Doctor Who Provided New Cancer Drug Explains Why She Thinks It Worked

The patients were treated with an immunotherapy drug called dostarlimab, and following the trial the doctors found the rectal cancer had vanished in all 18 patients, so much so that it could not be detected by physical exam, endoscopy, PET scans or MRI scans.

"We'd certainly never seen this before, it's really what cancer doctors' dreams are made of," she continued.

Dr. Cercek explained dostarlimab works by 'unlocking the body's natural immune system to fight cancer', and said this particular treatment works in 'specific cancer cells' which lack a gene which enables them to repair their DNA, ultimately leading to mutations.

She said: "When we give immunotherapy like dostarlimab it really just revs up the immune system so that it sees the cancer and gets rid of it. But what's so remarkable here is that it completely eliminated the cancer, the tumours just vanished."

The doctor went on to explain that such results are typically only visible in 10 percent of patients with advanced cancer, making the study's results even more 'striking'.

The inspiration for the study came from a clinical trial led by Dr. Diaz in 2017, which involved 86 people diagnosed with metastatic cancer which shared a gene mutation that prevented cells from repairing damage to DNA.

Patients from the earlier trial took a checkpoint inhibitor for up to two years, after which results revealed tumours shrank or stabilised in about one third to half of the patients and disappeared altogether in 10 percent of the participants.

The results led Dr. Cercek and Dr. Diaz to question what would happen if the drug were administered earlier in the course of the disease, resulting in the more recent successful trial.