What changed, and when

Merck and Terns announced on 25 Mar 2026 that they entered a definitive agreement under which Merck will acquire Terns for $53.00 per share in cash, implying an approximate equity value of $6.7 billion. (Merck announcement, Terns release, Reuters)

The structure is a tender offer followed by a merger, subject to customary conditions including HSR clearance and majority tender, with expected close in Q2 2026. (Terns 8-K, Merck announcement)

60-second thesis frame

What Merck is really buying is not current revenue, but control of TERN-701, an oral allosteric BCR::ABL1 inhibitor in Phase 1/2 CARDINAL for previously treated Ph+ chronic-phase CML, plus a shot at a differentiated position in a market where speed and depth of molecular response, tolerability, and post-asciminib utility matter. (Merck announcement, ClinicalTrials.gov, NCT06163430)

Confidence goes up if 2026 data continue to show strong major molecular response durability, clean cardiovascular and pancreatic tolerability, and usefulness in patients already exposed to asciminib. (Merck announcement, Terns 2026 priorities, Reuters)

Confidence goes down if TERN-701 proves merely “another allosteric” rather than meaningfully better than current CML options, especially as Novartis’ asciminib has already established the myristoyl-pocket mechanism commercially and clinically. (SCEMBLIX FDA label, Novartis approval release)

The seven diligence questions

Clinical

• Does updated 2H26 CARDINAL evidence preserve the early efficacy signal, especially major molecular response and deep molecular response by week 24, in a broader and more mature dataset? (Merck announcement, Terns 2026 priorities, Reuters)
• How much real differentiation does TERN-701 have in asciminib-exposed and mutation-defined patients, including T315I and other resistance mutations, versus simply extending the same mechanism one step later in the algorithm? (Terns 2026 priorities, ClinicalTrials.gov, NCT06163430, SCEMBLIX FDA label)

Payer or Access

• If Merck reaches approval, will payers require failure on generic ATP-site TKIs, then asciminib, before reimbursing TERN-701, limiting earlier-line uptake? This is inference from today’s line-of-therapy positioning and existing CML treatment sequencing. (SCEMBLIX FDA label, ClinicalTrials.gov, NCT06163430)
• Can Merck build a payer story around lower discontinuation risk, cleaner monitoring burden, or better mutation coverage, rather than relying only on molecular response data? (Merck announcement, Terns 2026 priorities)

Ops or Adoption

• Does Merck accelerate development materially, with pivotal dose selection in mid-2026, End-of-Phase 2 interaction in mid-2026, and first pivotal trial initiation in late 2026 or early 2027, or does integration slow the clock? (Terns 2026 priorities, Merck announcement)

Competitive

• Is the commercial prize big enough to justify the price, given Reuters cited analyst views on multi-billion-dollar peak sales but also noted investor concern around the modest premium versus last close and the still-early stage of the asset? (Reuters, Fierce Biotech)

Team or Cap table

• Was Merck effectively forced to pay ahead of proof because Terns had enough capital runway, approximately $1.0 billion at year-end 2025, to hold for more data and negotiate from strength? (Terns 2026 priorities, Merck announcement)

Red flags

• Early-stage assets can rerate sharply on durability and safety, and TERN-701 is still in Phase 1/2, not registrational readout territory. (Merck announcement, ClinicalTrials.gov, NCT06163430)
• The mechanism is validated, but that also means the benchmark is real, asciminib already owns the “first allosteric” narrative and sets a high bar for differentiation. (SCEMBLIX FDA label, Novartis approval release)
• The transaction economics are front-loaded, Merck expects asset-acquisition accounting and a roughly $5.8 billion charge in 2026, before registrational de-risking. (Merck announcement, Reuters)

Next catalyst

The cleanest near-term catalyst is updated and expanded CARDINAL data in 2H26, alongside pivotal dose selection and an End-of-Phase 2 FDA interaction targeted for mid-2026. (Terns 2026 priorities, Merck announcement)

FAQ

What exactly changed by Merck’s “Merck to Acquire Terns Pharmaceuticals” news on 25 Mar 2026, and why does it matter for CML?

Merck agreed to acquire Terns in an all-cash deal at $53.00 per share, implying about $6.7 billion of equity value. (Merck announcement, Terns release, Reuters)

It matters because the asset underpinning the transaction is TERN-701, an investigational oral allosteric BCR::ABL1 inhibitor in Phase 1/2 development for previously treated chronic-phase CML, where differentiation versus current TKIs and asciminib could matter clinically and commercially. (Merck announcement, ClinicalTrials.gov, NCT06163430)

What is the regulatory path after the Merck/Terns acquisition, and what are the next formal steps in the US, UK, and EU?

For the deal itself, the immediate formal steps are commencement of the tender offer, Terns filing its Schedule 14D-9 recommendation, and satisfaction of conditions including HSR clearance and majority tender. (Terns 8-K, Merck announcement)

For the asset, the company had guided to pivotal dose selection and a U.S. FDA End-of-Phase 2 interaction in mid-2026, then pivotal-trial initiation in late 2026 or early 2027. Public signal on MHRA or EMA-specific next steps is limited at this stage, so the operative read-through remains U.S.-led development planning. (Terns 2026 priorities)

Which endpoints in the CARDINAL trial drove the result cited in the 2026 news, and how meaningful was the effect size?

Merck highlighted encouraging rates of major molecular response and deep molecular response by week 24, and Reuters reported an early-study 75% major molecular response figure in previously treated patients. (Merck announcement, Reuters)

The meaningfulness is that CML investors and prescribers care not just about initial MMR, but depth, time to response, durability, and performance after prior TKI or asciminib exposure, so the mature 2H26 dataset matters more than the headline alone. (Terns 2026 priorities, SCEMBLIX FDA label)

What safety issues matter post-Terns acquisition, and do they change real-world use?

Merck said the majority of treatment-emergent adverse events seen to date were low grade, with low incidence of severe events and discontinuations, low rates of lipase elevation, and no clinically meaningful blood-pressure changes observed. (Merck announcement)

That matters because tolerability and monitoring burden can influence both prescriber sequencing and payer positioning in a disease where patients may remain on therapy for long periods. The caveat is straightforward, this remains early-stage evidence and needs confirmation in larger, later-line and mutation-enriched populations. (ClinicalTrials.gov, NCT06163430, Terns 2026 priorities)

How will Merck manage Terns’ existing metabolic pipeline assets like TERN-601 and TERN-501?

While the acquisition focuses on oncology, Terns had previously shifted its metabolic assets, including the oral GLP-1 TERN-601, to a partner-funded model (The Chronicle-Journal). Merck may integrate these assets into its own cardiometabolic franchise or seek to out-license them to external partners (Pharmaphorum).

Publisher / Disclosure

Publisher: LucidQuest Ventures Ltd. Produced: 25 Mar 2026, 22:29 London. Purpose: general and impersonal information. Not investment research or advice, no offer or solicitation, no suitability assessment. UK: directed at investment professionals under Article 19(5) and certain high-net-worth entities under Article 49(2)(a)–(d) of the Financial Promotion Order 2005. Others should not act on this. Sources and accuracy: public sources believed reliable, provided “as is,” may change without notice. No duty to update. Past performance is not reliable. Forward-looking statements carry risks. Methodology: questions-first framework using public sources. No conflicts. Authors do not hold positions unless stated. © 2026 LucidQuest Ventures Ltd. ( Time check )

Entities / Keywords

Merck; MSD; Terns Pharmaceuticals; TERN; TERN-701; chronic myeloid leukemia; CML; Ph+ CML; BCR::ABL1; BCR-ABL1; allosteric inhibitor; myristoyl pocket; CARDINAL; NCT06163430; asciminib; Scemblix; Novartis; tyrosine kinase inhibitor; TKI; MMR; deep molecular response; T315I; M244V; F359I; F359C; F359V; FDA; Orphan Drug Designation; Fast Track; HSR; tender offer; Schedule TO; Schedule 14D-9; SEC; hematology; oncology; Keytruda; patent cliff; Rahway; Foster City; RBC Capital Markets; Leerink Partners

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