Ebola virus (blue) budding from an infected monkey kidney cell (yellow).

Ebola virus (blue) budding from an infected monkey kidney cell (yellow).

NIAID

Make haste on experimental Ebola treatments, urges WHO group

Researchers and health professionals should fast-track extraordinary efforts to give people unproven treatments and vaccines in locales hard hit by Ebola, more than 200 experts attending a World Health Organization (WHO) forum recommended today.

“We have to change the sense that there is no hope in this situation to a realistic hope,” said WHO Assistant Director-General Marie-Paule Kieny, who spoke at a press conference with two other attendees of the consultation. More people have become sick and died from Ebola in the last few months than in the 4 decades since the virus was discovered, she noted.

No treatments or vaccines exist that have proved their worth against Ebola, and when the outbreak in West Africa first started to receive attention 2 months ago, many dismissed the idea that biomedical interventions could help. As the outbreak has grown into what some are calling a full-blown epidemic—despite containment efforts that have proved effective in the past—the idea of rolling out experimental treatments and vaccines has moved to center stage.

The 2-day WHO consultation, which mixed researchers with ethicists, legal and regulatory authorities, and health officials from affected countries—reached consensus that blood from people who had survived an Ebola infection, as a “matter of priority,” could be used to treat infected people. “There was a consensus that this has a good chance to work and also this is something that can be produced now from the affected countries now,” Kieny said. “There are many people now who are convalescent, who survived and doing well.”

The hope is that whole blood or purified plasma will contain Ebola antibodies and possibly other immune warriors that can combat the virus. Kieny stressed that the international community urgently must help affected countries do blood removal, purification, and reinjection safely. Some locales have already started using convalescent serum, she said. The treatment has never been formally tested, but whole blood was used in eight people in the Democratic Republic of the Congo during the 1995 outbreak in Kikwit; just one died.  

As early as November, researchers may have enough data from small human studies of two Ebola vaccines to warrant offering them to health care workers and other frontline staff caring for Ebola patients, Kieny said. “This will allow their utilization in the infected countries immediately,” Kieny said. “This is real. This is going into the field. This is not staying in the laboratory.”

Traditionally, regulatory agencies tightly regulate trials of vaccines as they move from small, phase I studies that assess safety and immune responses to phase II studies that essentially ask the same question in larger numbers of people. Phase III efficacy studies test whether products work, usually with a placebo control group.

In this current emergency scenario, however, the vaccines may move directly from phase I into loosely organized phase II/III studies—with little regulatory oversight—that have no placebo control but try to gather data that allows comparisons of vaccinated and unvaccinated recipients who have similar health risks.

“It’s absolutely unprecedented, there is no doubt,” Kieny said. “Everybody has to move as quickly as possible and this includes the regulators.” She said that while regulators and ethics committees are trying “to preserve, as much as possible, safety,” the goal will be to allow development to move very quickly.

Only about 10,000 doses of the vaccines will be available by the end of the year, so there is no possibility of their wide distribution. Kieny explained that this is something of a mixed blessing, as vaccines in the past have proved safe and effective in small studies but caused harm when widely used. “We must be cautious about that and rollout must happen as quickly as possible but step by step.”

Press conference participant Oyewale Tomori, a virologist at Redeemer's University in Redemption City, Nigeria, urged that attention to the consultation not detract from the fact that we know how to stop Ebola transmission. “If we’d done proper infection control in those other countries where it occurred we wouldn’t be having the same problem we’re having now,” said Tomori, whose own country has had trouble containing spread, in part because infected people dodge the health care system.

Samba Sow, director general of the center for vaccine development in Bamako, noted at the press conference that the experimental vaccines could indirectly help control the epidemic by calming fears of health care workers. “Health care workers now are scared to come to the health center and take care of patients,” said Sow, whose center will soon begin phase I tests of an Ebola vaccine. He spoke of his own risk from taking the blood of 18 patients with suspected infections, including four he had to autopsy. (Mali, which shares a border with heavily affected Guinea, has yet to have anyone test positive.) “If there’s a potential vaccine coming in I have to be first to get this,” he said. “Plus it will show transparency, it will show confidence, it will show respect to the rest of the community.”

*The Ebola Files: Given the current Ebola outbreak, unprecedented in terms of number of people killed and rapid geographic spread, Science and Science Translational Medicine have made a collection of research and news articles on the viral disease freely available to researchers and the general public.

*Update, 6 September,11:48 a.m.: This article was updated to includes links and clarify testing practices.