HAIFA, Israel, Sept. 21, 2015 (GLOBE NEWSWIRE) — Pluristem Therapeutics Inc. (PSTI.TA) (PSTI.TA), a leading developer of placenta-based cell therapy products, announced today that Pluristem and the National Institute of Allergy and Infectious Diseases (NIAID), a part of the National Institutes of Health (NIH), completed a successful meeting with the U.S. Food and Drug Administration (FDA) regarding the development program for PLX-R18 cells in the treatment of Acute Radiation Syndrome (ARS). ARS is caused by exposure to dangerously high levels of radiation, such as those that could occur in a nuclear catastrophe. The FDA communicated that the data presented at the meeting allow for the design of large animal studies, which are the only studies required to prove efficacy for FDA approval under the Animal Rule; this is the regulatory pathway followed when human efficacy trials are not ethical or feasible. The FDA also offered to assist Pluristem with the design of these trials. The NIAID, which has supported and conducted two earlier studies of PLX-R18 in a mouse model of ARS, communicated its interest in supporting and completing trials in large animals as well, pending protocol review by the FDA.
The FDA advised Pluristem to conduct a pilot study in large animals to determine the optimal dose of PLX-R18 as a treatment for the hematologic component of ARS. Once the optimal dose schedule is determined, a pivotal trial in large animals could commence. If successful, this trial would provide sufficient efficacy data for an application to the FDA for approval of PLX-R18 as a treatment for ARS.
“This positive meeting with the FDA is a major step forward for our PLX-R18 program, and we expect to submit a protocol to the FDA for the dosing trial in large animals as soon as possible,” said Pluristem Chair and CEO Zami Aberman. “FDA approval of PLX-R18 for ARS could generate U.S. government interest in stockpiling it for use in the case of a nuclear disaster, since PLX cell products are ideally suited for rapid initiation of treatment of large populations. Our cells do not require tissue matching prior to administration and can be administered quickly via intramuscular injection.” Mr. Aberman added, “We value our close working relationship with the NIH/NIAID, and look forward to continuing to collaborate with them.”
Previous NIH/NIAID studies of PLX-R18 in ARS
The NIH has supported and completed two mouse studies of PLX-R18 as a potential treatment of the component of ARS that affects bone marrow function. ARS involves severe, potentially lethal damage to the bone marrow’s ability to produce blood cells and platelets, as well as to other systems and organs. Severe damage to bone marrow quickly makes victims vulnerable to life-threatening hemorrhage, infection and anemia. A recently concluded NIH/NIAID study showed that administration of PLX-R18 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, and described the cells’ mechanism of action. The NIH/NIAID’s first study of PLX-R18 showed a substantial, statistically significant improvement in 30-day survival and overall survival of irradiated rodents given PLX-R18 versus a control.
