On May 1, The New York Times reported that Health Secretary Robert F. Kennedy Jr. announced plans to require all new vaccines to be tested against placebos. A spokesman for the Department of Health and Human Services described this requirement as “a radical departure” from existing standards. However, it was noted that the impact would depend on how “new” is defined since most new vaccines are already tested either against placebos or other disease vaccines.
John D. Gräbenstein, RPh, PhD, a pharmacist with expertise in vaccinology since 1983, provided insights into vaccine testing practices in the United States. Dr. Gräbenstein explained that before any vaccine can be widely used, its safety and efficacy must be established through phase 1, phase 2, and phase 3 studies. For the past 75 years, testing vaccines against comparison products in phase 3 studies has been standard practice both in the U.S. and globally.
Dr. Gräbenstein highlighted that randomized, double-blinded, placebo-controlled studies are considered scientifically convincing for evaluating vaccine outcomes compared to unvaccinated groups.
He elaborated on what constitutes a placebo: options include saline solutions or liquids differing only in antigenic content from the vaccine being tested.
Vaccine studies without a placebo control arm can still be robust if they use an alternate vaccine or an earlier version of the same vaccine as a comparator to ensure ethical study conditions.
The FDA and vaccine developers decide together on control interventions for pre-licensure trials based on known information and ethical considerations.
Sharon G. Humiston contributed references for further reading on placebo use and controls in vaccine testing prior to licensing.
