Racial differences on treatment response to triple single-pill combinations for hypertension: a secondary analysis of the OPTION TREAT Trial

Background Racial differences in treatment response to antihypertensive combination therapies remain uncertain. Purpose To assess whether race modifies treatment effects on systolic blood pressure reduction at 12 weeks. Methods The OPTION TREAT trial was a randomized, double-blind, multicenter study conducted in Brazil, comparing a novel triple single-pill (candesartan cilexetil 16 mg, amlodipine 5 mg, and chlorthalidone 12.5 mg) with an active control (valsartan 160 mg, hydrochlorothiazide 12.5 mg, and amlodipine 5 mg) in patients with uncontrolled hypertension. This secondary analysis evaluated changes in systolic blood pressure (SBP) from baseline to week 12 across self-reported racial groups (white, black, mixed-race) using mixed-effects models with random site effects, fixed effects for treatment and race, a race-by-treatment interaction term, and baseline SBP as a covariate. Results Among 673 participants with available data on race, 250 (37.1%) were white, 123 (18.3%) black, and 300 (44.6%) mixed-race. Mean age 57.9 ± 10.7 years; 62.4% were women. Baseline SBP was similar across racial groups (154.4 ± 10.6 mmHg in white, 151.6 ± 10.8 mmHg in black and 152.0 ± 10.5 mmHg in mixed-race). In the experimental arm, mean changes in SBP were −24.1 ± 16.6 mmHg in white, −26.4 ± 16.7 mmHg in black, and −23.2 ± 14.4 mmHg in mixed-race participants. In the active control arm, changes in SBP were −20.7 ± 15.5 mmHg, −17.2 ± 18 mmHg, and −20.0 ± 14.3 mmHg, respectively. Overall changes in SBP were −22.2 ± 16.1 mmHg in white, −21.8 ± 17.9 mmHg in black, and −21.7 ± 14.4 mmHg in mixed-race participants, with no statistically significant differences between race groups. Within each racial strata, the changes in SBP were −9.62 mmHg in black participants (95% CI −14.8 to −4.4), −3.52 mmHg in mixed-race participants (95% CI −6.9 to −0.2), and −3.31 mmHg in white participants (95% CI −7.0 to 0.3), with no significant interaction. Conclusion Race does not seem to influence treatment response to single triple-pill combination therapies. The comparative treatment effect of the novel triple single-pill versus active control was consistent across racial groups, with no evidence of effect modification. These findings support the broad applicability of triple single-pill regimens across diverse racial populations.