Rosiglitazone prior authorization safety policy: a cohort study

Area of Science:

• Pharmacoeconomics
• Clinical Pharmacy
• Health Services Research

Background:

• Prior authorizations (PA) aim to ensure safe and cost-effective medication use.
• A revised rosiglitazone label warned against concurrent use with nitrates or insulin, presenting a PA opportunity.
• Potential for PA to cause patients to discontinue necessary drug therapy.

Purpose of the Study:

• Evaluate antidiabetic drug utilization post-implementation of an electronic PA for rosiglitazone.
• The PA denied claims if patients had recent insulin or nitrate supply.
• Assess the impact of this safety-focused PA on medication adherence and safety.

Main Methods:

• Quasi-experimental study design using pharmacy claims data.
• Compared 1.4 million commercially insured members with a rosiglitazone PA to 2 million without.
• Analyzed claims for rosiglitazone, insulin, nitrates, and other antidiabetic therapies up to 180 days post-claim.

Main Results:

• Significantly fewer patients used rosiglitazone with insulin/nitrates in the PA group (2.4%) vs. comparison group (60.4%) at 30 days.
• This significant difference persisted at 180 days (2.4% vs. 37.8%).
• No significant difference in patients without antidiabetic therapy between groups at 60-180 days; PA decreased monthly rosiglitazone claims by 5.1 per million members.

Conclusions:

• The implemented electronic PA significantly reduced concurrent rosiglitazone use with nitrates or insulin.
• This intervention aimed to mitigate cardiovascular event risks in type 2 diabetes patients.
• The PA was associated with improved medication safety without evidence of increased therapy abandonment.