Cleveland Bio Labs, Inc. announced that CBLB502, a drug under development to treat exposure to radiation, has been granted Orphan Drug status by the US Food and Drug Administration (FDA) for prevention of death following a potentially lethal dose of total body irradiation during or after a radiation disaster.

The Orphan Drug Designation program provides orphan status to drugs and biologics which are defined as those intended for the safe and effective treatment, diagnosis, or prevention of rare diseases/disorders that affect fewer than 200,000 people in the US, or that affect more than 200,000 people but are not expected to recover the costs of developing and marketing the treatment.

Orphan Drug status qualifies CBLB502 for an accelerated review process, tax credits, financial assistance for development costs, and seven years of marketing exclusivity upon approval by the FDA for this indication. The designation also allows for a possible exemption from the FDA-user fee and assistance in clinical trial protocol design.

“We are very excited that CBLB502 has been assigned Orphan Drug status for its lead indication and look forward to working closely with the FDA as we complete development,” said Michael Fonstein, PhD, President and Chief Executive Officer of Cleveland Bio Labs.

In July 2010, CBLB502 was granted fast track status from the FDA for reducing the risk of death following total body irradiation during or after radiation disaster. There is currently no FDA approved medical countermeasure for this indication.

CBLB502 is a bio-engineered derivative of a microbial protein that potentially 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.

CBLB502 is being developed by Cleveland Bio Labs under the FDA's Animal Efficacy Rule. This approval pathway requires demonstration of efficacy in representative animal models and safety, pharmacokinetic, pharmacodynamic, and biomarker testing in healthy human subjects.

Data from 50 healthy human subjects in an initial phase I safety and tolerability study indicated that CBLB502 was generally well tolerated and that normalized biomarker results corresponded to previously demonstrated activity in animal models of lethal total body irradiation. Top line data from a second safety and tolerability study in 100 healthy subjects demonstrated that administration of CBLB502 resulted in a rapid and potent cytokine response, similar to that seen in the prior clinical trial and in previously conducted non-human primate studies and that CBLB502 was generally well tolerated.

Cleveland Bio Labs, 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.