On September 16, 2026 Nona Biosciences ("Nona"), a global biotechnology company advancing biologics discovery and development through innovativetechnology platforms, reported the development of HCAbLM, the world’s first language model specifically trained on fully human heavy-chain-only antibodies (HCAbs). HCAbLM was built on a large-scale repertoire comprising 31.8 million fully human HCAb sequences from 73 independently immunized HCAb transgenic mice. The study, "A foundation model learns the sequence and functional grammar of fully human heavy-chain-only antibodies," was published in bioRxiv.

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From Binder to Drug Candidate: A Leap in AI Antibody Development

The main bottleneck in the current AI antibody field is no longer "whether an antibody that binds the target can be designed," but rather "whether the designed antibody can be manufactured at scale, whether it will aggregate, and whether it is stable"—that is, developability. HCAbLM was created precisely to address this issue. The model has learned the "sequence gramma" unique to fully human HCAbs—a set of underlying rules that determine whether an antibody can fold, exist stably, and ultimately become a drug. Conventional general-purpose models cannot capture this set of rules because their training data contain almost no HCAb sequences. HCAbLM fully demonstrates that a dedicated model trained on unique antibody sequence data can better translate "sequence space cognition" into "developability prediction."

A Dedicated HCAb Model Outperforms General-Purpose Protein and Antibody Models

The representations learned by HCAbLM demonstrate transferability to experimentally measured antibody properties, including size exclusion chromatography (SEC) purity, hydrophobic interaction chromatography (HIC) behavior, and thermal stability, highlighting HCAbLM’s potential in the evaluation and optimization of fully human HCAbs, going beyond mere sequence analysis.

In public benchmarks for cross-project developability prediction, HCAbLM, with only 366 million parameters, surpassed general-purpose protein large models including Meta’s ESM-6B with 6 billion parameters, as well as previously leading antibody language models IgLM and AbLang, on two core metrics: SEC purity and HIC behavior.

The development of HCAbLM marks an important advancement in Nona’s application of artificial intelligence (AI) to antibody discovery and development. By combining large-scale antibody repertoires with AI-driven modeling, Nona is building a foundation for more efficient and data-driven antibody design and developability assessment.

"The development of HCAbLM represents an important step in our efforts to apply AI to specialized antibody formats and unlock the value of large-scale antibody repertoires," said Dr. Di Hong, Chief Executive Officer of Nona Biosciences. "By learning the unique sequence characteristics of fully human HCAbs and demonstrating transferability to experimentally measured molecular properties, HCAbLM provides a new foundation for AI-enabled antibody discovery and development. We look forward to further integrating HCAbLM with Nona’s technology platforms, and leveraging these capabilities to accelerate antibody discovery and development while empowering our partners to unlock new opportunities for next-generation biotherapeutics."

(Press release, Nona Biosciences, SEP 16, 2026, View Source [SID1234670896])

On September 16, 2026 Circle Pharma, Inc., a clinical-stage biopharmaceutical company pioneering next-generation targeted macrocycle therapeutics for cancer, reported an oversubscribed $92.5 million Series E financing. The financing was led by The Column Group and included participation from other existing and new investors including Nextech Invest, RA Capital Management, Euclidean Capital and Eli Lilly and Company. Proceeds from the financing will drive the advancement of CID-165, a first-in-class oral macrocyclic cyclin D1 RxL inhibitor, through early clinical development for ER-positive breast cancer, while also supporting the continued development of Circle Pharma’s broader pipeline of cyclin-targeted macrocycles.

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"This financing marks a significant milestone as we execute upon our vision of harnessing the power of macrocycles to transform the treatment of cancer," said David J. Earp, J.D., Ph.D., president and chief executive officer of Circle Pharma. "Momentum around our cyclin D1 program has continued to build as CID-165 advances toward the clinic. We believe CID-165 has the potential to become a new backbone therapy for ER-positive breast cancer and this financing provides us with the resources to generate meaningful clinical data to validate that potential. Progress across our pipeline underscores the ability of our platform to generate first-in-class compounds across the previously undrugged family of cyclins, the master regulators of the cell cycle. We are grateful for the commitment and support of our existing and new investors."

"Cyclin D1 is a well-established driver of cancer, especially in ER-positive breast cancer where there is a lineage dependency on this cyclin, but directly targeting it has remained a longstanding challenge," said Marie Evangelista, Ph.D., chief scientific officer at Circle Pharma. "CID-165 is designed to selectively disrupt the interaction between cyclin D1 and retinoblastoma protein, providing a novel approach to directly targeting this fundamental driver of tumor growth. The robust activity we have observed across preclinical models in ER-positive breast cancer, both as a monotherapy and in combination with established treatments, gives us strong conviction in the potential of CID-165 as we prepare to advance the program into the clinic in the first quarter of 2027."

About Cyclin D1 and CID-165

Cyclin D1 is a regulatory protein that plays a crucial role in cell cycle progression and is dysregulated in some malignancies, including ER-positive breast cancer and certain lymphomas. In these cancers, dysregulated cyclin D1 drives abnormal cell proliferation through its inactivation of the tumor suppressor retinoblastoma protein (Rb) leading to uncontrolled cell division. In preclinical studies, CID-165 has been shown to potently and selectively disrupt the cyclin D1-Rb interaction allowing Rb to remain active and suppress cancer cell proliferation. CID-165 is a first-in-class, orally bioavailable, macrocyclic cyclin D1 RxL inhibitor that has demonstrated robust anti-tumor activity in cyclin D1-driven preclinical cancer models, including in combination with other therapies such as CDK4/6-dual inhibitors, CDK4-selective inhibitors and endocrine therapies.

(Press release, Circle Pharma, SEP 16, 2026, View Source [SID1234670895])

On September 16, 2026 Biomunex Pharmaceuticals, a biopharmaceutical company specialized in the discovery and development of innovative therapeutic approaches, reported that the U.S. Food and Drug Administration (FDA) has completed its Investigational New Drug (IND) review period for Ipsen’s IPN60330 (formerly BMX-502), the first MAIT cell engager (also referred to as a "MAIT engager") based on Biomunex’s proprietary BiXAb technology platforms, and for which Biomunex and Ipsen announced an exclusive global licensing agreement for development, manufacture and commercialization rights in 2024.

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This key step is the result of an intensive preclinical development effort, encompassing full drug bioproduction for the Phase 1 trial, regulatory studies and animal toxicology studies, conducted by the Biomunex team in partnership with Ipsen. It marks the upcoming initiation of Ipsen’s Phase I clinical trial in the USA, a significant step forward in the development of this novel therapeutic class in immuno-oncology.

IPN60330 is a bispecific antibody designed to selectively engage and activate MAIT cells (MucosalAssociated Invariant T cells), a subset of T cells present throughout the body, which are particularly enriched in mucosal and barrier tissues, and targets the GPC3 tumor antigen to kill cancer cells. GPC3 is a clinically validated target, highly expressed across several cancer types.

The completion of the FDA review period is a further demonstration of the quality of Biomunex’s proprietary BiXAb technologies. This first MAIT engager should overcome some of the limitations of classical pan-T cell engagers, which activate all T cells, including regulatory T cells, and can induce cytokine release syndrome, a potentially serious dose-limiting toxicity that represents a true problem for physicians and their cancer patients. MAIT engagers have the potential to provide a broader therapeutic window compared to classical pan-T cell engagers for treating specific tumor types.

Moreover, an improved therapeutic window with MAIT engagers should permit a stronger response from the adaptive immune system leading to improved and durable responses.

This new milestone has triggered a milestone payment linked to the completion of the FDA IND review period ahead of the upcoming entry into clinical development, under the exclusive global licensing agreement entered into between Ipsen and Biomunex in November 2024. In the context of this agreement, Biomunex is eligible to receive up to $610 million in total, including an upfront already received, contingent upon successful development, regulatory and commercial milestones, in addition to tiered global royalties on sales.

"The upcoming start of the clinical development program in the United States for IPN60330 is a recognition of the quality of our collaboration with Ipsen. Moreover, that’s a major milestone in our development, demonstrating the strength of our BiXAb technology platforms, as well as the expertise of our teams in generating breakthrough innovation", said Dr Simon Plyte, CSO of Biomunex. "It finally underscores our ability to develop innovative programs in partnership with a world-renowned pharmaceutical partner, with the potential to open new avenues in cancer immunotherapy," added Dr Pierre-Emmanuel Gerard, founder, President and CEO of Biomunex.

(Press release, BIOMUNEX Pharmaceuticals, SEP 16, 2026, View Source [SID1234670894])

On September 16, 2026 Avacta Therapeutics (AIM: AVCT), a life sciences company developing innovative, targeted oncology drugs, reported that it has achieved clinical proof of mechanism for AVA6103, its next-generation controlled-release pre|CISION peptide-drug conjugate (PDC) platform in the ongoing phase 1 FOCUS-01 trial.

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Preliminary data from the Phase 1a trial of AVA6103 in patients with select solid tumors demonstrate proof of mechanism with two key findings:

AVA6103 pre|CISION controlled-release exatecan demonstrates a clean safety profile through the first three dose levels, including a payload dose level 50% higher than the maximum tolerated dose (MTD) of conventional exatecan, and
The comparison of the preclinical modeled pharmacokinetic (PK) data and clinical trial PK data demonstrates an exceptional alignment through the first 3 dose levels with controlled release of exatecan evident in patients for days after dosing
The alignment of these critical datasets greatly increases our confidence that the safety profile, tumor selectivity and antitumor efficacy observed in the preclinical studies of AVA6103 will translate into the clinic.

The first head-to-head comparison of AVA6103 and Enhertu, a marketed antibody drug conjugate (ADC) that targets HER2, demonstrates that AVA6103 shows better antitumor activity vs. Enhertu, with deep and durable responses delivered by our dose dense regimen that has been applied in the FOCUS-01 trial.

Christina Coughlin, CEO of Avacta, commented:

"We are thrilled to report the proof of mechanism data with our first Next-Generation pre|CISION molecule in the clinic, which continues to underscore the potential of our platform to make a significant difference to cancer patients. AVA6103 moved from candidate status to Investigational New Drug application in less than a year, and has now reached an initial clinical readout with excellent safety and PK data, showing it is performing exactly as expected from the data generated in our preclinical studies.

"Our head-to-head comparison with the marketed ADC Enhertu shows better activity in a HER2+ preclinical model even at low FAP levels, with the dose-dense regimen demonstrating advantages of AVA6103 over traditional dosing of ADCs.

"We continue our discussions with potential partners on the Next Gen assets and these data greatly increase our partnering position across the Next Gen platform. The FOCUS-01 trial continues to enroll patients into two parallel arms and we look forward to providing further updates as the trial progresses.

"With FAP expression in ~90% of solid tumors, these clinical findings provide a gateway for Avacta to link multiple payloads and access previously unaddressable markets. This is a major inflection point for our Next Gen pre|CISION platform, providing the opportunity for pipeline expansion to benefit patients and shareholders alike"

Clinical Proof of Mechanism of AVA6103 in the FOCUS-01 Trial

Trial design and progress:

The FOCUS-01 Phase 1 clinical trial of AVA6103 is enrolling patients with locally advanced or metastatic disease with one of six indications, being: colorectal cancer, pancreatic ductal adenocarcinoma, gastric/gastroesophageal junction cancers, cervical cancer or small cell lung cancer.

The first three dose levels have completed enrollment of patients (n=19) in two parallel arms with doses administered every two weeks (Q2W) or every three weeks (Q3W) and assessed for safety and tolerability, PK / pharmacodynamics (PD) and preliminary efficacy. The first three dose levels in the AVA6103 trial were 1.5 mg/m2, 3 mg/m2 and 4.5 mg/m2 to enable the comparison to both the Phase 1 trial of Enhertu and conventional exatecan:
The first three dose levels are similar to the absolute payload dose levels in the published Enhertu Phase 1 trial (Doi, et al. 2017);
Dose level 2 of AVA6103 is similar to the MTD of conventional exatecan (Rowinsky, et al. 2000); and
Dose level 3 represents an approximate 50% increase over this MTD of conventional exatecan.
Safety, tolerability and PK data in the first three dose levels are presented. Screening is ongoing for enrollment of patients into both the Q2W and Q3W arms at dose level 4.

Safety data

Patients in the FOCUS-01 trial were treated with escalating doses (1.5 mg/m2 to 4.5 mg/m2) and assessed for safety and tolerability. These data were compared with published data for Enhertu (releasing a highly similar payload, deruxtecan) and with conventional exatecan administered in the standard regimen (once daily for five days).

The safety profile of AVA6103-derived exatecan is highly favorable at the first three dose levels when compared with equivalent dosing of topoisomerase I inhibitors (Topo Ii) (conventional exatecan and Enhertu-derived deruxtecan), with minimal toxicity reported with AVA6103.
Notably, AVA6103 produced little toxicity at the equivalent and escalated doses of the MTD of conventional exatecan in heavily pretreated patients (Rowinsky et al. 2000) and at similar payload doses in the first three cohorts in the Phase 1 of Enhertu (Doi et al. 2017). Relevant comparison data include:
Neutropenia: 0% with AVA6103, 22% with similar doses of Enhertu, and 64% at the MTD of conventional exatecan (equivalent to the 3 mg/m2 dose of AVA6103).
Thrombocytopenia: 5% (1/19) with AVA6103, 11% with Enhertu and 43% with conventional exatecan;
Anemia: 16% (3/19) with AVA6103, 11% with similar doses of Enhertu and 43% with conventional exatecan; and
Nausea and vomiting: 5% (1/19) with AVA6103, 44% with Enhertu and 67% with exatecan (reported across all dose levels in this trial).
Pharmacokinetic data

Patients were assessed for plasma PK properties across the first three dose levels of AVA6103 and compared to the corresponding dose levels of Enhertu.

As seen previously in preclinical models, the first three dose levels in the trial demonstrate rapid reduction in the plasma level of the PDC (AVA6103), with prolonged low-level release of both products of the cleavage reaction, the pre|CISION peptide and released exatecan.
Given the very short half-life of the released peptide (2-3 hours) that was demonstrated in the AVA6000 program, and the detection of low levels of the released peptide from AVA6103 in the plasma up to 48 hours after dosing indicates that the PDC is being retained in the tumor in a ‘drug reservoir’ that is slowly being cleaved to release the peptide and exatecan, as this mechanism was designed to do.
The remarkable consistency of these results with predictive PK modeling based on preclinical studies greatly increase our confidence that AVA6103 is performing as intended, and that the robust preclinical data will translate to the clinic and support ongoing dose-escalation and efficacy evaluation in the Phase 1 trial.
Preclinical efficacy comparison with Enhertu

The comparative efficacy of Enhertu and AVA6103 was tested in a head-to-head format using a gastric cancer patient-derived xenograft model that is HER2+ and FAP+ (by IHC).
When tumors had grown to 100-200 mm3 in size, animals were randomized to receive either AVA6103 or Enhertu at the preclinical dose with evidence of activity (Enhertu x 1 or AVA6103 QWx3 dose dense regimen).
Enhertu treatment resulted in a slowed growth compared to vehicle control, with two animals demonstrating small tumor reductions and 1/6 with progression as best response. In comparison, AVA6103 treatment resulted in deep and prolonged partial responses in 6/6 animals treated.
Outlook

The design of the FOCUS-1 trial of AVA6013 and preclinical updates will be presented in Trials in Progress presentations at both the American Association of Cancer Research (AACR) (Free AACR Whitepaper) Conference on Pancreatic Cancer, being held on September 25-28, 2026, and the European Society for Medical Oncology (ESMO) (Free ESMO Whitepaper) Congress, being held on October 23-27, 2026.
First efficacy data from the FOCUS-01 trial with AVA6103 is anticipated to be presented in H1 2027 – including data from clinical tumor biopsies which are anticipated to confirm AVA6103 is being retained in a ‘drug reservoir’ in the tumor, based on the preliminary Phase 1 data.
The selection of the payloads and data to support clinical candidate selection for the Dual Payload Next Gen Program (AVA6207) will be presented in Q4 2026.
Clinical data from the First Gen faridoxorubicin (AVA6000) program will also be presented in Q4 2026 at the ESMO (Free ESMO Whitepaper) Congress.
Enhertu (trastuzumab deruxtecan; T-DXd) is a protease cleavable-linker ADC, approved for both breast cancer and gastric cancer indications (an AstraZeneca/Daiichi Sankyo product). Enhertu is a registered trademark of Daiichi Sankyo Company, Limited and AstraZeneca.

(Press release, Avacta Life Sciences, SEP 16, 2026, View Source [SID1234670876])

On September 16, 2026 Daiichi Sankyo reported that Enhertu (trastuzumab deruxtecan) and Datroway (datopotamab deruxtecan) have been approved in Japan for two new indications in the first-line setting of patients with metastatic breast cancer.

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Enhertu in combination with pertuzumab was approved for the treatment of adult patients with HER2 positive unresectable or recurrent breast cancer. Datroway was approved for the treatment of adult patients with hormone receptor (HR) negative and HER2 negative unresectable or recurrent breast cancer, a subtype commonly referred to as triple negative breast cancer (TNBC).

Enhertu and Datroway are specifically engineered DXd antibody drug conjugates (ADC) discovered by Daiichi Sankyo (TSE: 4568) and being developed and commercialized by Daiichi Sankyo in Japan.

Breast cancer is the most common cancer among women in Japan. 1 Both HER2 positive and TNBC are aggressive breast cancer subtypes, with only about 30% and 15% of patients, respectively, living five years following diagnosis.2,3 For patients with these aggressive subtypes, treatments that significantly delay disease progression in the first-line metastatic setting are needed to improve long-term outcomes.

"These two approvals represent significant advances for the treatment of metastatic breast cancer. Enhertu in combination with pertuzumab is the first new treatment regimen in more than a decade for patients with metastatic HER2 positive disease and Datroway is the only TROP2 directed medicine to demonstrate an overall survival benefit for patients with metastatic triple negative breast cancer in the first-line setting," said Yuki Abe, PhD, Senior Executive Officer, Head of R&D Division in Japan and Head of Research, Daiichi Sankyo. "With these new approvals of Enhertu and Datroway, there are now two Daiichi Sankyo medicines available in Japan that can be used as first-line treatments across the most aggressive subtypes of metastatic breast cancer."

Data Supporting Enhertu Approval

The approval of Enhertu by Japan’s Ministry of Health, Labour and Welfare (MHLW) is based on results from the DESTINY-Breast09 phase 3 trial. In the trial, Enhertu in combination with pertuzumab reduced the risk of disease progression or death by 44% versus taxane, trastuzumab and pertuzumab (THP) (hazard ratio [HR]=0.56; 95% confidence interval [CI]: 0.44-0.71; p<0.00001) in patients (n=383) with HER2 positive metastatic breast cancer who had not received prior chemotherapy or HER2 targeted therapy or had received neoadjuvant or adjuvant HER2 targeted therapy more than six months before the diagnosis of advanced or metastatic disease. Median progression-free survival (PFS) was 40.7 months (95% CI: 36.5-not estimable [NE]) with Enhertu in combination with pertuzumab compared to 26.9 months (95% CI: 21.8-NE) with THP as assessed by blinded independent central review (BICR). These data were presented at the 2025 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting and subsequently published in The New England Journal of Medicine.

In DESTINY-Breast09, the safety profile of Enhertu was consistent with previous clinical trials with no new safety concerns identified. Adverse reactions occurred in 373 patients (97.9%) treated with Enhertu (5.4 mg/kg) in combination with pertuzumab including 39 Japanese patients. The most common adverse reactions were nausea (71.1%), diarrhea (55.9%), alopecia (46.2%), vomiting (42.0%) and anemia (34.9%). Interstitial lung disease (ILD) occurred in 33.3% of Japanese patients treated with Enhertu in combination with pertuzumab as determined by an independent ILD adjudication committee.

Data Supporting Datroway Approval

The approval of Datroway by Japan’s MHLW is based on results from the TROPION-Breast02 phase 3 trial, which included patients with metastatic TNBC who experienced early relapse following prior treatment and were not candidates for PD-1/PD-L1 inhibitor therapy. In this trial, Datroway demonstrated a statistically significant and clinically meaningful 5.0 month improvement in median overall survival (OS) versus investigator’s choice of chemotherapy (HR=0.79; 95% CI: 0.64-0.98; p=0.029). Median OS was 23.7 months for patients treated with Datroway versus 18.7 months for those treated with chemotherapy. Datroway reduced the risk of disease progression or death by 43% compared to chemotherapy (HR=0.57; 95% CI: 0.47-0.69; p<0.0001) as assessed by BICR. Median PFS was 10.8 months for patients treated with Datroway versus 5.6 months for those treated with chemotherapy. These data were presented at the 2025 European Society for Medical Oncology Congress and subsequently published in Annals of Oncology.

In TROPION-Breast02, the safety profile of Datroway was consistent with previous clinical trials with no new safety concerns identified. Adverse reactions occurred in 296 patients (92.8%) treated with Datroway (6 mg/kg) including 17 Japanese patients. The most common adverse reactions included stomatitis (57.1%), nausea (44.5%), alopecia (40.8%), dry eye (23.8%) and constipation (22.6%). ILD was not observed in the 17 Japanese patients treated with Datroway.

Both Enhertu and Datroway are approved in Japan with a Warning in their prescribing information for ILD. ILD occurred in 11.7% of patients treated with Enhertu and 3.1% of patients treated with Datroway across multiple clinical trials. As cases of ILD, including fatal cases, have occurred in Enhertu and Datroway treated patients, both medicines are to be used in close collaboration with a respiratory disease expert. Patients should be closely observed during therapy by monitoring for early signs or symptoms of ILD (such as dyspnea, cough or fever) and performing periodical percutaneous oxygen saturation (SpO2) tests, chest X-ray scans and chest CT scans. If abnormalities are observed, discontinue administration of Enhertu or Datroway and take appropriate measures, such as corticosteroid administration. Prior to initiation of Enhertu or Datroway therapy, a chest CT scan should be performed and medical history taken to confirm the absence of any comorbidity or history of ILD with the patient and carefully consider the eligibility of the patient for Enhertu or Datroway therapy.

About DESTINY-Breast09

DESTINY-Breast09 is a global, multicenter, randomized, open-label, phase 3 trial evaluating the efficacy and safety of Enhertu (5.4 mg/kg) either alone or in combination with pertuzumab versus standard of care THP as firstline treatment in patients with HER2 positive metastatic breast cancer.

Patients were randomized 1:1:1 to receive either Enhertu monotherapy with a pertuzumab matching placebo; Enhertu in combination with pertuzumab; or THP. Randomization was stratified by prior treatment (de novo metastatic disease versus progression from early-stage disease), HR status and PIK3CA mutation status.

The primary endpoint of DESTINY-Breast09 is PFS as assessed by BICR in the Enhertu monotherapy and Enhertu combination arms. Secondary endpoints include investigator-assessed PFS, OS, overall response rate (ORR), duration of response (DoR), pharmacokinetics and safety. The investigational arm assessing Enhertu monotherapy versus THP remains blinded to patients and investigators and will continue to the final PFS analysis. DESTINY-Breast09 enrolled 1,157 patients across multiple sites in Africa, Asia, Europe, North America and South America. For more information about the trial, visit ClinicalTrials.gov

About TROPION-Breast02

TROPION-Breast02 is a global, multicenter, randomized, open-label phase 3 trial evaluating the efficacy and safety of Datroway versus investigator’s choice of chemotherapy (paclitaxel, nab-paclitaxel, capecitabine, carboplatin or eribulin) in patients with previously untreated locally recurrent inoperable or metastatic TNBC for whom immunotherapy was not an option. This included patients whose tumors did not express PD-L1 as well as patients with PD-L1 expressing tumors who could not receive immunotherapy due to prior exposure in early-stage disease, comorbidities or immunotherapy not being accessible in their geography. Enrollment included patients with de novo or recurrent disease, regardless of disease-free interval, and those with poor prognostic factors such as stable brain metastases.

The dual primary endpoints of TROPION-Breast02 are OS and PFS as assessed by BICR. Secondary endpoints include PFS as assessed by investigator, ORR, DoR, disease control rate, pharmacokinetics and safety.

TROPION-Breast02 enrolled 644 patients at sites in Africa, Asia, Europe, North America and South America. For more information visit ClinicalTrials.gov.

About Metastatic Breast Cancer

Breast cancer is the most common cancer in women and the leading cause of cancer-related deaths among women worldwide. 4 Approximately 2.4 million breast cancer cases were diagnosed in 2024, with more than 690,000 deaths globally.4 In Japan, breast cancer is the most common cancer in women, with approximately 94,000 cases diagnosed and 16,800 deaths in 2024.

There are three main breast cancer subtypes: HR positive, HER2 positive and TNBC.2,5,6 Approximately 15% to 20% of breast cancer cases are considered HER2 positive where the disease is driven by overexpression or amplification of HER2, and 15% are considered to be triple negative where the tumor tests negative for estrogen receptors, progesterone receptors or overexpression of HER2. 7,8 Both HER2 positive and TNBC are aggressive breast cancer subtypes, with only about 30% and 15% of patients, respectively, living five years following diagnosis.

While HER2 targeted therapies have improved outcomes for patients with HER2 positive metastatic breast cancer, prognosis remains poor with most patients experiencing disease progression within two years of first-line treatment with THP, which has been the standard of care for more than a decade.

For patients with metastatic TNBC with PD-L1 expressing tumors, the addition of immunotherapy to chemotherapy has improved outcomes in the first-line setting.13,14 However, for approximately 70% of patients with metastatic TNBC who are not candidates for immunotherapy, chemotherapy was the standard first-line treatment.

(Press release, Daiichi Sankyo, SEP 16, 2026, View Source [SID1234670875])