Cleveland BioLabs, Inc has completed recruitment of a total of 100 healthy volunteers in the second human safety study for CBLB502, a drug under development for the treatment of Acute Radiation Syndrome (ARS).

CBLB502 is being developed by Cleveland BioLabs under the US Food and Drug Administration's Animal Efficacy Rule to treat ARS or radiation poisoning from any exposure to radiation such as a nuclear or radiological weapon, dirty bomb, or from a nuclear accident. This approval pathway requires demonstration of efficacy in representative animal models and safety, pharmacokinetic, pharmacodynamic and biomarker testing in healthy human volunteers.

Evidence of CBLB502's mechanism of action and activity in animal models was published in Science Magazine in April 2008 (Science, 2008, vol. 320, pp. 226-230). Data from 50 human subjects in an initial phase-I safety and tolerability study indicated that CBLB502 was well tolerated and that normalized biomarker results corresponded to previously demonstrated activity in animal models of ARS.

The second safety study includs a total of 100 healthy human volunteers randomized among four dosing regimens of CBLB502. Participants in the study were monitored for adverse side effects and blood samples were obtained to assess the effects of CBLB502 on various biomarkers and to further characterize the pharmacokinetics of CBLB502.

Analysis of safety and biomarker data is ongoing. The primary objectives of this study are to gather additional data on safety, pharmacokinetics, and cytokine biomarkers in a larger and broader subject population in order to finalize an appropriate dose to take forward for the large, definitive human volunteer safety study.

The Biomedical Advanced Research and Development Authority (BARDA) of the Department of Health and Human Services supported the entire cost, of approximately US$ 1.3 million, of this clinical phase-1b human safety study as part of the contract.

Cleveland BioLabs 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.