PD-1 Backbone Contracts Across U.S. Clinical Trial Pipeline as Keytruda Slide Extends
核心洞察
Pembrolizumab (Keytruda) lost 13 recruiting trials from June to July 2026, falling from 425 to 412, with sponsors dropping from 236 to 225 and conditions from 820 to 790.
The broader PD-1 (搜索)/PD-L1 (搜索) field tilted negative, with nivolumab, atezolizumab, cemiplimab, and durvalumab all losing trials, signaling a class-wide contraction rather than a single-program wind-down.
GLP-1 growth concentrated in leaders semaglutide (up four trials to 29) and tirzepatide (up one), while retatrutide declined from three to two trials.
The U.S. clinical trial recruiting pipeline grew by a net 79 drugs between June and July 2026, but beneath that headline of modest expansion, the PD-1 (搜索)/PD-L1 (搜索) checkpoint inhibitor backbone is contracting across the board, according to the July 2026 U.S. Clinical Trial Recruiting Pipeline Report from WhichTrial.com (搜索). The report, authored by Andrew Beauchamp and derived from the public ClinicalTrials.gov registry, tracks U.S.-based recruiting trials across 17 condition categories and roughly 50 metro areas.
Over the single-month window, 355 drugs picked up additional recruiting trials, 322 lost ground but retained at least one open study, and 10,879 held flat. As the report notes, individual moves over one month are small by nature, so the analysis pairs the raw tables with a continuity check on drugs tracked since the prior issue.
Keytruda's Retreat Deepens, and Its Shape Matters
Pembrolizumab (Keytruda) lost 13 recruiting trials between June and July, sliding from 425 to 412. More telling than the headline count, however, is the composition of the decline: the number of distinct sponsors running pembrolizumab studies fell from 236 to 225, and the number of conditions attached to those trials narrowed from 820 to 790.
"Fewer organizations are running it against a narrower set of indications, which is a wider retreat than the trial count alone suggests," the report states. This pattern, the authors argue, does not reflect a single program winding down. Rather, "the PD-1 (搜索) backbone is contracting across the board."
Nivolumab showed the same pattern at a smaller scale, down six trials and eight sponsors. The broader checkpoint field tilted negative, with atezolizumab, cemiplimab, and durvalumab also losing recruiting trials in the prior month's data. The exceptions remained the China-origin checkpoint inhibitors, which continued to gain ground, including toripalimab, which added a trial, a sponsor, and three conditions.
GLP-1 Class Grows on Its Leaders, Not Breadth
The GLP-1 receptor agonist class continued to expand, but the growth concentrated in its two leaders rather than broadening across the field. Semaglutide added four recruiting trials, rising from 25 to 29, and picked up two sponsors and two additional conditions — described in the report as "the clearest expansion in the group."
Tirzepatide barely moved, up one trial and one sponsor. Retatrutide moved in the opposite direction, falling from three trials to two and from seven conditions to five, while remaining on a single sponsor. "The class is growing on the back of its two leaders rather than broadening out," the report concludes.
TROP2 ADC Watch: A Quiet Month
Sacituzumab tirumotecan (sac-TMT), the TROP2 (搜索)-directed antibody-drug conjugate previously flagged as a drug to watch, sat perfectly still at 22 trials, five sponsors, and 31 conditions — unchanged from June in every column. "For a drug we flagged as one to watch, a month of zero movement in either direction is its own kind of signal," the report observes.
Pipeline Turnover
Four hundred and eighty drugs that had at least one recruiting trial in June no longer did so in July. Over a one-month window, these are typically long-tail compounds with one or two trials that wrapped enrollment. On the entry side, 559 drugs began recruiting between June and July that had not previously appeared in the snapshot, most of them early-phase, single-sponsor studies representing first signals of new programs.
Methodology and Limitations
All figures derive from the public ClinicalTrials.gov registry, queried monthly. A trial is counted as recruiting when its overall status is flagged RECRUITING; when a trial no longer appears in the monthly fetch, it is marked "not recruiting," which may reflect completed enrollment, suspension, termination, or a move to active-not-recruiting status. The report's extraction filters out generic terms such as placebo, chemotherapy, radiation, and saline, as well as intervention names longer than 60 characters, and deduplicates drugs appearing under multiple aliases where possible.