The big pharma M&A machine keeps running. Merck announced a $6.7 billion acquisition of Terns Pharmaceuticals on Wednesday, adding TERN-701—an oral allosteric BCR::ABL1 inhibitor for chronic myeloid leukemia—as the company stares down the most terrifying patent cliff in pharmaceutical history. Keytruda, generating more than $25 billion annually, loses core patent protection in 2028, and this is now Merck’s third multibillion-dollar deal in roughly a year. CEO Robert Davis called the asset a “significant driver of growth in the next decade.” Meanwhile, Maze Therapeutics delivered a genuinely historic clinical moment: the first proof-of-concept data showing an oral APOL1 inhibitor can meaningfully reduce proteinuria in genetically defined kidney disease, a condition disproportionately affecting Black Americans that has had zero targeted therapies until now. And Rocket Pharma’s Kresladi PDUFA for LAD-I gene therapy lands in two days.
Top Story: Merck Pays $6.7B to Buy Its Way Past the Keytruda Cliff
What Happened: Merck announced a definitive agreement to acquire Terns Pharmaceuticals for $53 per share in cash, an equity value of approximately $6.7 billion ($5.7 billion net of acquired cash). The deal is expected to close in Q2 2026 and will result in an approximately $5.8 billion charge (~$2.35 per share) to Merck’s results.
The Asset: TERN-701
TERN-701 is an investigational oral allosteric BCR::ABL1 tyrosine kinase inhibitor being evaluated in the Phase 1/2 CARDINAL trial for patients with chronic phase CML who have failed or are intolerant to at least one prior TKI. Unlike older CML therapies—imatinib (Gleevec), dasatinib (Sprycel), nilotinib (Tasigna)—which target the ATP-binding site on the BCR::ABL1 kinase, TERN-701 works through the ABL myristoyl pocket, a completely distinct binding mechanism.
This distinction matters because resistance mutations at the ATP-binding site are the primary reason patients fail first-line CML therapy. By targeting a different part of the protein entirely, allosteric inhibitors can maintain activity against the resistance mutations that render older drugs ineffective. The mechanism has already been validated commercially by Novartis’s Scemblix (asciminib), which targets the same myristoyl pocket and has generated strong early commercial traction since its approval.
The Valuation and the Premium Math
The $53 offer represents a modest 6% premium to Tuesday’s closing price, but a massive 42% premium to the 90-day volume-weighted average price. That discrepancy tells the real story: Terns’ stock had already surged approximately six-fold in the preceding six months on clinical data presentations and intense M&A speculation. The market had been pricing in a takeout for weeks, which compressed the headline premium on announcement day.
For Merck, the $6.7 billion price tag for a Phase 1/2 asset is a significant bet by any measure. Registrational studies have not yet started. The CARDINAL trial data is promising but early-stage, and the competitive benchmark—Scemblix—is already on market and building physician familiarity. Merck is paying a premium for the right to compete in a race that Novartis is already running.
The Keytruda Cliff: Context for the Urgency
Every Merck acquisition over the past year has been driven by the same strategic imperative. Keytruda—the world’s best-selling drug, generating more than $25 billion in 2025 revenue across dozens of oncology indications—loses core patent protection in 2028. The revenue decline from biosimilar competition will be steep, potentially erasing $15-20 billion in annual revenue within a few years of patent expiry.
This is the single largest revenue cliff any pharmaceutical company has ever faced, and it explains why Merck has now spent north of $20 billion on acquisitions in approximately 12 months. The strategy is clear: buy clinical-stage assets with blockbuster potential in therapeutic areas where Merck can leverage its existing commercial infrastructure. TERN-701 in hematology/oncology fits that playbook precisely.
The risk is equally clear. Merck is not buying de-risked, late-stage assets with Phase 3 data and clear regulatory paths. It is buying early-stage conviction—Phase 1/2 programs where the mechanism is validated but the specific asset has not yet been tested in registrational trials. That creates substantial binary risk across a portfolio of acquisitions that collectively need to replace more revenue than most pharmaceutical companies generate in total.
Our Pro brief includes a full analysis of Merck’s patent cliff arithmetic, the competitive dynamics between TERN-701 and Scemblix, and what the CARDINAL data needs to show to justify the $6.7B price tag. [Details below.]
What to Watch
The CARDINAL trial’s ongoing dose-escalation and expansion data will be the next clinical catalyst. Watch for presentations at the American Society of Hematology (ASH) meeting in December for updated response rates, duration data, and the safety profile relative to Scemblix. The transition from Phase 1/2 to a registrational program—including the FDA’s expectations for trial design in a setting where an approved allosteric inhibitor already exists—will determine the timeline and cost of bringing TERN-701 to market.
Maze Cracks the APOL1 Code with First Clinical Proof-of-Concept
What Happened: Maze Therapeutics reported positive topline data from the Phase 2 HORIZON trial of MZE829, an oral, dual-mechanism APOL1 inhibitor, in patients with broad APOL1-mediated kidney disease (AMKD). This represents the first-ever clinical proof-of-concept in this genetically defined patient population.
The Numbers
The data is striking across every subgroup measured. MZE829 delivered a 35.6% mean reduction in urine albumin-to-creatinine ratio (uACR) at Week 12 across the broad AMKD population. 50% of patients achieved greater than 30% uACR reduction. In the FSGS subgroup—the most severe form of the disease—the mean reduction reached 61.8%. In non-diabetic AMKD patients, the reduction was 48.6%.
Why APOL1 Matters: The Genetics and the Health Equity Dimension
APOL1 risk variants are carried by approximately 13% of Black Americans. These variants evolved as protection against African sleeping sickness (trypanosomiasis) but carry a devastating trade-off: they dramatically increase the risk of progressive kidney disease, including focal segmental glomerulosclerosis (FSGS), HIV-associated nephropathy, and hypertension-attributed kidney disease.
APOL1-mediated kidney disease is estimated to affect more than one million people in the United States alone. It is a major driver of the disproportionate burden of kidney failure in Black Americans—a population that develops end-stage kidney disease at approximately four times the rate of white Americans. Until Maze’s data, there has been zero approved therapy targeting the underlying genetic mechanism. Patients have been managed with the same nonspecific blood pressure medications and supportive care used for kidney disease regardless of its genetic cause.
The proof-of-concept that an oral APOL1 inhibitor can meaningfully reduce proteinuria—the key biomarker of kidney damage progression—opens a precision medicine pathway for a condition where genetic diagnosis has been possible for years but targeted treatment has not existed.
Breaking Down the FSGS Signal
The 61.8% uACR reduction in the FSGS subgroup deserves particular attention. FSGS is one of the most notoriously difficult forms of kidney disease to treat. It is a leading cause of kidney failure in young adults, and current treatment options are essentially limited to high-dose steroids, calcineurin inhibitors, and supportive care—none of which address the underlying mechanism in APOL1-driven disease.
A 62% reduction in proteinuria in FSGS patients, if it holds in a larger controlled trial, would represent a transformative clinical advance in a disease where incremental improvement has been the best-case scenario for decades. The magnitude of this response exceeds what most nephrologists would have considered plausible for an oral therapy in this population.
The Path Forward
Maze plans to advance MZE829 into a pivotal program, with $360 million in cash extending the runway into 2028. The company intends to meet with regulators to align on trial design—a critical step because APOL1-mediated kidney disease has no established regulatory pathway, and the FDA’s expectations for endpoints, trial duration, and enrichment strategy will shape the timeline and cost of the program.
Our Pro brief includes analysis of MZE829 as both a clinical and health equity story, the commercial implications of even modest penetration into the 1M+ AMKD population, and the downside risks of transitioning from a small open-label Phase 2 to a randomized pivotal trial. [Details below.]
What to Watch
The regulatory meeting to align on pivotal trial design is the immediate catalyst. The endpoints the FDA accepts—uACR reduction, eGFR slope, or a combination—will determine how long and expensive the pivotal program will be. Watch for the Phase 3 design announcement, which will clarify the registration timeline and provide the framework for modeling the commercial opportunity.
Clinical & Research Updates
Tempus AI Partners with Daiichi Sankyo on ADC Development
Tempus AI announced a strategic collaboration with Daiichi Sankyo to accelerate the clinical development of an antibody-drug conjugate program in oncology. Daiichi Sankyo will leverage Tempus’ foundation models and AI expertise, including its PRISM2 multimodal platform.
Why This Matters: Daiichi Sankyo is the global leader in ADC development—the Enhertu franchise has redefined targeted oncology across multiple tumor types. Bringing Tempus’ AI platform directly into the clinical development workflow signals a meaningful evolution in how AI is being integrated into drug development. This is not discovery-stage computational chemistry. It is AI applied to clinical trial optimization, patient selection, and biomarker identification in a late-stage commercial program. The collaboration represents the practical integration of AI into the drug development workflow that the broader industry has been promising but rarely delivering.
Rocket Pharma’s PDUFA Is Friday
Rocket Pharmaceuticals faces its March 28 PDUFA for Kresladi, a lentiviral gene therapy for leukocyte adhesion deficiency type I (LAD-I), a rare and severe immune disorder where patients suffer from recurrent, life-threatening bacterial and fungal infections. The FDA previously rejected the therapy in 2024 on manufacturing and characterization (CMC) concerns—not clinical efficacy.
Clinical data has shown Kresladi’s potential to keep patients alive, dramatically reduce infection rates, and substantially reduce hospitalization burden. If approved, Rocket receives a Rare Pediatric Disease Priority Review Voucher, which has historically been valued at $100 million to $150 million or more in secondary market transactions.
What’s at Stake: For Rocket, the PRV is not a bonus—it is a financial lifeline. The company has limited cash runway beyond Q2 2027, and a rapid PRV sale could fully fund its pivotal cardiovascular gene therapy program through its next major data catalyst. A second CRL would be devastating to investor confidence in Rocket’s manufacturing platform and its broader pipeline credibility.
Strategic Themes
1. The Keytruda Cliff Is Rewriting Merck’s Corporate Identity
Merck is no longer primarily an innovation-driven pharmaceutical company operating from internal R&D strength. It is, by necessity, becoming an acquisition-driven portfolio company racing to assemble enough late-stage and early-stage assets to offset the most significant revenue loss in industry history. The $6.7 billion Terns deal is the third multibillion-dollar acquisition in roughly a year, and collectively these deals represent a bet that external innovation—purchased at premium prices—can replace what Keytruda built over a decade of organic development. Whether that strategy works depends entirely on the clinical performance of assets that are, for the most part, still years from commercialization.
2. Precision Nephrology Just Had Its Founding Moment
Maze’s APOL1 data is not just a positive Phase 2 readout—it is the founding clinical proof-of-concept for an entire therapeutic category. APOL1-mediated kidney disease has been genetically characterized for over a decade, but pharmacological targeting of the variant has never been demonstrated in patients. The HORIZON data closes that gap and opens a precision medicine pathway that could fundamentally change how kidney disease is diagnosed, stratified, and treated in the populations most affected. If the pivotal program confirms the Phase 2 signal, MZE829 becomes one of the most significant health equity advances in modern drug development.
3. The Gene Therapy Approval Bar Remains High—and the Stakes Are Existential for Small Companies
Rocket Pharma’s Friday PDUFA is a reminder that for small gene therapy developers, a single regulatory decision can determine the company’s survival. The clinical data for Kresladi is strong. The 2024 rejection was CMC-related, not efficacy-related. But the binary nature of the outcome—approval plus a $100M+ PRV versus a second CRL that devastates manufacturing credibility—illustrates how narrow the margin is for companies whose entire financial model depends on a single regulatory event.
4. AI Integration in Drug Development Is Moving from Discovery to Clinical Operations
The Tempus/Daiichi Sankyo collaboration represents a meaningful maturation of AI’s role in pharma. The conversation has been dominated by GPU infrastructure and computational chemistry (the Roche/Lilly arms race at GTC). Tempus partnering with the global ADC leader for clinical-stage AI integration—patient selection, biomarker development, trial optimization—shows that the practical value of AI may emerge not from discovering new molecules but from making the clinical development of existing molecules more efficient and precise.
Frequently Asked Questions
Why is Merck spending so aggressively on acquisitions?
Keytruda, generating more than $25 billion annually, loses core patent protection in 2028. The anticipated revenue decline from biosimilar competition could erase $15-20 billion in annual sales within a few years. Merck has spent more than $20 billion on acquisitions in the past year to build a portfolio of assets that can collectively offset this unprecedented revenue cliff. The Terns deal is the third multibillion-dollar acquisition in that period.
What is TERN-701, and how does it compare to Scemblix?
TERN-701 is an oral allosteric BCR::ABL1 inhibitor for chronic myeloid leukemia that targets the ABL myristoyl pocket—the same binding mechanism used by Novartis’s Scemblix (asciminib). Both drugs work through a fundamentally different mechanism than older CML therapies, allowing them to overcome ATP-site resistance mutations. Merck is betting TERN-701 has a best-in-class profile, but the CARDINAL trial data is still Phase 1/2 and registrational studies have not started.
What is APOL1-mediated kidney disease, and who does it affect?
APOL1 risk variants are carried by approximately 13% of Black Americans and dramatically increase the risk of progressive kidney disease, including FSGS, HIV-associated nephropathy, and hypertension-attributed kidney disease. The condition affects more than one million people in the United States and is a major driver of the disproportionate burden of kidney failure in Black Americans. Until Maze’s data, no therapy has ever targeted the underlying genetic mechanism.
How significant is the 61.8% proteinuria reduction in the FSGS subgroup?
Extremely significant. FSGS is one of the most treatment-resistant forms of kidney disease and a leading cause of kidney failure in young adults. Current options are limited to nonspecific immunosuppression and supportive care. A 62% reduction in proteinuria in APOL1-driven FSGS, if confirmed in a larger trial, would represent a transformative advance—exceeding what most nephrologists would have considered achievable with an oral therapy in this population.
What happened with Rocket Pharma’s first Kresladi submission?
The FDA issued a Complete Response Letter in June 2024 citing manufacturing and characterization (CMC) concerns, not clinical efficacy. Rocket has addressed those issues with what the company has described as “limited” additional information aligned with the FDA. The clinical data—including 100% overall survival at 12 months with all endpoints met and no treatment-related serious adverse events—has not been questioned.
Why is the Priority Review Voucher so important for Rocket?
Rare Pediatric Disease PRVs have historically sold for $100 million to $150 million or more in secondary market transactions. For Rocket, which has limited cash runway beyond Q2 2027, selling the voucher would provide critical funding for its cardiovascular gene therapy program. The PRV is not incremental upside—it is essential to the company’s near-term financial viability.
What is the Tempus/Daiichi Sankyo collaboration about?
Tempus AI will provide its foundation models and PRISM2 multimodal platform to support Daiichi Sankyo’s antibody-drug conjugate clinical development. This represents AI integration at the clinical operations level—patient selection, biomarker identification, and trial optimization—rather than the computational chemistry applications that have dominated pharma AI headlines. Daiichi Sankyo’s position as the global ADC leader makes this a high-profile validation of clinical-stage AI utility.
What should investors watch at ACC.26 this weekend?
The American College of Cardiology meeting (March 28-30 in New Orleans) overlaps with Rocket’s PDUFA on Friday. Watch for cardiovascular outcomes data and cardio-metabolic crossover presentations, particularly anything connecting GLP-1 therapy to cardiovascular risk reduction. With Wegovy HD just launched, retatrutide in Phase 3, and orforglipron’s April 10 decision approaching, metabolic-cardiovascular data will be closely scrutinized.
BioMed Nexus Pro — What Institutional Subscribers Are Reading Today
Merck’s Patent Cliff Playbook — The Full Arithmetic. We map the $20B+ in acquisitions over the past year against the $25B Keytruda revenue base, assess what TERN-701 needs to prove against Scemblix in the CARDINAL trial, and frame the binary risk profile of building a post-patent portfolio almost entirely from Phase 1/2 assets.
APOL1 as a Health Equity Story. MZE829’s proof-of-concept matters beyond the clinical data. We analyze the commercial implications of targeting a genetically defined disease that disproportionately affects Black Americans, the regulatory pathway challenges for a novel mechanism with no established precedent, and what the transition from a 15-patient open-label study to a randomized pivotal trial really demands.
Rocket PDUFA: The Binary Setup. We frame the approval probability, the PRV monetization timeline and value, and what a second CRL would mean for investor confidence in Rocket’s manufacturing platform and the broader small-cap gene therapy sector.
Plus: ACC.26 sessions worth tracking, orforglipron countdown framing, and the updated catalyst calendar through mid-2026.
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