Effects of Xuefu Zhuyu oral liquid as adjunctive treatment for stable angina: a randomized controlled trial

BACKGROUND: Stable angina (SA) remains a major cause of global disability. Xuefu Zhuyu oral liquid (XZOL), a traditional Chinese medicine, is used for SA in China, but rigorous evidence of its efficacy is lacking. We aimed to evaluate the efficacy and safety of XZOL as an adjunctive therapy for patients with SA. METHODS: We conducted a multicenter, randomized, double‐blind, placebo‐controlled trial across six hospitals in China. Between June 2020 and June 2022, eligible patients with SA were randomly assigned (1:1) to receive either XZOL or a matching placebo for 12 weeks, in addition to standard antianginal therapy. All participants were followed for an additional 12 weeks. The primary outcome was the change in average angina pain intensity from baseline to week 12, measured on a 10‐cm visual analog scale (VAS). RESULTS: Of 263 patients screened, 148 were included in the full analysis set (74 per group). At week 12, patients receiving XZOL showed a reduction in VAS pain scores compared to placebo (adjusted mean difference, ‐0.63; 95% CI, ‐1.12 to ‐0.14; P = 0.012). This effect was sustained at the 24‐week follow‐up (‐0.47; 95% CI, ‐0.94 to ‐0.002; P = 0.049). Furthermore, the XZOL group had significantly lower use of rescue nitroglycerin at both week 12 (2.7% vs. 13.5%; P = 0.016) and week 24 (2.7% vs. 12.2%; P = 0.029). Adverse events were comparable between groups. CONCLUSION: Adjunctive treatment with XZOL for 12 weeks significantly reduced angina pain intensity and the need for rescue medication in patients with stable angina, with a favorable safety profile. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/, ChiCTR1900026899.