Merck Challenges Rivals with Keytruda Combo in Lung Cancer Trial
Initiates Phase 3 study for oral KRAS inhibitor calderasib, aiming to secure a first-line, chemo-free therapy in a lucrative cancer market.
Merck & Co. has launched a pivotal Phase 3 clinical trial for its investigational oral cancer drug, calderasib, pairing it with the company’s blockbuster immunotherapy Keytruda for a highly sought-after group of lung cancer patients. The move signals a direct challenge to established rivals in the competitive KRAS inhibitor market and underscores Merck's strategy to expand the dominance of its flagship oncology treatment.
Shares of Merck traded up 1.35% to $108.87 in Tuesday trading, pushing the pharmaceutical giant's market capitalization over $268 billion. The stock is hovering near its 52-week high, reflecting investor confidence in the company's robust drug pipeline.
The new study, named KANDLELIT-007, will evaluate the combination as a first-line treatment for patients with advanced non-small cell lung cancer (NSCLC) whose tumors have the KRAS G12C mutation. This specific mutation, found in up to 14% of lung cancer patients, has become a major focus for drug developers. The trial aims to enroll approximately 675 patients and will test whether the combination of calderasib and a subcutaneous version of Keytruda can improve patient outcomes without the need for traditional chemotherapy.
“By pairing our oral calderasib candidate with subcutaneously administered KEYTRUDA QLEX in this trial, we will evaluate whether this chemotherapy-free combination that requires no intravenous access may help improve outcomes for patients,” said Dr. Gregory Lubiniecki, vice president of global clinical development at Merck Research Laboratories, in a statement released by the company.
The trial's primary endpoint is progression-free survival (PFS) and pits the calderasib-Keytruda duo against a control arm of Keytruda plus standard-of-care chemotherapy. Success would position Merck to offer a powerful, more convenient, and potentially less toxic initial therapy for this patient group.
This strategy is crucial for Merck as it navigates the future of its oncology franchise. Keytruda, which generated over $8 billion in the third quarter of 2025 alone, is the foundation of the company's cancer treatment portfolio. By establishing it as the backbone for next-generation combination therapies like calderasib, Merck aims to create a new standard of care and extend the drug's lifecycle ahead of its eventual patent expirations.
The push into the KRAS space places Merck in direct competition with Amgen, whose drug Lumakras was the first KRAS G12C inhibitor approved, and Bristol Myers Squibb, which acquired Mirati Therapeutics for its competitor, Krazati. While those drugs are already on the market, Merck's trial is a bold attempt to leapfrog them by targeting the larger and more lucrative first-line treatment setting with a powerful immunotherapy combination from the outset. According to market projections, the KRAS inhibitor market is a multi-billion dollar opportunity.
Wall Street analysts have maintained a largely positive outlook on Merck, with 17 analysts rating the stock as a 'Buy' or 'Strong Buy' against 12 'Hold' ratings, and an average price target of just over $110 per share. The company's deep pipeline and strategic moves to defend its key franchises are central to this thesis. For investors, the initiation of the KANDLELIT-007 trial is a significant catalyst, representing a critical step in Merck’s plan to secure its leadership in the next decade of cancer therapy.