This new cancer capitalism, though, is also a little-known tale of scientific gamesmanship. An empire of drugs grew out of the companies’ ability to exploit one specific marker: a measure of tumor growth known as “progression-free survival.” An obscure term used primarily by doctors until a standardized definition appeared in an academic journal in 2000, it’s since become a common justification for the FDA’s expedited approval of treatments. Researchers assumed that if a drug delayed the growth of tumors, it would also extend life. Recent studies have found the link is not so clearcut, and even one of the originators of the measure calls it arbitrary.
Congress in 1992 had approved a “user fee” program under which drug companies funded a share of the FDA’s budget. In return, the agency agreed to speed up reviews of some drugs it deemed priority applications to as little as six months. A 1997 law had further eased approval standards, allowing the agency to fast-track certain drugs without its traditional requirement of two “well-controlled trials.”
Progression-free survival was easier to demonstrate than actual survival; they just had to keep tumor growth below that magic 20% threshold for as little as one period of scanning, typically six to eight weeks. By the mid-2000s, the FDA increasingly started approving cancer drugs based on their ability to slow tumor growth, with the idea that the metric would reliably predict which drugs extended patients’ lives.
Sometimes it did. Often, it didn’t. A
review in the European Journal of Cancer found that two-thirds of drug trials aiming to slow progression of solid tumors were deemed successful from 1999 to 2015. This turned out to be a surprisingly poor predictor of whether patients live longer — which happened in only 38% of those cases.
Costs, meanwhile, radiate across the health system. An
analysis of Medicare found that annual spending on oncology drugs more than doubled in the four years ending in 2020, to $53.9 billion. By comparison, Trump’s Health and Human Services Department has said it would save taxpayers $1.8 billion a year by reducing its workforce to 62,000 from 82,000.
One of FDA commissioner Makary’s first major hires, UC San Francisco cancer doctor Vinay Prasad, is a critic of the overuse of expedited approvals who has questioned the lack of survival evidence for some cancer drugs. As head of the FDA’s Center for Biologics Evaluation and Research, he won’t oversee most cancer treatments, which remain in Pazdur’s division. But he may have the commissioner’s ear.
