Last week, Secretary Kennedy continued to spread lies on national TV claiming that “none of the vaccines on the CDC’s childhood recommended schedule was tested against an inert placebo.” Adding that: “we know very little about the actual risk profiles of these products.”
Those claims are lies.
Vaccines licensed in the US do undergo rigorous placebo-controlled clinical trials before they ever make it to the public. This includes the childhood vaccines on the CDC’s recommended schedule.
Vaccines go through three phases of clinical trials before the FDA even considers licensing them.
- Phase 1, a small group of volunteers receives the vaccine to assess safety and dosing.
- Phase 2 expands the pool to hundreds to assess both safety and immune response.
- Phase 3 involves thousands of participants and includes randomized, placebo-controlled, and blinded trials. That means some participants get the vaccine and others get a placebo, and neither they nor the researchers know who got what until the end of the trial.
- Phase 4 is ongoing safety and effectiveness monitoring in the real world.
The FDA’s Vaccine and Related Biological Products Advisory Committee (VRBPAC)—a panel of independent experts—reviews all the data before any vaccine gets the green light.
Before and after the vaccine is licensed the FDA also closely inspects the manufacturer’s processes, batch-by-batch, to ensure the vaccine is being produced according to rigorous quality standards. Samples from each lot are assessed.
Then comes CDC review. Even after FDA approval, a vaccine isn’t added to the childhood schedule until the CDC’s Advisory Committee on Immunization Practices considers key questions:
- How safe and effective is the vaccine at specific ages?
- How serious is the disease it prevents?
- What would happen if we didn’t vaccinate?
Only after these questions are carefully reviewed—and the benefit-risk ratio is clear—does a vaccine get recommended to the CDC for inclusion in the child and adult immunization schedules.
And then, to top all this off, safety monitoring continues after approval and marketing. Included in the post marketing phase are:
- VAERS (Vaccine Adverse Event Reporting System) collects early warnings of any side effects and reports findings.
- VSD (Vaccine Safety Datalink) lets CDC scientists analyze real-world vaccine data from millions of people for analysis and reporting.
- CISA (Clinical Immunization Safety Assessment) conducts targeted studies to investigate safety in specific populations.
Updates to already licensed and approved vaccines like the annual influenza and COVID vaccines are sometimes evaluated against older versions instead of inert placebos. There are several reasons for this. When an effective vaccine already exists, it’s considered unethical to withhold protection by using an inert placebo in trials each year. Influenza vaccines also produce hemagglutination-inhibition antibody titers which lets researchers and regulators to approve strain updates based on immunogenicity data alone. Also, the annual flu vaccine update needs to be manufactured and distributed months ahead of winter—waiting for full Phase 3 trial data for each new strain would be impossible. Since full trials aren’t repeated annually for influenza, regulators rely on robust post-market monitoring systems to ensure safety through the VAERS, VSD, and CISA systems continuously track safety signals after rollout. They also examine real-world evidence (e.g., hospitalization reductions, side‑effect trends) to assess both safety and efficacy.
Bottom line: Vaccines are among the most rigorously tested and monitored medical products we have. For Secretary Kennedy to keep lying about this is unethical, irresponsible and dangerous. Honestly, it’s quite shocking for an HHS Secretary to continue to spout blatantly false things like this.
And for journalists: platforming Kennedy without correcting or challenging these statements is a failure of responsibility to the public.
Vaccines save lives. The science is clear. The testing is real. And the public deserves better than a steady stream of misinformation and blatant lies from Kennedy.
