Pluristem, Hadassah to Work on Stem Cell Cure for Radiation Damage

The startup has discovered that the injection of stem cells causes a marked improvement in the repopulation of bone marrow cells.

Pluristem Therapeutics, which develops stem cell-based therapies, signed a collaborative agreement for research with Hadassah University Hospital at Ein Karem last week. The agreement calls for continuing Pluristem's previously conducted pre-clinical animal studies to test treatment of radiation sickness using placenta cells. The earlier research indicated the therapy's significant potential for treating the effects of radiation exposure.

In its previous research the startup discovered that the injection of stem cells caused a marked improvement in the repopulation of bone marrow cells. The company subjected mice with weakened immune systems to high levels of radiation and then injected them with placental stem cells. After about five weeks significant recovery was noted in their blood cells and immune systems. It also found that the stem cells secrete proteins that protect cells damaged by radiation and prevent their death.

Prof. Raphael Gorodetsky, head of the radiobiology and biotechnology laboratory at Hadassah's Sharett Institute of Oncology, said that exposure to high levels of radiation could be fatal, but that today there is no efficient treatment except bone marrow transplants in the most severe cases, a complicated process that isn't always successful. The initial results of Pluristem's research are encouraging, he said.

In January, Pluristem received go-aheads from the U.S. Food and Drug Administration and the European Medicines Agency to skip second phase clinical testing of its flagship PLX-PAD treatment for limb ischemia from peripheral artery disease and continue straight to the decisive third phase trials.

Pluristem's method, as distinguished from other companies developing stem cell treatments, is to inject patients with doses twice, four months apart, without genetic matching and without subduing the patient's immune system.

The company, managed by Zami Aberman, raised $38 million at the end of January by issuing 11 million shares, 13% of the company's stock.