Endo International plc announced initial results from a Phase I study (EN3835–105) evaluating collagenase clostridium histolyticum (CCH) for the treatment of plantar fibromatosis. The data are being presented as an e-poster at the American Podiatric Medical Association Annual Scientific Meeting, The National, in Denver, July 29–August 1. Plantar fibromatosis (sometimes referred to as Ledderhose disease) is a rare condition in which an uncontrolled proliferation of fibrous tissue causes the formation of nodules on the bottom of the foot along the plantar fascia. If left untreated, the nodules can cause pain, discomfort, swelling and difficulty walking. CCH is composed of two purified collagenases that work to break down collagen when injected into fibrous tissue. The Phase I, open-label, randomized, dose-ranging study (EN3835–105) presented at APMA is the first trial to explore CCH for the treatment of plantar fibromatosis. EN3835–105 was an open-label, randomized, dose-ranging study that enrolled 24 patients ages 18 years or older with plantar fibromatosis. Participants with a palpable/ultrasound-measurable nodule in one or both feet were randomly assigned to one of the three dosing groups administered on Day 1: CCH 0.6 mg/mL, 1.2 mg/mL, or 2.25 mg/mL (0.12, 0.24, or 0.45 mg per injection, respectively). Nodules measuring =1.5 cm in diameter (by ultrasound) were treated with one intralesional injection and nodules >1.5 cm in diameter were treated with two injections. In total, 31 nodules were treated across all three dosing groups. For the primary outcome, treatment was generally well tolerated across all dosing groups, with no discontinuations due to treatment-related adverse events (AEs) and no serious treatment-related AEs reported. All treatment-related AEs were mild or moderate in intensity, with the most common being injection-site bruising, pain and swelling. Most (70.9%) of these AEs resolved within 21 days. For the secondary endpoints, more than 72% of patients across the three treatment groups indicated being "very satisfied" or "quite satisfied" with the first treatment of their nodule(s) at day 57. In addition, most investigators (>72%) reported improvements in the nodules across the treatment groups. The study also assessed foot function using a modified version of the Foot Function Index-Short Form-23 (FFI-SF-23),3 which measures foot pain, disability and difficulty performing activities. Nodule characteristics also were assessed by investigators using palpation to determine consistency (e.g., hard, firm, soft). At day 57, all treatment groups demonstrated improvements in modified FFI-SF-23 composite score and nodule consistency. Participants who received CCH 2.25 mg/mL had the highest percentage improvement from baseline in FFI-SF-23 composite score (78.8% compared with 41%, 0.6 mg/mL and 44.8%, 1.2 mg/mL). Improvement in softening of nodule consistency (=1 level) from baseline also were higher in the CCH 2.25 mg/mL group as well as the 1.2 mg/mL group (90% each, compared with 72.2%, 0.6 mg/mL). Collagenase clostridium histolyticum (CCH) is composed of 2 purified collagenases (AUX-I and AUX-II) that hydrolyze collagen under physiologic conditions, resulting in disruption of collagen containing structures. CCH (XIAFLEX) is currently approved by FDA for the treatment of adults with Dupuytren's contracture with a palpable cord and the treatment of adult men with Peyronie's disease with a palpable plaque and curvature deformity of =30 degrees at the start of therapy.