The existing COVID-19 vaccine trials have included some people over the age of 65. Although final conclusions cannot be drawn at this time, Dr. Barouch noted that information from initial trials has shown the antibody response in older adults appears similar to that of younger adults, suggesting equal vaccine efficacy.
Vaccine Timeline
Throughout the talk, Dr. Barouch emphasized the need to proceed swiftly with vaccine development, and production must not lead to cutting corners. “We simply cannot compromise patient safety or regulatory integrity of the vaccine, because ultimately a vaccine has to be safe and effective, but it has to be trusted by the public to achieve its goal of widespread use,” he said.
Interim results from the Pfizer trial were released on Nov. 9. These showed no concerning safety signals, with 90% efficacy.5 The results from the Moderna trial are also expected soon, with results from other phase 3 trials to follow. Only then can we begin to compare the potential vaccine candidates in terms of safety, efficacy and other characteristics. Hopefully, these results will yield multiple workable vaccines.
However, it’s impossible to precisely predict when these might be available. “It’s not even clear when the phase 3 trials will end, let alone how quickly a vaccine can be manufactured and distributed,” said Dr. Barouch.
However, Dr. Barouch notes that one or more vaccines might be available under emergency use authorization for certain segments of the population sometime this winter. “In the best case scenario, there could be a roll out of vaccines to the more general population in the spring or summer, but that would really require everything to work perfectly from this point forward,” Dr. Barouch concluded.
Ruth Jessen Hickman, MD, is a graduate of the Indiana University School of Medicine. She is a freelance medical and science writer living in Bloomington, Ind.
References
- Chandrashekar A, Liu J, Martinot AJ, et al. SARS-CoV-2 infection protects against rechallenge in rhesus macaques. Science. 2020 Aug 14;369(6505):812–817.
- Yu J, Tostanoski LH, Peter L, et al. DNA vaccine protection against SARS-CoV-2 in rhesus macaques. Science. 2020 Aug 14;369(6505):806–811.
- Mercado NB, Zahn R, Wegmann F, et al. Single-shot Ad26 vaccine protects against SARS-CoV-2 in rhesus macaques. Nature. 2020 Oct;586(7830):583–588.
- Luo F, Liao FL, Wang H, et al. Evaluation of antibody-dependent enhancement of SARS-CoV infection in rhesus macaques immunized with an inactivated SARS-CoV vaccine. Virol Sin. 2018 Apr;33(2):201–204.
- Pfizer Inc. News release: Pfizer and BioNTech announce vaccine candidate against COVID-19 achieved success in first interim analysis from phase 3 study. Business Wire. 2020 Nov 9.
