In a small study, US scientists succeeded in making cancer completely disappear in all participants. They used the drug dostarlimab for this. We explain what it’s all about.

“There were many tears of joy.” With these words, oncologist Andrea Cercek describes the study results in the “New York Times”, which she has now published together with other US scientists: The team at the New York Memorial Sloan Kettering Cancer Center had the help of a specific drug made all cancer cells disappear in twelve patients.

The patients all suffered from rectal cancer and would have had to endure other treatments such as chemotherapy, radiation and surgery without the drug. The latter could lead to intestinal, urinary and sexual dysfunction. But the treatment with the new drug was enough to make the cancer cells in their bodies finally disappear.

“I believe this is the first time in the history of cancer,” said co-author Luis A. Diaz of the data, which was published in the New England Journal of Medicine.

The drug is dostarlimab, a monoclonal antibody. As the “gesundheitverständig.de” portal from the Institute for Quality and Efficiency in Health Care (IQWiG) writes, it is already approved in Germany for the treatment of women with uterine cancer who are not affected by chemotherapy. It is administered as a drug in Germany under the trade name “Jemperli”.

Dostarlimab is said to “inhibit certain cancer cells and thus stop the cancer,” explains the IQWiG portal. As the study authors explain in the New York Times, the drug is able to unmask cancer cells and help the immune system to identify and destroy them.

So far, the antibody agent has been used for cervical cancer, for example, when the so-called “mismatch repair” no longer works in the affected body region. Among other things, this is responsible for correcting errors in the gene mutation.

If this no longer works, “mutations accumulate in the tumor tissue,” writes the IQWiG portal. These mutations occur in an average of four percent of all cancer patients. According to “krebs-praedisposition.de”, the mutated genes then increase the risk of cancer.

According to the researchers, dostarlimab usually causes side effects in around a fifth of those treated. Three to five percent even suffer serious consequences. According to the “Pharmazeutische Zeitung”, these include, for example

Surprisingly, however, the study participants did not exhibit any of these serious side effects. According to experts with whom the New York Times spoke, the lack of side effects could also be due to the fact that the number of participants was very small – or that the drug behaves differently in this type of cancer.

According to the medics, it is the first time that a study has “completely eradicated” the cancer in every patient. However, that does not mean that the patients have now finally been cured. The study was “small but compelling,” wrote Hanna K. Sanoff of the University of North Carolina’s Lineberger Comprehensive Cancer Center in an editorial. But “very little is known about the time it takes to find out whether a complete clinical response to dostarlimab is equivalent to a cure.”

The patients were examined between six and 25 months after treatment. According to experts, the so-called “five-year survival rate” applies to technically speaking of a cure. This means that only those who are cancer-free five years after the initial diagnosis are considered cured.

The study results could be relevant for future treatments. However, this requires further research work. The number of participants was very small. Kimmie Ng, a colorectal cancer expert at Harvard Medical School, told The New York Times that while the results were “remarkable” and “unprecedented,” they needed to be replicated first.