Merck Pays $400M Upfront for a Preclinical KRAS G12D Inhibitor

The $400M Preclinical Bet

Merck has entered an exclusive license agreement with SciBrunch Therapeutics for global rights to SPR2015, an oral molecular glue inhibitor of the KRAS G12D mutation being developed for colorectal cancer, pancreatic cancer, and non-small cell lung cancer. The deal is worth up to $2.13 billion, including a $400 million upfront payment plus development, regulatory, and commercial milestones, for a still-preclinical candidate that has shown nanomolar activity and antitumor activity.

Merck paid $400 million upfront to license SciBrunch's preclinical SPR2015. SPR2015 is an oral KRAS G12D (ON) molecular-glue inhibitor and has not yet entered human clinical trials.

Who Is SciBrunch and What Is SPR2015

Merck took an exclusive global licence to develop, manufacture and commercialise SPR2015, an oral KRAS G12D (ON) inhibitor, from SciBrunch Therapeutics of Shanghai. The upfront is $400M on a preclinical molecule, and the release states that the transaction has closed.

Currently in preclinical development, SPR2015 is designed to selectively inhibit KRAS G12D, one of the most prevalent and difficult-to-treat driver mutations across multiple solid tumors, carrying significant clinical potential in pancreatic ductal adenocarcinoma, colorectal cancer, and non-small cell lung cancer.

Why KRAS G12D Is the Next Oncology Battleground

Big pharma bets on KRAS G12D as oncology race intensifies. Merck on September 28 in-licensed the rights to a KRAS G12D inhibitor developed by China's SciBrunch in a deal worth a total of $2.13 billion, including a $400 million upfront payment. In August last year, Germany's Bayer in-licensed a KRAS G12D inhibitor from US-based Kumquat Biosciences for up to $1.3 billion.

Unlike G12C which has two approved drugs, G12D has no approved targeted therapy and is more common, especially in pancreatic cancer where ∼45% of cases carry G12D. The (ON) state glue mechanism aims to lock active KRAS, potentially broader than (OFF) inhibitors.

Deal Structure and Accounting Impact

Under the terms of the agreement, Merck secures exclusive global rights covering development, manufacturing, and commercialization across all therapeutic territories. SciBrunch is to receive an upfront payment of $400 million and may receive milestone payments, with potential aggregate value of $2.13 billion.

Merck takes worldwide rights for $400 million upfront, in a deal worth up to $2.13 billion, and will book that payment as a third-quarter charge of about $0.13 a share. In a release dated September 28, Merck said it had entered an exclusive global license agreement and the transaction's potential aggregate value including upfront is $2.13 billion.

Strategic Context: Filling the Post-Keytruda Pipeline

The ruling doesn't affect the original IV version, but it complicates lifecycle management as patents for its cancer blockbuster start to expire in 2028. At the same time, Merck is spending heavily on what could come next. Just over a week ago, the pharma giant agreed to pay $400 million upfront for global rights to SciBrunch's preclinical KRAS G12D inhibitor in a deal that could ultimately be worth over $2 billion.

Merck already has a phase 3 KRAS G12C (OFF) candidate, calderasib, so SPR2015 gives it both OFF and ON coverage. The large upfront for preclinical reflects scarcity of differentiated G12D chemistry and competition from China.

Market Reaction and Biotech Dealmaker Status

Merck & Co. stock after-hours reaction was muted but positive, with Merck stock after-hours at EUR 125.35 plus 0.86% versus Lang & Schwarz prior close on deal news. Merck's Monday deal is the earliest of the week, labeled by deal trackers as a lab-stage pill aimed at KRAS G12D, a common cancer mutation with few approved drugs.

Fierce Pharma Asia noted Merck pens $2.1B deal with China's SciBrunch to chase KRAS G12D, in another large upfront for a preclinical asset, across multiple indications.

What Needs to Happen Next

Preclinical studies have reported activity against KRAS G12D-mutant models, but no human data exists. Merck must file IND, complete toxicology, and demonstrate that an oral molecular glue can achieve therapeutic window without affecting wild-type KRAS. Investors will watch for first-in-human dosing in 2027, combination plans with Keytruda and chemotherapy, and differentiation versus Revolution Medicines and Mirati successors.

The deal underscores a shift: China-origin preclinical assets now command US biotech-level upfronts when they address validated but undrugged targets.

Working Source Links:

Merck Acquires SPR2015 in $2.13 Billion Licensing Deal - SciBrunch Therapeutics - https://www.pharmexec.com/view/daily-merck-acquires-spr2015-2-billion-licensing-deal

Merck's $400M Bet on Preclinical KRAS G12D Cancer Drug - https://www.chemicalsblog.com/en/blog/ [STRIPPED 72 bytes]

Big pharma bets on KRAS G12D as oncology race intensifies - ChosunBiz - https://biz.chosun.com/en/en-science/2026/10/04/JOBUI3Z5DJDZ3K6HKDXSD2XP74/

The Weekly Term Sheet - Merck / SciBrunch $400M upfront closed - https://www.p05.org/the-weekly-term-sheet-2026-w40/

Merck Enters Exclusive Global Licensing Agreement Worth Up to $2.13B with SciBrunch for SPR2015 - https://dosedailynews.com/merck-enters-exclusive-global-licensing-agreement-worth-up-to-2-13b-with-scibrunch-therapeutics-for-next-generation-oral-kras-g12d-inhibitor-spr2015/

Merck stock after-hours at EUR 125.35 - https://www.ad-hoc-news.de/boerse/nachboerse/merck-stock-after-hours-at-eur-125-35-plus-0-86-percent-versus-lang-and/70245320