Although the waning Ebola outbreak had Big Pharmas struggling to find volunteers for their Ebola vaccine trials, two new Phase II trials are going forward. GlaxoSmithKline ($GSK) will take its candidate to Senegal, while Johnson & Johnson ($JNJ) and partner Bavarian Nordic will test their vaccine in France and the U.K.
While the outbreak has abated in recent months, there has been a resurgence in Liberia, which was declared Ebola-free in May. Two people have died and 120 remain under observation, Al Jazeera reported. In West Africa, 30 cases were confirmed in the week of July 5, the highest number since mid-May.
"Vaccines play an essential role in outbreak situations, and both the clinical and the manufacturing experience we gain through this accelerated development represent an important piece of work in the combined efforts to ensure preparedness against Ebola, now and in the future," said Paul Chaplin, president and CEO of Bavarian Nordic in a statement.
|A volunteer gets GSK's Ebola vaccine during a Phase I trial at the University of Oxford.--Courtesy of the University of Oxford|
Both candidates use a prime-boost approach: The first dose provokes an initial response, and the second is a "booster" dose. GSK's ChAd3 is being tested with Emergent BioSolutions' ($EBS) MVA EBOZ as a booster. The trial will take place in Senegal, Reuters reported. The combo is undergoing a 38-patient Phase I trial at Oxford University.
The Oxford Vaccines Group will test Bavarian Nordic and J&J's candidate in a 612-person trial. The first volunteers have received their first prime or placebo doses. They will receive a boost or placebo dose on day 29, 57 or 85 of the trial.
While GSK and Emergent were the first to test one vaccine as a booster for another, Bavarian Nordic and J&J were the first to develop a prime-boost vaccine for Ebola. While the immune response could be improved by a booster, a two-dose vaccine could complicate mass immunization.
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