The objective of this prospective, multicenter study is to characterize responses to percutaneous medial branch peripheral nerve stimulation (PNS) to determine if results from earlier, smaller single-center studies and reports were generalizable when performed at a larger number and wider variety of centers in patients recalcitrant to non-surgical treatments. Participants with chronic axial low back pain were implanted with percutaneous PNS leads targeting the lumbar medial branch nerves for up to 60 days, after which the leads were removed. Participants were followed long-term for 12 months after the 2-month PNS treatment. Data collection is complete for visits through end of treatment with PNS (Primary Endpoint) and 6 months after lead removal (8 months after start of treatment), with some participant follow-up visits thereafter in progress. Clinically and statistically significant reductions in pain intensity, disability, and pain interference were reported by a majority of participants. Seventy-three percent of participants were successes for the Primary Endpoint, reporting clinically significant (≥30%) reductions in back pain intensity after the 2-month percutaneous PNS treatment (n=54/74). While prospective follow up is ongoing, among those who had already completed the long-term follow up visits (n=51), reductions in pain intensity, disability, and pain interference were sustained in a majority of participants through 14 months after the start of treatment. Given the minimally invasive, non-destructive nature of percutaneous PNS and the significant benefits experienced by participants who were recalcitrant to non-surgical treatments, percutaneous PNS may provide a promising first-line neurostimulation treatment option for patients with chronic axial back pain.