Persica Pharmaceuticals' PP353 Shows Promising Results for Chronic Low Back Pain in Phase 1b Trial Published in The Lancet
Key Insights
Persica Pharmaceuticals (search) published positive Phase 1b trial data for PP353 in The Lancet's eClinicalMedicine, demonstrating clinically meaningful pain reduction in chronic low back pain (search) patients with Modic Type 1 changes (search).
The randomized, double-blind, sham-controlled trial of 40 participants showed PP353 achieved a 3.4-point reduction in pain scores versus 2.0 points for placebo (p=0.028), with over 60% of patients experiencing ≥50% pain reduction at 12 months.
PP353, an intradiscal linezolid injection targeting bacterial infection (search) as the root cause of pain, reduced opioid use from 25% at baseline to 11% at 12 months and was well-tolerated with no severe treatment-related adverse events.
Persica Pharmaceuticals (search) has achieved a significant milestone with the publication of positive Phase 1b clinical trial data for PP353, a novel intradiscal antibiotic therapy for chronic low back pain (search) (cLBP) with Modic Type 1 changes (search), in The Lancet's eClinicalMedicine. The results demonstrate that PP353 delivers clinically meaningful and durable reduction in pain and disability by targeting the underlying bacterial cause rather than just symptoms.
Addressing an Unmet Medical Need
Chronic low back pain (search) is a disabling and debilitating disease affecting millions of people worldwide who have limited effective treatment options. PP353 represents the first targeted therapy for cLBP with Modic Type 1 changes (search), a patient subgroup that comprises approximately 25% of those with moderate to severe cLBP. This translates to four million people in the US, Europe and Japan who can be readily identified through MRI scans.
Most patients with Modic Type 1 changes (search) are not helped by existing standards of care, and evidence suggests that bacterial infection (search) is the key contributor to pain in this subgroup. Current treatment options provide only limited short-term relief or involve invasive and non-reversible nerve ablation procedures that do not address the underlying pathology.
Clinical Trial Results
The randomized, double-blind, sham-controlled Phase 1b trial involved 40 participants across four countries who had been suffering from severe back pain for an average of five years. Patients experienced high levels of disability affecting daily function, mobility, and quality of life prior to treatment.
Following two intradiscal injections administered on day 1 and day 5, patients experienced clinically meaningful improvements in pain and disability within 1-3 months, with continued gains through 12 months. The primary endpoint revealed a 3.4-point reduction in pain scores for the PP353 group versus 2.0 points for placebo (p=0.028), representing a 30% between-group difference.
Secondary Outcomes and Safety Profile
PP353 participants experienced substantial reductions in disability scores, with 63% improvement on the Roland Morris Disability Questionnaire and 51% on the Oswestry Disability Index, both significantly superior to placebo. Over 60% of PP353 participants achieved clinically meaningful pain reductions of ≥50% at 12 months.
The treatment also demonstrated a notable impact on analgesic use, including a decrease in opioid use from 25% at baseline to 11% at 12 months. Significant improvements were observed in key daily activities such as standing up, walking, climbing stairs, and maintaining normal home and work routines.
The treatment was well-tolerated with no severe treatment-related adverse events reported during the study period.
Innovative Treatment Mechanism
PP353 is a suspension of linezolid powder in a thermosensitive vehicle that is liquid at room temperature but increases in viscosity when injected into the site of infection and warmed to body temperature. This unique formulation prevents the medication from leaking out of the degenerate disc into adjacent tissues during injection. The therapy also contains a radio-opaque dye that allows physicians to use image guidance to ensure proper positioning in the target disc.
Industry Perspective
Dr. Steve Ruston, CEO of Persica Pharmaceuticals (search) Ltd, commented: "Publication of our Phase 1b results in a prestigious journal is an important milestone for Persica and clear validation of our science and approach. Our goal is to develop a novel and impactful treatment for the millions of people living with chronic Low Back Pain (search) - a condition that causes debilitating pain, severely diminishes quality of life, and places a huge burden on healthcare systems and society. PP353 represents a genuinely innovative treatment modality that targets the underlying cause of disease, rather than just the symptoms. We are pleased that discussions with the FDA have provided a clear path to registrational studies and market approval."
Dr. Michael Rud Lassen, Principal Investigator at MRL Spine Clinic, Copenhagen, added: "These results are very encouraging. A therapy that identifies the painful spinal site using imaging, delivers a targeted antibacterial intervention, and produces durable clinical improvement could transform the management of chronic Low Back Pain (search) with Modic changes. PP353 could provide meaningful benefits for this patient population. We look forward to further development of PP353 in a phase 3 study with the hope of helping patients to less painful daily living."