First UK patient received mRNA cancer dose in October, months before reports of King Charles’ cancer

News broke that King Charles III had cancer. In next to no time, social media users started claiming it was all a ruse to promote a new mRNA cancer therapy in the United Kingdom.

"King Charles diagnosed with cancer, look at the timing of this. The first UK patients have received a mRNA cancer jab same poison used for Covid," read the text in a Feb. 8 Instagram post. "Watch them announce that King Charles has received the new mRNA cancer then announce (it’s) a success."

(Screenshot from Instagram)

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First, mRNA — also called messenger RNA — is used as a technology in vaccines. It is not a poison. mRNA vaccines use genetic code to teach cells to create proteins similar to those present in viruses, according to an explainer from Penn Medicine, where the technology was first invented. These proteins then prompt immune systems to create antibodies against those viruses. This technology was used to develop COVID-19 vaccines and is also being used to develop vaccines for diseases like herpes, HIV and cancer. 

The photo in the post appears to be a screenshot of a Feb. 5 X post. The post included images of other X posts and articles, including ones originally published by the Telegraph and the U.K. Department of Health and Social Care.

Buckingham Palace announced King Charles’ cancer diagnosis on Feb. 5. A day before, media reported that a new cancer treatment using mRNA was administered to the first U.K. patients, in a phase 1/2 clinical trial called "Mobilize." The Telegraph article shown in the X post was about the same trial.

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But the first trial participant in the U.K. received the vaccine in October 2023, months before King Charles’ cancer diagnosis was revealed. The treatment was developed by Moderna, which announced the mRNA-4359 development program in February 2022. 

U.K. Health and Social Care Secretary Victoria Atkins posted on X Feb. 4, welcoming the vaccine trial "as we mark #WorldCancerDay."

The trial seeks to test if the therapy is safe and tolerated by patients with solid tumor cancer, whether by itself or in combination with a cancer drug called pembrolizumab. Researchers are also investigating this combination’s potential in shrinking tumors. It is being conducted in several locations around the globe, including the U.S., Australia and Spain. The trial dates are from August 2022 to December 2027.

The treatment uses messenger RNA to introduce markers from tumors to the immune system, so it can recognize and defend the body against cancer cells expressing those markers. 

Dr. David Pinato, a clinician scientist at Imperial College London’s department of surgery and cancer, said the research is still in the early stages and it may take years for it to be available to patients. 

We reached out to members of the Imperial College Healthcare NHS Trust about the claim but have not heard back.

The second article shown in the X post was from a Department of Health and Social Care press release published Jan. 6, 2023, more than a year before King Charles’ cancer diagnosis was announced. The press release was about an agreement between the government and BioNTech for early access to trials on personalized mRNA therapies, such as cancer vaccines.

King Charles’ cancer diagnosis was not announced just as the first patients in the U.K. received a new mRNA cancer jab, and there’s no evidence they are linked. We rate that claim False.