Mesoblast (ASX: MSB) Clinical Trial for Eye Diseases
Receives Singapore Health Sciences Authority (HSA) regulatory clearance to begin P2 trial of its proprietary allogeneic (off-the-shelf) adult stem cell therapy for patients with proliferation of leaky blood vessels in the eyes – neo-vascular (“wet”) Age-related Macular Degeneration (AMD).
ASX: MSB’s randomized, placebo-controlled P2 trial will recruit 18 patients at the Singapore National Eye Centre:
- The trial will evaluate the safety and effectiveness of a single intraocular injection of Mesoblast’s allogeneic Mesenchymal Precursor Cells (MPCs) combined with the anti-VEGF agent Lucentis in newly-diagnosed wet AMD patients;
- Controls will receive Lucentis alone;
- The trial will seek to establish if the allogeneic MPC treatment reduces the need for repeated monthly injections of Lucentis whilst improving visual acuity and quality of life.
Mesoblast’s proprietary adult stem cells may be effective for both forms of wet AMD since they have successfully reduced excessive blood vessel formation and leakiness in several preclinical studies:
- Results from a study at the Lions’ Eye Institute in Western Australia in 30 rodents with laser-induced excessive blood vessel formation showed that a single intra-ocular injection of human MPC prevented development of leaky blood vessels beyond day 7 after laser-induced damage (eyes treated with MPC had 39% and 32% non-leaky vessels at days 14 and 28, compared with only 7% and 2% non-leaky vessels in the controls at the same time-points, p<0.05). Moreover, at day 28 only 9% of vessels in eyes treated with a single MPC injection were severely leaking compared with 28% of vessels in control eyes (p<0.05);
- Results from a trial at Charles River in Canada in 42 non-human primates with laser-induced excessive blood vessel formation showed that combining a single injection of Mesoblast’s allogeneic cells with an injection of the anti-VEGF agent Lucentis resulted in a synergistic, and superior, outcome compared with Lucentis alone in reducing severity of blood vessel leakage within 2 weeks (p<0.05), preventing relapse of severe vessel leakage by days 28-42 (p<0.05), reducing total formation of new blood vessels (p<0.01), and preventing retinal detachment by day 42 (p<0.01).
The Bottom Line: Preclinical results to date suggest that a single injection of Mesoblast’s allogeneic cells may be effective for patients with wet AMD, either in combination with an anti-VEGF agent for the form seen in North America/Europe or in combination with photodynamic therapy for the PCV form seen in Asia. Initiating this P2 trial in Singapore will help lay the foundation to launch larger trials in parallel for wet AMD in both Asian and non-Asian populations. In Asia, wet AMD affects as many as 1.9% of people 65 or older. However, up to 55% of cases of wet AMD in Chinese, Japanese, and Malay populations are caused by Polypoid Choroidal Vasculopathy (PCV), a disorder of eye blood vessel proliferation that is different from the wet form seen in North America and Europe. Anti-VEGF therapy does not result in adequate regression of PCV lesions, and for this reason first line therapy for PCV is photodynamic therapy.