On August 25, 2025 Molecular Partners AG (SIX: MOLN; NASDAQ: MOLN), a clinical-stage biotech company developing a new class of custom-built protein drugs known as DARPin therapeutics ("Molecular Partners" or the "Company"), reported corporate highlights and unaudited financial results for the first half of 2025 (Press release, Molecular Partners, AUG 25, 2025, View Source [SID1234655462]).

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"Molecular Partners continues to make good progress towards key development milestones, notably in our two clinical programs. Following the expansion of our strategic radiotherapy partnership with Orano Med in January, we are advancing our lead program MP0712 towards its first-in-human trial. With the data package complete, we anticipate the IND filing and Phase 1 initiation in 2025, and initial clinical data in H1 2026. Our multispecific T cell engager MP0533 is making progress in its Phase 1/2a trial for acute myeloid leukemia. Recently presented data show both increased response rates and greater depth of responses and we look forward to presenting the first data under the amended study protocol in Q4 2025. We also strengthened our leadership with the appointment of Martin Steegmaier, Ph.D., as CSO, further underlining our commitment to delivering improved treatment options for patients and significant value for our stakeholders. Our finances remain robust with funding projected into 2028," said Patrick Amstutz, Ph.D., CEO of Molecular Partners.

Research & Development Highlights

MP0533 (Multispecific T Cell Engager; CD33 x CD123 x CD70 x CD3)

MP0533 is currently being evaluated in a Phase 1/2a clinical trial for relapsed/refractory acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS)/AML (ClinicalTrials.gov: NCT05673057). Molecular Partners presented updated data from the study at the 30th Annual European Hematology Association (EHA) (Free EHA Whitepaper) Congress in June, outlining the impact of accelerated step-up dosing regimen of MP0533 on exposure and clinical responses in cohort 8, providing the rationale for further optimization to the dosing regimen implemented in the ongoing cohort 9. Initial data from cohort 8 show promising antitumor activity: 3 of 8 (>30%) evaluable patients with relapsed/refractory disease achieved a clinical response after the first cycle, with one complete response and two complete responses with partial hematologic recovery. Notably, two patients maintained their responses for over three months, including one patient still responding after more than six months at data cutoff (14 April 2025) and still on treatment today. This cohort benefited from a higher starting dose and a faster step-up dosing schedule, leading to prolonged exposure within the predicted therapeutic range and notable blast reduction in most patients, with an acceptable safety profile after dose adjustments in cohort 8.

Encouraged by these results, Molecular Partners amended the study protocol for cohorts 9 and 10 by further accelerating the step-up dosing, increasing the dosing frequency and introducing anti-CD20 premedication for greater cumulative exposure. These changes aim to enhance both the depth and duration of patient responses. Cohort 9 is exploring a lower target dose than cohort 8 to assess the safety of up to daily dosing for the first 14 days of treatment, leading to significantly denser dosing; cohort 10 aims at reaching the same target dose as cohort 8 while exposing patients to more drug over time. Initiation of cohort 10 is anticipated to start in the coming weeks, pending appropriate approvals. Cohort 9 is now fully recruited, with initial data expected to be presented in Q4 2025.
MP0533 continues to show broad activity, with initial blast reductions in a majority of patients treated. The data continue to indicate that the patients more likely to see durable responses will be those who initiate therapy with a lower level of blasts at baseline. Looking forward, Molecular Partners plans to explore future cohorts of MP0533 in combination settings, both in relapsed/refractory as well as in front-line patients, should favorable antitumor activity continue to be observed. The company is engaging with regulators such as the U.S. Food and Drug Administration (FDA) to discuss next steps.

MP0712 (212Pb x DLL3), Radio-DARPin Pipeline and Global Partnership with Orano Med

The Phase 1 Investigational New Drug (IND) application for MP0712, a 212Pb-based Radio-DARPin therapy (RDT) candidate targeting the tumor-associated protein delta-like ligand 3 (DLL3), co-developed with Orano Med for the treatment of small cell lung cancer (SCLC), is in preparation. Molecular Partners presented preclinical data in April at the American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting 2025, showing a high tumor uptake and a favorable safety profile for MP0712, with good efficacy in mouse models matching clinically relevant DLL3 expression levels. Dialogue with the FDA is ongoing and IND filing expected in Q3 2025. The first clinical sites in the U.S. are identified and, pending regulatory clearance, patient dosing is planned to initiate in 2025 with initial first-in-human clinical data expected in H1 2026.

In H1 2025, Molecular Partners accepted a request from Nuclear Medicine Research Infrastructure (NuMeRI) in South Africa to provide MP0712 for imaging use under the legal framework in South Africa for compassionate care (also referred to as Section 21 of the Medicines and Related Substances Act). This approach allows for the potential to generate initial images applying MP0712 labelled with 203Pb in patients with SCLC and other DLL3-expressing neuroendocrine cancers. While the decision of where and how to share data from the image work under Section 21 remains at the discretion of NuMeRI, the Company anticipates providing an update on MP0712 in H2 2025. 203Pb and 212Pb are an element-equivalent pair of lead (Pb) isotopes, with 203Pb primarily used for imaging and 212Pb for therapeutic applications (targeted alpha therapy, TAT). As a "matched pair", pre-treatment imaging with 203Pb will provide a prediction of treatment behavior with 212Pb.

The second RDT program co-developed with Orano Med is MP0726, targeting mesothelin (MSLN), a tumor target overexpressed across several cancers with high unmet need, such as ovarian cancer. The development of therapeutics against MSLN has been hampered by high levels of shed MSLN. Leveraging the unique properties of DARPins, Molecular Partners has developed Radio-DARPins able to selectively bind to membrane-bound MSLN without being impacted by shed MSLN. The Company presented preclinical data on MP0726 at AACR (Free AACR Whitepaper) 2025 in April and at the 2025 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) in June. Initial clinical data are expected in 2026.

In January 2025, Molecular Partners and Orano Med further expanded their agreement to co-develop up to ten radiotherapy programs. In addition to its world class expertise and capabilities in the development of TAT with 212Pb, Orano Med will ensure the production of the 212Pb-based Radio-DARPins for clinical trials and commercialization. Orano Med possesses virtually unlimited source material for 212Pb production and has established robust and independent supply and manufacturing capabilities required for the seamless delivery of TAT to clinical sites internationally.
Switch-DARPins (Next-Generation Immune Cell Engagers)

By employing a multi-specific Switch-DARPin, Molecular Partners aims to increase the safety and potency of T cell engagers (TCEs). Preclinical proof-of-concept in a solid tumor model for a novel CD3 Switch-DARPin TCE with CD2 costimulation was presented at AACR (Free AACR Whitepaper) in April 2025. The data show the feasibility of conditional T cell activation with potent co-stimulation in solid tumors, but not in healthy tissues. In addition, data showed that the CD3 Switch-DARPin activates T cells specifically in the presence of cells co-expressing the tumor targets MSLN and EpCAM, increasing tumor specificity. The Company will present an update on the CD3 Switch-DARPin program at the Annual Meeting of the Society for Immunotherapy of Cancer (SITC) (Free SITC Whitepaper) in Q4 2025.

MP0317 (tumor-localized CD40 agonist)

Molecular Partners presented comprehensive biomarker analyses from the completed Phase 1 dose escalation trial of the localized CD40 agonist MP0317 in solid tumors at SITC (Free SITC Whitepaper) in November 2024. MP0317 is designed to activate immune cells specifically within the tumor microenvironment by anchoring to fibroblast activation protein (FAP), which is expressed in high amounts in the stroma of various solid tumors. The Company believes this tumor-localized approach has the potential to deliver greater efficacy with fewer side effects compared to systemic CD40-targeting therapies.

Molecular Partners has committed to supporting an investigator-initiated trial of MP0317. The study is being designed for the treatment of patients with advanced cholangiocarcinoma in combination with standard-of-care. A study protocol has been submitted; pending regulatory approval, the study could be initiated in 2025.

Corporate Governance Highlights

As announced on August 21, 2025, Molecular Partners appointed Martin Steegmaier, Ph.D., as Chief Scientific Officer (CSO) and member of its Executive Committee, effective October 1, 2025. He brings a wealth of experience in oncology drug development, having previously contributed to the advancement of several innovative cancer therapies at major biotech and pharmaceutical companies.

In H1 2025, Molecular Partners undertook a strategic review of its operations and headcount, with the objectives of increased efficiency in the organization and to sharpen the focus on advancing its clinical assets. As a result of this review, the Company informed the Amt für Wirtschaft of Kanton Zürich (Office for Economic Affairs) in June 2025 of its intention to reduce its current workforce by no more than 40 positions, representing up to ~24% of all positions. All employees affected have been informed, and based upon these headcount reductions, the Company now anticipates its cash runway to extend into 2028, beyond its prior guidance of 2027.

All motions proposed by the Board of Directors at the Annual General Meeting, held in April 2025, were approved by the shareholders of the Company by a wide majority.

Financial and Business Outlook
For the full year 2025, at constant exchange rates, the Company expects total operating expenses of CHF 55-65 million of which around CHF 7 million will be non-cash effective costs for share-based payments, IFRS pension accounting and depreciation.

The Company’s cash and cash equivalents and short-term time deposits were CHF 114 million as of June 30, 2025 and based on current operating assumptions, will be sufficient to fund its operating expenses and capital expenditure requirements into 2028.

On August 25, 2025 Daiichi Sankyo reported that DATROWAY (datopotamab deruxtecan) has been approved in China for the treatment of adult patients with unresectable or metastatic hormone receptor (HR) positive, HER2 negative (IHC 0, IHC 1+ or IHC 2+/ISH-) breast cancer who have received prior endocrine therapy and at least one line of chemotherapy in the advanced setting (Press release, Daiichi Sankyo, AUG 25, 2025, View Source [SID1234655446]).

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DATROWAY is a specifically engineered TROP2 directed DXd antibody drug conjugate (ADC) discovered by Daiichi Sankyo (TSE: 4568) and being jointly developed and commercialized by Daiichi Sankyo and AstraZeneca (LSE/STO/Nasdaq: AZN).

Breast cancer is the second most common cancer in women in China. 1 Approximately 357,000 cases of breast cancer were diagnosed in China in 2022, with nearly 75,000 deaths.1 It is estimated that 70% of diagnosed cases are considered what has been historically called HR positive, HER2 negative breast cancer (measured as HER2 score of IHC 0, IHC 1+ or IHC 2+/ISH-).

The approval of DATROWAY by China’s National Medical Products Administration (NMPA) is based on results from the TROPION-Breast01 phase 3 trial. In the trial, DATROWAY significantly reduced the risk of disease progression or death by 37% compared to investigator’s choice of chemotherapy (hazard ratio [HR]=0.63; 95% confidence interval [CI]: 0.52-0.76; p<0.0001) in patients with HR positive, HER2 negative metastatic breast cancer as assessed by blinded independent central review (BICR). Median progression free survival (PFS) was 6.9 months in patients treated with DATROWAY versus 4.9 months with chemotherapy. A confirmed objective response rate (ORR) of 36% was observed in the DATROWAY arm compared to an ORR of 23% observed in the chemotherapy arm. There were two (0.5%) complete responses (CRs) and 131 partial responses (PRs) (36%) seen in the DATROWAY arm compared to zero (0%) CRs and 84 (23%) PRs in the chemotherapy arm. The median duration of response (DoR) was 6.7 months (95% CI: 5.6-9.8) in the DATROWAY arm compared to 5.7 months (95% CI: 4.9-6.8) in the chemotherapy arm. The final overall survival (OS) results of the trial did not achieve statistical significance (HR 1.01; 95% CI: 0.83-1.22). In an exploratory sensitivity analysis, OSadjusted for subsequent ADC treatment was 19.1 months in the DATROWAY arm versus 17.5 months in the chemotherapy arm (HR 0.86; 95% CI: 0.70-1.06).

In an exploratory analysis of the 83 patients enrolled in TROPION-Breast01 in China, median PFS was 8.1 months in patients treated with DATROWAY versus 4.2 months with chemotherapy (HR 0.54; 95% CI: 0.30-0.96) and a confirmed ORR of 38.6% was observed in the DATROWAY arm compared to an ORR of 17.9% in the chemotherapy arm.

"Despite the progress we have made in managing HR positive, HER2 negative metastatic breast cancer, many patients still face limited options once their disease progresses after endocrine therapy and chemotherapy," said Professor Binghe Xu, Director of Clinical Trial Center (GCP) of National Cancer Center, Cancer Hospital Chinese Academy of Medical Sciences, and China leading PI of TROPIONBreast01. "The approval of datopotamab deruxtecan, a novel TROP2 directed antibody drug conjugate, represents a meaningful step forward in expanding therapeutic choices for patients with breast cancer."

"The approval of DATROWAY provides a new treatment option for patients with metastatic HR positive, HER2 negative breast cancer, enabling timely access to an innovative TROP2 targeted antibody drug conjugate in China," said Michio Hayashi, China President, Daiichi Sankyo. "DATROWAY is now the second DXd antibody drug conjugate approved in China following ENHERTU and expands our portfolio to meet the evolving treatment needs of patients with a range of breast cancer subtypes."

"Despite considerable advancements in the treatment of HR positive breast cancer, new medicines are still needed to tackle the frequent and complex challenge of disease progression following initial therapies," said Dave Fredrickson, Executive Vice President, Oncology Hematology Business Unit, AstraZeneca. "We are proud to bring DATROWAY to patients in China for the first time, offering those with metastatic HR positive, HER2 negative breast cancer a new and needed option."

In TROPION-Breast01, the most common (≥20%) adverse reactions, including laboratory abnormalities were stomatitis, nausea, fatigue, decreased leukocytes, decreased calcium, alopecia, decreased lymphocytes, decreased hemoglobin, constipation, decreased neutrophils, dry eye, vomiting, increased ALT, keratitis, increased AST and increased alkaline phosphatase. Grade 3 or higher adverse reactions in patients (>0.5%) receiving DATROWAY were urinary tract infection (1.9%), COVID-19 infection (1.7%), interstitial lung disease (ILD)/pneumonitis (1.1%), acute kidney injury (0.6%), pulmonary embolism (0.6%), vomiting (0.6%), diarrhea (0.6%), hemiparesis (0.6%) and anemia (0.6%). A grade 5 adverse reaction occurred in one patient (0.3%) and was attributed to ILD/pneumonitis.

About TROPION-Breast01

TROPION-Breast01 is a global, randomized, multicenter, open-label phase 3 trial evaluating the efficacy and safety of intravenous DATROWAY (6 mg/kg) once per 21-day cycle versus investigator’s choice of single-agent chemotherapy (eribulin, capecitabine, vinorelbine or gemcitabine) in adult patients with unresectable or metastatic HR positive, HER2 negative (IHC 0, IHC 1+ or IHC 2+/ISH-) breast cancer who have progressed on and are not suitable for endocrine therapy per investigator assessment and have received at least one prior line of chemotherapy for unresectable or metastatic disease.

Following disease progression or discontinuation of DATROWAY or chemotherapy, patients had the option to receive a subsequent treatment at the discretion of their physician. Crossover between trial arms was not permitted.

The dual primary endpoints of TROPION-Breast01 are PFS as assessed by BICR and OS. Key secondary endpoints include ORR, DoR, investigator-assessed PFS, disease control rate, time to first subsequent therapy and safety. The PFS data and additional results for key secondary endpoints of TROPIONBreast01 were published in the Journal of Clinical Oncology and OS results were presented at a Virtual Plenary session hosted by the European Society for Medical Oncology in February 2025.

TROPION-Breast01 enrolled 732 patients in Africa, Asia, Europe, North America and South America. For more information visit ClinicalTrials.gov.

About Hormone Receptor Positive, HER2 Negative Breast Cancer

Breast cancer is the second most common cancer and one of the leading causes of cancer-related deaths worldwide.5 More than two million breast cancer cases were diagnosed in 2022 with more than 665,000 deaths globally.5 While survival rates are high for those diagnosed with early breast cancer, only about 30% of patients diagnosed with or progress to metastatic disease are expected to live five years following diagnosis.2 Approximately 357,000 cases of breast cancer are diagnosed annually in China, representing the most cases diagnosed anywhere in the world, and of these about 20% are diagnosed in the advanced or metastatic setting.

Approximately 70% of diagnosed cases are considered what has been historically called HR positive, HER2 negative breast cancer (measured as HER2 score of IHC 0, IHC 1+ or IHC 2+/ISH-).2 Endocrine therapy is widely given consecutively in the early lines of treatment for metastatic HR positive breast cancer.7 However, after initial treatment, further efficacy from endocrine therapy is often limited.

About DATROWAY

DATROWAY (datopotamab deruxtecan; datopotamab deruxtecan-dlnk in the U.S. only) is a TROP2 directed ADC. Designed using Daiichi Sankyo’s proprietary DXd ADC Technology, DATROWAY is one of six DXd ADCs in the oncology pipeline of Daiichi Sankyo, and one of the most advanced programs in AstraZeneca’s ADC scientific platform. DATROWAY is comprised of a humanized antiTROP2 IgG1 monoclonal antibody, developed in collaboration with Sapporo Medical University, attached to a number of topoisomerase I inhibitor payloads (an exatecan derivative, DXd) via tetrapeptide-based cleavable linkers.

DATROWAY (6 mg/kg) is approved in more than 35 countries worldwide for the treatment of adult patients with unresectable or metastatic HR positive, HER2 negative (IHC 0, IHC 1+ or IHC 2+/ISH-) breast cancer who have received prior endocrine-based therapy and chemotherapy for unresectable or metastatic disease based on the results from the TROPION-Breast01 trial.

DATROWAY (6 mg/kg) is approved in Russia and the U.S. for the treatment of adult patients with locally advanced or metastatic EGFR-mutated non-small cell lung cancer (NSCLC) who have received prior EGFR-directed therapy and platinum-based chemotherapy based on the results from the TROPIONLung05 and TROPION-Lung01 trials. Continued approval for this indication in the U.S. may be contingent upon verification and description of clinical benefit in the confirmatory trial.

About the DATROWAY Clinical Development Program

A comprehensive global clinical development program is underway with more than 20 trials evaluating the efficacy and safety of DATROWAY across multiple cancers, including NSCLC, triple negative breast cancer and HR positive, HER2 negative breast cancer. The program includes eight phase 3 trials in lung cancer and five phase 3 trials in breast cancer evaluating DATROWAY as a monotherapy and in combination with other cancer medicines in various settings.

On August 25, 2025 PDS Biotechnology presented its corporate presentation (Presentation, PDS Biotechnology, AUG 25, 2025, View Source [SID1234655463]).

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On August 25, 2025 Daiichi Sankyo reported that DATROWAY (datopotamab deruxtecan) has been approved in China for the treatment of adult patients with unresectable or metastatic hormone receptor (HR) positive, HER2 negative (IHC 0, IHC 1+ or IHC 2+/ISH-) breast cancer who have received prior endocrine therapy and at least one line of chemotherapy in the advanced setting (Press release, Daiichi Sankyo, AUG 25, 2025, View Source [SID1234655446]).

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

DATROWAY is a specifically engineered TROP2 directed DXd antibody drug conjugate (ADC) discovered by Daiichi Sankyo (TSE: 4568) and being jointly developed and commercialized by Daiichi Sankyo and AstraZeneca (LSE/STO/Nasdaq: AZN).

Breast cancer is the second most common cancer in women in China. 1 Approximately 357,000 cases of breast cancer were diagnosed in China in 2022, with nearly 75,000 deaths.1 It is estimated that 70% of diagnosed cases are considered what has been historically called HR positive, HER2 negative breast cancer (measured as HER2 score of IHC 0, IHC 1+ or IHC 2+/ISH-).

The approval of DATROWAY by China’s National Medical Products Administration (NMPA) is based on results from the TROPION-Breast01 phase 3 trial. In the trial, DATROWAY significantly reduced the risk of disease progression or death by 37% compared to investigator’s choice of chemotherapy (hazard ratio [HR]=0.63; 95% confidence interval [CI]: 0.52-0.76; p<0.0001) in patients with HR positive, HER2 negative metastatic breast cancer as assessed by blinded independent central review (BICR). Median progression free survival (PFS) was 6.9 months in patients treated with DATROWAY versus 4.9 months with chemotherapy. A confirmed objective response rate (ORR) of 36% was observed in the DATROWAY arm compared to an ORR of 23% observed in the chemotherapy arm. There were two (0.5%) complete responses (CRs) and 131 partial responses (PRs) (36%) seen in the DATROWAY arm compared to zero (0%) CRs and 84 (23%) PRs in the chemotherapy arm. The median duration of response (DoR) was 6.7 months (95% CI: 5.6-9.8) in the DATROWAY arm compared to 5.7 months (95% CI: 4.9-6.8) in the chemotherapy arm. The final overall survival (OS) results of the trial did not achieve statistical significance (HR 1.01; 95% CI: 0.83-1.22). In an exploratory sensitivity analysis, OSadjusted for subsequent ADC treatment was 19.1 months in the DATROWAY arm versus 17.5 months in the chemotherapy arm (HR 0.86; 95% CI: 0.70-1.06).

In an exploratory analysis of the 83 patients enrolled in TROPION-Breast01 in China, median PFS was 8.1 months in patients treated with DATROWAY versus 4.2 months with chemotherapy (HR 0.54; 95% CI: 0.30-0.96) and a confirmed ORR of 38.6% was observed in the DATROWAY arm compared to an ORR of 17.9% in the chemotherapy arm.

"Despite the progress we have made in managing HR positive, HER2 negative metastatic breast cancer, many patients still face limited options once their disease progresses after endocrine therapy and chemotherapy," said Professor Binghe Xu, Director of Clinical Trial Center (GCP) of National Cancer Center, Cancer Hospital Chinese Academy of Medical Sciences, and China leading PI of TROPIONBreast01. "The approval of datopotamab deruxtecan, a novel TROP2 directed antibody drug conjugate, represents a meaningful step forward in expanding therapeutic choices for patients with breast cancer."

"The approval of DATROWAY provides a new treatment option for patients with metastatic HR positive, HER2 negative breast cancer, enabling timely access to an innovative TROP2 targeted antibody drug conjugate in China," said Michio Hayashi, China President, Daiichi Sankyo. "DATROWAY is now the second DXd antibody drug conjugate approved in China following ENHERTU and expands our portfolio to meet the evolving treatment needs of patients with a range of breast cancer subtypes."

"Despite considerable advancements in the treatment of HR positive breast cancer, new medicines are still needed to tackle the frequent and complex challenge of disease progression following initial therapies," said Dave Fredrickson, Executive Vice President, Oncology Hematology Business Unit, AstraZeneca. "We are proud to bring DATROWAY to patients in China for the first time, offering those with metastatic HR positive, HER2 negative breast cancer a new and needed option."

In TROPION-Breast01, the most common (≥20%) adverse reactions, including laboratory abnormalities were stomatitis, nausea, fatigue, decreased leukocytes, decreased calcium, alopecia, decreased lymphocytes, decreased hemoglobin, constipation, decreased neutrophils, dry eye, vomiting, increased ALT, keratitis, increased AST and increased alkaline phosphatase. Grade 3 or higher adverse reactions in patients (>0.5%) receiving DATROWAY were urinary tract infection (1.9%), COVID-19 infection (1.7%), interstitial lung disease (ILD)/pneumonitis (1.1%), acute kidney injury (0.6%), pulmonary embolism (0.6%), vomiting (0.6%), diarrhea (0.6%), hemiparesis (0.6%) and anemia (0.6%). A grade 5 adverse reaction occurred in one patient (0.3%) and was attributed to ILD/pneumonitis.

About TROPION-Breast01

TROPION-Breast01 is a global, randomized, multicenter, open-label phase 3 trial evaluating the efficacy and safety of intravenous DATROWAY (6 mg/kg) once per 21-day cycle versus investigator’s choice of single-agent chemotherapy (eribulin, capecitabine, vinorelbine or gemcitabine) in adult patients with unresectable or metastatic HR positive, HER2 negative (IHC 0, IHC 1+ or IHC 2+/ISH-) breast cancer who have progressed on and are not suitable for endocrine therapy per investigator assessment and have received at least one prior line of chemotherapy for unresectable or metastatic disease.

Following disease progression or discontinuation of DATROWAY or chemotherapy, patients had the option to receive a subsequent treatment at the discretion of their physician. Crossover between trial arms was not permitted.

The dual primary endpoints of TROPION-Breast01 are PFS as assessed by BICR and OS. Key secondary endpoints include ORR, DoR, investigator-assessed PFS, disease control rate, time to first subsequent therapy and safety. The PFS data and additional results for key secondary endpoints of TROPIONBreast01 were published in the Journal of Clinical Oncology and OS results were presented at a Virtual Plenary session hosted by the European Society for Medical Oncology in February 2025.

TROPION-Breast01 enrolled 732 patients in Africa, Asia, Europe, North America and South America. For more information visit ClinicalTrials.gov.

About Hormone Receptor Positive, HER2 Negative Breast Cancer

Breast cancer is the second most common cancer and one of the leading causes of cancer-related deaths worldwide.5 More than two million breast cancer cases were diagnosed in 2022 with more than 665,000 deaths globally.5 While survival rates are high for those diagnosed with early breast cancer, only about 30% of patients diagnosed with or progress to metastatic disease are expected to live five years following diagnosis.2 Approximately 357,000 cases of breast cancer are diagnosed annually in China, representing the most cases diagnosed anywhere in the world, and of these about 20% are diagnosed in the advanced or metastatic setting.

Approximately 70% of diagnosed cases are considered what has been historically called HR positive, HER2 negative breast cancer (measured as HER2 score of IHC 0, IHC 1+ or IHC 2+/ISH-).2 Endocrine therapy is widely given consecutively in the early lines of treatment for metastatic HR positive breast cancer.7 However, after initial treatment, further efficacy from endocrine therapy is often limited.

About DATROWAY

DATROWAY (datopotamab deruxtecan; datopotamab deruxtecan-dlnk in the U.S. only) is a TROP2 directed ADC. Designed using Daiichi Sankyo’s proprietary DXd ADC Technology, DATROWAY is one of six DXd ADCs in the oncology pipeline of Daiichi Sankyo, and one of the most advanced programs in AstraZeneca’s ADC scientific platform. DATROWAY is comprised of a humanized antiTROP2 IgG1 monoclonal antibody, developed in collaboration with Sapporo Medical University, attached to a number of topoisomerase I inhibitor payloads (an exatecan derivative, DXd) via tetrapeptide-based cleavable linkers.

DATROWAY (6 mg/kg) is approved in more than 35 countries worldwide for the treatment of adult patients with unresectable or metastatic HR positive, HER2 negative (IHC 0, IHC 1+ or IHC 2+/ISH-) breast cancer who have received prior endocrine-based therapy and chemotherapy for unresectable or metastatic disease based on the results from the TROPION-Breast01 trial.

DATROWAY (6 mg/kg) is approved in Russia and the U.S. for the treatment of adult patients with locally advanced or metastatic EGFR-mutated non-small cell lung cancer (NSCLC) who have received prior EGFR-directed therapy and platinum-based chemotherapy based on the results from the TROPIONLung05 and TROPION-Lung01 trials. Continued approval for this indication in the U.S. may be contingent upon verification and description of clinical benefit in the confirmatory trial.

About the DATROWAY Clinical Development Program

A comprehensive global clinical development program is underway with more than 20 trials evaluating the efficacy and safety of DATROWAY across multiple cancers, including NSCLC, triple negative breast cancer and HR positive, HER2 negative breast cancer. The program includes eight phase 3 trials in lung cancer and five phase 3 trials in breast cancer evaluating DATROWAY as a monotherapy and in combination with other cancer medicines in various settings.

On August 25, 2025 Quest Diagnostics (NYSE: DGX), a leading provider of diagnostic information services, reported that the U.S. Food and Drug Administration (FDA) has granted Breakthrough Device Designation for the company’s Haystack MRD test for identifying MRD-positive patients with stage II colorectal cancer following curative-intent surgical treatment who may benefit from adjuvant therapy in accordance with therapeutic product labeling (Press release, Quest Diagnostics, AUG 25, 2025, View Source [SID1234655464]).

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The new designation adds to growing evidence of the value of the Haystack MRD test for both clinical and pharmaceutical applications. It also aligns with a robust body of research supporting the potential of ctDNA-based MRD tests to detect residual or recurrent cancer from solid tumors. Quest introduced a clinical laboratory-developed test version of Haystack MRD in late 2024 and is broadening access for oncologists and pharmaceutical partners.

"We are committed to working with the FDA and our research partners to validate the use of Haystack MRD in a variety of solid tumors, building on this first designation for an early-stage colorectal cancer," said Dan Edelstein, Vice President and General Manager, Haystack Oncology. "Our goal is to deliver highly accurate, personalized monitoring of treatment response and recurrence to more patients, both in clinical care and in pharmaceutical trials, and this Breakthrough Designation brings us closer to our goal."

The Breakthrough Devices Program applies to certain medical devices and device-led combination products that provide for more effective treatment or diagnosis of life-threatening or irreversibly debilitating diseases or conditions. It is intended to provide patients and healthcare providers with timely access to medical devices by speeding up development, assessment, and review for premarket approval, 510(k) clearance, and De Novo marketing authorization, after undergoing the FDA’s rigorous standards for device safety and effectiveness.

About ctDNA MRD

A growing body of research underscores the value of ctDNA MRD tests for identifying residual or recurring cancer in solid tumors. By detecting trace amounts of tumor-derived DNA in the bloodstream, ctDNA MRD testing can reveal molecular evidence of disease recurrence months before it becomes apparent through imaging or other conventional monitoring methods. This early insight can help clinicians tailor surveillance strategies, adjust treatment plans, and potentially intervene before disease progression becomes clinically evident. Nearly all oncologists (96%) in a recent survey1 by Harris Poll for Quest Diagnostics said MRD testing has the potential to identify cancer recurrence earlier than other current methods.

About Haystack MRD

Haystack MRD is a highly sensitive and specific liquid biopsy test designed by cancer genomic pioneers and liquid biopsy experts to uncover low levels of circulating-tumor DNA (ctDNA)—tiny fragments of DNA in the bloodstream that originate from tumor cancer cells that can signify residual, recurrent, or resistant disease in patients diagnosed with cancer. Used in multiple clinical trials and research studies with top institutions in the U.S., Canada, and Australia, and by clinicians at over 75 top cancer and academic centers and health systems, Haystack MRD is now available for clinical use as part of the leading oncology testing portfolio of Quest Diagnostics. Haystack MRD is also available for clinical trials as an investigational device by Haystack Oncology in laboratories located in Baltimore, Maryland; Hamburg, Germany; and Helsinki, Finland. For more information, visit www.haystackmrd.com.