Gauri Bhide MD

View Original

How to choose the right drug for cancer treatment?

When oncologists recommend a treatment, we go by the results of trials which tell us which is the optimal treatment for that condition at that time. The gold standard for standard of care is a randomized controlled trial (RCT). The current standard treatment is compared to the new treatment and patients are assigned to their treatments by the organizer of the trial . This randomization is designed to avoid bias and balance the distribution of similar patients in the different arms of the study.  As the treating oncologist, I can’t assign Julie to the new treatment arm because I believe she will do better on it. If we do not have a trial without bias, we just don’t know. For example, oncologists once believed a bone marrow transplant would be better for some of their metastatic breast cancer patients because they thought more was better, till a trial proved them wrong. We don’t want to give stronger and ineffective treatment if all it gives you is more toxicity.

We are living in an era of a happy explosion of new drugs, targets against a variety of mutations in receptors and growth signals. However, while adding to the armamentarium of options, the process has added to the confusion of how to sequence these new options. Often, these new drugs get their “fast track” approvals by being compared to a placebo, not the current standard of care. The new drug then tries to distinguish itself by marketing the marginal changes in the convenience of dosing schedules, for example. The doctor is left comparing apples to oranges, wondering now which is truly the better drug.

The F.D.A and other organizations are hoping that the ongoing collection of data after the release of the new drug and its use in the general patient population. This is called Real World Experience (RWE) data. Certainly this information can be useful on how the drug is actually being used. The new categories of drugs which are being released for specific mutations can be potentially used in a variety of cancers, as long as the targeted mutation is present. This has widened the scope of targeted therapy. Unfortunately, the comparison of the different drugs in a non standardized setting may not yield the sequencing guidance we are looking for. So when you see an advertisement on TV about a new drug being used for your kind of cancer, it may not yet be a proven winner. We need better tools for guidance, and unfortunately at the moment, marketing is the winner.