Evaluating Treatment Preferences and the Efficacy of Capsaicin 179 mg Patch vs. Pregabalin in a Randomized Trial for Postsurgical Neuropathic Pain in Breast Cancer: CAPTRANE.

CAPTRANE evaluated the efficacy and tolerability of high-concentration capsaicin patch (HCCP) vs. oral pregabalin for the treatment of postsurgical neuropathic pain (PSNP) following breast cancer surgery. The study was designed with the aim of demonstrating noninferiority of one HCCP against daily pregabalin. This was a multicenter, randomized, parallel-arm, open-label study conducted across nine centers in France. The primary endpoint was a change from baseline in the Numeric Pain Rating Scale (NPRS) score after 2 months. Recruitment challenges resulted in the randomization of 140 patients (versus 644 planned); the per-protocol population comprised 107 patients (HCCP: n = 65; pregabalin: n = 42). Baseline characteristics were similar between the two groups. In the per-protocol analysis, the mean (standard deviation) change versus baseline in NPRS score was -1.926 (2.554) with HCCP and -1.634 (2.498) with pregabalin. The prespecified analysis showed that HCCP was not inferior to pregabalin: the lower bound of the 90% confidence interval for the between-arm difference was -0.889 and the upper bound was +0.260 (i.e., below the predefined clinical threshold of +0.4). Patient-reported outcomes showed no statistically significant differences between treatments. The painful area size decreased significantly more with HCCP. Tolerability profiles differed, with HCCP mostly causing application-site reactions. While >50% of patients switched from pregabalin to HCCP, none switched from HCCP to pregabalin. This comparative study in PSNP post breast cancer surgery, evaluating a single treatment of HCCP, shows a noninferior reduction in pain intensity, a superior reduction in painful area size, and a patient preference for HCCP compared with pregabalin. Despite limitations, it contributes valuable initial data for PSNP management in breast cancer care.