Clinical trials have, in many cases, changed the world of cancer from that of managing uniformly deadly diseases to striving for chronic care or even cure. Carefully observing patients to understand which treatments work best has led to cure in the vast majority of patients with early stage cancers, or with advanced and metastatic cancers like testicular cancer, Hodgkin lymphoma and acute lymphoblastic leukemia (ALL). To know best how and when to use a new treatment, patients who receive it must be carefully monitored for side effects and for tumor response, and that is the fundamental idea behind a clinical trial.
One of the principles in all of medicine is to balance the risks of a treatment with the potential for benefit. In the past, most new treatments for cancer had the potential to be very toxic. For that reason, when the treatment was new, patients were only exposed to the risk of a toxic treatment if their chance of gaining benefit from some other treatment was very low. If a new treatment tested among patients with advance or refractory cancers should some signs of working, it was then moved into testing among patients with less refractory cancer until it was ultimately tested side by side with the standard treatment to pick the winner. This way of designed trials was important to balance risk with benefit with toxic cancer treatments.
But we are entering into a new era, in which the treatments to be tested are often more precise in targeting what pathway is broken in a cancer cell and avoiding widespread damage to normal cells. This dramatically changes the way we will design trials, as the risks to treatment are lower and the benefit to treatment among those patients who’s cancer has a particular pathway increases. No longer will cancer clinical trials be thought of only for those patients who have run out of options. Instead, cancer clinical trials will allow patients with new diagnoses to access new combinations of drugs that target the broken pathways in their own tumor cells.
More than ever, these new cancer clinical trials will require patients to get involved, and do so early after a diagnosis. It won’t be good enough to find 100’s of patients with lung cancer or breast cancer to learn about a treatment on a clinical trial. To help the patient and to learn enough to help similar patients in the future, trials will need to include 100’s of lung cancer or breast cancer patients with each of perhaps a handful of broken pathways. Examples are present today. Lung cancer with changes in a pathway called EGFR may benefit from the addition of targeted treatment with gefitinib or erlotinib. Breast cancer patients with changes in a pathway called HER-2 may benefit from the additional of targeted treatment with trastuzumab.
To make progress in these new types of cancer treatments, and for individual patients to best access these treatments when they are in development, more people should consider participating in a cancer clinical trial, and do so earlier after a diagnosis is made.