ABSTRACT: Postoperative adhesions constitute a substantial clinical problem in hand surgery. Fexor tendon injury and repair result in adhesion formation around the tendon, which restricts the gliding function of the tendon, leading to decreased digit mobility and impaired hand recovery. This study evaluated the efficacy and safety of the peptide PXL01 in preventing adhesions, and correspondingly improving hand function, in flexor tendon repair surgery.This prospective, randomised, double-blind trial included 138 patients admitted for flexor tendon repair surgery. PXL01 in carrier sodium hyaluronate or placebo was administered around the repaired tendon. Efficacy was assessed by total active motion of the injured finger, tip-to-crease distance, sensory function, tenolysis rate and grip strength, and safety parameters were followed, for 12 months post-surgery.The most pronounced difference between the treatment groups was observed at 6 months post-surgery. At this timepoint, the total active motion of the distal finger joint was improved in the PXL01 group (60 vs. 41 degrees for PXL01 vs. placebo group, p?=?0.016 in PPAS). The proportion of patients with excellent/good digit mobility was higher in the PXL01 group (61% vs. 38%, p?=?0.0499 in PPAS). Consistently, the PXL01 group presented improved tip-to-crease distance (5.0 vs. 15.5 mm for PXL01 vs. placebo group, p?=?0.048 in PPAS). Sensory evaluation showed that more patients in the PXL01 group felt the thinnest monofilaments (FAS: 74% vs. 35%, p?=?0.021; PPAS: 76% vs. 35%, p?=?0.016). At 12 months post-surgery, more patients in the placebo group were considered to benefit from tenolysis (30% vs. 12%, p?=?0.086 in PPAS). The treatment was safe, well tolerated, and did not increase the rate of tendon rupture.Treatment with PXL01 in sodium hyaluronate improves hand recovery after flexor tendon repair surgery. Further clinical trials are warranted to determine the most efficient dose and health economic benefits.ClinicalTrials.gov NCT01022242; EU Clinical Trials 2009-012703-25.