The trials of experimental Ebola vaccines and drugs have ended in “questionable results or outright failure” admits Sciencemag in an unusually forthright review of the trials.
Apart from one trial, the results of Ebola vaccine and drug trials have not even been considered worthy to publish in scientific literature – and for the very reason that their study design made it impossible to draw any conclusions about their effectiveness.
The experimental Ebola vaccine and drug trials used a new design that meant their effectiveness could never be proven. The experimental Ebola drugs were given without using a comparison group of patients given a placebo. Assigning patients at random to drugs or a placebo is the gold standard for testing whether drugs work and are not causing harm.
The New England Journal of Medicine refused to publish the results of a TKM Ebola vaccine study because the study design made it impossible to determine whether the vaccine was effective or not.
Peter Horby, a researcher from the University of Oxford, who headed the TKM study, funded by the Wellcome Trust admitted the trials resulted in “the almost complete absence of any data on treatment effects.”
One study involving a drug called brincidofovir given to patients without any control group was shut down at the end of January 2015 after all of the first four patients died, according to the Wall Street Journal.
A Merck vaccine trial using a confusing and new ring study design “yielded data that were not deemed strong enough to lead regulatory bodies to license the vaccine”, admit Jon Cohen and Martin Enserink at Science Mag.
But the Merck vaccine trial results were the only ones published and these stated that there were 27 confirmed cases of people getting Ebola from the vaccines.
Getting Ebola is, in fact, listed as the most common adverse event from the Merck vaccine. This is a clear, unambiguous statement published online.
“As of July 20, 2015, a total
of 43 serious adverse events had been documented among
eligible and consenting trial participants, including
27 confirmed cases of Ebola virus disease (see appendix).
Apart from Ebola virus disease, the three most common
serious adverse events were suspected, unconfirmed Ebola
virus disease (three cases), episodes of febrile illness (three
cases), and road traffic accidents (three cases). 16 deaths
occurred: 15 from Ebola virus disease and one from cardiac
arrest. ” (Results section, page 7 and 8)
W.H.O . is the main sponsor of the trial which took place in Guinea.
However, Merck’s record of infecting only some of the patients with Ebola is a huge improvement on the the 100% death rate recorded among patients recorded who received brincidofovir.
In comparison to the 100% lethality of brincidofovir, Merck’s Ebola vaccine is indeed a success story.