Mesoblast Limited (NASDAQ:MESO) shares rose 9.5% on Monday after the biotechnology company completed patient treatment in a pivotal Phase 3 study evaluating rexlemestrocel-L for chronic low back pain linked to degenerative disc disease.
The company said 350 patients have now been treated in the MSB-DR004 randomised controlled Phase 3 trial. Participants were assigned to receive either a single intra-discal injection of rexlemestrocel-L or a sham injection.
Strong investigator demand expands trial enrolment
Mesoblast had originally planned to enrol 300 patients in the study, but increased the total to 350 following strong demand from trial investigators.
The primary endpoint is designed to confirm whether a single injection of rexlemestrocel-L can deliver durable pain reduction at 12 months, building on results observed in an earlier clinical trial.
Secondary measures will assess changes in patient function and quality of life, as well as whether treatment can reduce or eliminate the need for pain medication, including opioids.
Top-line results expected in mid-2027
Mesoblast expects to report top-line data from MSB-DR004 in mid-2027, once the final patient treated in the study has completed the required 12-month follow-up period.
Rexlemestrocel-L has received Regenerative Medicine Advanced Therapy designation from the U.S. Food and Drug Administration for chronic low back pain caused by degenerative disc disease.
The designation means the therapy will be eligible for priority review once Mesoblast submits a Biologics License Application.
Mesoblast targets large chronic back pain market
According to Mesoblast, chronic low back pain associated with inflammation and degenerative disc disease affects more than 7 million people in the United States.
The condition also accounts for approximately 50% of prescription opioid use in the country, highlighting the potential demand for treatments capable of providing sustained pain relief while reducing dependence on medication.
Completion of patient treatment represents an important clinical milestone for Mesoblast, shifting attention towards the 12-month follow-up period and the anticipated Phase 3 results in mid-2027.