Welcome to our dedicated page for Merck & Co news (Ticker: MRK), a resource for investors and traders seeking the latest updates and insights on Merck & Co stock.
Merck & Co., Inc. (NYSE: MRK), known as MSD outside the United States and Canada, generates frequent news across human health, animal health and corporate finance. As a research-intensive biopharmaceutical company with more than a century of history developing medicines and vaccines, Merck regularly announces clinical trial milestones, regulatory decisions, business development transactions and capital markets activity.
Recent news highlights include oncology updates from Merck’s extensive KEYTRUDA program, such as positive Phase 3 data in muscle-invasive bladder cancer and new trials in non-small cell lung cancer using combinations like calderasib (MK-1084) with KEYTRUDA QLEX. The company also reports on progress in other therapeutic areas, including pulmonary arterial hypertension with WINREVAIR, Alzheimer’s disease candidates MK-2214 and MK-1167, and cardiovascular research with the oral PCSK9 inhibitor candidate enlicitide.
Investors following MRK news will also see announcements related to Merck Animal Health, such as the conditional U.S. FDA approval of EXZOLT CATTLE-CA1 for the prevention and treatment of New World screwworm larvae and the treatment and control of cattle fever tick, as well as updates on acquisitions like the planned merger with Cidara Therapeutics to add the influenza candidate CD388 to Merck’s respiratory portfolio.
Corporate and financial communications include quarterly earnings calls, participation in major healthcare conferences and disclosures about note offerings under the company’s shelf registration statement. This news page aggregates these developments so readers can review clinical, regulatory, strategic and financial updates related to Merck & Co., Inc. and its MRK stock in one place.
Merck (NYSE: MRK) will present new cardio-pulmonary data at the AHA Scientific Sessions 2025 in New Orleans, Nov 7–10, 2025. Key items include first detailed Phase 3 results from the CORALreef Lipids trial (enlicitide decanoate) and the CORALreef HeFH trial, plus a pooled mortality and major morbidity analysis for WINREVAIR (sotatercept) from PULSAR, STELLAR and ZENITH.
An investor event is scheduled Nov 9, 2025, 6:00 p.m. CT with a live webcast and call access for investors and the public.
Merck (NYSE: MRK) said the FDA granted priority review for two sBLAs seeking approval of KEYTRUDA and KEYTRUDA QLEX, each combined with Padcev, for patients with muscle-invasive bladder cancer (MIBC) who are ineligible for cisplatin. The FDA set a PDUFA date of April 7, 2026. The applications are based on Phase 3 KEYNOTE-905 (EV-303) results with median follow-up 25.6 months: event-free survival reduced EFS events by 60% (HR=0.40), overall survival risk of death reduced by 50% (HR=0.50), and pathologic complete response rose to 57.1% vs 8.6% (increase 48.3 percentage points).
Merck (NYSE: MRK) presented a systematic literature review at IDWeek 2025 summarizing 15 U.S. studies (2015–2025) and CDC ABC surveillance on pneumococcal serotypes targeted by CAPVAXIVE (21‑valent) versus PCV20. The review found CAPVAXIVE‑unique serotypes were more prevalent in U.S. adults with pneumococcal disease and showed higher antimicrobial resistance in some serotypes.
Key figures: in adults ≥65 years, CAPVAXIVE‑unique serotypes accounted for 34.8% of invasive disease vs 8.5% for PCV20‑unique; ages 50–64: ~30% vs ~15%. Reported resistance included serotype 35B (penicillin 96%, erythromycin 89%) and 23A (penicillin 72%, erythromycin 46%); multidrug resistance was highest for 19F (42%) and 23A (27%). CAPVAXIVE is indicated for adults ≥18 and reportedly covers ~84% of IPD in adults 50+ vs ~52% for PCV20 (CDC ABC 2018–2022).
Merck (NYSE: MRK) reported long-term analyses showing sustained survival benefit for KEYTRUDA (pembrolizumab) in non-small cell lung cancer (NSCLC) across earlier and advanced stages, presented at ESMO Congress 2025.
KEYNOTE-671 five-year exploratory follow-up showed improved overall survival (HR=0.74) and event-free survival (HR=0.58) for perioperative KEYTRUDA plus chemotherapy versus chemotherapy-placebo, with five-year OS rates of 64.6% versus 53.6% and five-year EFS rates of 49.9% versus 26.5%. Long-term (8–10 year) follow-ups of KEYNOTE-001/010/024/042 also showed durable OS benefits versus chemotherapy in selected PD-L1 populations.
Merck (NYSE: MRK) broke ground on a $3 billion, 400,000-square-foot Center of Excellence for Pharmaceutical Manufacturing at its Elkton, Virginia site on October 20, 2025. The facility will house Active Pharmaceutical Ingredient and Drug Product capabilities for small molecule manufacturing and testing and is expected to potentially create more than 500 full-time roles plus 8,000 construction jobs.
This project is part of a broader plan to invest more than $70 billion beginning in 2025 to expand U.S. manufacturing and R&D; Merck also cited nearly $6 billion in U.S. manufacturing investments announced in 2025 and forecasts 48,000+ construction-related jobs by 2029.
Merck (NYSE: MRK) and Daiichi Sankyo reported Phase 2 REJOICE-Ovarian01 results for raludotatug deruxtecan in platinum-resistant ovarian, primary peritoneal and fallopian tube cancer (data cut-off Feb 26, 2025).
Key outcomes: a confirmed objective response rate of 50.5% (n=107) across three doses, disease control rate 77.6%, and median time to response ~7.1 weeks. The 5.6 mg/kg dose was selected for Phase 3. Safety: common TEAEs included nausea, anemia, asthenia and neutropenia; 3.7% had treatment-related ILD/pneumonitis. R-DXd received Breakthrough Therapy Designation from FDA in Sept 2025.
Merck (NYSE: MRK) reported first and second interim results from the Phase 3 KEYNOTE-B96 trial in platinum-resistant recurrent ovarian cancer presented at ESMO 2025.
Key clinical results: at 15.6-month median follow-up KEYTRUDA+chemotherapy ± bevacizumab reduced risk of progression or death by 30% (HR=0.70) in all comers; 12-month PFS 33.1% vs 21.3%. At 26.6-month follow-up KEYTRUDA reduced risk of death by 24% (HR=0.76) in PD-L1 CPS≥1 patients; 12-month OS 69.1% vs 59.3% and 18-month OS 51.5% vs 38.9%.
Safety signals included higher Grade 3–5 TRAEs (67.5% vs 55.3%) and immune-mediated AEs (39.1% vs 18.9%). The FDA accepted an sBLA for priority review with a PDUFA date of Feb 20, 2026.
Merck (NYSE: MRK) reported Phase 3 KEYNOTE-905/EV-303 results showing perioperative KEYTRUDA (pembrolizumab) plus Padcev (enfortumab vedotin) reduced the risk of event-free survival (EFS) events by 60% (HR=0.40; p<0.0001) and reduced the risk of death by 50% (HR=0.50; p=0.0002) versus surgery alone in cisplatin-ineligible or -declining muscle-invasive bladder cancer (MIBC) patients after a median follow-up of 25.6 months.
Median EFS was not reached for the combination versus 15.7 months for surgery alone. Pathologic complete response (pCR) rose to 57.1% with the combination versus 8.6% with surgery (increase of 48.3 percentage points; p<0.000001). Safety showed higher treatment-emergent adverse events with the combination (100% vs 64.8%; Grade ≥3: 71.3% vs 45.9%). Results were presented at ESMO 2025 and the companies plan to share data with regulators worldwide.
Merck (NYSE: MRK) and Eisai reported five-year results from the Phase 3 KEYNOTE-775/Study 309 trial showing durable survival benefit for KEYTRUDA (pembrolizumab) plus LENVIMA (lenvatinib) versus chemotherapy in advanced endometrial carcinoma after prior platinum therapy.
In the pMMR subgroup at median follow-up 68.8 months, five-year OS was 16.7% vs 7.3%, median OS 18.0 vs 12.2 months (HR 0.70). All-comers five-year OS was 19.9% vs 7.7%, median OS 18.7 vs 11.9 months (HR 0.66). Safety was consistent with prior data; no new signals.
Merck (NYSE: MRK) announced that the Phase 3 KEYNOTE-B96 trial met its secondary endpoint of overall survival (OS) in all comers with platinum-resistant recurrent ovarian cancer when KEYTRUDA (pembrolizumab) was added to paclitaxel with or without bevacizumab.
The regimen previously met the primary endpoint of progression-free survival (PFS) and earlier OS analyses in PD-L1–expressing tumors; the final analysis showed a statistically significant and clinically meaningful OS benefit in all comers. Safety was consistent with prior studies and no new safety signals were identified. Final results will be presented at an upcoming medical meeting.