Rationale and design of the Study Assessing the Effect of Cardiovascular Medications Provided as Low-cost, Evidence-based Generic Samples (SAMPLES) trial

BackgroundHighly effective generic cardiovascular medications are frequently underused, leading to greater overall drug costs and cost-related nonadherence.ObjectiveWe sought to assess an intervention to stimulate appropriate generic cardiovascular drug use without creating administrative or financial barriers that may impede essential medication use.Trial designThe SAMPLES (Study Assessing the Effect of Cardiovascular Medications Provided as Low-cost, Evidence-based Generic 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 data on filled prescriptions obtained from a state-sponsored prescription drug assistance program to perform an intention-to-treat evaluation of the impact of the intervention on physician prescribing behavior (proportion of prescriptions that are generic) and patient adherence. Secondary outcomes will include physician adherence to established guidelines and overall prescription drug costs.ConclusionThis trial will define the potential role of an innovative approach to stimulate clinically appropriate cost-effective prescribing. We will determine whether free generic samples can reduce overall drug costs as well as out-of-pocket costs to the patient without sacrificing efficacy and whether this approach results in improved adherence to essential cardiovascular medications. This intervention may also improve adherence to practice guidelines and improve the quality of care received. If effective, this strategy could be used broadly by private insurers or government payers aiming to stimulate more cost-effective and higher-quality care.