Efficacy and Safety Evaluation of a Large Niacin Therapeutic Interchange Program

Abstract

BACKGROUND An extended-release niacin product (Niaspan, Abbott Laboratories) was identified as a product with a less costly therapeutic alternative; a therapeutic product interchange was implemented. OBJECTIVE To evaluate the efficacy and safety of a product therapeutic interchange from Niaspan to a controlled-release niacin product (Slo-Niacin, Upsher-Smith Laboratories) among patients at a large US Department of Veterans Affairs health care facility. METHODS Patients with active prescriptions for Niaspan underwent a therapeutic product interchange to Slo-Niacin; following conversion of the product, the medical record for each patient was reviewed and pre- and postconversion clinical information and conversion details were transcribed into a database for subsequent analysis and study. The primary efficacy end point was pre- and postconversion level of low-density lipoprotein cholesterol; secondary efficacy end points were levels of serum total cholesterol, high-density lipoprotein cholesterol, and triglycerides. Abnormal serum liver enzyme levels greater than 3 times the upper limits of normal was the primary safety end point; blood hemoglobin A1c was assessed as a secondary safety end point. RESULTS A total of 5321 patients' medical records were reviewed; for the efficacy evaluation, 539 patients were maintained on a daily dose of Slo-Niacin that was the same as the previous Niaspan dose. The dosage of any other concurrently prescribed dyslipidemia medication was unchanged. Analysis of these cases indicated that the conversion of Niaspan to Slo-Niacin was not associated with a difference in serum lipids over a mean (SD) of 503.9 (98.0) postconversion observation days with the exception of a decrease in mean serum triglyceride concentration of 19.8 mg/dL (p = 0.0003). Evaluation of all 5321 patients given Slo-Niacin for up to 724 days did not detect any safety differences between Slo-Niacin and Niaspan. Local facility cost avoidance exceeded $800,000 in the first postconversion year. CONCLUSIONS Data from a medication use evaluation of modified-release niacin products therapeutic interchange in a large US Department of Veterans Affairs health care facility show that the switch from Niaspan to Slo-Niacin had no negative effects on lipid-altering efficacy or safety but generated significant cost avoidance.