P-15 Peptide Bone Graft Outperforms Autograft for Spinal Fusion in Landmark RCT | Research

The takeaway

P-15L peptide-enhanced bone graft was superior to autograft for spinal fusion, achieving 84.3% vs 58.5% fusion rate and 55.5% vs 37.5% composite clinical success at 24 months in a 290-patient RCT.

84% vs 59% fusion
A 15-amino acid peptide bone graft outperformed the gold standard (patient's own bone) by 26 percentage points for spinal fusion

What the researchers found

P-15L was superior to autograft: fusion 84.3% vs 58.5%, composite clinical success 55.5% vs 37.5% (p=0.002 superiority), with similar device-related SAE rates at 24 months.

Why it matters

Autograft harvesting causes pain and complications. A peptide-based graft that works better eliminates this morbidity while improving outcomes.

How the study worked

Prospective, multicenter, single-blind, randomized, controlled pivotal study with 290 patients at 33 sites undergoing single-level TLIF, comparing P-15L to local autograft.

What this study cannot tell us

Single-level TLIF only. 24-month follow-up. Single-blind (surgeon knew allocation). Specific to lumbar spine.

How to read the evidence

Level I evidence: prospective multicenter RCT demonstrating superiority. Pivotal trial for FDA regulatory pathway.

When this study was published

Published in 2025.

The bigger picture

P-15 is one of the most clinically advanced therapeutic peptides, demonstrating that a single 15-amino acid peptide can outperform the body's own bone for surgical healing.

Questions still open

Would P-15L show similar superiority in cervical spine fusion?
Can P-15L replace all autograft indications in orthopedics?
What is the long-term fusion durability beyond 24 months?

Common questions

What is P-15L?

P-15L (PearlMatrix) is a bone graft material containing a small 15-amino acid peptide that promotes bone cell attachment and growth. It is placed during spinal surgery to help vertebrae fuse together.

Is it better than using my own bone?

Yes. In this trial, P-15L achieved 84% fusion vs only 59% with autograft (your own bone), and patients had better overall clinical outcomes while avoiding the pain of bone harvesting.

Read the original research

P-15 Peptide Enhanced Bone Graft in Transforaminal Lumbar Interbody Fusion: A Randomized, Controlled, Investigational Device Exemption Study Demonstrating Improved Composite Clinical Success.

Spine, 51(4), 238-247

View on PubMed ↗Publisher’s paper ↗

Citation

Harrop, James S; O'Toole, John E; Steinmetz, Michael P; Sasso, Rick C; Chaput, Christopher D; Strenge, K Brandon; Maislin, Greg; Mullin, Jeffrey P; Freeman, Thomas B; Guanciale, Anthony; Lantner, Howard; Janssen, Michael E; Schwartz, David G; Small, John M; Hsu, Wellington K; Arnold, Paul M. (2026). P-15 Peptide Enhanced Bone Graft in Transforaminal Lumbar Interbody Fusion: A Randomized, Controlled, Investigational Device Exemption Study Demonstrating Improved Composite Clinical Success.. Spine, 51(4), 238-247. https://doi.org/10.1097/BRS.0000000000005579