Cleveland BioLabs, Inc announced the allowance from the US Food and Drug Administration (FDA) to begin phase-I clinical trials in human volunteers with Protectan CBLB502, a drug under development for the treatment for Acute Radiation Syndrome (ARS).

Protectan CBLB502 is being developed under the FDA's 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 two animal species and safety and drug metabolism testing in a representative sample of healthy human volunteers. Protectan CBLB502 has demonstrated activity as a radioprotectant in several animal species, including non-human primates.

The initial safety study will involve single injections of Protectan CBLB502 in ascending dose groups of six healthy volunteers each. Participants in the study will be assessed for adverse side effects over a two-week time period and blood samples will be obtained to assess the effects of Protectan CBLB502 on various biomarkers. The study is currently projected to take approximately six months to complete.

Protectan CBLB502 is a derivative of a microbial protein that reduces injury from acute stresses, such as radiation and chemotherapy, by mobilizing several natural cell protective mechanisms, including inhibition of programmed cell death (apoptosis), reduction of oxidative damage and induction of regeneration-promoting cytokines.

Earlier this year, Cleveland BioLabs received a contract from the Department of Defense valued at up to $8.9 million for the advanced development of Protectan CBLB502 as a medical radiation countermeasure.

Science Magazine published a peer-reviewed paper on Protectan CBLB502's radioprotective capabilities in the April 11, 2008 issue. The paper described Cleveland BioLabs's principle proprietary approach to protection of healthy tissues from a variety of potentially lethal cellular stresses and underscored Protectan CBLB502's potential as a radioprotector in both defense and medical settings.

Cleveland BioLabs, 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 Radiobiology Research Institute.