Meets Critical Development Milestone on Path to Potential Commercialization

BUFFALO, NY -- (Marketwire) -- 06/03/09 -- Cleveland BioLabs, Inc. (NASDAQ: CBLI) today announced that dosing of healthy volunteers in the initial human safety study for CBLB502, a drug under development for the treatment for Acute Radiation Syndrome (ARS), has been completed.

CBLB502 is being developed under the U.S. Food and Drug Administration's (FDA) Animal Efficacy Rule to treat radiation injury following exposure to radiation from nuclear or radiological weapons, or from nuclear accident. This approval pathway requires demonstration of efficacy in representative animal models and safety and drug metabolism testing in healthy human volunteers. Demonstration of specific activity in humans is based on biomarkers that directly reflect the mechanism of the drug's action. Evidence of CBLB502's mechanism of activity and efficacy in animal models was published in Science Magazine in April, 2008 (Science, 2008, vol. 320, pp. 226-230).

The initial human Phase I safety and tolerability study involved single injections of CBLB502 in ascending-dose cohorts of six healthy volunteers each. Participants in the study were assessed for adverse side effects over a 28-day time period and blood samples were obtained to assess the effects of CBLB502 on various biomarkers.

Data from 50 subjects indicates that CBLB502 was well tolerated and that normalized biomarker results corresponded to previously demonstrated activity in animal models of ARS. A pattern of biomarker production was observed consistent with those patterns seen in animals during mitigation of radiation-induced injury by dosing with CBLB502. As part of the development of CBLB502, this study will be followed by a second, larger safety study in healthy human volunteers, which will be based on the results of the initial study.

"With initial human data in hand, we have reached a significant corporate milestone in our development towards potential commercialization," noted Michael Fonstein, Ph.D., Chief Executive Officer and President of Cleveland BioLabs. "While we have collected extensive data on CBLB502 in animal models of ARS over the past six years, this trial was critical to obtaining an understanding of the overall tolerance and drug activity in humans. We will be compiling our final data analysis for submission to the FDA and working with the appropriate representatives of that agency to determine the exact protocol for the next human safety study."

The initial human Phase I safety and tolerability study was partially funded by the Company's existing contract (valued at up to $13.3 million) from the Biomedical Advanced Research and Development Authority (BARDA) of the Department of Health and Human Services for certain elements related to the development of CBLB502.

About Cleveland BioLabs, Inc.

Cleveland BioLabs, Inc. is a drug discovery and development company leveraging its proprietary discoveries around programmed cell death to develop treatments for cancer and protection of 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 Radiobiology Research 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. The Company's 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 the Company's periodic filings with the Securities and Exchange Commission.