Efficacy and Safety of Dorocontin^® versus Sustac^® in the Treatment of Stable Angina Pectoris: A Randomized, Double-Blind Comparative Trial

Background: Development of generic drugs has numerous benefits in terms of cost-efficiency and availability. Slow-release nitroglycerin is a vasodilator drug commonly prescribed for patients with angina pectoris. Objective: The objective of this study was to compare the efficacy and safety of generic slow-release nitroglycerin (Dorocontin^®) with that of the innovator brand (Sustac^®) in patients with stable angina pectoris. Methods: In this randomized, double-blind comparative trial, 110 patients were allocated to Dorocontin^® (n=67) or Sustac^® (n=43) at a dose of 6.4 mg TID, for a total period of two months. Maximum endurable MET (metabolic equivalent of task), MPI (myocardial perfusion imaging), along with changes in the ECG and biomarkers of renal (serum creatinine, BUN) and hepatic (AST, ALT, and ALP) function, lipid profile (total cholesterol, LDL-C, HDL-C, VLDL-C, and triglycerides), electrolytes (Na⁺ and K⁺), CBC-diff (RBC, WBC, Plt, Hb, Hct, MCV, MCH, MCHC, and RDW), and FBS were assessed at the baseline and at the end of the trial. The frequency of adverse events during the course of the trial was also recorded. Results: Apart from a significantly greater reduction in maximum ST depression in the Sustac^® versus the Dorocontin^® group (p=0.03), none of the functional (MET, MPI, and ECG) and paraclinical (renal function, hepatic function, lipid profile, electrolytes, and FBS) parameters significantly differed between the study groups. The mean Hb (p=0.035), Hct (p=0.045), and MCH (p=0.032) were decreased by the end of the trial in the Sustac^®, but not in the Dorocontin^® group, whilst there was no change in other CBC-diff parameters. Reported adverse events were not serious and included headache, vertigo, gastrointestinal upset, and orthostatic hypotension. The frequency of these adverse events was comparable between the study groups. Conclusion: The findings of the present trial showed comparable efficacy and safety of the generic and innovator products of slow-release nitroglycerin in the management of stable angina pectoris.