Metronomic Chemotherapy has shown significant advantages for the quality of life of the cancer patients: Dr. Robert Kerbel

Affordability is a big issue everywhere particularly in low and middle income countries. The cost of the new cancer drugs when they get approved and make at the market is rather alarming.

Dr. Robert Kerbel, Prof. Depts of Medical Biophysics & Lab. Medicine, University of Toronto, Canada, talks to ETHealthworld about the advancements in cancer treatment through metronomic chemotherapy.

1. When and how did you get interested and involved in Metronomics?

I got interested in the idea in retrospect of what is called metronomic chemotherapy around 1990 and the reason is that I became intrigued by the possibility that conventional chemotherapy drugs that are used to treat cancer patients may be able to work in some cases not by directly killing cancer cells but rather by killing the support network meaning the vascular blood supply that tumours need in order to grow and survive.

The idea is that chemotherapy is normally designed to target and kill the dividing cells in the body particularly in cancer where there are alot of dividing cells. Chemotherapy might have an anti-angiogenic side effect that would be good and would help control tumour growth. It was some years later that this idea was taken up by doctor Folkman who came up with a strategy to maximize and optimize the vascular targeting effects of chemotherapy.

2. Where is Metronomics placed in the global map?

Metronomics today is still very much a niche concept and is not yet widely accepted. There are no approved metronomic chemotherapy protocols. It is being adopted in some centres based on some recent randomised phase three clinical trial results. It is surely moving forward but slowly.

I would have to acknowledge and say that at the present time it is still an investigational therapy and it is still being evaluated in various clinical trials around the world and in India especially in Mumbai.

3. How suitable is it for India, where affordability is the biggest barrier?

Affordability is a big issue everywhere particularly in low and middle income countries. The cost of the new cancer drugs when they get approved and make at the market is rather alarming. A number of these drugs nowadays normally cost 5000 dollars per month of treatment and some of them cost 10-15000 dollars.

The incidence of cancer increasing is because of the ageing population and you put that together with the cost of these new drugs. The cost is just unsustainable and we have to find ways of reducing the cost of cancer drug development and the cost of cancer care and treatment.

One way of doing this would be to use older off pattern drugs, especially if they are safe and can be taken by patient at home rather than hospitals which is also a major benefit of metronomic chemotherapy.

4. What has been achieved so far?

There have only been a small number of trials initiated since 1990, probably about a hundred or so that have been completed. Though there have been a number of randomised large phase three clinical trials and the aggregate results of which are encouraging and are showing some clinical survival or benefit.

5. What are the challenges? Are there any side effects and how does this compare with traditional chemotherapy?

The challenges that are faced by the investigators who work on metronomic chemotherapy are multiple and diverse and it is still difficult to convince many oncologists that feel giving lower doses of drug is a fruitful and logical way to go.

Oncology has been dominated by the concept for more than half a century of what is called as a maximum tolerated dose in which and you give as much dose as you possibly can to a patient without possibly killing them. This is just counter intuitive for many investigators and oncologists to accept the idea that giving lower doses of drug would be a logical thing to do.

One of my arguments is that it is not necessary that you are giving lower doses of drug because you are also giving the drug more frequently over a prolonged period of time so that the total amount that the patient is getting maybe equivalent to the traditional maximum tolerated dose types of protocols.

Economically in certain countries physicians prefer the intravenous injection rule because there is a fee for service as opposed to writing a prescription for a patient and taking an oral drug at home.

This is one of the appeals and attractions about metronomic Chemotherapy. The side effects are less. It doesn’t mean that there are no side effects. In a lot of metronomic chemotherapy protocols that have been published there was very little hair loss, very little mile of suppression, nausea, vomiting, rash or fatigue.

These are significant advantages for the quality of life of the cancer patients however significant as they may be they have to be balanced and they have to be shown that there is a actually significant benefit to the therapy.

6. Is Metronomics going to be the future of oncology?

I wouldn’t say that metronomic is the future but I see it being included and used alongside many other therapies. Investigators around the world are trying to design strategies to take one of these new immunotherapy drugs and get it to work better by combining it with something else.

It doesn’t replace the way chemotherapy is being done but rather it is used in conjunction with traditional chemotherapy and in doing so it may reduce care cost and make it more convenient for cancer care patients