New Cancer Drug: Breakthrough or Just Hype?
Having just passed through Ontario’s Pearson International airport on route from eastern Canada, I was struck by an email from one of my patient’s mothers who shared with me a 6/20/2013 article from the Toronto Globe and Mail, “Take news of cancer breakthrough with a big grain of salt,” by staff writer André Picard.
The author describes an announcement by two prominent cancer researchers, Tak Mak, PhD, of Princess Margaret Hospital Toronto, CA and Denis Slamon, MD, from UCLA, who reported the results from a new class of compounds known as “polo-like kinase 4 inhibitors.” Picard goes on to note, “This seemingly miraculous ‘breakthrough’ drug has not been tested on a single person. The experimental drug CFI-400945 has ‘prevented cancer growth’ in a bunch of mice.”
What troubles the author (and should probably trouble us all), is the lack of substance in this report. After all, many drugs reveal activity in animal models, yet most seemingly promising drugs fail to provide clinical benefit. Only 8 percent of cancer chemotherapy drugs that enter the earliest form of human clinical trials (Phase I) ever achieve FDA approval. According to a study published in the New England Journal of Medicine, fully 50 percent of drugs that make it to the final stage (Phase III) of clinical testing nonetheless fail to gain approval. Thus, there is ample reason for concern when “breakthrough” drugs achieve this level of public recognition, because it is distinctly unlikely that they will ever deliver on their promises.
When I attend the AACR meetings, I’m impressed by the level of scientific discovery. When I then attend the ASCO meetings, I’m even more concerned by the lack of clinically relevant progress. The divide between clinicians and scientists seems to grow ever wider. While TIME magazine and The New York Times (to use Andre Picard’s term) genuflect before these scientists’ reports of dramatic advances, most cancer patients continue to suffer through largely ineffective toxic therapies. The disconnect is becoming painfully evident. What we need is a better pathway from discovery to clinical application. What we don’t need is more hype.