Mesoblast Limited (ASX:MSB, Nasdaq:MESO) today announced that Mesoblast's proprietary allogeneic mesenchymal precursor cell (MPC) heart failure product candidate MPC-150-IM for use in children with hypoplastic left heart syndrome (HLHS) was featured at the First Cardiac Regenerative Symposium for Congenital Heart Disease in Baltimore, Maryland on the weekend. The symposium focused on the potential for using cellular therapies in the treatment of complex congenital heart conditions.
A randomized, placebo-controlled 24-patient trial is ongoing at Boston Children's Hospital and combines an injection of MPC-150-IM into the left ventricle with corrective heart surgery in children under the age of five with HLHS. To date there have not been any cell-related safety concerns in the trial. Consequently, this trial has the potential to extend the safety profile of MPC-150-IM beyond adults, where it is being studied in two complementary late-stage clinical trials in patients with advanced and end-stage chronic heart failure, to children with congenital heart disease.
Dr Sitaram Emani, Associate Professor of Surgery at Harvard Medical School and Director of the Complex Biventricular Repair Program at Boston Children's Hospital, and the trial's Principal Investigator, said: "We believe that a direct injection of Mesoblast's cellular medicine into the hypoplastic left ventricle as an adjunct to surgical rehabilitation has the potential to promote growth and regeneration of that ventricle and recruit it back into the circulation. This provides a chance for the patient with this congenital disease to regain normal two-ventricle circulation commensurate with improved quality of life and longevity."
The underlying mechanism of action by which MPC-150-IM is thought to exert its therapeutic effects in both pediatric and adult patient populations, based on preclinical evidence, is through reduction of damaging inflammation, maturation of the vasculature, reduction in fibrosis, and cardiac repair.
A Phase 2b trial comparing an injection of MPC-150-IM or placebo into the left ventricle in 159 adult patients with end-stage heart failure receiving a left ventricular assist device (LVAD) implant completed enrollment in September 2017, with all patients having a planned follow-up of at least one year. The United States Food and Drug Administration (FDA) has granted Mesoblast a Regenerative Medicine Advanced Therapy (RMAT) designation for use of MPC-150-IM in these patients based on prior Phase 2 trial results showing improved heart function, prolonged time to re-hospitalization and improved early survival after a single intra-myocardial injection of Mesoblast's MPCs at the time of an LVAD implant. Full results of this Phase 2b trial will be presented by the trial's independent investigators at an upcoming conference.
A Phase 3 trial in approximately 600 patients with New York Heart Association (NYHA) Class II/III chronic heart failure is also being actively conducted in the United States, with over 85% of patients enrolled. The objectives of this Phase 3 events-driven trial are to evaluate the ability of a single catheter-based injection of MPC-150-IM to reduce heart failure-related major adverse cardiac events (HF-MACE) in patients with left ventricular dysfunction, as well as delay or prevent disease progression to end-stage heart failure and terminal cardiac events. In a prior Phase 2 trial, HF-MACE events were significantly reduced by a single intra-myocardial injection of MPC-150-IM. This trial has previously been successful in a futility analysis of the primary endpoint.