A Study Assessing the Effect of Cardiovascular Medications Provided as Low-cost, Evidence-based Generic Samples

Highly-effective generic cardiovascular medications are frequently underused, leading to greater overall drug costs and cost-related non-adherence. Interventions are needed to stimulate appropriate generic drug use without creating administrative or financial barriers to branded medications that may impede essential medication use.

The SAMPLES trial is a clustered, randomized controlled trial of the effect of providing physicians with free generic samples of hydrochlorothiazide for hypertensive patients and simvastatin for patients with hyperlipidemia. We will randomize 660 primary care physicians in Pennsylvania, clustered by physician practice, to receive free samples for both conditions or to receive no samples. We will use pharmacy claims of their patient population enrolled in a state-sponsored prescription drug assistance program to evaluate outcomes of interest. The primary outcomes are physician prescribing behavior (proportion of prescriptions that are generic), and patient adherence to chronic therapy. Secondary outcomes will include physician adherence to established guidelines (for anti-hypertensive regimens) and overall prescription drug costs. Primary analyses will be based on intention-to-treat principles.

This trial highlights a new and innovative approach to stimulate cost-effective prescribing. Free generic samples can reduce overall drug costs as well as out-of-pocket costs to the patient without sacrificing efficacy, and may result in improved adherence to essential cardiovascular medications. This intervention may also improve adherence to practice guidelines and improve the quality of care received. If found to be effective, this strategy could be utilized broadly by private insurers or government payers aiming to stimulate more cost-effective and higher-quality care.