Collagenase Clostridium Histolyticum (CCH) in Patients with Plantar Fibromatosis (PFI): Post Hoc Analysis of a Phase 2, Double-Blind, Randomized, Placebo-Controlled Study

Research Type: Level 1 - Randomized controlled trial (RCT), Meta-analysis of randomized trials with homogeneous results Introduction/Purpose: CCH, a nonsurgical treatment approved in the US for treatment of adults with Dupuytren’s contracture with a palpable cord and adult men with Peyronie’s disease with a palpable plaque and curvature deformity of ≥30°, is being investigated for plantar fibromatosis (PFI), which is characterized by collagen-containing nodules along the medial/central plantar fascia. We describe post hoc analysis results in a subgroup of patients with PFI from a phase 2, randomized, placebo-controlled trial of CCH (Study 222; NCT05152173). Methods: Subgroup efficacy analyses were performed for Study 222 patients with ≥1 injection of CCH or placebo and ≥1 postinjection Foot Function Index (FFI) Pain subscale assessment. Patients with baseline Numeric Rating Scale pain score of 10 (ie, patients with extreme distress or pain) or nodule consistency (firmness) of “moderately firm” (nodules with less collagen content) were excluded. Endpoints included change from baseline to Day 57 in FFI Pain subscale, combined FFI Pain+Difficulty subscales, Clinician Global Impression of Change (CGIC), nodule hardness (durometer), and nodule consistency (firmness by palpation). Results were assessed using analysis of covariance, mixed model for repeated measures, or Cochran-Mantel-Haenszel test, as appropriate. Results: The subgroup analysis included 126 patients (CCH, n=61; placebo, n=65). Subgroup patients treated with CCH had significant improvements compared to placebo in FFI Pain (P=0.014) and Pain+Difficulty (P=0.020) subscales, CGIC score (P=0.025), nodule hardness (P=0.002), and nodule consistency (P < 0.001). CCH was well tolerated; no serious adverse events were reported. Conclusion: This subgroup analysis identified patients with PFI with a robust CCH treatment effect. An appropriately powered phase 3 trial (NCT06151197) is in progress.