Findings About Dostarlimab, A New Antibody Drug, Very Encouraging, Says Expert In Cancer Treatment

“This new trial at MSKCC in a small number of patients, with locally advanced rectal cancer patients who had MMR (MisMatch repair) deficiency, have shown total disappearance of tumour without any additional treatment in all 100 percent of them. This is very encouraging but we must note that long term studies are required to understand the real impact,” Dr. (Col.) R. Ranga Rao, Chairman, Oncology, of Paras Hospitals in Gurugram said.

“The drug is still investigational and the trial is limited to patients of a specific type , that constitute about 4 to 5 per cent of rectal cancers. While this is highly encouraging, we must not prematurely jump to conclusions that we have found a cure for all cancers, all stages, and no chemotherapy, surgery is ever required,” he added.

He said it is well recognized that Immunotherapy with PDL 1 blockers in MMRd patients is effective. “Already immunotherapy has made a big difference in the field of cancer of all types. Several earlier trials have shown encouraging responses,” Dr Rao said.

In what appears to be a miracle and ‘first time in history’, a small clinical trial has found that every single rectal cancer patient who received an experimental treatment found that their cancer had vanished.

According to New York Times, in the small clinical trial conducted by Memorial Sloan Kettering Cancer Center, 18 patients took a drug called Dostarlimab for around six months, and in the end, every one of them saw their tumours disappear. Dr Luis A. Diaz J. of New York’s Memorial Sloan Kettering Cancer Center (MSKCC) said this was “the first time this has happened in the history of cancer”.

According to experts, Dostarlimab is a drug with laboratory-produced molecules and it acts as substitute antibodies in the human body. The cancer is undetectable by physical exam; endoscopy; positron emission tomography or PET scans or MRI scans, added Experts. This proves that Dostarlimab can be a ‘potential’ cure for one of the most deadly common cancers.

According to New York Times, patients involved in the clinical trial earlier underwent treatments such as chemotherapy, radiation, and invasive surgery that could result in bowel, urinary, and even sexual dysfunction. The 18 patients went into the trial expecting to have to go through these procedures as the next step. However, to their surprise, no further treatment was needed.

The findings of this trial have shocked experts and they have pointed out that complete remission in every single patient is “unheard-of”. Dr Alan P. Venook, who is a colorectal cancer specialist at the University of California, said that the complete remission in every single patient is “unheard-of”. He hailed the research as a “world-first”. Experts stated that the research was impressive as not all of the patients suffered significant complications from the drug trial.

Critics:

Tesaro, a biotech company based out of Massachusetts developed the drug. Tesaro was acquired by GlaxoSmithKline in 2019, dostarlimab is also known by the brand name Jemparli. Dostarlimab was developed to treat women with recurrent or advanced endometrial cancer.

On August 17, 2021, the FDA approved dostarlimab-gxly (brand name Jemperli) for adult patients with mismatch repair-deficient recurrent or advanced solid tumours, as determined by an FDA-approved test, that have progressed on or following prior treatment and who have no satisfactory alternative treatment options.

Rectal cancer remission

According to reports, 18 patients in the clinical trial took Dostarlimab for around six months and after over 12 months the doctors found that their cancer disappeared. While it’s a small trial so far, the results have been impressive; they were published in The New England Journal of Medicine and featured at the nation’s largest gathering of clinical oncologists in June 2022.

In every case, rectal cancer disappeared after immunotherapy — without the need for the standard treatments of radiation, surgery, or chemotherapy — and cancer has not returned in any of the patients, who have been cancer-free for up to two years.

It’s incredibly rewarding to get these happy tears and happy emails from the patients in this study who finish treatment and realise, ‘Oh my God, I get to keep all my normal body functions that I feared I might lose to radiation or surgery,’ expressed Dr Andrea Cercek, Medical Oncologist, Memorial Sloan Kettering Cancer Center (MSK).

Dr Cercek added, “The most exciting part of this is that every single one of our patients has only needed immunotherapy. We haven’t radiated anybody, and we haven’t put anybody through surgery.” She continued, “They have preserved normal bowel function, bladder function, sexual function, fertility. Women have their uterus and ovaries. It’s remarkable.”

This clinical trial could pave the way for treating other forms of cancer in the future. As the trial continues at MSK, Dr Luis Alberto Diaz, Medical Oncologist, Memorial Sloan Kettering Cancer Center (MSK) said, “It’s the tip of the iceberg.” He explains, “We are investigating if this same method may help other cancers where the treatments are often life-altering and tumours can be MMRd. We are currently enrolling patients with gastric (stomach), prostate, and pancreatic cancers.”

Dostarlimab clinical trial reception by the Indian medical community

Since the trial results have been published, it has created a lot of buzz and has got the entire medical community discussing how it could pave the path for future treatment for various cancers, ETHealthWorld spoke to few experts on the drug trial. Commenting on the trial, “It is definitely a big step towards efficient cancer care. The preliminary data on Dostarlimab PD1 monotherapy has been very encouraging in high-risk rectal cancer patients and has been recently presented at the ASCO meeting in Chicago and subsequently published in NEJM.

We would definitely need further studies on larger groups of patients across the globe to establish it as a standard of care for rectal cancer. Trials are also being conducted to study its effectiveness for cervical cancer, and endometrial cancer amongst others,” said Dr Pankaj Kumar Panda, Senior Research Officer, Apollo Proton Cancer Centre.