Exopharm (ASX:EX1), which is developing medicines using exosomes from cells, has announced data from a preclinical study of its Cevaris product.
The in vitro BioMAP study was conducted to investigate the safety and function of Cevaris. The company said it was determined to be non-toxic at the tested concentrations. It said Cevaris also demonstrated immunomodulatory, tissue remodelling and inflammatory activities in addition to exhibiting proliferative effects in fibroblasts indicating potential utility in wound healing and related activities.
"Following on from the PLEXOVAL II clinical study and validation of the safety profile of products manufactured using the LEAP technology, an in vivo animal study investigating induced osteoarthritis in the knee and treatment with the Cevaris and Plexaris products was conducted at Cellvax, an independent French CRO," said the company.
"The investigative study demonstrated the products to be well-tolerated by the animals with no toxicity, no adverse effects or knee swelling observed through to termination. The study safety results were encouraging for future use of Cevaris and Plexaris," it said, adding, "The initial test model, where the chemically induced OA caused a severe condition, was however not optimal for testing tissue regeneration. The model produced defects which in the human clinical setting would warrant knee replacement rather than medicinal treatment. This result points to a potential study in a mild to moderate OA model more reflective of the targeted indication in humans."
“Initially, we were surprised to see no beneficial effect of either Plexaris or Cevaris over control until we looked at the knee scans. We realised that in this testing, the knee joints were damaged beyond repair, with no obvious cartilage cells available to respond to the exosome treatment. To accurately evaluate the exosome efficacy, we will need to have a model that has a less severe joint damage as the baseline to gather meaningful efficacy data,” said Dr Angus Tester, head of product evaluation.