The New Placebo Mandate for Vaccines: Unethical, Unscientific, and Impossible

Would You Test Seatbelts by Telling Half the Children to Ride Unprotected?

This week, HHS Secretary Robert F. Kennedy Jr. announced plans to require all new vaccines to undergo placebo-controlled trials before approval. According to The Washington Post, an HHS spokesperson stated that "all new vaccines will undergo safety testing in placebo-controlled trials prior to licensure — a radical departure from past practices."

Kennedy also emphasized a commitment to “radical transparency.”

As public health experts, we're deeply concerned about this development. The HHS statement claims that "except for the COVID vaccine, none of the vaccines on the CDC's childhood recommended schedule were tested against an inert placebo". (An inert placebo is a “fake” treatment that looks and feels like the real thing, but it doesn’t contain any active ingredients or have any direct effect on the body.) This fundamentally misrepresents the scientific record and ignores decades of robust vaccine research and safety monitoring. Let’s discuss…

unbiasedscipod

A post shared by @unbiasedscipod

The Buzzword Problem: When "Double-Blind Placebo-Controlled" Becomes a Weapon Against Public Health

Every time we post about vaccines, we're inevitably met with the same demand: "Where are the double-blind placebo-controlled trials?" This phrase has become a buzzword, wielded without understanding the scientific and ethical nuances involved.

We hear you. This demand seems reasonable at first glance – after all, randomized controlled trials are often called the "gold standard" in medical research. But this simplified view ignores basic principles of research ethics and the cumulative nature of scientific knowledge.

Let's be clear: "placebo-controlled" isn't a one-size-fits-all requirement for rigorous science.

Would we demand that newer, safer versions of car seats be tested by randomly assigning half of the toddlers in a study to go without them?

Or trial a new design of bike helmet by insisting that half the cyclists wear no helmet at all?

Or trial a new baby formula tested against water (the inert placebo) to see which babies grow and develop better?

Of course not –it is profoundly unethical when the evidence for the intervention is overwhelming. You don’t need a placebo when the benefit is already proven, and withholding it would hurt people.

The same principle applies to vaccines with established safety and efficacy profiles.

Threads post by Dr. David Higgins (@drhigginsmd)

Why Withholding Vaccines in Studies Raises Serious Ethical Concerns

The core issue here is bioethics – the moral principles that govern medical research involving human subjects.

Let's be blunt: A study that deliberately withholds proven vaccines from children would never pass review by an Institutional Review Board (IRB) – the independent committees legally required to review and oversee research to ensure ethical standards are met and that participants are protected, which is required by law in the U.S. for any study involving human subjects.

Here's why:

1. The principle of equipoise (genuine uncertainty about which treatment is better): Ethical research requires genuine uncertainty about which intervention is superior. Once we have clear evidence that vaccines prevent serious diseases, we can no longer ethically randomize children to receive placebo and remain unprotected and at risk. In some instances clinical trials can be interrupted mid-trial because once the data shows that the intervention is so effective, to continue to give some participants the placebo is now considered unethical.

2. Minimal risk standard: Research involving children must pose no more than minimal risk without the prospect of direct benefit. Leaving children unvaccinated against diseases like measles or polio clearly exceeds this threshold.

3. Risk-benefit ratio: The potential risks of withholding vaccination from children in a control group far outweigh any additional scientific knowledge that might be gained.

4. Human subjects protections: Federal regulations established following historical research abuses explicitly protect vulnerable populations, including children. A study deliberately leaving children susceptible to preventable diseases with known serious consequences would be rejected by any reputable IRB.

niniandthebrain

A post shared by @niniandthebrain

We cannot envision how a research protocol that intentionally withholds proven vaccines from children could possibly receive IRB approval or satisfy human subjects protection requirements. Such a study would violate core principles that have guided ethical research for decades.

Imagine explaining to parents: "We're going to randomly decide whether your child gets protected against measles – a disease that can cause brain inflammation and death – or gets nothing, just so we can prove again what we already know." The obvious ethical issues become immediately apparent.

Medical ethics is not an abstract concept – it's about real children and real lives. When we know that vaccines prevent death and disability, deliberately withholding them crosses a profound ethical line.

sciencewhizliz

A post shared by @sciencewhizliz

Different Types of Controls: Science Adapts to Ethical Realities

As scientists, we don't just throw up our hands when placebo controls aren't ethical. We adapt our methods:

• Inert Placebos: We use saline (salt water) placebos for completely new vaccine types. “Inert” here means it doesn’t produce an immune response or have any biological effect. The first mRNA COVID vaccines underwent precisely this kind of testing because the technology was novel.

• Active Placebos: Sometimes we use placebos containing everything except the antigen (the part that generates immunity). This helps isolate whether side effects come from the antigen or other ingredients.

• Comparator Vaccines: For diseases where effective vaccines already exist, we often compare new vaccines against established ones. This approach is not just scientifically sound—it's mandated by research ethics.

These different methods to evaluate vaccines don’t lower standards—they raise them by incorporating ethical considerations alongside scientific rigor. Our approach balances our obligation to generate reliable safety data with our responsibility to protect research participants.

Note: While generally unethical in the U.S. and other high-income countries, a WHO expert panel has identified specific, limited circumstances where placebo-controlled vaccine trials might be justified internationally, primarily in settings where an effective vaccine isn't locally available or appropriate. These special cases include developing locally affordable vaccines or evaluating local efficacy in significantly different populations - situations that don't apply to the current U.S. context.

The Real Evidence: How Vaccines Actually ARE Tested

Let's address the myth head-on: Vaccines on the childhood schedule HAVE undergone rigorous testing. Here are the facts:

• Salk Polio Vaccine (1954): One of the largest clinical trials in history included 623,972 children who received either the vaccine or inert (saline) placebo. The results were dramatic: 80-90% effectiveness against paralytic polio with no unexpected side effects.

• Measles Vaccine (1960s): Early trials compared different vaccine formulations against inert (saline) placebo, showing powerful protection against a disease that once infected virtually every child and killed thousands annually.

• Rotavirus Vaccines: Modern trials like the 2009 Rotavirus Efficacy and Safety Trial (REST) included nearly 70,000 infants with inert placebo controls.

• COVID-19 Vaccines: Both Pfizer and Moderna mRNA COVID-19 vaccines underwent full inert (saline) placebo-controlled Phase 3 trials with tens of thousands of participants.

For newer iterations of established vaccines, we don't start from scratch – we build on decades of safety data. This isn't cutting corners; it's responsible science that preserves both rigor and ethics.

Beyond premarket clinical trials, we continue to monitor vaccine safety through post-licensure (Phase 4) trials and multiple robust surveillance systems. The Vaccine Adverse Event Reporting System (VAERS), Vaccine Safety Datalink, systems in the Veterans Affairs (VA ADERS) and Department of Defense (VAECS), among others, continuously track data from millions of doses, capable of detecting even extremely rare side effects. In Canada, these are tracked by the Canadian Adverse Events Following Immunization Surveillance System (CAEFISS), and in the UK by the Medicines and Healthcare Products Regulatory Advisory.

In addition, the U.S. draws on multiple national, regional, and global vaccine safety surveillance systems to monitor and inform vaccine safety domestically. Vaccines are among the most extensively studied medical interventions when it comes to safety.

The Real-World Impact: Historical Evidence That Cannot Be Ignored

Sometimes the most powerful evidence isn't from controlled trials but from population-level data showing dramatic before-and-after effects:

• Measles: From 3-4 million cases and 500 deaths annually in the U.S. to fewer than 100 cases in most years.

• Polio: From 15,000 paralytic cases annually to zero cases of wild polio (the original type of polio virus found in the environment, not derived from vaccines) in the U.S. since 1979.

• Diphtheria: From 200,000 cases and 15,000 deaths annually to fewer than 5 cases per year.

Are we willing to possibly let children die to satisfy demands for a study design that is not necessary?

What Does RFK Jr.'s Proposal Really Mean?

kmpanthagani

A post shared by @kmpanthagani

As experienced public health researchers, we see several alarming implications in this proposal:

1. Ethical regression: This approach asks us to ignore the bioethical guidelines that protect research participants from unnecessary harm.

2. Delayed lifesaving interventions: Adding unnecessary testing requirements would extend development timelines for vaccines that build on established platforms – meaning more preventable deaths and disabilities in the interim.

3. Scientific misrepresentation: The claim that vaccines haven't been properly tested fundamentally misrepresents decades of rigorous research and ongoing safety monitoring.

4. Undermining vaccine confidence: As Paul Offit, director of the Vaccine Education Center at Children's Hospital of Philadelphia, told The Washington Post: "You are watching the gradual dissolution of the vaccine infrastructure in this country. The goal is to make vaccines less available and less affordable."

The administration has already begun scrutinizing coronavirus vaccines, with FDA Commissioner Marty Makary suggesting there's "a void of data" – despite the fact that COVID-19 vaccines underwent some of the largest and most transparent clinical trials in history.

A Better Path Forward

We support rigorous vaccine safety standards. We believe in transparency and continuous monitoring. And we understand that science must be ethical, and that knowledge is cumulative.

The current approach to vaccine safety isn't broken – it represents decades of careful refinement that balances scientific rigor with ethical responsibility:

• Rigorous trials that use appropriate controls based on existing evidence

• Extensive pre-licensure safety testing

• Multiple post-approval surveillance systems

• Ongoing studies across diverse populations

When people ask, "Where are the placebo-controlled trials?" we need to reframe the question: "How can we ensure vaccine safety while respecting ethical principles and protecting vulnerable populations?"

The answer isn't to turn back the clock on research ethics. It's to embrace the comprehensive, ethically sound approaches we've developed – ones that have made vaccines among the most thoroughly tested and monitored medical interventions in history.

Stay Curious,

Unbiased Science

P.S. Want to support our work? The best way is to subscribe to our Substack and share our content. While all our articles are always completely free to read, paid subscriptions help sustain our in-depth reporting on public health and science topics. Thank you for considering it!