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Nobody Is Sure Why A Promising Ebola Drug Trial Ended

The company producing the new Ebola treatment suddenly pulled out of Liberia, leaving researchers confused.

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NAIROBI — A year after the onset of the worst Ebola outbreak in history, Liberia has become ground zero for something equally unexpected — a historic public health experiment.

The U.S. National Institutes of Health (NIH) is sponsoring a randomized control trial of vaccines that researchers hope might prevent the deadly disease in patients who receive it. The trial began in Liberia on Feb. 2 with 600 patients and plans to scale up to nearly 30,000.

Liberian officials have claimed that volunteers in that trial are not receiving cash in exchange for participation. "We are not paying any Liberian a dime for volunteering to take the Anti-Ebola Trial Vaccination," a co-investigator of the Ebola vaccine trial, Dr. Stephen B. Kennedy, said Monday, according to a Liberian government news wire.

But a statement from the National Institute of Allergy and Infectious Disease (NIAID) emailed to BuzzFeed News on Wednesday said participants were currently receiving "$40 in cash for their first visit, which involves an injection and a blood draw." The NIAID is part of the NIH; its researchers are conducting the trial in partnership with Liberian researchers.

"Participants…are compensated for inconvenience (transportation; time and wages lost)," the statement, issued in response to a query from BuzzFeed News, said. "Compensating clinical study volunteers for inconvenience is standard clinical practice for studies that are conducted either in the United States or abroad."

The NIH trial launched in Liberia earlier this month, at a time when the country's Ebola case load had already dropped dramatically. On the day the trial launched, there was only one new laboratory-confirmed case of Ebola in Liberia.

Dr. Anthony Fauci, who oversees the study for the NIH, acknowledged that the drop in cases may make it impossible to draw any conclusions about the vaccine's ability to prevent Ebola but that it may help fast-track future studies or uses of the drug in the event of another outbreak.

Fauci said the study, which received its approvals in the fall when case numbers were much higher, will allow researchers to determine whether the vaccine is safe for use in the event of another outbreak.

But trials for another treatment undergoing a trial in Liberia — a drug meant to treat Ebola-positive patients — were stopped last week in part because of the low case load.

The trial of the drug brincidofovir, meant to treat rather than prevent Ebola, had already begun in Liberia's capital of Monrovia when Chimerix, the company that produced the drug, pulled out of the trial at the end of January. The clinical trial partners decided to end the trial on Feb. 3.

Peter Horby, who led the University of Oxford research team conducting the study, called the drug company's decision "a bit abrupt."

Horby said the research consortium — which included the trial funder, an independent British medical research organization called the Wellcome Trust, and Doctors Without Borders, whose clinics were being used as research sites — had discussed adding additional sites to the study in the event that case numbers at its first site dropped too low.

Horby said the research team had received and stored enough doses of brincidofovir in Liberia to scale up to additional sites but that the drugs would have to be destroyed following the Chimerix withdrawal.

Fewer than 10 patients had already been enrolled in the trial, Horby said. He said confidentiality rules for clinical trials did not allow him to discuss how the patients felt about the study's premature termination.

The trial was part of global efforts to fast-track experimental therapies. Horby's team began the trial in January — compressing what he said is typically 18 months of preparation for a clinical trial into just two months.

Joseph Schepers, a Chimerix spokesman, would not comment specifically on the company's conversations with the FDA. He said in an email to BuzzFeed News that its decision to withdraw from the trial was made after discussions with "the FDA and other federal agencies, as well as international regulatory and public health groups, and against the backdrop of a rapidly diminishing pool of patients with Ebola Virus Disease in Liberia."

Dr. Charlie Weller, a senior portfolio developer at the WellcomeTrust, also said she didn't think the low case numbers fully accounted for the drug company's withdrawal.

"We don't know exactly the reason why the company pulled out. That would be something to ask them," Weller said. "All we know is that there was communication or discussion with the FDA…Obviously something changed."

"There's a lot of people who have been working … their day job and [have] done the Ebola work throughout the night," she added. "So it is disappointing. It would be good to understand the reasons."

Horby said the research team was similarly unaware of the reasons behind the decision. "Certainly their discussions with U.S. FDA were critical in that decision. But we were not party to that decision and I don't know the basis of the discussions between the Food and Drug Administration and the drug company that precipitated that decision," Horby said.

Horby said the FDA's involvement, which was "really about approving export of the drug to Liberia," had essentially already ended by the time the trial began in early January.

"We had all the drugs on site," Horby said. "As far as I'm aware there was no new data about the safety or the effectiveness of the drug that was behind the FDA's concerns. So I don't know what the FDA's concern was and why it came so late."

The FDA refused to comment on the matter, citing legal protocols, and referred questions to the drug company. Schepers, the Chimerix spokesman, did not answer repeated emails requesting more information about the company's conversations with the FDA.

Chimerix also announced in late January that it would not participate in "any future trials" of brincidofovir as an Ebola treatment — a move Horby said was "unusual."

"Unless you've demonstrated the drug doesn't work or it's not safe in that patient group, then the only other reason really would be commercial reasons, such as it's not in the company's commercial interest to pursue that drug for that particular disease," Horby said.

In November, the company raised $122 million for further research with the drug in a November stock offering. But Ebola has brought volatility to its share value. In October, in the hours following the announcement of the death of a Liberian-American treated for Ebola with brincidofovir in Texas, Chimerix stock tumbled 8.1%. Last week, as news of the clinical trial hit the media, stock prices fell 11%.

Brincidofovir was originally developed as a treatment for small pox. Its development has been supported by $103 million, since 2011, in funding from the Biomedical Advanced Research and Development Authority, a division of the U.S. Department of Health and Human Services.

Following the publication of this article, a spokesperson for the FDA contacted BuzzFeed News and said by telephone that the FDA played no oversight role in the Liberian clinical trial.

Dr. Luciana Borio, acting deputy chief scientist at the FDA, also sent a statement to BuzzFeed News by email. "[The] FDA did not approve this trial. [The] FDA evaluates proposed clinical trials when sponsors seek permission to conduct such trials by submitting investigational new drug (IND) applications," she said.

Borio said that Chimerix had not submitted an IND application.

Public documents issued by Chimerix said the FDA had authorized a study of its drug for patients confirmed to have Ebola. The company also said the study authorization followed the use, through emergency IND procedures, to treat individuals with Ebola prior to the trial. At least one patient treated in the United States for Ebola received brincidofovir.

Jina Moore is the global women's rights correspondent for BuzzFeed News and is based in Berlin.

Contact Jina Moore at jina.moore@buzzfeed.com.

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