US, Liberia begin clinical trial of Ebola drug ZMapp

United States and Liberian researchers have started a clinical trial to test the safety and effectiveness of the Ebola drug ZMapp, an experimental treatment that has already been tried in a handful of Ebola patients.

The trial, a joint effort by the Liberian government and the National Institute of Allergy and Infectious Diseases (NIAID) in the U.S., is being conducted in Liberia and the U.S. among adults and children infected with Ebola, NIAID said on Friday.

Although ZMapp, a cocktail of antibodies made in tobacco plants, has been used on a humanitarian basis in nine infected patients, there was no way to tell whether the treatment offered a statistically significant benefit, Dr. Anthony Fauci, director of the NIAID, said in a statement.

NIAID said Friday that half the participants in the trial will receive three ZMapp injections once a day for three days, along with supportive treatment. The other half, the control group, will only receive supportive treatment, including intravenous fluids, medication for any other infections they get and therapy to maintain blood pressure and sufficient oxygen intake. The goal is to enroll 100 patients in each group.

Each participant will be monitored for up to a month after hospital discharge, including any follow-up outpatient treatment, and researchers then will compare how well the two groups fare. 

Fauci said the randomized trial should provide the scientific evidence needed to show whether ZMapp is safe and effective, and whether it can be used in the current outbreak in West Africa and in future outbreaks.

The trial will enroll adults and children admitted to Ebola treatment units in Liberia, health care workers infected with Ebola virus in West Africa who have returned to the U.S. for treatment, and adults and children who may have acquired Ebola in the U.S. through secondary transmission.

If the drug proves effective, it will become part of the standard of care and a new treatment will be randomly assigned to portion of the patients.

Other drugs to be tested include a treatment from Canadian drug maker Tekmira, the antiviral Favipiravir from Japan's Toyama Chemical Co, blood plasma collected from Ebola survivors, the drug BCX4430 from North Carolina-based BioCryst, and a treatment called AVI-7537 from Sarepta of Massachusetts.

The trial is expected to conclude in December 2016, although scientists say they may need to be flexible as the Ebola epidemic wanes.

Guinea, Liberia and Sierra Leone reported 99 new confirmed Ebola cases last week, down from 128 the previous week, the World Health Organization said on Wednesday.

The current outbreak is the worst in history. So far, the virus has infected nearly 24,000 people and has killed more than 9,600, according to the most recent WHO numbers.

Wire services