P-15 Peptide Enhanced Bone Graft Improves Time to Fusion in Transforaminal Lumbar Interbody Fusion

Study Design. – Prospective, multicenter, single-blind, randomized, controlled pivotal study. Objective. – Compare time-to-fusion in patients treated with P-15L (PearlMatrix^TM P-15 Peptide Enhanced Bone Graft) versus local autograft over 24 months and evaluate changes in pain and quality of life at 24 months relative to baseline. Summary of Background Data. – P-15L, an FDA-designated Breakthrough Device, is a composite bone graft with P-15, a 15-amino acid polypeptide that promotes cellular adhesion, proliferation, and differentiation to support bone formation. Methods. – Patients (22-80 y) with degenerative disc disease were randomized to the investigational (P-15L) or control (local autograft) group during single-level transforaminal lumbar interbody fusion (TLIF) with a PEEK cage and supplemental pedicle screw fixation. Fusion assessments occurred at 6, 12, and 24 months. Time-to-fusion was tested for superiority as compared to the control using Kaplan-Meier survival analysis. Back and leg pain were measured using the Visual Analog Scale (VAS) and quality of life was assessed using the Short Form Survey (SF-12). Results. – The analysis included 290 patients from 33 sites; 141 (48.6%) received P-15L and 149 (51.3%) received local autograft. At randomization, at least 1 risk factor for pseudoarthrosis (obesity, nicotine use, or diabetes) was reported in 58.9% (83/141) of the investigational group and 60.4% (90/149) of the control group. More patients in the investigational than the control group achieved fusion at 6 months (Kaplan-Meier fusion rates 57.6% vs 26.9%, respectively), 12 months (68.8% vs 41.5%, respectively), and 24 months (81.1% vs 54.9%, respectively). P-15L was statistically superior to autograft for time-to-fusion (hazard ratio=1.87, 95% CI: 1.47, 2.38; P<0.0001). There was marked improvement in VAS and SF-12 relative to baseline in both groups at 24 months. Conclusion. – P-15L promotes statistically superior earlier time-to-fusion than local autograft in instrumented TLIF. Both treatments resulted in clinically meaningful improvements in pain and quality of life at 24 months. Level of Evidence.