Ranolazine has been previously shown to improve exercise capacity and symptoms in patients with severe chronic angina treated with standard doses of beta-blockers and calcium-channel blockers, without a significant effect on heart rate or blood pressure. The purpose of this study was to assess whether the benefit of ranolazine extends to the subgroup of angina patients treated with maximally-tolerated doses of beta-blockers or calcium blockers. In this post-hoc analysis, 258 patients from the Combination Assessment of Ranolazine In Stable Angina (CARISA) trial were considered as treated with maximally-tolerated doses of beta-blockers or calcium-channel blockers (systolic blood pressure (SBP) ≤ 100 mm Hg, and/or a resting heart rate ≤ 60 beats per minute, and/or an ECG PR interval ≥ 200 msec). Change from baseline in total exercise duration after 12 weeks compared to placebo were 34.5 (95% CI 0.8; 68.1) sec (p = 0.045) with ranolazine (750/1000 mg bid) at trough drug levels and 46.3 (13.5; 79.1) (p = 0.006) at peak drug levels. The number of angina attacks per week compared to baseline were reduced compared to placebo (-2.3 ± 0.3 vs -0.9 ± 0.6 (p < 0.001)). The effects of ranolazine 750 mg bid and 1000 mg bid were similar and the beneficial effects of ranolazine in this subgroup of maximally-treated patients were consistent with those not on maximally-tolerated doses of the background therapy. Ranolazine is effective for the symptomatic treatment of patients with stable angina on background therapy with maximally-tolerated doses of first line anti-anginal therapies.