The coronavirus vaccine developed by the University of Oxford and the drugmaker AstraZeneca (AZN  ) was found to trigger a similar immune response across all adult age groups, according to preliminary data published in The Lancet on Thursday.

The vaccine's Phase II trial consisted of 560 healthy adult volunteers--160 aged 18-55, 160 aged 56-69, and 270 aged 70 and above--receiving either two doses of the vaccine or two shots of an inert placebo 28 days apart. Preliminary data analysis found that that potential vaccine produces a similar immune system response across all adult age groups, with no serious side effects.

The study is slightly different from those conducted by other coronavirus vaccine frontrunners, for researchers focused on testing the immune responses of older adults, which is a group that has been found to be significantly more vulnerable to severe SARS-CoV- 2 infection. Older adults also experience decreased immune function and are at risk of having underlying health conditions, so an effective vaccine is for this age group is extremely important.

The vaccine's developers are currently conducting a Phase III, or late-stage, clinical trial of the drug to test whether or not the vaccine is safe and effective at preventing coronavirus infections in a diverse group of volunteers, including participants with underlying health conditions.

Oxford Vaccine Groups'd Director Dr. Andrew Pollard told reporters on Thursday that it is still too early in the study's research to tell whether or not the vaccine to protect against the virus.

"We're still waiting to get to the point where we can do the analysis to just work out how well the vaccine can protect people, and we're getting ever closer to that," Pollard told reporters, quoted by Reuters. "We are optimistic that we'll be able to do that before Christmas, and obviously we'll share that with you as soon as we can at that point."

The Oxford/AstraZeneca vaccine's technology differs from other frontrunners like Pfizer (PFE  )/BioNTech (BNTX  ) and Moderna (MRNA  ), for the vaccine uses a modified version of the a virus similar to the common cold instead of a manufactured messenger RNA.

Remdesivir Update

The World Health Organization (W.H.O.) on Thursday advised global health care workers against using Gilead Sciences's (GILD  ) antiviral drug remdesivir--commercially named Veklury--as a treatment for patients hospitalized for their coronavirus infection. The global health agency's Guideline Development Group stated that there is currently "no evidence" that supports the use of the drug to improve survival rates or shorten infection recovery time.

The G.D.G. "concluded that remdesivir has no meaningful effect on mortality or on other important outcomes for patients, such as the need for mechanical ventilation or time to clinical improvement, the W.H.O. announced in a published review in the journal The BMJ. The new recommendation is based on the W.H.O.'s SOLIDARITY trial, which compared the effects of several potential coronavirus treatments from four randomized trials that involved over 7,000 hospitalized patients.

Yet, the W.H.O.'s findings contradict other global health experts, most notably the U.S. Food and Drug Administration (F.D.A.); remdesivir is the only F.D.A. approved drug for the treatment of hospitalized coronavirus patients over the age of 12.

Gilead issued in a statement that remdesivir "is recognized as a standard of care for the treatment of hospitalized patients with Covid-19 in guidelines from numerous credible national organizing, including the U.S. National Institutes of Health and Infectious Diseases Society of America, Japan, U.K., and Germany. These recommendations are based on the robust evidence from multiple randomized, controlled studies published in peer-reviewed journals...We are disappointed that W.H.O. guidelines appear to ignore this evidence."