Once a Tiny Fraction of US Approvals, Cancer Drugs Now Dominate

Nick Mulcahy

September 19, 2019

In the 1980s, cancer drugs accounted for the smallest share (4%) of US approvals among the four major therapeutic classes (anti-infective, cardiovascular, central nervous system [CNS], and oncology).

Fast forward to the current decade and oncology drugs now top that list, with the greatest share (27%) of all American drug approvals among those four big categories, according to a new analysis published this month by the Tufts Center for the Study of Drug Development, Boston.

That's a nearly sevenfold increase over roughly 40 years, which contrasts with the twofold decreases for anti-infectives (now down to 14% of all approvals) and CNS drugs (down to 12%). Cardiovascular drugs were static.

"Oncology drug development has skyrocketed in the last 38 years, reflecting strong demand coupled with an explosion in new scientific knowledge about the pathophysiology of the disease," summarizes Joseph DiMasi, PhD, research associate professor at Tufts School of Medicine, who authored the analysis. The study period extends from 1980 to 2018, with a focus on drugs approved for the first time from 1999 through 2018.

The new findings are "not surprising" for two reasons, said Bishal Gyawali, MD, PhD, a medical oncologist at Queens Cancer Research Institute and School of Public Health Sciences, Queen's University, Kingston, Ontario, Canada.

First, cancer is largely incurable and therefore provides a broad "scope" for drugs and, second, "the bar for approval in oncology is getting lower every year," he told Medscape Medical News in an email.

"It's probably easier to get approvals in oncology than other disciplines," said Gyawali, explaining that surrogate markers such as tumor shrinkage are now commonly accepted by the FDA without validation.

Asked if cancer drug approvals are clinically wise, DiMasi responded: "I won't venture there, as I am an economist, not a clinician."

The economics of developing cancer drugs appear sound, he suggests in the new report: "Pressure for more new oncology drugs is likely to continue, driven in part by the demand for personalized medicines to treat a host of currently untreatable or inadequately treated cancers."

For the most recent years of 2014-2018, solid tumor cancer drug approvals (6.6 per year) have increased more than blood cancer approvals (4.2 per year), which is a reverse from earlier years.

Gyawali commented: "We have made so much progress in treating heme malignancies that it's difficult for newer drugs to further move the needle while most solid tumors are still at a dismal state when prognosis is concerned."

The study also found that the average regulatory "approval phase" time for cancer drugs was 48% shorter than for noncancer drugs from 1999 to 2018.

Again, Gyawali said the shorter time period (down by half since the early 2000s) was unsurprising. "No longer do drugs prove survival benefits in phase 3," he commented, adding that "this is not a good practice because although we're approving drugs faster, we don't know whether they're actually good drugs helping patients or useless/harmful drugs reaching patients sooner."

However, Gyawali appreciated the new study, despite its lack of peer-review. "This is an important analysis. It could be made further meaningful if they would break down the results by accelerated versus regular approval and approvals based on surrogates versus overall survival."

The findings summarized in the report were based on data on 594 therapeutic new drugs and biologics, both of which are referred to as drugs. A total of 126 of the drugs were in the oncology therapeutic class. Oncology drugs were only those with direct therapeutic effects. Excluded from the oncology class were drugs to treat precancerous conditions, the side effects of cancer treatments, and/or side effects of cancer.

DiMasi and Gyawali have disclosed no relevant financial relationships.

Tufts CSDD Impact Report. September/October 2019. Summary, Press Release

Follow Medscape's Nick Mulcahy on Twitter. For more from Medscape Oncology, follow us on Twitter.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: