CLEVELAND, April 20 /PRNewswire-FirstCall/ -- Cleveland BioLabs, Inc. (NASDAQ:CBLI)(BostonStockExchange:CFB), today announced the results of a study of the effects of Protectan CBLB612, the lead compound in the Protectans 600 series, on proliferation and mobilization to peripheral blood of pluripotent hematopoietic stem cells in a primate model (Rhesus macaques).

CBLB612 was found to be highly efficacious in stimulating proliferation and mobilization of hematopoietic stem cells into peripheral blood in these primates. A single injection of CBLB612 in Rhesus macaques resulted in a 20- fold increase of hematopoietic progenitor cells in blood. At the peak of the effect (48-72 hours post-injection) the proportion of free-floating CD34+ cells in the total white blood cell count reached 30% (compared with 1.5% in normal blood). CD34 is a molecule present on certain cells within the human body. Cells expressing CD34, otherwise known as CD34+ cells, are normally found in the umbilical cord and bone marrow as hematopoeitic cells.

Cleveland BioLabs President and Chief Executive Officer, Michael Fonstein, Ph.D., commented, "The results of this study are outstanding and further support the potential of Protectan CBLB612 as a convenient source of adult stem cells mobilized in peripheral blood. We believe that the effects of CBLB612 on stem cell proliferation and mobilization may be even further improved after we complete a series of dose/schedule optimization studies."

A common current therapeutic approach for increasing the amount of hematopoietic stem cells in blood is multiple injections of granulocyte-colony stimulating factor or G-CSF (Neupogen®, Granocyte®, Neulasta®). G-CSF is a human growth factor that works by inducing bone marrow to produce more white blood cells and early hematopoietic stem cells in particular. The effect of a single dose of CBLB612 on the proportion of hematopoietic progenitor cells in blood was comparable to that of four daily injections of G-CSF.

A report published by the National Institute of Health (NIH) division of the Department of Health and Human Services entitled "Regenerative Medicine 2006," notes that hematopoietic stem cells have been used clinically since 1959 and are used increasingly routinely for transplantations, albeit almost exclusively in a non-pure form. More than 40,000 transplants were performed annually worldwide by 1995. Currently, the main indications for bone marrow transplantation are either hematopoietic cancers (leukemias and lymphomas), or the use of high-dose chemotherapy for nonhematopoietic malignancies (cancers in other organs). Other indications include diseases that involve genetic or acquired bone marrow failure, such as aplastic anemia, thalassemia sickle cell anemia, and increasingly, autoimmune diseases.

Recent research efforts utilizing adult stem cells include a study in Brazil, which used stem cells made from patients' own blood to treat Type I diabetes. Preliminary results of the treatment, which were detailed in the April 11 Journal of the American Medical Association, showed that 13 of the 15 patients have so far been able to able to stop using insulin to treat their disease. Researchers at Imperial College in London have also used adult stem cells cultivated from bone marrow to grow a human heart valve.

Cleveland BioLabs's Protectans 600 series are modified factors of Mycoplasmas. Protectan CBLB612 has demonstrated both radiation protection and mitigation properties over a very broad time window of use. In animal experiments, Protectan CBLB612 has produced complete and sustained recovery of the hematopoietic (bone marrow/blood production) system following lethal doses of radiation.

About Cleveland BioLabs, Inc.

Cleveland BioLabs, Inc. is a drug discovery and development company leveraging its proprietary discoveries about programmed cell death to treat cancer and protect normal tissues from exposure to radiation and other stresses. The Company has strategic partnerships with the Cleveland Clinic Foundation, Roswell Park Cancer Institute, ChemBridge Corporation and the Armed Forces Research Radiobiology Institute. To learn more about Cleveland BioLabs Inc., please visit the company's website at http://www.cbiolabs.com.

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements reflect management's current expectations, as of the date of this press release, and involve certain risks and uncertainties. Our actual results could differ materially from those anticipated in these forward-looking statements as a result of various factors. Some of the factors that could cause future results to materially differ from the recent results or those projected in forward-looking statements include the "Risk Factors" described in our filings with the Securities and Exchange Commission.