Fight Against Ebola Gaining Ground As Vaccines Pass Tests, WHO Says

The World Health Organization today optimistically announced progress in the search for efficient vaccines to fight the Ebola virus. Tests conducted so far show acceptable safety profiles, and public-private vaccine alliance Gavi has committed to fund Ebola vaccines.

Marie-Paule Kieny, WHO assistant director-general, said in a press briefing today that 2014 “will be remembered as the year when the Ebola virus challenged humanity,” but 2015 will be remembered as the year humanity used its best resources to fight back. She said there has been no holiday for people on the quest for vaccines, but long days and sleepless nights.

According to the latest WHO situation report, there have been over 20,000 “confirmed, probable, and suspected cases” of Ebola in Guinea, Liberia and Sierra Leone, “with more than 8,000 deaths.” Deaths are under-reported, according to WHO.

The audiofile of today’s briefing is available here [mp3].

Following the second high-level meeting on Ebola vaccines access and financing, convened by WHO on 8 January, Kieny and professor Helen Rees of the University of Witwatersrand, South Africa, chair of the meeting, commented on the the conclusions of the meeting.

According to the WHO, the purpose of the high-level meeting was to: “provide an update on the emerging safety and immunogenicity results of Phase I clinical trials; review the candidate Ebola vaccines pipeline; review manufacturers’ plans to extend the safety database; review the status of preparation for Phase III efficacy trials in the three most-affect West African countries; and provide an update on the decision of the Vaccine Alliance’s Board to financially support the introduction of Ebola vaccines.”

Kieny said two vaccines (from Merck US, and GlaxoSmithKline – GSK), going through their third phase of testing, have acceptable safety profiles and would be continuing their journey towards evaluation. She also noted that a number of potential vaccines at various stages of developments were lining up. In particular, she cited vaccines from the United States, Russia, and China. According to Kieny, Johnson & Johnson is also planning to engage in efficacy testing for a vaccine.

According to Kieny, in the next two to four weeks, data on immunogenicity of the tested vaccines will be available, which will allow analysis of which vaccines perform better according to different criteria.

Rees said the meeting underlined remarkable progress made in the development of Ebola vaccine, which she said were “unprecedented” in the development of any vaccine. She also underlined parallel measures in addition to current clinical developments, including a collective effort by many partners. She cited for example the work of regulatory authorities in the US, the European Union and the affected countries, so that no block could be caused by the regulatory approval process.

Rees also noted the decision by Gavi’s board to support the funding of Ebola vaccines.

According to a Gavi Alliance release, on 11 December, the Gavi Board declared that the alliance was ready to begin procurement as soon as WHO recommends a vaccine for use.

The Gavi Board agreed “to purchase millions of doses of an Ebola vaccine to support large-scale vaccination efforts.” According to the release, “The Gavi Board endorsed plans that could see up to US$ 300 million committed to procure the vaccines, to be used to immunise at risk populations in affected countries.”

In terms of production capacity, Kieny said GSK provided numbers on their production capacity in the fall, and “it seems” they could have a few million doses by the middle of this year. Merck could potentially deliver tens of millions doses during 2015, she said, while Johnson & Johnson has a robust production capacity for the two components of its vaccine.

However, it all depends on the dose level, she said, because if more vaccine is needed per injection, that would proportionally decrease the number of injections available.

Image Credits: Flickr – NIAID