Merck Pays $400 Million Upfront for SciBrunch’s KRAS G12D Molecular Glue in Deal Worth Up to $2.13 Billion

What happened

Merck announced on Monday, Sept. 28, that it has licensed exclusive global rights to SPR2015, an experimental oral cancer drug from China-based SciBrunch. According to BioSpace, Merck is paying $400 million upfront, and the deal could be worth up to $2.13 billion including milestones.

The deal has already closed. Merck said it will record a $400 million pre-tax charge, or about 13 cents per share, in the third quarter of 2026.

Deal and asset details

• Upfront: $400 million.
• Total potential value: Up to $2.13 billion.
• Rights: Exclusive global rights to develop, manufacture and commercialize SPR2015.
• Asset: An oral KRAS G12D (ON) inhibitor described as a molecular glue.
• Stage: Preclinical, with human trials expected to begin by the end of 2026.

SciBrunch was founded in late 2024 by Yang Zhang and Tao Hu and has raised $65 million, according to BioSpace. It is also running a Phase 1/2 trial of SPR1020, a PARP1 inhibitor. The Merck agreement is its first publicly announced partnership.

“This agreement complements and diversifies our expanding pipeline of precision targeted candidates,” said George Addona, Merck’s senior vice president of discovery, preclinical development and translational medicine.

Why it matters for the sector

KRAS is one of the most frequently mutated genes in cancer, and the G12D variant is common in pancreatic, colorectal and lung tumors. For decades KRAS was considered undruggable. The first approved KRAS drugs target a different mutation, G12C, and developers are now racing to address G12D and other variants. Molecular glues, which bring proteins together to change their activity, represent one of several approaches being tested.

The size of the upfront payment stands out. A $400 million upfront payment for a preclinical asset is large by industry standards and indicates a high level of confidence in the program’s preclinical data. It also reflects how much large pharma is willing to pay for differentiated oncology assets from China, where companies have moved quickly into crowded target classes.

For Merck, the deal is part of an effort to diversify its cancer pipeline as Keytruda, the world’s best-selling cancer drug, approaches patent expiration in 2028. BioSpace noted that on the same day, Merck and Daiichi Sankyo withdrew an accelerated approval request for the antibody-drug conjugate ifinatamab deruxtecan in extensive-stage small cell lung cancer after FDA feedback, a reminder of the setbacks that make pipeline breadth important.

The transaction also illustrates how quickly young Chinese biotechs can reach major licensing deals. A company founded less than two years ago, with modest venture funding, secured a nine-figure upfront payment for a single preclinical asset.

The recorded charge reflects standard accounting treatment for acquired in-process research and development when an asset has not yet reached the market.

Competition in KRAS G12D is intense. Several large and mid-sized companies have programs in development using different chemical approaches, and clinical data over the next few years are likely to determine which designs offer the best balance of efficacy and tolerability. Licensing a preclinical asset at this stage means Merck is betting on the molecule’s profile before head-to-head comparisons are possible.

What to watch

• The start of human trials for SPR2015, expected by the end of 2026.
• Early clinical data comparing SPR2015 with other KRAS G12D programs.
• Further Merck business development aimed at the post-Keytruda period.
• Whether SciBrunch signs additional partnerships for SPR1020 or other assets.

Sources: BioSpace

Decoding “KRAS G12D (ON)”

The name of the target packs in several pieces of information.

• KRAS is a protein that relays growth signals inside cells.
• G12D describes a specific mutation: at position 12 of the protein, the amino acid glycine (G) has been replaced by aspartic acid (D). That small change can keep KRAS stuck in its active state.
• ON refers to the protein’s active form. KRAS cycles between an “on” state, when bound to a molecule called GTP, and an “off” state, when bound to GDP.

The first approved KRAS drugs bind the “off” form of the G12C mutant and trap it there. Drugs that target the “on” form aim to block the protein while it is actively signaling, which some researchers believe could limit the ways tumors escape treatment. G12D is harder to target than G12C because the G12C mutation provides a reactive chemical handle that drugs can latch onto, while G12D does not.

Molecular Glues Versus Traditional Inhibitors

Traditional inhibitors

A conventional inhibitor binds directly to a pocket on its target and blocks its activity. For proteins like KRAS, which have few deep pockets, that has been very difficult.

Molecular glues

A molecular glue is a small molecule that causes two proteins to stick together when they otherwise would not, or would only weakly. Depending on the design, the result can be to block the target’s function or to mark it for destruction by the cell. In the KRAS field, some active-state approaches work by gluing KRAS to a helper protein inside the cell so that the combined complex cannot pass on growth signals. Glues are typically small enough to be taken orally, which is part of their appeal.

Understanding the Accounting Charge

When a company pays to license a drug that has not yet been approved, accounting rules generally treat the upfront payment as acquired in-process research and development. Unless the transaction qualifies as a business acquisition, that cost is usually expensed immediately rather than recorded as an asset. That is why Merck expects a one-time pre-tax charge equal to the upfront payment in the quarter the deal closed. The roughly 13 cents per share figure reflects that charge spread across Merck’s shares outstanding.

Questions Readers Ask

Which cancers commonly carry KRAS G12D?

The variant is especially frequent in pancreatic cancer and also appears in colorectal and lung cancers. Biomarker testing can show whether a patient’s tumor carries a particular mutation.

Why does a preclinical deal close so quickly?

Licensing deals for a single asset often require fewer approvals than company acquisitions, though larger transactions may still need antitrust clearance.

What is a PARP1 inhibitor?

A drug blocking an enzyme involved in DNA repair. Selective PARP1 drugs aim to keep the benefits of earlier PARP medicines with fewer side effects. Patients should discuss treatment with their own oncologists.

This article is for general information only and is not investment or medical advice.