Geneva ¦ July 31, 2015 - the results of an interim analysis of the clinical phase IIIconcerning the efficacy of the Ebola VSV-EBOV (Merck, Sharp & Dohme) vaccine inGuinea showed that this vaccine is very effective.
The Council of surveillance and data - - independent body of international experts -security, who conducted this study, recommended to continue this test. Thepreliminary results of these preliminary analyses are published today in the Britishjournal The Lancet.
"It is a very promising advance," said Margaret Chan, Director-general of the WorldHealth Organization. "We got it thanks to the Guinean Government, people living incommunities with many partners in this project. An effective vaccine will be a veryimportant additional weapon in the fight against the current outbreak of Ebola andfuture outbreaks", she added.
Although so far the vaccine appears to be effective in all vaccinees, required moreconclusive data to determine whether the vaccine can confer a "herd immunity" toentire populations. To this end, the national authority of regulation of medicalproducts and the national Committee of ethics of Guinea approved the continuationof the trial.
4000 people in contact with patients participated in the trial
"It is the gift of Guinea in West Africa and the world," said Dr. Sakoba Keita, nationalcoordinator of the response to Ebola in Guinea. "Thousands of volunteers fromConakry and other regions of lower Guinea, but also many physicians, managers ofdata and mobilizing community Guineans, have contributed to find a line of defenseagainst this terrible disease", he added.
"The so-called vaccination method"in belt"adopted for the test is based on thestrategy for the eradication of smallpox", said John - Arne Røttingen, Director of theDivision of infectious disease at the Norwegian Institute of public health andChairman of the Steering Group of the study. "Our basic assumption is that byvaccinating all persons who have been in contact with an infected, it creates a"belt"ofprotection that allows to stop the spread of the virus. This strategy allowed us tomonitor the spread of the epidemic in Guinea, and will be a way to extend thisintervention of public health in the clinical trial."
The VSV-EBOV in Guinea vaccine test began in affected communities on March 23,2015 to assess the effectiveness and safety of a single dose following a vaccinationstrategy in belt. To date, more than 4,000 close contacts of almost 100 patients withdisease Ebola virus, including members of the family, neighbors and colleagues, havewillingly participated in the test.
Randomization for this test stopped July 26 to allow all people at risk receive thevaccine immediately, and to shorten as much as possible the time necessary to gathermore conclusive data to ultimately approve the product.
So far, 50% of the "belts" have been vaccinated three weeks after the identification ofa patient infected in order to make a comparison with the "belts" that were vaccinatedimmediately. This is now completed. In addition, the test will now include elderlysubjects aged 13 to 17 and possibly individuals aged 6 to 12 years, on the basis ofnew data on the safety of the vaccine.
The same vaccine tested also on stakeholders in first line
"Alongside immunization in belt, we are also a test of the same vaccine on first lineresponders", said Bertrand Draguez, medical director at Médecins sans Frontières (MSF). "These people have worked tirelessly and risked their lives every day to take care of sick people. '' If the vaccine is effective, we already protect them against thevirus. Given the level of efficiency, all affected countries should immediately start andmultiply the belt vaccinations in order to break the chains of transmission and tovaccinate all their stakeholders in the front line to protect."
The test is implemented by the Guinean authorities, who, Médecins sans Frontièresand the Norwegian Institute of public health, with the support of a broad partnershipcomposed of international and national organizations.
"It is a remarkable result that shows the power of equitable international partnershipsand flexibility," said Jeremy Farrar, Director of the Wellcome Trust, one of the donorsfor the test. "This partnership also shows that this essential work is possible at theheart of a terrible epidemic. It should change the way the world responds to thethreats that are