PD-1 inhibitor R&D tapering off as newer oncology molecules capture attention: IQVIA

Move over PD-1, your time has passed. At least, that’s the sense from IQVIA’s latest report, which suggests development of immuno-oncologics such as PD-1/PD-L1 checkpoint inhibitors has started to “taper off” as the once-hot R&D area is usurped by newer targeted molecules.

A total of 1,236 trials testing these inhibitors launched globally in 2022. While this is a significant increase on the 2017 level of just 804 trial starts, it still marks an 11% drop on the number of study launches in 2021.

In its latest report into global oncology trends, IQVIA pinpointed 2018 as the moment when the “significant growth” in R&D of PD-1/PD-L1 checkpoint inhibitors switched to a gradual tapering off in interest. The research slowdown indicates “a crowded market and switch to even newer targeted molecules.”

Of the more than 3,000 late-stage PD-1/PD-L1 trials ongoing in 2022, 81% were being conducted in a single country. By far the biggest player is China, which alone conducted 1,287 late-stage trials for these checkpoint inhibitors last year. The fact these studies were being carried domestically reflects the likelihood that “the drugs being tested in these trials may not be bound for international markets.”

The most common use of PD-1/PD-L1 inhibitors in trials globally was as a combo treatment, with over 80% of all studies seeing the drugs used alongside other therapies targeting a total of almost 300 different targets and pathways.

PD-1/PD-L1 inhibitors burst onto the scene with the approval of Merck & Co.’s blockbuster Keytruda in 2014. Since then, six other checkpoint inhibitors have received the FDA green light, including household names like Bristol Myers Squibb’s Yervoy and Roche’s Tecentriq.

While they may be beginning to fall out of favor with R&D teams, the checkpoint inhibitors on the market are continuing to prove their worth. The drug class accounted for $41 billion in global spend in 2022, of which almost half related to lung or kidney cancer.

Overall, the amount spent on cancer medicines rose 4% to hit $196 billion last year, which IQVIA said was “driven by new medicines and increases in access but offset by savings from biosimilars and generics.”

For PD-1/PD-L1 checkpoint inhibitors specifically, the “wide adoption” of these therapies “reflects their strong efficacy across a range of solid tumors, including several with tissue-agnostic approvals, triggering their use with biomarker testing results,” IQVIA said.

The analytics company noted that uptake of these drugs “varied considerably” between countries, with the U.S. and France using almost three times as many of these inhibitors as the U.K. or South Korea.

“Looking ahead, many PD-1/PD-L1 inhibitors are being used as combination therapies with other molecules, as they’re becoming backbone treatments in certain tumor types,” IQVIA concluded. “This trend is expected to continue with PD-1/PD-L1 inhibitor global spending expected to exceed $70 billion in 2027.”

They may no longer be turning heads in R&D labs, but it sounds like when it comes to mainstream oncology treatment, checkpoint inhibitors are here to stay.