D000077288:Troglitazone