By Daniel Wu
November 14, 2024 at 6:00 a.m. EST
When Beata Halassy learned in summer 2020 that her breast cancer had come back, she made a bold decision. As a virologist at the University of Zagreb in Croatia, she knew that researchers around the world were testing virus-based cancer treatments that could avoid the destructive side effects of conventional treatments like chemotherapy.

Halassy, who studies viruses for a living, decided to test some of them on herself.

With her oncologists’ approval, she made herself a test subject and worked with colleagues to inject herself with two types of viruses that she cultivated in a lab, the science journal Nature reported. Over several weeks, her homegrown remedy caused her tumor to shrink, enabling surgeons to remove it.

In a study documenting her experiment, published August in the peer-reviewed journal “Vaccines,” Halassy and her co-authors said that the “unconventional” treatment has left her in remission for almost four years.

Bioethicists told The Washington Post they were split on Halassy’s decision to enter the storied, controversial tradition of self-experimentation in medicine and publish her results. While Halassy was uniquely qualified to weigh the decision and carry out her tests on herself, she still may have lacked the perspective of an objective researcher as her own test subject, they said. And her study of just one patient isn’t likely to provide enough information to draw conclusions about the treatments she tested.

“From my perspective, self experimentation is not fundamentally unethical,” said Alta Charo, a professor emerita of law and bioethics at the University of Wisconsin at Madison. “It may be unwise. It may indeed be tainted by an unrealistic set of expectations. … But I don’t see it as fundamentally unethical.”

Halassy and two of her co-authors did not respond to requests for comment, but Nature identified her as the researcher who was her own test subject. Halassy’s study describes the person treated as “a 50-year-old self-experimenting female virologist,” and she is the only person on the author list who meets that description.

Studies exploring the use of viruses to treat cancer date back over a decade. The Food and Drug Administration first approved a form of oncolytic virus therapy, the use of viruses modified to specifically attack cancer cells, to treat skin cancer in 2015. Research since then has sought to widen the range of cancers that OVT can be applied to. But clinical trials for novel treatments like OVT are sometimes limited, Halassy and her co-authors wrote in their study, by being carried out first on patients whose health may have already been affected by conventional treatments like chemotherapy or radiotherapy.

Halassy was in a different situation. She was several years removed from her breast-cancer diagnosis in 2016 and her subsequent chemotherapy. And she was a rare subject who had the means and the know-how to produce and administer her own experimental viral treatment.

Halassy and her colleagues used two types of viruses — a strain of measles used in vaccines, and vesicular stomatitis virus, which affects livestock — that she prepared in her own lab, according to the study. The viruses were injected directly into the tumor at various intervals over about six weeks.

Advertisement Around 11 days into the regimen, Halassy’s tumor began to shrink and continued to diminish gradually until it was small enough to be surgically excised after the six weeks of injections ended. It was a sterling result, the study states — the treatment came with few serious side effects, save for a day when Halassy developed a fever, and enabled surgeons to remove the tumor without further growth or spread in her body.

Halassy’s breast cancer had returned twice after her 2016 diagnosis. After the viral treatment, she has been cancer-free for 45 months, the study says.

With the experiment, Halassy joins a long line of researchers who have tested medical theories on themselves. Their attempts have led to significant medical breakthroughs — and in some cases, harm or death. Jesse Lazear, an American physician studying yellow fever in the 19th century, died of the disease after allowing himself to be bitten by a mosquito to prove how it was transmitted. Peruvian medical student Daniel Carrión died in 1885 after infecting himself with Carrión’s disease, which was later named after him.

Halassy’s self-experimentation didn’t appear to be nearly as risky as those fatal examples, said Hank Greely, the director of Stanford University’s Center for Law and the Biosciences. But he said critics might still question if a researcher in Halassy’s position could give informed consent to be a test subject and evaluate the potential benefits and harms of an experiment without bias.

“In general, it is viewed as a bad idea for physicians to take care of their patients or themselves, because they lack the objectivity necessary to do a good job,” Greely said. “The same thing holds for self-experimentation.”

Halassy and her co-authors wrote that the study did not undergo a review by an ethics committee because it involved self-experimentation, and that the subject was “fully aware of her illness as well as of available therapies” and “wanted to try an innovative approach in a scientifically sound way.”

Opponents of the practice also argue that publicizing cases like Halassy’s risks encouraging less qualified patients to self-experiment in more dangerous ways, said Greely and Charo, the bioethics professor. They added that Halassy’s study of her response to OVT was likely too limited in scope to contribute reliably to research on the treatment.

“Not every experiment is research,” Charo said.

Halassy and her co-authors acknowledged in the study that it was “isolated” but said it should encourage clinical trials to assess the efficacy of OVT in early stages of cancer. They also said the circumstances of Halassy’s study would be very difficult to repeat.

“The study was feasible only due to the unique situation in which the patient was also an expert virologist,” the study states.