Federal regulators have shut down PharmAthene's anthrax vaccine program.
The Annapolis biodefense company said it has received notification of the clinical hold from the Food and Drug Administration, but was not given a reason.
Within 30 days, the company said, it expects more details from the FDA. In the meantime, PharmAthene will continue furnishing analytical data from its recently manufactured lot of material for the phase 2 clinical trial.
The company had expected to launch the trial this year, but has not enrolled any of the 300 expected subjects.
When the company announced the news on Aug. 10, its stock price fell 19.7 percent. It since has climbed back 7.6 percent as of Thursday afternoon.
PharmAthene in June reported progress in manufacturing SparVax at full commercial scale. The company said it had finished final testing and prefilled syringes of the experimental vaccine were ready for clinical trials.
PharmAthene's technology uses E. coli, which results in “a more robust manufacturing process and the capability of annually producing more than 150 million ... vaccine equivalent doses of bulk drug substance,” according to a company statement — a much higher yield compared with the first-generation anthrax vaccine.
It's being developed for use as both a pre-exposure prophylactic and post-exposure, in conjunction with antibiotic treatment.
For years, PharmAthene has been among a handful of companies — including Emergent BioSolutions of Rockville — trying to develop a next-generation anthrax vaccine. A new vaccine would require fewer doses and last longer than the only currently approved vaccine, BioThrax, which is manufactured by Emergent.
In April, PharmAthene reported that results from both human clinical trials and non-clinical animal studies suggest that SparVax confers 90 percent and almost 100 percent protection, based on six- and 12-month booster doses, respectively.
So far, one phase 1 and two phase 2 trials have been completed, involving about 770 subjects.
The federal government has helped subsidize development of SparVax. Two contracts from the National Institutes of Health in 2002 and 2003 provided up to about $128 million in funding, according to a company filing with the Securities and Exchange Commission. Through September 2013, PharmAthene was funded up to $62 million for the program. The company said it continues to seek more federal money.
PharmAthene and Emergent aren't the only Maryland biotechs working on a new anthrax vaccine. Last year, the federal Biomedical Advanced Research and Development Authority has awarded Vaxin, also of Rockville, a two-year, $14.7 million contract to help it develop a vaccine that could be given nasally, making administration easier and more widely available, as non-medical personnel could administer it.
The Vaxin contract could be extended for two more years and reach $21.7 million, according to the agency.
In other Maryland bioscience industry news:
Spherix reported that its experimental treatment for metabolic syndrome "significantly reduced the growth rate" of abdominal aortic aneurysms in mice that were prone to hyperlipidemia, or high blood levels of fat.
Risk factors for these aneurysms in people include age, gender, genetics, smoking, atherosclerosis, hyperlipidemia, high blood pressure and cerebrovascular disease, according to information from the Bethesda biotech.
“These study results further our goal of expanding the application of SPX106T to multiple indications where dyslipidemia has been suggested as a primary risk factor,” CEO Claire Kruger said in a statement. The treatment of these aneurysms "represents a potential new use for SPX106T. We are now exploring grant applications, possibly in conjunction with a pharmaceutical partner, as part of our plan to further develop SPX106T for this indication.”
Sanaria is working with a California company under a federal grant to advance the Rockville biotech's experimental malaria vaccine.
Antigen Discovery of Irvine won a three-year, phase 2 Small Business Innovation and Research award for about $2.5 million from the National Institute of Allergy and Infectious Diseases.
Researchers from the companies are collaborating to use Antigen's microarrays to identify biomarkers associated with the administration of Sanaria's malaria products, including its vaccine.
"By comparing the serum antibody profiles from vaccinees who are protected with those who are not, we aim to identify surrogate antibody biomarkers associated with sporozoite vaccine mediated protection," Philip Felgner, chairman of Antigen, said in a statement. "Such markers are a critically important component of vaccine development."
Stephen L. Hoffman, Sanaria's founder and chief scientific officer, called the project "an unprecedented opportunity to exploit [Antigen's] unique technology to advance our understanding of protective immunity against malaria, and thereby accelerate development and licensure of a highly effective malaria vaccine."