HAIFA, Israel, Feb. 18, 2015 (GLOBE NEWSWIRE) — Pluristem Therapeutics Inc. (PSTI.TA) (PSTI.TA), a leading developer of placenta-based cell therapy products, announced today the positive results of a recently completed trial conducted by the U.S. National Institutes of Health (NIH) to evaluate PLX-R18 cells to treat bone marrow damaged by exposure to high levels of radiation, such as can occur after a nuclear disaster. Injection of PLX-R18 cells into muscle, as compared to a placebo, resulted in a statistically significant improvement in the recovery of white blood cell, red blood cell, and platelet levels in animals exposed to high levels of radiation. The data also suggested that the treatment may potentially be able to shorten time to recovery. High levels of radiation can destroy the body’s ability to produce these three blood lineages, and rapidly regaining that capacity is a key factor in surviving the hematologic component of acute radiation syndrome (ARS), a condition caused by high-dose irradiation that can involve severe, sometimes lethal damage to the bone marrow as well as other physiologic systems and organs.
The objective of this latest trial was to investigate the mechanism of action behind the significant improvement in survival in irradiated mice treated with PLX-R18 that was demonstrated in the NIH’s first efficacy study. The results of the current study indicate that intramuscular administration exerts a systemic healing effect on bone marrow, lending further support to the concept that Pluristem’s cells work systemically via secretion of therapeutic proteins, although the cells themselves remain in the muscle into which they were initially injected. While additional animal trials are needed prior to U.S. Food and Drug Administration (FDA) approval of PLX-R18 for use in ARS, no human trials would be required because product development is conducted under the FDA’s Animal Rule.
“Our PLX-R18 cell product was developed and targeted to become a strong candidate for government procurement programs designed to protect the population in the case of exposure to dangerous levels of radiation. PLX-R18 cells are an off-the-shelf cell therapy product with a long shelf life. They do not require matching before use and can be administered through intramuscular injection. These features are important to facilitate rapid initiation of treatment on a large scale. The study results also support Pluristem’s unique approach of injecting cells intramuscularly to enable the cells to remain in the body long enough to respond to signals from damaged tissues and adapt their therapeutic secretion profiles accordingly,” stated Zami Aberman, Chairman and CEO of Pluristem.
“We have had a productive working relationship with the NIH’s National Institute of Allergy and Infectious Diseases (NIAID), which has independently conducted its studies with PLX-R18 cells provided by Pluristem,” Aberman added.
Pluristem is developing PLX-R18 cells for other potential indications including enhancement of engraftment of transplanted hematopoietic stem cells for the treatment of bone marrow deficiency. Trials for this indication are ongoing at Case Western University and Hadassah Medical Center. Data from the NIH studies in ARS are expected to benefit Pluristem’s development of its hematology program.
