Merck-NewLink Ebola vaccine Phase III trial to start March 7

[March 05, 2015]  GENEVA/LONDON (Reuters) - Final stage of testing of an experimental Ebola vaccine being developed by Merck and NewLink Genetics will begin in Guinea on March 7, the World Health Organization said on Thursday.

Signaling global health authorities' determination to push ahead with vaccine trials despite a sharp drop in cases in the West Africa epidemic, the WHO said a second shot, developed by GlaxoSmithKline will be tested "in a sequential study, as supply becomes available".

More than 23,900 confirmed and suspected cases of Ebola have been reported since the outbreak began in December 2013, including some 9,800 deaths. Nearly 500 health workers have been among the dead in what is the worst Ebola epidemic in history.

All three worst-hit countries - Guinea, Liberia and Sierra Leone - aim to conduct Phase III final-stage clinical trials of experimental vaccines. Liberia is already testing both the GlaxoSmithKline and Merck-NewLink vaccines, while Sierra Leone is expected to announce plans soon.

But a steep decline in new Ebola cases in recent weeks will make it far harder to prove whether experimental vaccines work, as the vaccine's effect will be hard to establish.

However Margaret Chan, the WHO's Director-General, signaled her determination.

"There has been massive mobilization on the part of the affected countries and all partners to accelerate the development and availability of proven interventions," she said in a statement.

"If a vaccine is found effective, it will be the first preventive tool against Ebola in history."

(Reporting by Tom Miles and Kate Kelland; Editing by Louise Ireland)

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