Biotech Brief
Today's Brief

Tuesday, September 29, 2026

60 articles analyzed

Updated Sep 29, 4:56 AM · 60 sources analyzed

Today's Briefing
5-min briefing

Key Takeaways

1

Merck and Daiichi withdrew I-DXd's SCLC accelerated approval bid after FDA signaled data are insufficient — a meaningful regulatory setback for the partnership.

2

Merck separately paid $400M for global rights to a KRAS G12D inhibitor from SciBrunch, escalating competition with Revolution Medicines and Bridgebio.

3

Multiple Phase 2 and Phase 3 trial terminations today — including Takeda's AML cell therapy GDX012 and AstraZeneca's ZEAL cirrhosis program — reflect ongoing pipeline pruning across the industry.

Today's Scorecard

🏆 Winner

Merck — secured global KRAS G12D rights for $400M, strengthening its RAS oncology pipeline even as the I-DXd SCLC withdrawal clouded the same news cycle.

📉 Loser

Merck / Daiichi Sankyo — FDA's refusal to support I-DXd accelerated approval in SCLC erases a near-term commercial catalyst and resets the program to a longer development timeline.

🔭 Watch Next

Revolution Medicines' upcoming RAS(ON) inhibitor combination data readouts in late 2026 will set the clinical efficacy benchmark that all newly entering KRAS G12D programs — including Merck's SciBrunch asset — will eventually need to match.

What Matters Today5 of 5
1
Top Story10/10Market Moving

Merck and Daiichi pull I-DXd accelerated approval bid for SCLC

Merck and Daiichi Sankyo withdrew their application for accelerated approval of ifinatamab deruxtecan (I-DXd) in small cell lung cancer after the FDA signaled the existing data would not support a speedy clearance. The move erases a potential first-mover advantage in a rapidly crowding ADC (antibody-drug conjugate) space for SCLC, a cancer with few effective options and historically poor outcomes. Competitors developing ADCs in SCLC now have a clearer path to differentiation, while Merck and Daiichi face the longer road of building a fuller confirmatory dataset before reengaging regulators.

BioPharma Dive ↗
2
FDA Action8/10ImportantMRK

Merck / Daiichi Sankyo

Merck and Daiichi Sankyo withdraw FDA accelerated approval application for ifinatamab deruxtecan (I-DXd) in small cell lung cancer after the agency signaled data were insufficient for a speedy clearance.

The withdrawal removes a potential near-term approval catalyst for I-DXd in SCLC and delays Merck and Daiichi's ability to claim a labeled position in a disease with very limited options.

Why it matters

This is a meaningful setback for the Merck-Daiichi partnership's SCLC ambitions — the FDA's informal rejection effectively resets the program to a longer regulatory timeline and gives competitors in the SCLC ADC space more room to maneuver. The financial impact on the broader partnership, which carries multi-billion dollar milestone payments tied to regulatory success, warrants attention from investors modeling deal economics.

What to watch

Watch for Merck and Daiichi to announce a revised I-DXd SCLC development plan — including potential confirmatory trial design or indication pivot — within the next two quarters.

BioPharma Dive ↗
3
BioPharma Dive8/10Important

Merck and Daiichi withdraw I-DXd accelerated approval application for SCLC

The FDA indicated that data from ifinatamab deruxtecan's development program to date would not support accelerated approval in small cell lung cancer, prompting Merck and Daiichi Sankyo to withdraw the application, according to BioPharma Dive.

Why it matters

For the broader ADC field, this is a calibration event: the FDA is not rubber-stamping ADC accelerated approvals in small cell lung cancer on early single-arm data alone. Companies with SCLC ADC programs should factor in the need for more comprehensive datasets, which lengthens timelines and raises development costs.

What to watch

Watch for Merck and Daiichi to outline a revised regulatory strategy for I-DXd in SCLC — including whether they pursue a confirmatory trial design or pivot to a different indication — within the next one to two quarters.

BioPharma Dive ↗
4
Partnership7/10ImportantMRK

Merck

Merck pays $400M for global rights to SciBrunch Therapeutics' KRAS G12D inhibitor candidate, adding a China-sourced asset to its RAS-targeted oncology portfolio.

The deal gives Merck a seat at the KRAS G12D table alongside Revolution Medicines and Bridgebio, expanding the competitive field and raising the stakes for clinical programs already in human testing.

Why it matters

Merck is making a calculated bet that KRAS G12D will become a validated oncology target class — paying $400M for global rights to an early-stage asset suggests the company believes the first-mover clinical data from rivals will prove out the biology. The China-sourced chemistry angle also reflects a broader industry trend of accessing novel small-molecule IP from Chinese biotech.

What to watch

Watch for Merck to disclose the development stage of the SciBrunch asset and its preclinical differentiation data, which will determine whether this is a pipeline-building investment or a near-term IND-ready program.

MedCity News ↗
5
MedCity News7/10Important

Merck acquires KRAS G12D inhibitor from China-based SciBrunch for $400M

Merck secured global rights to a SciBrunch Therapeutics drug candidate targeting KRAS G12D, a mutated protein that drives tumor growth, in a deal valued at $400 million, according to a news report.

Why it matters

Merck is paying to stay relevant in RAS-targeted oncology at a moment when rivals are further along clinically; the $400M price tag for a preclinical or early-stage asset reflects how scarce differentiated KRAS G12D chemistry has become. For Revolution Medicines and other clinical-stage KRAS players, this deal confirms Big Pharma appetite but also signals that the competitive clock is accelerating.

What to watch

Watch for Revolution Medicines' RAS(ON) inhibitor combination data readouts in late 2026 and early 2027, which will set the efficacy bar that SciBrunch's asset will eventually need to clear.

MedCity News ↗
In Depth
Clinical Readouts5 stories
5/10Notable
Oncology
ClinicalTrials.gov
Corcept TherapeuticsCORT·RelacorilantPhase 3
Industry Update ℹ️

The Phase 3 trial evaluating relacorilant in combination with nab-paclitaxel is active but no longer recruiting. Primary endpoints are progression-free survival by blinded independent central review and overall survival. Full data have not yet been released.

Why it matters

Platinum-resistant ovarian cancer has limited treatment options, making this a commercially meaningful indication if relacorilant can demonstrate a survival benefit on top of nab-paclitaxel.

Analysis

Corcept has built its franchise on cortisol modulation, and relacorilant in ovarian cancer is the company's bid to move beyond its mifepristone-based legacy into oncology. The trial's active-not-recruiting status suggests enrollment is complete and a data readout is approaching — the key question is whether the glucocorticoid receptor antagonism hypothesis translates into a survival signal in this refractory population.

What to watch

Watch for the primary PFS and OS data readout, likely presented at a major oncology meeting in late 2026 or early 2027, which will determine whether Corcept has a viable oncology franchise.

RegulatoryMedium
ClinicalTrials.gov ↗
4/10Minor
Oncology
ClinicalTrials.gov
TakedaTAK·GDX012Phase 2
Program Discontinued 🛑

The Phase 1/2 study of GDX012, a novel cell therapy for AML, has been terminated. No efficacy or safety data have been released from this trial.

Why it matters

AML cell therapy remains a high-attrition space, and another termination signals that durable responses in this genetically heterogeneous malignancy continue to be difficult to achieve with novel cell-based approaches.

Analysis

Takeda's termination of GDX012 adds to a pattern of cell therapy programs struggling in AML, where rapid disease progression and a hostile tumor microenvironment have frustrated even well-resourced developers. For Takeda's pipeline, the discontinuation frees resources but narrows its near-term AML options.

What to watch

Watch for any Takeda disclosure on the reason for termination — safety signal versus futility — which would carry implications for the broader AML cell therapy field.

PatientsMedium
CommercialHigh
CompetitiveHigh
RegulatoryMedium
ClinicalTrials.gov ↗
4/10Minor
Respiratory
ClinicalTrials.gov
Boehringer Ingelheim·BI 1839100Phase 2
Program Discontinued 🛑

The Phase 2 study evaluating BI 1839100 for chronic cough in IPF and PPF has been terminated. No efficacy or safety outcome data were disclosed in the registry entry.

Why it matters

IPF-associated cough is an underserved symptom target; another termination here underscores that symptom-focused endpoints in fibrotic lung disease remain difficult to prosecute and that even well-resourced sponsors are trimming their IPF pipelines.

Analysis

Boehringer Ingelheim is one of the dominant players in IPF through nintedanib, making this termination noteworthy as it suggests the company is recalibrating its cough-focused mechanistic bet in fibrosis rather than expanding the franchise. Investors in smaller cough-pathway players should note that a well-resourced operator has stepped back from this indication.

What to watch

Watch for Boehringer to disclose a reason for termination at a respiratory congress — if safety-driven, it would cast a shadow on the broader BI 1839100 mechanism class.

PatientsMedium
CommercialHigh
CompetitiveHigh
RegulatoryMedium
ClinicalTrials.gov ↗
4/10MinorClinicalTrials.gov
AstraZenecaAZN·Zibotentan + DapagliflozinPhase 2
Program Discontinued 🛑

The ZEAL study, a Phase 2a/b randomized, double-blind, placebo-controlled, dose-ranging trial of zibotentan combined with dapagliflozin in liver cirrhosis, has been terminated. No efficacy or safety data were disclosed in the registry entry.

Why it matters

The ZEAL termination removes one of the more novel mechanistic combinations in portal hypertension — pairing an endothelin receptor antagonist with an SGLT2 inhibitor — from a competitive field that has seen growing interest in targeting the hemodynamic consequences of cirrhosis.

Analysis

AstraZeneca had positioned ZEAL as a potential entry into cardiorenal-metabolic complications of cirrhosis, leveraging dapagliflozin's established cardiovascular profile alongside zibotentan's vasodilatory mechanism. The termination signals either a safety issue or a lack of proof-of-concept, which matters for developers pursuing hemodynamic approaches in cirrhosis.

What to watch

Watch for AstraZeneca to disclose termination rationale at a hepatology conference such as AASLD in late 2026, which would clarify whether the endothelin + SGLT2 combination concept retains viability.

PatientsMedium
CommercialHigh
CompetitiveHigh
RegulatoryMedium
ClinicalTrials.gov ↗
5/10Notable
Oncology
ClinicalTrials.gov
BeOne MedicinesONC·Sonrotoclax (BGB-11417)Phase 2
Industry Update ℹ️

The Phase 1/2 study of sonrotoclax monotherapy in relapsed or refractory mantle cell lymphoma is active and no longer recruiting. Part 1 of the study determines maximum tolerated dose and recommended Phase 2 dose; Part 2 evaluates efficacy at the selected dose. Detailed efficacy data have not yet been released.

Why it matters

Sonrotoclax is a next-generation BCL-2 inhibitor (a protein that helps cancer cells survive) designed to improve upon venetoclax; data in mantle cell lymphoma would test whether the compound can carve out space in a BTK inhibitor-dominated disease setting.

Analysis

BeOne's sonrotoclax is one of the most closely watched BCL-2 inhibitor candidates in development, and enrollment completion in MCL moves the readout timeline closer. The investment thesis hinges on whether sonrotoclax shows deeper or more durable responses than venetoclax in BTK inhibitor-pretreated patients.

What to watch

Watch for BeOne to present sonrotoclax efficacy data from this MCL cohort at ASH 2026 in December, which would be the first major clinical signal for the compound in this indication.

PatientsMedium
ClinicalTrials.gov ↗
FDA Watch1 item
8/10ImportantFDA Action
Oncology
MRK

Merck / Daiichi Sankyo

Merck and Daiichi Sankyo withdraw FDA accelerated approval application for ifinatamab deruxtecan (I-DXd) in small cell lung cancer after the agency signaled data were insufficient for a speedy clearance.

Why it matters

The withdrawal removes a potential near-term approval catalyst for I-DXd in SCLC and delays Merck and Daiichi's ability to claim a labeled position in a disease with very limited options.

Analysis

This is a meaningful setback for the Merck-Daiichi partnership's SCLC ambitions — the FDA's informal rejection effectively resets the program to a longer regulatory timeline and gives competitors in the SCLC ADC space more room to maneuver. The financial impact on the broader partnership, which carries multi-billion dollar milestone payments tied to regulatory success, warrants attention from investors modeling deal economics.

What to watch

Watch for Merck and Daiichi to announce a revised I-DXd SCLC development plan — including potential confirmatory trial design or indication pivot — within the next two quarters.

CommercialMedium
CompetitiveMedium
RegulatoryHigh
BioPharma Dive ↗
Deal Flow1 item
7/10ImportantPartnership
Oncology
MRK

Merck

Merck pays $400M for global rights to SciBrunch Therapeutics' KRAS G12D inhibitor candidate, adding a China-sourced asset to its RAS-targeted oncology portfolio.

Why it matters

The deal gives Merck a seat at the KRAS G12D table alongside Revolution Medicines and Bridgebio, expanding the competitive field and raising the stakes for clinical programs already in human testing.

Analysis

Merck is making a calculated bet that KRAS G12D will become a validated oncology target class — paying $400M for global rights to an early-stage asset suggests the company believes the first-mover clinical data from rivals will prove out the biology. The China-sourced chemistry angle also reflects a broader industry trend of accessing novel small-molecule IP from Chinese biotech.

What to watch

Watch for Merck to disclose the development stage of the SciBrunch asset and its preclinical differentiation data, which will determine whether this is a pipeline-building investment or a near-term IND-ready program.

CommercialHigh
CompetitiveHigh
MedCity News ↗
Pipeline Pulse3 items
7/10Important
Oncology
MedCity News

Merck acquires KRAS G12D inhibitor from China-based SciBrunch for $400M

Merck secured global rights to a SciBrunch Therapeutics drug candidate targeting KRAS G12D, a mutated protein that drives tumor growth, in a deal valued at $400 million, according to a news report.

Why it matters

The deal validates continued industry conviction in selective KRAS G12D inhibition as a viable oncology target class, intensifying competition with clinical-stage programs at Revolution Medicines and Bridgebio in an already active space.

Analysis

Merck is paying to stay relevant in RAS-targeted oncology at a moment when rivals are further along clinically; the $400M price tag for a preclinical or early-stage asset reflects how scarce differentiated KRAS G12D chemistry has become. For Revolution Medicines and other clinical-stage KRAS players, this deal confirms Big Pharma appetite but also signals that the competitive clock is accelerating.

What to watch

Watch for Revolution Medicines' RAS(ON) inhibitor combination data readouts in late 2026 and early 2027, which will set the efficacy bar that SciBrunch's asset will eventually need to clear.

MedCity News ↗
8/10Important
OncologyADCs
BioPharma Dive

Merck and Daiichi withdraw I-DXd accelerated approval application for SCLC

The FDA indicated that data from ifinatamab deruxtecan's development program to date would not support accelerated approval in small cell lung cancer, prompting Merck and Daiichi Sankyo to withdraw the application, according to BioPharma Dive.

Why it matters

The FDA's informal signal raises the evidentiary bar for ADC (antibody-drug conjugate) accelerated approval in SCLC and suggests the agency wants to see more robust response depth or durability before granting a speedy pathway in this indication.

Analysis

For the broader ADC field, this is a calibration event: the FDA is not rubber-stamping ADC accelerated approvals in small cell lung cancer on early single-arm data alone. Companies with SCLC ADC programs should factor in the need for more comprehensive datasets, which lengthens timelines and raises development costs.

What to watch

Watch for Merck and Daiichi to outline a revised regulatory strategy for I-DXd in SCLC — including whether they pursue a confirmatory trial design or pivot to a different indication — within the next one to two quarters.

BioPharma Dive ↗
5/10Notable
Oncology
ClinicalTrials.gov

Loxo Oncology Phase 3 trial of pirtobrutinib vs. bendamustine-rituximab in untreated CLL completes enrollment

The Phase 3 study comparing pirtobrutinib (LOXO-305) to bendamustine plus rituximab in previously untreated chronic lymphocytic leukemia is fully enrolled and active, according to ClinicalTrials.gov.

Why it matters

Pirtobrutinib's non-covalent BTK inhibition mechanism (blocking a key cancer survival enzyme by a reversible binding approach) is designed to work in patients who have progressed on earlier BTK inhibitors, and front-line data against a chemotherapy backbone would substantially expand its commercial opportunity if positive.

Analysis

Eli Lilly, which acquired Loxo Oncology, is positioning pirtobrutinib for a front-line CLL label to compete with AstraZeneca's acalabrutinib and AbbVie's ibrutinib; a win here against bendamustine-rituximab would be commercially meaningful but may not answer the more important question of how pirtobrutinib compares to next-generation BTK inhibitors head-to-head.

What to watch

Watch for the primary PFS readout from this Phase 3 trial, expected in 2027, which would form the basis of a front-line CLL regulatory submission for pirtobrutinib.

ClinicalTrials.gov ↗
🔭Biotech CalendarNext catalyst to watch
Viking TherapeuticsVKTX·VK2735 (oral)
Obesity·Phase 3 data·Q3 2026·PoS 65%
💡Why It Matters

Oral GLP-1 competing directly with Lilly and Novo. Best-in-class efficacy in Phase 2 at ~15% weight loss. Phase 3 success could make Viking an M&A target.

★What We're Watching Next1 hit today
RVMDRevolution MedicinesDeal

Merck's $400M acquisition of SciBrunch's KRAS G12D inhibitor directly intensifies competition with Revolution Medicines, which has clinical-stage RAS(ON) inhibitor programs in the same molecular target class. Revolution remains the most advanced pure-play KRAS G12D developer, but the SciBrunch deal signals Big Pharma is moving aggressively to close that gap.

MedCity News ↗

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