Dr. Sajan Rajpurohit, Director – Medical Oncology, BLK Max Super Specialty Hospital
This trial was conducted in twelve patients and they published the data, the results of which are now known internationally. This medicine is actually useful in a subgroup of patients with rectal cancer who have a specific genetic abnormality known as MMR, which is known as a mismatch repair gene deficiency. Therefore these patients respond very well to this monoclonal antibody. It is a type of antibody, which works by improving the body’s immunity, and it helps the body’s own immunity to kill and kill cancer cells. The results are indeed very fascinating as all 12 patients had a very good response, and at six months, no tumors were seen in their bodies. So the results are very encouraging. How I view this outcome, although this is a phase two data that we have, it looks like a very effective treatment for this subset of patients. And of all cancer patients, 5% will be those who have this type of deficiency in cancer cells. So such drugs can work wonders in this type of tumor.
So with respect to cancer treatment, cancer is very curable, especially in the first stage, sometimes even in stage three. Only stage four is where we really struggle to find a cure. But then with these new antibodies that are targeting specific gene abnormalities in cancer cells, we are reaching the clarinet of a functional cure, even in stage four cancer patients.
Dr. Wesley M. Jose, Clinical Associate Professor, Medical Oncology, Amrita Hospital, KochiThis is an important test to prove the concept of tailoring cancer treatments to individual patients. However, this trial drug (Dostarlimab) is not a panacea for all cancers. Dostarlimab is an immunotherapy drug. Immunotherapy drugs have become another pillar of cancer care in recent years. Many drugs similar to dostarlimab (pembrolizumab, nivolumab, atezolizumab, ipilimumab etc.) are now on the market including the Indian market and will be available at a cancer center near you. But all these drugs are for very specific indications.
The 12 patient trial is a very small trial (called a phase 2 trial) and has been done in patients with cancer of the rectum (the terminal part of the large intestine). All these patients were unique because their cancer lacked a gene called mismatch repair. People with this type of gene abnormality are more sensitive to treatment with immunotherapy. That is why there is such a response to the treatment. The reason there are no side effects is because the case count is very low and the duration of treatment is relatively short. Dostarlimab may be a very important drug in the oncologist’s arsenal, but it is unlikely to be a magic bullet.
The major concern at present is the cost of immunotherapy drugs. A paper presented by Tata Memorial Hospital at the same meeting where the dostarlimumab data was presented pointed out that only three percent of Indian patients are able to afford these drugs, which is a regrettable situation. We need not only medicines but also policies that make these medicines affordable and available to the common people. This is a tall order.
This is the hope of every oncologist and every cancer researcher as far as the earliest cure is found. Only time will tell…
Dr. Sachin Almail, Section Coordinator of Medical Oncology, PD Hinduja Hospital and Medical Research Centre, Mumbai
It was used for rectal cancer with 12 patients, so it’s too early to say that it may be pioneering but it’s definitely something as these results have never been seen in clinical trials. It is quite interesting to see how these immuno checkpoint inhibitors worked and 12 patients were found to be cancer free.
We need to be careful about this trial, there was a small group of people who worked in it, plus a very small percentage of patients with rectal cancer would be suitable for this treatment. But it is certainly a start towards more effective cancer care.
Dr. Shishir Shetty, Senior Consultant – Surgical Oncology, Apollo Cancer Centre, Mumbai
The news of dostarlimab, a new hope, a revolution in cancer treatment that was presented at ASCO, has been making my phone ring for the past few days. The study has been tested on very few patients which is 12. I believe a larger study is needed to proceed with clinical implementation. The estimated treatment cost would be above 1.5 crores.
Only a select few cancer types with a specific biology (MMR deficiency) would be eligible (about 5% of all tumors, not all). There is no doubt that this is a revolution in cancer treatment and is going to pave the way for more research and discovery of cancer cures without any chemotherapy/radiation or surgery.
However, I believe that the treatment should be thoroughly tested in terms of time and application for strong reliability. By far, surgery is the simplest, cheapest, and most effective treatment for solid tumors.