BARDA Signs Biodefense Contracts With GSK And Soligenix

Under a pair of agreements announced Sept. 19, the HHS unit will stockpile 60,000 doses of GSK’s inhalation anthrax treatment and will fund development of a treatment for GI acute radiation syndrome by New Jersey biotech Soligenix.

HHS’ Biomedical Advanced Research and Development Authority (BARDA) announced two contracts with private-sector firms Sept. 19 that are meant to bolster U.S. defenses against potential bioterrorism threats. BARDA signed an agreement with previous partner GlaxoSmithKline PLC to stockpile its inhalation anthrax treatment raxibacumab, and also contracted with Soligenix Inc. to finance development of a medical countermeasure against gastrointestinal acute radiation syndrome (GI ARS).

The agreement with GSK follows a 2011 transaction in which the multinational pharma received a two-year, $38.5 million grant to support development of an experimental antibiotic (GSK2251052) against biothreat pathogens such as Yersinia pestis and Bacillus anthracis (Also see "Deals Of The Week: GlaxoSmithKline/BARDA, Evotec/Roche, F-Star/Merck Serono" - Pink Sheet, 12 Sep, 2011.). According to GSK, the new agreement for raxibacumab follows a 2009 arrangement under which the government stockpiled 65,000 doses of the treatment then being developed by Human Genome Sciences Inc., which was acquired by GSK in 2012 (Also see "HGSI Gets Slightly Increased Buyout Bid, Accepts GSK Offer Of $3.6 Billion" - Pink Sheet, 16 Jul, 2012.).

Now, BARDA has signed a four-year agreement with GSK to acquire 60,000 doses of raxibacumab, a monoclonal antitoxin approved by FDA in December 2012 to treat inhalation anthrax infections in adult and pediatric patients, at a value of approximately $196 million. The antitoxin is approved to treat infections caused by exposure to Bacillus anthracis and also as prophylaxis against the infections when alternative therapies are not available or appropriate.

GSK said raxibacumab has no brand name and the pharma has no plans for any commercial use of the product. It is not approved in any other country. “At this time, raxibacumab has not been submitted for regulatory approval anywhere else in the world,” a GSK spokesperson said in an email. “GSK is committed to working in partnership with governments worldwide to provide emergency preparedness measures and help protect citizens against a number of different health threats including infectious diseases and bioterrorist ‘intentional diseases’.”

Raxibacumab’s efficacy was established on the basis of five animal-model studies of inhalation anthrax where the antitoxin demonstrated an improved survival rate when used as monotherapy or in combination with antibiotics. It also has been evaluated for safety at the recommended dose in 326 healthy human volunteers, GSK said. The most frequently reported adverse reactions, occurring in 1.5% or more of the subjects, were rash, extremity pain, itching and somnolence.

GSK2251052, being funded under the 2011 grant, is an antibiotic targeted at the bacterial enzyme leucyl tRNA synthetase (LeuRS) to potentially treat bubonic plague and anthrax infections. A boron-based, Gram-negative systemic antibiotic licensed by GSK from Anacor Pharmaceuticals Inc. in 2007, the candidate is in Phase II study in ventilator-associated pneumonia and Phase III for complicated intra-abdominal infections [See Deal].

ARS Treatment Has FDA Orphan, Fast-Track Status

Also on Sept. 19, Princeton, N.J.-based Soligenix announced a $26.3 million contract with BARDA to help finance the development of OrbeShield (oral beclomethasone 17,21-diproprionate, or oral BDP) as a medical countermeasure against GI ARS. ARS is caused by toxic radiation exposure and involves several organ systems, Soligenix said, including the bone marrow, gastrointestinal tract and later the lungs. Acute GI injury due to high doses of radiation can cause death in five to 15 days.

The contract begins with a two-year base period and includes a pair of contract options that could extend the arrangement to five years. The funding will pay for preclinical and manufacturing development activities to advance OrbeShield through FDA approval.

The candidate is formulated for oral administration as two tablets, one which releases BDP in proximal portions of the GI tract and another that releases BDP in distal portions of the tract. BDP is the active pharmaceutical ingredient, marketed worldwide since the early 1970s, in inhalable therapies for allergic rhinitis and asthma.

Soligenix said FDA has approved an IND for OrbeShield and granted the candidate orphan drug and fast track status. Oral BDP has been administered safely to more than 350 human subjects across multiple studies to date, and also is being investigated for other inflammatory GI disorders such as pediatric Crohn’s disease, radiation enteritis and chronic Graft-versus-Host disease.