With the Ebola virus ravaging West Africa and causing growing anxiety over the potential for outbreaks in Europe, America and elsewhere, drug developers are pressing to discover an effective treatment and develop a vaccine against the lethal hemorrhagic fever.
No drug is yet approved as safe and effective for treating or preventing Ebola. Current treatment for those stricken by the disease is to balance fluids and electrolytes, maintain blood pressure and oxygen, and treat complications. In Guinea, Liberia and Sierra Leone, where the disease has attained epidemic proportions, the death rate is about 70% of those infected.
As an emergency measure, ZMapp, developed by San Diego-based Mapp Biopharmaceutical, is being administered in some cases. For example, ZMapp was also given to two U.S. medical missionaries who recovered after contracting the disease in Liberia, where the disease has already claimed thousands of lives.
The experimental therapy is a cocktail drug combining three monoclonal antibodies. The company’s current molecular biology process uses tobacco plants to produce each antibody separately, and then must get a certificate of analysis for each before combining them into the combination drug ZMapp.
The company is working to boost yields from its plant-based production method, and ecently joined with another producer to see if yields be would boosted by using an animal-based biotech production method, which employs genetically-modified CHO cells from Chinese hamster ovaries cultivated in sterile tanks. The plant production method, carried out by the Reynolds tobacco company’s Kentucky BioProcessing subsidiary, is faster and cheaper, but not as suitable for large-scale production as more conventional biotechnology methods.
ZMapp is being tested in animal experiments done by the US Army Medical Research Institute of Infectious Disease, with assistance from the Bill and Melinda Gates Foundation. The animal tests are designed to see if the drug has the same effects at lower doses, since supplies of ZMapp are very limited.
On September 2, Mapp Biopharmaceutical received a $24.9 million contract from the U.S. Department of Health and Human Services to assist the company’s manufacturing and non-clinical activities. Part of the 18-month contract will also bring HHS technical support for the drug company’s effort to manufacture enough of the drug to support human safety clinical studies. The company had planned to start clinical studies in 2015, and is now working to accelerate its efforts to win FDA approval.
In addition, two Ebola-preventing vaccines have started clinical trials in humans. Even if early results from those tests are positive, no vaccine is expected to receive FDA approval and reach the marker until next year at the earliest.
At the National Institutes of Health (NIH), Phase 1 safety and effectiveness clinical trials in healthy adults have begun for an investigational vaccine jointly developed by the National Institute of Allergy and Infectious Diseases (NIAID) and GlaxoSmithKline, and for an experimental Ebola vaccine from the Public Health Agency of Canada. The NIAID-GSK vaccine will also receive clinical trials in the UK and several African nations. Further anti-Ebola products are likely to follow in starting clinical trials, perhaps as early as next year.