Shares of Merck jumped about 4.7% in morning trade following a positive interim readout from the OptiTROP-Lung05 Phase 3 study. The trial reported that the combination of sacituzumab tirumotecan (sac-TMT) - an antibody-drug conjugate developed in partnership with Kelun Biotech - plus Merck’s immunotherapy Keytruda demonstrated superior efficacy compared with Keytruda on its own in patients with non-small cell lung cancer (NSCLC).
The OptiTROP-Lung05 interim finding is a meaningful development for Merck’s oncology program. Keytruda already holds a leading position in immuno-oncology, particularly in first-line NSCLC, and positive data from combination studies may further reinforce its role as a backbone therapy as the company and partners continue to evaluate new regimens.
Alongside the sac-TMT result, Merck will be presenting a broader set of oncology data at the upcoming American Society of Clinical Oncology (ASCO) meeting. The company highlighted that the ASCO showing will include extensive data that illustrate the breadth of its pipeline, reinforcing investor focus on Merck’s development momentum in cancer therapeutics.
Merck’s progress extends beyond the sac-TMT lung program. The company noted promising Phase 3 trial results for TroFuse and reported collaborations in colorectal cancer studies, signaling multiple active fronts in oncology research. These clinical advances are part of a wider strategic push into chronic disease markets as well, as indicated by the company’s efforts to expand in areas such as Hepatitis A and chronic kidney disease.
Regulatory developments have also contributed to investor enthusiasm. The European Medicines Agency’s Committee for Medicinal Products for Human Use (CHMP) issued a positive opinion recommending approval of Keytruda in combination with Padcev for patients with cisplatin-ineligible resectable muscle-invasive bladder cancer. A final decision from the European Commission is expected by the third quarter of 2026.
Financial results provided additional support for the stock’s move. Merck reported first-quarter 2026 earnings that beat analyst expectations on both earnings per share and revenue. Management subsequently raised the company’s full-year revenue guidance, which market participants interpreted as confirmation of operational strength, particularly within the oncology segment.
The broader U.S. equity market offered a constructive backdrop to Merck’s gain. On the day, the S&P 500 was trading up approximately +0.5%, the Dow Jones Industrial Average was up about +0.7%, and the NASDAQ was higher by roughly +0.5% - a tone consistent with a risk-on session across major indexes. The Pharmaceuticals & Medical Research sector moved modestly higher, while Merck outpaced its industry peers because of these company-specific developments.
Analyst sentiment remains generally favorable. Among covering firms, the average recommendation stands at "Buy" from 29 analysts, and the 12-month consensus price target is $129.74. Market watchers pointed to the convergence of the OptiTROP-Lung05 interim readout, the CHMP recommendation for a Keytruda-Padcev combination in bladder cancer, and the stronger-than-expected Q1 results with raised guidance as the principal drivers prompting investors to re-rate the stock today.
In sum, the combination of a headline Phase 3 NSCLC result for sac-TMT, additional supportive regulatory news in Europe, and encouraging financial performance contributed to the significant upward movement in Merck’s share price. The company’s expanding oncology pipeline and recent clinical and regulatory milestones were central to the market’s reassessment.