Merck/Gilead Discontinue Lung Cancer Trial as Pfizer, Roivant Report Pipeline Updates

Merck and Gilead Sciences have discontinued the Phase 3 KEYNOTE-D46/EVOKE-03 study, while Pfizer has initiated a new Phase 1 trial and Roivant Sciences has completed enrollment in its Phase 2 PHocus trial, marking a week of significant clinical pipeline updates across the pharmaceutical industry.

Merck and Gilead Sciences announced on June 8, 2026, the discontinuation of the Phase 3 KEYNOTE-D46/EVOKE-03 study investigating Trodelvy in combination with KEYTRUDA versus KEYTRUDA monotherapy in patients with previously untreated metastatic non-small cell lung cancer whose tumors expressed PD-L1 with a tumor proportion score ≥50%. The decision was based on a recommendation from the external Data Monitoring Committee following review of pre-specified final analysis of progression-free survival and interim analysis of overall survival. A numerical improvement in PFS was observed but did not reach statistical significance, and the probability of achieving statistically significant overall survival is unlikely at the planned final analysis. The safety profile of the combination was consistent with the known safety of each agent with no new safety signals identified.

The study had enrolled approximately 620 patients across global sites, with dual primary endpoints of progression-free survival and overall survival. Regulatory authorities have been informed, and investigators and patients will be advised of the recommendation. These data will be presented at a future medical meeting. Trodelvy is currently approved in more than 60 countries for second-line or later metastatic triple-negative breast cancer and in more than 50 countries for certain patients with pre-treated HR+/HER2- metastatic breast cancer.

Meanwhile, Pfizer has announced an update on its ongoing clinical study, a Phase 1 randomized, double-blind, placebo-controlled trial evaluating the pharmacokinetics, safety and tolerability of single ascending oral doses of PF-08057418 in healthy adult participants. The study aims to assess how the new drug behaves in the body and its tolerability through a randomized crossover design where participants receive both the study drug and placebo at different times. The trial is currently recruiting, with first submission on May 4, 2026, and the latest update filed on May 25, 2026.

In another development, Pulmovant, a Roivant Sciences subsidiary, has completed enrollment in the Phase 2 PHocus trial of mosliciguat for pulmonary hypertension associated with interstitial lung disease. Mosliciguat is being evaluated as a potential first-in-class therapy for PH ILD, a serious condition with limited treatment options. The completion of enrollment marks a key operational step as the program advances toward Phase 2 data readouts.

Roivant Sciences (NasdaqGS:ROIV) stock is currently at $26.45, up 2.4% over the past week, 14.4% over the past month, and 20.6% year to date. The stock trades about 20% below the average analyst target of $31.73. One flagged risk is significant insider selling over the past three months.