On October 24, 2025 Zai Lab Limited (NASDAQ: ZLAB; HKEX: 9688) reported updated data from the global Phase 1 clinical trial of zocilurtatug pelitecan (zoci), formerly known as ZL-1310, (NCT06179069) demonstrating robust and durable responses in heavily pre-treated patients with extensive-stage small cell lung cancer (ES-SCLC). This data will be presented as an oral presentation and was included as part of the press program at the AACR (Free AACR Whitepaper)-NCI-EORTC AACR-NCI-EORTC (Free AACR-NCI-EORTC Whitepaper) International Conference on Molecular Targets and Cancer Therapeutics (EORTC-NCI-AACR) (Free ASGCT Whitepaper) (Free EORTC-NCI-AACR Whitepaper), held October 22–26, 2025, in Boston, Massachusetts.

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"The strong and durable antitumor activity we have observed with zoci, alongside a well-tolerated safety profile, highlights its potential to be a best-in-class, DLL3-targeted antibody-drug conjugate for small cell lung cancer," said Rafael G. Amado, M.D., President, Head of Global Research and Development, Zai Lab. "Advancing this program from Phase 1 to a global, registrational study in less than two years reflects the speed, scientific rigor, and executional excellence of our team, and marks a major milestone for Zai Lab as we advance our global programs. Furthermore, we are rapidly expanding zoci’s development into other areas of high unmet need, including first-line small cell lung cancer and neuroendocrine carcinoma, both expected to enter the registrational phase next year."

The presentation includes updated results from the Phase 1 monotherapy dose escalation and dose expansion portion of the study from 115 patients across six dose cohorts (0.8 mg/kg, 1.2 mg/kg, 1.6 mg/kg, 2.0 mg/kg, 2.4 mg/kg, and 2.8 mg/kg) as of the data cut-off date of September 15, 2025. 102 patients had the opportunity of at least one post-baseline tumor assessment per Response Evaluation Criteria in Solid Tumors version 1:1 (RECIST v1.1).

All patients in this multicenter study had progressed following platinum-based chemotherapy, and 90% of patients had progressed after immune checkpoint inhibitors. Of all patients, 44% had failed two prior lines of therapy, making this a highly pretreated population with limited therapeutic options. Eleven patients received a prior DLL3 bi-specific antibody. A total of 32% of patients had brain metastases at baseline. This study included patients in the United States, Spain, and China.

Key efficacy results include (n=102):

Zoci demonstrated a high response rate across all dose levels in patients with ES-SCLC who progressed on or after platinum-based chemotherapy. Efficacy was consistent over time with additional patients and longer follow-up.
In a subset of patients (n=53) receiving zoci as a second-line treatment, the best overall response rate (ORR) observed among patients in the 1.6 mg/kg arm (n=19) was 68%.
A high response rate was also observed in patients (n=32) with brain metastasis at baseline, including an ORR of 80% for patients without prior brain radiotherapy.
Three out of seven patients who progressed after prior tarlatamab, responded. Enrollment of tarlatamab pretreated patients continues.
The estimated median duration of response (DoR) is 6.1 months, and median progression-free survival is 5.4 months across all doses and all lines of therapy. Responses were durable and clinically meaningful in this heavily pre-treated and difficult-to-treat population. In the dose finding cohort of the study, enrollment continues for 1.2 mg/kg and 1.6 mg/kg, with nearly half of responders still ongoing at data cut-off. Enrollment is expected to complete in Q4 2025.
Responses occurred early in treatment with a median time to confirmed objective response of 6 weeks.
Key safety findings include (n=115):

Zoci continues to demonstrate a well-tolerated safety profile with longer follow-up, particularly at the 1.2 or 1.6mg/kg dose level.
In the 1.6 mg/kg dose cohort, Grade 3 or higher treatment-related adverse events (TRAE) occurred in 13% of patients and serious TRAEs occurred in 9%. No patients were discontinued due to toxicity.
There were two cases of pneumonitis and interstitial lung disease, both Grade 1, in the 72 patients treated at 1.2 or 1.6 mg/kg dose.
Across all dose cohorts, Grade 3 or higher TRAEs occurred in 20% of patients and serious TRAEs in 8%. The most common Grade 3 or higher TRAEs were anemia (10%) and neutropenia (11%). There were five patients who discontinued due to TRAEs, all in the higher dose levels.
"DLL3 represents a validated target in extensive-stage small cell lung cancer, where there is high need for new therapies given the disease’s aggressive nature and limited treatment options," said Grace Dy, M.D., Roswell Park Comprehensive Cancer Center, Buffalo, NY, and study investigator. "These new Phase 1 results for zoci, including data that show rapid and sustained responses among the patient population, especially those with poor prognostic factors, are the latest clinical evidence that further demonstrate zoci’s potential as a differentiated, DLL3-targeted ADC."

Global Phase 3 Registrational Study Opens for Patient Enrollment

The Phase 3 registrational clinical trial of zoci is a multicenter study that will enroll approximately 665 patients globally, including in North America, Asia, and Europe. The randomized, open-label study is designed to further evaluate the safety and efficacy of zoci compared to investigator’s choice single agent therapy (ICT) in patients with relapsed SCLC who have progressed on or after platinum-based first-line therapy as second-line therapy or one line of chemotherapy followed by tarlatamab. The primary endpoints are ORR assessed by Blinded Independent Central Review (BICR) per RECIST v1.1 for interim analysis and overall survival as the primary analysis. Secondary endpoints include duration of response, progression-free survival and safety.

To learn more about the Phase 3 clinical trial program and study locations, please visit ClinicalTrials.gov (identifier: NCT07218146).

Zai Lab will hold an investor conference call and webcast to highlight updated zoci data presented at the 2025 AACR (Free AACR Whitepaper)-NCI-EORTC International Conference and outline next steps in clinical development.

Details regarding the webcast and conference call are as follows:

Date/Time: October 24, 2025, at 11 a.m. ET / 11 p.m. HKT, please register at:
Webcast presentation (preferred): View Source
Dial-in: View Source
Presenter: Rafael G. Amado, M.D., President and Head of Global Research and Development, Zai Lab

Details regarding the zoci oral presentation are as follows:

Title: Phase 1 trial of ZL-1310, a DLL3-targeted ADC, in patients with previously treated extensive-stage small cell lung cancer
Presenter: Grace K. Dy, M.D., Roswell Park Comprehensive Cancer Center, Buffalo, NY
Session Title: Plenary Session 3: Antibody Drug Conjugates
Date/Time: Friday, October 24, 2025, 9:17 a.m. – 9:27 a.m. ET (presentation), 9:27 a.m. – 9:45 a.m. ET (panel discussion)
Location: Hynes Convention Center, Level 3, Ballroom AB

About Small Cell Lung Cancer and Zocilurtatug Pelitecan (zoci)

Small cell lung cancer (SCLC) is one of the most aggressive and lethal solid tumors, accounting for ~15% of the approximately 2.5 million patients diagnosed with lung cancer worldwide each year1,2. Additionally, two-thirds of all SCLC patients are diagnosed at extensive stage3.

DLL3 is an antigen overexpressed in many neuroendocrine tumors, such as SCLC, and is often associated with poor clinical outcomes. Zocilurtatug pelitecan (zoci), formerly known as ZL-1310, comprises a humanized anti-DLL3 monoclonal antibody connected via a cleavable linker to a novel camptothecin derivative (a topoisomerase 1 inhibitor) as its payload. The compound was designed with a novel ADC technology platform called TMALIN, which leverages the tumor microenvironment to overcome challenges associated with first-generation ADC therapies.

Zoci received an Orphan Drug Designation from the U.S. Food and Drug Administration (FDA) in January 2025, recognizing its potential to treat patients with SCLC.

About the Webcast and Conference Call

All participants must use the link provided above to complete the online registration process in advance of the conference call. Dial-in details will be in the confirmation email which the participant will receive upon registering.

A replay will be available shortly after the call and can be accessed by visiting the Company’s website.

(Press release, Zai Laboratory, OCT 24, 2025, View Source [SID1234656995])

On October 24, 2025 Parabilis Medicines, a clinical-stage biopharmaceutical company committed to creating extraordinary medicines for people living with cancer, reported preliminary clinical and preclinical findings across its Helicon peptide pipeline at the AACR (Free AACR Whitepaper)-NCI-EORTC AACR-NCI-EORTC (Free AACR-NCI-EORTC Whitepaper) International Conference on Molecular Targets and Cancer Therapeutics (EORTC-NCI-AACR) (Free ASGCT Whitepaper) (Free EORTC-NCI-AACR Whitepaper) in Boston, Massachusetts.

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The findings reinforce the broad potential of FOG-001, the company’s lead investigational therapy and the first-ever direct Wnt/β-catenin:TCF inhibitor, to act across a range of rare and more prevalent solid tumors linked by the same dysregulated biology of the Wnt/β-catenin pathway. Single-agent activity resulting in tumor shrinkage by at least 30% (partial response (PR)) was observed in five low-complexity tumor types, with strong scientific support as well for FOG-001’s potential in combination therapy for more complex tumors, including microsatellite-stable colorectal cancer (MSS CRC).

Together with positive preclinical read-outs demonstrating pharmacologic proof of concept for the company’s discovery-stage Helicon peptides in prostate cancer targeting the ERG and active androgen receptor (ARON) targets, these data highlight how the company’s Helicon platform can repeatably target high-impact "undruggable" targets long considered inaccessible to conventional therapeutic approaches.

"Just one week after presenting the first clinical proof that β-catenin:TCF can be drugged, we are showing the breadth of what this breakthrough could mean for science and for patients," said Mathai Mammen, M.D., Ph.D., Chairman and CEO of Parabilis Medicines. "FOG-001 is demonstrating meaningful signs of clinical activity across multiple Wnt/β-catenin-driven tumors, supporting its continued development in both simpler and more biologically complex Wnt-driven cancers through both monotherapy and combination therapy approaches."

He added, "Together with our preclinical advances in prostate cancer, the data illustrate the potential of Helicons to take on some of the toughest problems in oncology and bring forward transformative medicines that could meaningfully improve outcomes for patients."

FOG-001 Clinical and Preclinical Findings

The Wnt/β-catenin pathway — first identified as a key cancer driver over 30 years ago — is implicated in millions of cancer cases annually, spanning many rare and prevalent solid tumors as well as diseases like familial adenomatous polyposis (FAP) that predispose individuals to certain cancers, including colorectal cancer and desmoid tumors. Despite its central role in cancer biology, the pathway’s critical β-catenin:TCF transcription complex has long been considered "undruggable."

Preliminary data from the ongoing Phase 1/2 trial of FOG-001 (NCT05919264), as of mid-August 2025, show that the therapy is well tolerated with no Grade 4/5 treatment-related adverse events or discontinuations and exhibits a favorable pharmacokinetic profile. As of this early data cut, an objective response rate (ORR) of 43% and a disease control rate (DCR) of 73%, per RECIST 1.1, were observed in non-CRC patients with Wnt pathway activating mutations (WPAM). Evidence of single-agent activity was observed across numerous Wnt/β-catenin–driven tumors, particularly in those with low mutational burden, including desmoid, adamantinomatous craniopharyngioma (ACP), ameloblastoma, salivary gland cancer, and solid pseudopapillary neoplasm (SPN).

In MSS CRC, a 50% DCR was achieved within the efficacious monotherapy dose range, with molecular data confirming on-target pathway inhibition and reprogramming of the tumor microenvironment toward a more immune-active state. Complementary preclinical studies demonstrated that FOG-001 enhances the effects of standard and emerging therapies for MSS CRC—showing in these preclinical models additive or synergistic activity with each of 5-fluorouracil and anti-VEGF regimens, synergy with anti–PD-1 therapy, and combination benefit with pan-RAS and KRAS G12D inhibitors.

Together, these findings highlight FOG-001’s broad pipeline potential — warranting continued development in Wnt pathway–activated low-complexity tumors, and as a backbone for rational combination regimens in more complex cancers. The Phase 1/2 study remains ongoing across a wide range of Wnt-driven rare and common cancers, with additional data readouts expected over the coming months.

Prostate cancer pipeline expansion

Parabilis also presented preclinical data advancing its prostate cancer franchise, focused on two long-standing oncogenic drivers that currently lack effective therapies. ERG-degrading Helicon peptides potently and durably reduced ERG protein levels —overexpressed in 40–50% of prostate cancers — showing in vivo pharmacologic proof-of-concept demonstrating tumor growth inhibition and efficacy comparable to or exceeding standard of care in challenging prostate cancer models.

In parallel, allosteric ARON Helicon degraders that bind a conserved site distinct from the androgen ligand pocket, were designed to selectively target the active, agonist-bound androgen receptor. These Helicon degraders block proliferation in AR-amplified prostate cancer cells, offering a strategy to overcome resistance driven by AR mutations or amplification. Importantly, this approach also allows for effective combinations with approved and emerging treatments that target the testosterone ligand pocket. Together, these data demonstrate the repeatability of the Helicon platform in addressing high-value, historically undruggable targets in oncology.

"Our Helicons are delivering against three of the most challenging and compelling targets in oncology, from β-catenin:TCF to ERG to ARON," said Fawzi Benzaghou, M.D., Chief Medical Officer of Parabilis Medicines. "By pursuing bold science that makes the undruggable druggable, we’re opening new therapeutic possibilities for patients with few or no options. These data reinforce the power of our α-helical peptide platform to repeatedly unlock difficult targets and advance medicines with the potential for extraordinary patient impact."

About the Phase 1/2 trial of FOG-001
FOG-001 is being evaluated in a first-in-human Phase 1/2 multicenter, open-label study (NCT05919264) assessing its safety, tolerability, pharmacokinetics, pharmacodynamics, and antitumor activity. The trial includes dose-escalation and dose-expansion phases and is testing FOG-001 both as a monotherapy and in combination with other anticancer agents in patients with advanced or metastatic solid tumors likely or known to harbor a Wnt pathway–activating mutation (WPAM).

About FOG-001
FOG-001 is an investigational first-in-class competitive inhibitor of β-catenin interactions with the T-cell factor (TCF) family of transcription factors and is currently in clinical development. By directly targeting the β-catenin:TCF protein-protein interaction, FOG-001 is intended to block the Wnt signaling pathway irrespective of the various APC and β-catenin mutations that typically drive disease.

FOG-001 combines key features that distinguish it from previously reported Wnt/β-catenin pathway modulators: FOG-001 acts inside the cell where it binds directly to the key oncogenic driver β-catenin; and FOG-001 blocks the Wnt pathway at the key downstream node, disrupting the interaction between β-catenin and the TCF transcription factors, thereby abrogating the signal transmission by which Wnt pathway mutations are believed to drive oncogenesis.

FOG-001 is currently being evaluated in a first-in-human Phase 1/2 clinical trial in patients with locally advanced or metastatic solid tumors.

(Press release, Parabilis Medicines, OCT 24, 2025, View Source [SID1234656994])

On October 24, 2025 ChemDiv reported the extension of its discovery and early development partnership with Mondego Bio to advance the company’s best-in-class immuno-oncology program targeting PTPN2. The announcement follows Mondego Bio’s successful Series A financing led by Biovance Capital with participation from OrbiMed Advisors and Torrey Pines Investment, underscoring strong momentum behind Mondego’s strategy.
ChemDiv previously supported the accelerated discovery of a drug candidate by Eilean Therapeutics LLC in the U.S., which preceded the establishment of

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Mondego Bio in Portugal in 2025. Leveraging rational drug design across reversible, covalent, and allosteric inhibitors, the collaboration established a differentiated selectivity profile that delivers high oral bioavailability, robust in vivo efficacy, and strong safety and tolerability—hallmarks of potentially best-in-class cancer therapeutics.

Medicinal chemistry and scale-up were led by ChemDiv’s group in Germany, while pharmacology and translational biology were supported by ChemDiv facilities in the U.S. and Portugal. Together, these efforts advanced Mondego’s pre-IND program, supported by its European venture capital–backed launch.

Looking ahead, ChemDiv will continue to provide:

Medicinal chemistry and discovery biology for backup series,
CMC process research and large-scale manufacturing of the lead candidate for non-GLP and GLP animal studies,
Computational and wet-lab pharmacology to accelerate clinical readiness.
These efforts build on ChemDiv’s deep expertise in designing selective kinase and phosphatase inhibitors, leveraging its extensive kinase and phosphatase chemical libraries, and applying parallel lead optimization supported by AI/ML-enabled rational design, ADME/DMPK, and translational capabilities.

"We’re moving fast with Mondego to translate PTPN2 biology into medicines," said Ilya Baimetov, COO and Head of Digital Platforms at ChemDiv.
"By combining our advanced rational design, medchem horsepower, and focused tool libraries with Mondego’s cutting-edge immuno-oncology platform, we are advancing the next generation of phosphatase inhibitors with best-in-class potential."

(Press release, ChemDiv, OCT 24, 2025, View Source [SID1234656993])

On October 24, 2025 Whitehawk Therapeutics, Inc. (Nasdaq: WHWK), an oncology therapeutics company applying advanced technologies to established tumor biology to efficiently deliver improved antibody drug conjugate (ADC) cancer treatments, reported data from a real-world analysis of Protein Tyrosine Kinase 7 (PTK7) at the 2025 AACR (Free AACR Whitepaper)-NCI-EORTC AACR-NCI-EORTC (Free AACR-NCI-EORTC Whitepaper) International Conference on Molecular Targets and Cancer Therapeutics (EORTC-NCI-AACR) (Free ASGCT Whitepaper) (Free EORTC-NCI-AACR Whitepaper). As part of a collaboration between Whitehawk and Tempus AI, the analysis evaluated real-world data from the Tempus AI database and the Clinical Proteomic Tumor Analysis Consortium to, for the first time, robustly characterize PTK7 expression.

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PTK7 is an oncofetal transmembrane pseudokinase that drives early embryonic development, has restricted expression in adult tissues and frequent overexpression in a wide range of cancers. There are no approved PTK7-directed ADCs.

This large-scale RNA analysis of >157,000 tumor samples, nearly half from metastatic lesions, confirms PTK7 as one of the most broadly and highly expressed targets across solid tumors, reinforcing its potential as a clinically meaningful pan-tumor ADC target, and further support development of HWK-007, Whitehawk’s PTK7-directed ADC candidate.

Key findings include:

PTK7 is expressed in ~70% of solid tumors.
PTK7 is the third most highly expressed tumor marker among clinically validated and emerging ADC targets, after HER2 and HER3.
Highest median PTK7 mRNA expression1 observed in endometrial (7.4), ovarian (7.2), head and neck (7.1), non-small cell lung cancer (NSCLC) (6.9) and breast (6.7) tumors.
Stable expression across disease stages and metastatic status, underscoring relevance in both early- and late-stage disease.
Expression levels comparable to or exceeding clinically validated and emerging ADC targets:
Lung cancer: Comparable to HER2, HER3, Trop-2 and cMET.
Ovarian cancer: Comparable to HER2 and FRα; markedly higher than CDH6, B7-H4 and CLDN6.
Endometrial cancer: Comparable to Trop-2; markedly higher than FRα, B7-H4 and HER2.
"These results emphasize the translational potential of PTK7 as a broadly expressed and stable target across solid tumors," said Grace Dy, MD, Chief, Thoracic Oncology, Professor of Oncology, Department of Medicine, Roswell Park Comprehensive Cancer Center. "By demonstrating consistent expression across histologies, disease stages and sample types, this analysis builds on the foundational rationale for developing next-generation ADCs that have the potential to reach a wide range of patients."

Whitehawk is advancing HWK-007, a PTK7-targeting ADC that leverages an advanced ADC technology platform which consists of a highly stable yet cleavable linker that delivers a Topoisomerase I (TOPO1) inhibitor payload. The Company plans to submit an Investigational New Drug application to the U.S. Food and Drug Administration for HWK-007 by year-end, with initial clinical evaluation planned in NSCLC, ovarian and endometrial cancers.

"These findings reinforce PTK7’s promise as one of the most compelling and underexplored ADC targets in oncology," said Dave Lennon, PhD, President and Chief Executive Officer, Whitehawk Therapeutics. "As the third most abundant tumor marker across all cancer patients – present in approximately 70% of solid tumors – the opportunity for HWK-007 has never been clearer. We believe we are well positioned to develop a differentiated ADC that could have a meaningful impact for the nearly 750,0002 patients in the US with PTK7-expressing cancers."

The analysis was conducted as part of a previously announced collaboration between Whitehawk and Tempus AI. The abstract is available as a freely available supplement in the AACR (Free AACR Whitepaper) journal Molecular Cancer Therapeutics.

(Press release, Whitehawk Therapeutics, OCT 24, 2025, View Source [SID1234656992])

On October 24, 2025 Merus N.V. (Nasdaq: MRUS) (Merus, the Company, we, or our), an oncology company developing innovative, full-length multispecific antibodies and antibody drug conjugates (Biclonics, Triclonics and ADClonics), reported interim clinical data as of a July 29, 2025 data cutoff from the ongoing phase 2 trial of the bispecific antibody petosemtamab in combination with standard of care FOLFOX/FOLFIRI in 1L and 2L metastatic colorectal cancer (mCRC), and petosemtamab monotherapy in 3L+ mCRC. These data will be presented in a plenary session oral presentation by Dr. Moh’d Khushman M.D., Washington University School of Medicine, St. Louis, MO, at the AACR (Free AACR Whitepaper)-NCI-EORTC AACR-NCI-EORTC (Free AACR-NCI-EORTC Whitepaper) International Conference on Molecular Targets and Cancer Therapeutics (EORTC-NCI-AACR) (Free ASGCT Whitepaper) (Free EORTC-NCI-AACR Whitepaper) on Friday, October 24 at 10:20 a.m. ET.

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"Petosemtamab’s unique mechanism of action, including targeting both EGFR and LGR5, and potential to safely combine with FOLFOX/FOLFIRI, represents an important finding for patients with EGFR inhibitor-naïve metastatic colorectal cancer," said Fabian Zohren, M.D., Ph.D., Chief Medical Officer of Merus. "These data demonstrate petosemtamab’s clinical activity beyond head and neck squamous cell carcinoma. We are encouraged that petosemtamab has the potential to become a transformational treatment and new standard of care for patients across a range of solid tumors."

"Metastatic colorectal cancer remains a formidable challenge with limited effective therapies. The promising early results with petosemtamab offer hope for advancing care and bringing new treatment possibilities to patients facing this difficult disease," added Dr. Khushman.

Petosemtamab (MCLA-158: EGFR x LGR5 Biclonics)

Presentation title: Petosemtamab (MCLA-158) monotherapy or with chemotherapy in metastatic colorectal cancer: Preliminary antitumor activity and safety data from a phase 2 trial
Observations in the presentation include:
As of a July 29, 2025 data cutoff date:

54 patients (pts) with left- and/or right-sided, KRAS, NRAS, and BRAF wildtype microsatellite stable mCRC received petosemtamab 1500 mg every two weeks, in combination with FOLFOX/FOLFIRI or as monotherapy
Pts treated in 1L or 2L had no prior anti-EGFR therapy
Pts treated in 2L received 1 prior chemotherapy regimen in the metastatic setting
Pts treated in 3L+ received at least 2 prior regimens in the metastatic setting, including a prior anti-EGFR therapy
Efficacy evaluable population consisted of patients with ≥1 dose of petosemtamab who had opportunity for ≥8 weeks follow up and ≥1 post baseline tumor assessment or discontinued petosemtamab early due to disease progression, symptomatic deterioration and/or death
1L petosemtamab with FOLFOX/FOLFIRI
14 pts were treated in 1L (10 FOLFOX and 4 FOLFIRI)
10 pts were efficacy evaluable, 8 left-sided; 10 (100%) remained on treatment
80% (8 of 10) response rate: 1 confirmed complete response, 7 partial responses (PRs) (4 unconfirmed of which 1 confirmed post data cutoff); 2 stable diseases (SDs)
88% (7 of 8) response rate in left-sided: 1 confirmed complete response, 6 PRs (3 unconfirmed, 1 unconfirmed response confirmed post data cutoff); 1 SD
One SD observed to be an unconfirmed PR post data cutoff leading to 100% (8/8) response rate left-sided and 90% (9/10) response rate overall in 1L
All unconfirmed PRs remained on treatment without disease progression
2L petosemtamab with FOLFOX/FOLFIRI
14 pts were treated in 2L (2 FOLFOX and 12 FOLFIRI)
13 were efficacy evaluable; 10 (77%) remained on treatment
62% response rate: 8 PRs (3 unconfirmed of which 1 confirmed post data cutoff); 4 SDs and 1 clinical deterioration prior to first scan
All unconfirmed PRs and SDs remained on treatment without disease progression
3L+ petosemtamab monotherapy:
26 pts were treated
20 were efficacy evaluable, 6 (30%) remained on treatment
10% confirmed response rate: 2 PRs; 9 SDs (5 remained on treatment)
Safety:
Petosemtamab safety profile in mCRC observed thus far, appears consistent with its established safety profile in recurrent/metastatic head and neck squamous cell carcinoma
No significant overlapping toxicities identified in combination with FOLFOX/FOLFIRI
No new safety signals identified
Infusion related reactions (IRRs) were managed with premedication and prolonged infusion on cycle 1 day 1; no discontinuations due to IRRs
Presentation:
Title: Petosemtamab (MCLA-158) monotherapy or with chemotherapy in metastatic colorectal cancer: Preliminary antitumor activity and safety data from a phase 2 trial
Session Title: Plenary Session 4: Clinical Trials Plenary Session
Date and Time: Friday, October 24, 10:20 a.m. ET
The same data will also be available in a poster:
Session Title: Poster Session B
Session Date and Time: Friday, October 24, 12:30-4:00 p.m. ET

As full presentations become available at the conference, they will contemporaneously be available on the Merus website.

(Press release, Merus, OCT 24, 2025, View Source [SID1234656991])