Glaxo quietly edges toward Ebola vaccine but clinical barriers remain

As Africa continues to experience the most severe Ebola outbreak in the disease's short history, the World Health Organization has deemed it ethical to offer unregistered interventions as potential treatments or preventive therapies, including investigational vaccines.

The announcement comes on the heels of news that GlaxoSmithKline ($GSK) may be able to deliver one such vaccine by 2015.

GSK acquired the vaccine candidate in the $325 million buyout of Okairos in May 2013. Now, Glaxo says it is working with the U.S. National Institutes of Health's Vaccine Research Center (VRC) to advance the development of the early-stage vaccine, which Glaxo says it has already evaluated in preclinical studies. In collaboration with the VRC, the drugmaker is now in talks with regulators to advance the vaccine to a Phase I clinical trial later this year.

"It is difficult to accelerate this process because of the many important steps that a candidate vaccine must go through to ensure that it is safe and effective," the company says in a statement on its website.

There are other huge clinical hurdles to testing Ebola drugs, especially a vaccine. For one, the disease is relatively rare and when an outbreak does strike, it tends to kill people quickly and burn out fast. This presents logistical problems for clinical trials, because it takes time to design and set up a trial and then enroll patients.

With Ebola, under no circumstances would researchers infect people with the disease to test a vaccine's protection in a clinical trial. Therefore, any clinical trial data would be based solely on safety in healthy volunteers.

Then there's the question of who would receive a vaccine. Scientists don't yet know where the Ebola virus originates--though the likely reservoir is believed to be bats--and it's also unclear how widespread the Ebola reservoir is. With zoonotic diseases like Ebola, a reservoir refers to a nonhuman animal in which a virus lives while waiting for new hosts to infect. What's more, experts have said that it's difficult to know whether an Ebola vaccine would be effective until years after it's administered.

Earlier this month, NIH said it expects to launch a clinical trial for an Ebola vaccine as early as September. The agency has revealed few details about the trial, and it's not clear whether the Glaxo vaccine is the jab in question.

According to WHO's latest numbers, released Aug. 13, the number of Ebola cases has climbed to 1,975, killing 1,069 of those--a 54% mortality rate.

- read more about Glaxo's Ebola vaccine efforts
- get FierceBiotech's take

Suggested Articles

A Lancet Infectious Diseases study shows antibody response persists for two years or more after a single shot of Merck’s rVSV-ZEBOV vaccine.

The partnership aims to make the production of vaccines that use adenovirus as vectors more cost-effective and contamination-free.

GSK's Shingrix has nabbed a huge chunk of the U.S. shingles-shot market, just five months after it was approved by the FDA.