‘Exciting, but Don't Overhype’: Experts Weigh In on New Cancer-Killing Drug

A new experimental drug was found to completely remove tumour in cancer patients. What do experts think of it?

What if cancer could be cured without risky surgeries, and painful procedures like chemotherapy?

A group of researchers in the US may just have found the key to doing just that.

A new study published in the New England Journal of Medicine has found that the drug, Dostarlimab – administered every three weeks for six months in patients with a subset of stage II and III rectal cancer – was able to make the tumour 'vanish' in all participants.

The findings of the study are remarkable, and open unprecedented possibilities as far as the future of cancer treatment is concerned.

But are we getting ahead of ourselves? The experts FIT spoke to say, yes.

Let's take a closer look at the study, and break down its findings.

The Drug & the Study: What Do We Know?

The phase 2 study involved 12 select participants who were administered a treatment of dostarlimab, an anti–PD-1 monoclonal antibody developed by pharmaceutical giant, GSK plc.

• All 12 participants were patients of mismatch repair-deficient stage II or III rectal adenocarcinoma.

"Rectal cancer happens in the last part of the large intestine and is seen more among the younger age group (comparatively). It is treated traditionally with chemotherapy, radiation, and surgery."

Dr Ashok Kumar Vaid, Chairman, Medical and Haemato Oncology , Cancer Institute, Medanta Hospital Gurugram

• They were all given 1 dose of the drug, 3 times a week for 6 months.

• All participants, have also undergone a follow-up at least 6 months after the treatment period, up to 25 months.

• No evidence of tumour was detected in any of the 12 patients at these points, even after different types of extensive testing.

• None of these patients received chemoradiotherapy or underwent surgery.

"The drug is a type of immunotherapy – known as an immune checkpoint inhibitor – it works through the immune system of the body," explains Dr Ashok Kumar Vaid, Chairman, Medical and HaematoOncology , Cancer Institute, Medanta Hospital Gurugram.

"We do not know if it will work for other cancers, apart from rectal cancer because testing and trials have not been done," he adds.

"(My) initial thoughts were that this was very exciting because without any radiation, surgery or chemotherapy, patients were getting cured. A deeper dive brings up questions," Dr Anil Heroor, Director-Advanced OncoSurgery Unit, Fortis Hospitals Mumbai tells FIT.

Drawbacks of the Study 

• Small sample size

For one, the study only involved 12 participants. "This was a report of 12 cases, and not a clinical trial," says Dr Ashok Kumar Vaid.

"The result of this report is very encouraging, but only once a larger study is done will the findings be validated," he adds.

Dr Anil Heroor holds a similar opinion.

"12 patients in the rectal cancer universe is not even a fraction. To give perspective, there are about 80,000 colorectal cancer patients in India alone being diagnosed with rectal cancer each year," he says.

"In the world, there are about 1.4 Million cases of rectal cancer and that was 2 years ago. To base a treatment-changing study on just 12 patients is a little too much to ask."

Dr Anil Heroor, Director-Advanced OncoSurgery Unit, Fortis Hospitals Mumbai

• Short follow up period

Dr Heroor also points out that the follow up time is not adequate to conclusively say the cancer was 'cured'.

"It is a very short follow-up. It’s about 25 months follow up at best, we’re not looking at 5 years or 10 years or a complete cure," he says.

Speaking to FIT, Dr Shubham Garg (IOSPL), Surgical Oncology, Fortis Hospital, Noida, agrees, saying, "When we say that they haven't got any disease in one year, can we claim that the disease has been cured? People who are very optimistic will say yes, they have been cured."

"But as an oncologist we keep our fingers crossed that this has to be maintained for another two-three years to say that yes, they have been cured," he goes on.

"This is how any study begins," Dr Garg adds.

"This is... a very experimental phase where they will just test this drug in a very super selected group of patients, and if it shows promise then they will plan a bigger study with a larger number of patients."

Dr Shubham Garg (IOSPL), Surgical Oncology, Fortis Hospital, Noida

Who Is Eligible for This Treatment?

The study also involved a very specific subset of rectal cancer patients – those with mismatch repair-deficient stage II or III rectal adenocarcinoma.

Explaining this, Dr Anil Heroor, Director-Advanced OncoSurgery Unit, Fortis Hospitals Mumbai, tells FIT, "There is a particular genetic abnormality in some tumours, MMR Deficiency – DNA Mismatch gene repair."

"If the MMR deficient gene is present in the tumour, only then can you expect any kind of responses because of this drug."

Dr Anil Heroor, Director-Advanced OncoSurgery Unit, Fortis Hospitals Mumbai

"This MMR deficiency forms about 5-10 percent of the entire rectal cancer universe," he adds.

"This is only a subset of cancer. This is just a group of patients. We cannot generalize. You can't say that you will no longer need the existing cancer treatments," adds Dr Shubham Garg.

How Much Will the Treatment Cost?

Even if one does qualify for the drug, chances are you still may not be able to afford it.

"From what I’m told, this drug costs 11,000 US Dollars per dose. It would require 8 doses, so 88,000 USD for a full course, which is about I crore, approx."

In a country like India, the cost of drugs and treatments can really determine the scope of its impact, he adds.

Dr Garg adds to this, saying, "The alternative to this, the traditional treatment, is one-tenth of the price of this drug. So even if this drug was available in the market right now, none of use would be able to afford it."

However, Dr Garg also adds that the price is expected to come down with time, although it will be a long way off.

Experts Speak: ‘Let’s Be Realistic’

"Is it a step in the right direction? Yes. Am I excited by the news? Scientifically, yes," says Dr Heroor.

But, at the same time, let's keep our expectations in check, say experts.

"I had a patient who had cancer of the female genitalia (Vagina) calling me up (asking) if this drug is available in India and 'will I benefit from it?' So, I think it's also raising people’s hopes too much."

Dr Anil Heroor, Director-Advanced OncoSurgery Unit, Fortis Hospitals Mumbai

Dr Garg speaks of similar cases of misplaced hope among his patients.

"Patients that come to us get misguided, saying 'I will not get surgery done, I will not get chemotherapy, I want to take such a drug'," he says.

"If I were to put it in one line, I would say this is molecular biology at its best. We, oncologists, are very happy," Dr Garg adds, reiterating, "but, let people not be misguided and think that now they don't need to undergo any treatment. So, my only request is, let's not hype it."

"We should also have the fine print in media and not just the headlines where we scream that we have a wonder drug or a miracle cure for Cancer."

Dr Anil Heroor, Director-Advanced OncoSurgery Unit, Fortis Hospitals Mumbai