Cleveland BioLabs, Inc. (NASDAQ: CBLI) today announced results of a primate study demonstrating the efficacy of Protectan CBLB502 as a mitigator of hematopoietic (bone marrow/blood production) damage up to 48 hours post-radiation exposure.

Dr. Michael Fonstein, Chief Executive Officer and President of Cleveland BioLabs, commented, "Protectan CBLB502's strong mitigation of both gastrointestinal and hematopoietic radiation-induced damage have been well documented, warranting its potential use for military personnel and first responders. This is the first primate study pointing towards its high utility in protection of civil populations, where countermeasures would be stockpiled and then distributed, implying substantial delays and requiring efficacy many hours after the event of radiation. We now have a very strong position in the coming competition for radiation countermeasures for protection of general population initiated by the Department of Health and Human Services (HHS)."

Acute Radiation Syndrome (ARS), also referred to as radiation sickness, is an acute illness caused by irradiation of the entire body (or most of the body) by a high dose of penetrating radiation in a relatively short time period. Such exposure can result in the depletion of hematopoietic stem cells and progenitors, leading to severe neutropenia (low levels of neutrophils, a type of white blood cell) and thrombocytopenia (low platelet count). Severe neutropenia increases the risk of sepsis and death due to opportunistic infections, while thrombocytopenia increases the risk of hemorrhage and death due to bleeding. Both conditions are likely to be major contributors to mortality in untreated individuals exposed to doses of radiation that affect the hematopoietic system.

In the Company's recent experiment, five groups of 10 rhesus primates received 5 Gy (approximately 20% lethal dose) of gamma radiation. The control group received a placebo, while the four experimental groups received a single intramuscular injection of Protectan CBLB502 at one of the following times: 1, 16, 24 or 48 hours after irradiation.

No mortality was observed in CBLB502-treated groups after 30 days, while 20% mortality was observed in the control group.

The duration and occurrence of severe thrombocytopenia was strongly reduced by CBLB502. The average number of severe thrombocytopenia ( < 50,000 platelets/ul) days per monkey was drastically reduced from 4.3 in control group to 0.6-1.5 in all four CBLB502-treated groups. Thrombocytopenia has been shown to be the best predictor of primate post-irradiation mortality in recent studies.

In addition, duration and occurrence of severe neutropenia was also reduced by CBLB502. For example, an average number of days of extremely severe neutropenia ( < 100 neutrophils/ul) per monkey was reduced from 2.7 in control group to 0.3-1.5 in experimental groups.

Protectan CBLB502 is undergoing an accelerated development program under the FDA two-animal rule, which requires demonstrations of efficacy in two animal species and only safety in humans. The Company recently announced the completion of Good Manufacturing Practices compliant (cGMP) manufacturing of Protectan CBLB502 and plans to submit an Investigational New Drug (IND) application to the FDA for a human safety study this year.

Cleveland BioLabs submitted Protectan CBLB502 in response to a Request for Information (RFI) from HHS in July 2007, which noted the agency's intention to pursue initial acquisition of 100,000 treatment courses of a medical countermeasure for neutropenia arising as a consequence of ARS. The RFI further stated that there would be options for up to an additional 100,000 treatment courses to meet the US Government's requirement of at least 200,000 treatment courses.

Cleveland BioLabs also submitted CBLB502 to the Department of Defense (DoD) in response to a Request for Proposal (RFP) for medical radiation countermeasures to treat gastrointestinal effects of acute radiation syndrome. The RFP award would provide funding for development of the countermeasure through FDA approval, leading to purchase of up to 500,000 doses, thereafter. The Company expects the DoD to make its decision on the RFP this year.

Medical applications for Protectan CBLB502 include reduction of radiation therapy side effects in cancer patients and ischemic diseases involving lack of blood flow to certain parts of body such as acute organ failure, heart disease and stroke.

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, 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

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 periodic filings with the Securities and Exchange Commission.

Rachel Levine
Director Corporate Development & Communications
Cleveland BioLabs, Inc.
T: (646) 284-9439