Mesoblast (ASX:MSB) has reached a key milestone in its bid to bring a non-opioid, disease-modifying treatment for chronic low back pain to market, announcing that the pivotal Phase 3 trial of rexlemestrocel L has hit its patient recruitment target.
The randomised, placebo-controlled study will follow at least 300 patients who receive a single intradiscal injection of the company’s second-generation stromal cell therapy combined with hyaluronic acid or a sham control, with a 12-month primary endpoint for pain reduction.
The trial is designed to confirm the clinically meaningful pain relief and opioid reduction seen in the earlier MSB-DR003 study and is powered to detect a significant difference in pain at 12 months. Secondary measures will track function, quality of life and cessation of pain medication, including opioids. Top-line results are expected in mid-calendar year 2027, after the last randomised patient completes follow-up, and Mesoblast anticipates using a positive readout to support a regulatory filing with the US Food and Drug Administration in the third quarter of calendar 2027.
Rexlemestrocel L has a Regenerative Medicine Advanced Therapy designation from the FDA, which provides eligibility for priority review once a Biologics License Application is filed. Mesoblast highlights the program’s particular focus on patients using opioids, noting that discogenic back pain accounts for roughly half of prescription opioid usage in the United States and that the earlier trial showed significant pain reduction and opioid cessation.
Chief Executive Silviu Itescu framed the achievement as a turning point for the company’s strategy, saying, “This is a major milestone toward delivering on our corporate goal of bringing to market a non opioid, disease-modifying therapy for patients suffering from chronic low back pain, a condition with significant unmet medical need.”
Chronic low back pain due to degenerative disc disease affects millions of Americans and is a leading cause of disability and diminished quality of life. Mesoblast positions rexlemestrocel L as a potential blockbuster opportunity, with estimated peak-year revenue exceeding US$10 billion at single-digit market penetration. The company also underscores its industrial-scale manufacturing, global intellectual property portfolio, and prior regulatory experience with its remestemcel L platform.