On December 9, 2025 Tempus AI, Inc. (NASDAQ: TEM), a technology company leading the adoption of AI to advance precision medicine, reported that ten abstracts have been accepted for presentation at the 2025 San Antonio Breast Cancer Symposium (SABCS). The meeting takes place December 9–12 at the Henry B. González Convention Center in San Antonio, Texas.

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"This year at SABCS, our research highlights the power of multimodal data to help unravel the complexity of breast cancer," said Ezra Cohen, MD, Chief Medical Officer of Oncology at Tempus. "By integrating genomic, transcriptomic, and real-world clinical data, we are moving beyond broad disease classifications to uncover specific molecular drivers of progression and resistance. These insights are essential for pinpointing patient populations who may benefit from novel therapies and for optimizing treatment strategies to ultimately improve outcomes for those with advanced disease."

Tempus will highlight its latest scientific and clinical research findings via ten poster presentations:

Integrative Modeling of Multimodal Real-World Data for Improved Risk Stratification of First-Line CDK4/6 Inhibitor Outcomes in Patients with Estrogen Receptor (ER)-Positive/Human Epidermal Growth Factor Receptor 2 (HER2)-Negative Metastatic Breast Cancer
Date/Time: Wednesday, December 10, 2025, 12:30 p.m. – 2:30 p.m. CDT

Presentation Number: PS1-11-08

Summary: We developed a machine learning model that used clinical, genomic, and transcriptomic features to stratify patients with ER-positive/HER2-negative metastatic breast cancer, based on response to first-line CDK4/6 inhibitor plus endocrine treatment and identify predictors of response. This study demonstrated that multimodal real-world data collected during routine care can provide valuable insights into the biology of response to CDK4/6 inhibitors in patients with metastatic breast cancer and help improve patient stratification.
Distinct Transcriptional and Immunosuppressive Microenvironment Signatures in PIK3CA- and ESR1-Mutant Hormone Receptor Positive (HR+)/HER2- Metastatic Breast Cancer (MBC)
Date/Time: Wednesday, December 10, 2025, 12:30 p.m. – 2:30 p.m. CDT

Presentation Number: PS1-11-22

Summary: This study compared transcriptomic and immune profiles in HR+/HER2- metastatic breast cancer across wild-type, PIK3CA-mutant, ESR1-mutant, and co-mutant groups. SFRP2 downregulation was specific to ESR1-mutant tumors, while SCGB2A2 was robustly upregulated in PIK3CA-mutant and co-mutant tumors, suggesting its potential as a diagnostic and therapeutic target. Immune analysis revealed increased M2 macrophages and regulatory T cells in PIK3CA-mutant and co-mutant tumors, with the most pronounced immunosuppressive microenvironment in PIK3CA-mutant cases.

Clinical and Molecular Landscape of ESR1 and PIK3CA Co-Mutated Hormone Receptor–Positive Metastatic Breast Cancer (HR+ MBC): Insights from 8,626 Patients Including Polyclonality and TP53 Alterations
Date/Time: Wednesday, December 10, 2025, 12:30 p.m. – 2:30 p.m. CDT

Presentation Number: PS1-11-16

Summary: Distinct mutation groups—no-MUT, PIK3CA-MUT, ESR1-MUT, and co-MUT (PIK3CA + ESR1)—exhibited unique clinical and genomic features; co-MUT was linked to more bone metastases, elevated tumor mutational burden, increased polyclonality, and shorter real-world overall survival. Notably, the frequency of ESR1 and co-mutations was higher in patients who underwent late molecular testing, indicating these alterations often emerge after extended endocrine therapy and highlighting the importance of timing in molecular assessment for guiding treatment strategies.
Clinicogenomic and Immune Profiles of Male Breast Cancer by Race: Insights from a Large Real-World Cohort
Date/Time: Wednesday, December 10, 2025, 5:00 p.m. – 6:30 p.m. CDT

Presentation Number: PS2-06-28

Summary: Real-world analysis of male breast cancer revealed broadly similar clinicogenomic profiles between Black and White patients, with HR+/HER2-negative and luminal subtypes predominating. Notable immune microenvironment differences—lower M2 macrophage infiltration and higher PD-L1 negativity in Black patients—may impact immunotherapy response and warrant further research into racial variation.
Cathepsin Protease Expression and Therapeutic Outcomes to Trastuzumab Deruxtecan (T-DXd) in Metastatic Breast Cancer
Date/Time: Wednesday, December 10, 2025, 5:00 p.m. – 6:30 p.m. CDT

Presentation Number: PS2-08-18

Summary: This study characterized pre-treatment expression of cathepsin proteases prior to T-DXd (cleavable linker) vs. T-DM1 (non-cleavable linker) treatment to understand their impact on clinical outcomes in metastatic breast cancer using the Tempus real-world database. This study demonstrated that among T-DXd treated patients, high cathepsin B and L protease expression was associated with improved outcomes in patients with HR+/HER2- disease, whereas in HER2+ patients, high expression of these proteases was associated with worse survival. In contrast, in the T-DM1 cohort there were no significant associations between protease expression and OS in the overall cohort as well as in the HER2+ cohort. This highlights the potential role of proteases as biomarkers of response to T-DXd in HER2 low/ultralow, but not HER2+ metastatic breast cancer.
Treatment Sequencing in HR+ HER2- Metastatic Breast Cancer and Associated Real World Outcomes
Date/Time: Wednesday, December 10, 2025, 5:00 p.m. – 6:30 p.m. CDT

Presentation Number: PS2-04-11

Summary: This study investigates the impact of first-line and second-line therapy selections on real-world progression-free survival (rwPFS) and real-world overall survival (rwOS) in patients with HR+ HER2- mBC. CDK4/6i significantly outperforms taxane in first-line. Patients who received second-line CDK4/6i following first-line taxane had longer second-line rwPFS than those who received CDK4/6i first-line treatment. The findings suggest that taxane may cause sensitization to CDK4/6i, potentially conferring better survival outcomes in a subset of patients where first-line taxane is advised, or a potential advantage to chemo before CDK4/6i re-challenge.
Real-World Second-Line Treatment Use and Clinical Outcomes in Patients With HR-Positive/HER2-Negative Metastatic Breast Cancer and an ESR1 Mutation
Date/Time: Wednesday, December 10, 2025, 5:00 p.m. – 6:30 p.m. CDT

Presentation Number: PS2-06-18

Summary: The study objective was to characterize real-world second-line treatment use and clinical outcomes (rwPFS and rwOS) in a metastatic breast cancer patient population with positive ESR1m test after first-line treatment with AI+CDK4/6i. Findings show that this cohort describes a complex subgroup of patients to treat, with rwPFS outcomes highlighting the need for more effective strategies that address resistance to AI+CDK4/6i and improve patient outcomes. Results from Flatiron Health EHR and Tempus both indicated consistent findings.
Comparative Analysis of the Tumor Immune Microenvironment (TIME) and Primary and Metastatic Tissue in HR+/HER2- and Triple-Negative Breast Cancer (TNBC)
Date/Time: Thursday, December 11, 2025, 12:30 p.m. – 2:00 p.m. CDT

Presentation Number: PS3-12-27

Summary: Tempus Lens was leveraged to assess the Tumor Immune Microenvironment (TIME) across metastatic sites of disease in HR+/HER2- breast cancer compared to TNBC, finding significant differences by site in both subtypes, with HR+/HER2- cancer being less immunogenic overall. Lung, pleura, and peritoneum metastases, along with breast and lymph nodes, showed the highest CD8+ T cell proportions, suggesting a subset of HR+/HER2- patients with these sites may potentially respond to Immune Checkpoint Inhibitor (ICI) therapy. This high variability of TIME profiles across metastatic sites warrants further study in prospective trials to guide patient selection for ICI.
The Molecular and Immune Landscape of HER2 Positive Breast Cancer
Date/Time: Thursday, December 11, 2025, 5:00 p.m. – 6:30 p.m. CDT

Presentation Number: PS4-05-21

Summary: Tempus Lens was employed to evaluate the tumor immune microenvironment of HER2+ breast cancer, assessing immune cell infiltration, TMB, PD-L1 status, and HLA allele prevalence, to uncover biomarkers for treatment guidance. A notable percentage of patients with localized and de novo metastatic disease displayed TMB high status and/or PD-L1 positivity. Additionally, TMB-high and PD-L1 positive patients with de novo metastatic disease treated with first-line chemotherapy or anti-HER2 therapy had significantly worse real-world overall survival (rwOS), suggesting a potential therapeutic benefit of incorporating immunotherapy into the treatment paradigm, in both localized and metastatic disease settings. Furthermore, observed ethnic HLA polymorphisms in the cohort may contribute to differences in outcomes and could potentially guide the development of population-specific immunotherapeutic strategies.

Real-World Data (RWD) Outcome Analysis of ESR1 Mutation Emergence in HR+/HER2- Metastatic Breast Cancer Through the Continuum of Standard of Care Hormonal Therapy
Date/Time: Friday, December 12, 2025, 12:30 p.m. – 2:00 p.m. CDT
Presentation Number: PS5-05-02
Summary: This large multimodal RWD outcome analysis from longitudinal molecular surveillance testing (xF) in HR+/HER2- mBC pts treated with AI+CDK4/6i sheds light on the continuum of ESR1m emergence and patient outcomes from first-line and beyond outside of clinical trial data. Analyses show higher ESR1m incidence is associated with reduced survival regardless of line of therapy.

(Press release, Tempus, DEC 9, 2025, View Source [SID1234661335])

On December 9, 2025 Xencor, Inc. (NASDAQ:XNCR), a clinical-stage biopharmaceutical company developing engineered antibodies for the treatment of cancer and autoimmune diseases, reported the issuance of U.S. Patent 12,492,253, which covers Xencor’s Xtend Fc domain for extending the half-life of antibodies targeting C5, with a term that extends into December 2028. The new patent term is approximately three years longer than the previous latest-to-expire U.S. patent covering the Xtend Fc domain.

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Xencor now anticipates receiving low-single digit royalties on net sales of Ultomiris (ravulizumab-cwvz), an anti-C5 antibody engineered with a licensed Xtend Fc domain, into December 2028 in the United States. Ultomiris is a drug being developed and commercialized by Alexion Pharmaceuticals, Inc., and is a registered trademark of Alexion. Xencor has also previously secured regulatory extensions of exclusivity in several EU countries, Japan and Australia.

"Xencor’s Xtend antibody half-life extension technology is one of several modular XmAb Fc domains that power Xencor’s XmAb medicines and drug candidates across internal and partner portfolios," said Bassil Dahiyat, Ph.D., president and chief executive officer at Xencor. "Importantly, this patent term extension also extends the U.S. royalty term for Ultomiris by approximately three years. We anticipate the resulting additional revenue will support our internal pipeline as it advances into later stages of clinical development and will drive further innovation across our portfolio, continuing to fuel the cycle of value creation that has been central to our strategy."

In 2023, OMERS, one of Canada’s largest defined benefit pension plans, acquired royalties due to Xencor on global Ultomiris sales subject to annual caps beginning in 2026. For potential sales related to Ultomiris occurring between 2026 and 2028, OMERS is entitled to receive up to $35 million annually with excess reverting to Xencor. For the nine-month period ending September 30, 2025, Xencor recognized non-cash royalty revenue of $51.0 million. Based upon consensus sales forecasts of Ultomiris, Xencor estimates recognizing potential royalty revenue in excess of the caps in the range of $100 million to $120 million in aggregate for the extended patent term through 2028.

(Press release, Xencor, DEC 9, 2025, View Source [SID1234661320])

On December 9, 2025 Natera, Inc. (NASDAQ: NTRA), a global leader in cell-free DNA and precision medicine, reported the results from two oral presentations that were presented at the American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting.

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Real-world Signatera Analysis: Oral Presentation on December 6

A real-world analysis of personalized circulating tumor DNA (ctDNA) detection in lymphoma evaluated 144 patients across 14 lymphoma subtypes, including aggressive and indolent lymphomas and patients undergoing chimeric antigen receptor T-cell (CAR-T) therapy. Signatera was used clinically to assess baseline ctDNA detection, track molecular clearance during first-line (1L) therapy, and evaluate end-of-treatment (EOT) ctDNA status and post-CAR-T response. Key findings included:

Across 14 subtypes of lymphoma, 94% of patients had detectable ctDNA in a pre-treatment sample.
ctDNA clearance during treatment was highly predictive of CAR-T response (p = 0.0028).
Rapid ctDNA clearance after one cycle of chemotherapy was more predictive of positive outcomes vs. delayed clearance after two cycles of therapy (HR: 20.95 vs. 7.45).
Signatera status at the end of 1L therapy was highly prognostic of event-free survival (HR: 49.77, p<0.0001), outperforming standard of care PET-CT response assessment across lymphoma subtypes.
HOVON Study: Oral Presentation on December 7

The HOVON study was conducted by Foresight Diagnostics, a subsidiary of Natera, in collaboration with Amsterdam University Medical Centers, the Hemato-Oncology Foundation for Adults in the Netherlands (HOVON) and the Netherlands Comprehensive Cancer Organization (IKNL). The study evaluated longitudinal molecular residual disease (MRD) surveillance in 166 patients with diffuse large B-cell lymphoma. The study provided one of the most detailed evaluations to date of ctDNA-MRD dynamics over a two-year surveillance period using the CLARITY ctDNA assay. Key findings included:

The CLARITY ctDNA assay showed early molecular response was associated with improved clinical outcomes, demonstrating its utility as an early risk-stratification marker.
Following any negative ctDNA test during surveillance, the probability of remaining relapse-free was 99% at 6 months and 97% at 12 months.
Early on-treatment molecular response could serve as a dynamic marker for therapy de-escalation or escalation trials, enabling adaptive trial designs.
"These presentations highlight the value of ctDNA in assessing treatment response and long-term risk across lymphoma subtypes, including diffuse large B-cell lymphoma," said Minetta Liu, M.D., chief medical officer of oncology and early cancer detection at Natera. "The findings reinforce how the detection of disease at the molecular level can support more personalized treatment and surveillance strategies for patients with cancer."

(Press release, Natera, DEC 9, 2025, View Source [SID1234661336])

On December 9, 2025 Alligator Bioscience (Nasdaq Stockholm: ATORX) reported on the announcement by Shanghai Henlius Biotech, Inc. that applications for Phase 2/3 clinical trials of HLX22 (recombinant humanised anti-HER2 monoclonal antibody injection) in combination with HLX87 (an antibody-drug conjugate targeting HER2) have been approved by China’s National Medical Products Administration (NMPA). The trials are intended for first-line treatment of HER2-positive breast cancer and for neoadjuvant treatment of HER2-positive breast cancer.

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HLX22 is an anti-HER2 monoclonal antibody being developed by Henlius under a license from AbClon, Inc., following a discovery collaboration which grants Alligator the right to participate in potential future revenues.

"Shanghai Henlius regulatory approvals to initiate Phase 2/3 trials of HLX22 in HER2-positive breast cancer represent continued progress for this programme and broaden its clinical development," said Søren Bregenholt, CEO of Alligator Bioscience. "While Alligator is not directly involved in the development, we follow HLX22 closely as it represents an opportunity for future revenue streams from milestones and royalties upon potential approval."
Under the terms of the license agreement, Alligator is entitled to 35% of AbClon’s revenue from its sublicense agreement with Henlius. For further information and the latest updates on HLX22’s clinical development, please refer to Henlius’ announcement available on HKEXnews.

(Press release, Alligator Bioscience, DEC 9, 2025, View Source [SID1234661305])

On December 9, 2025 Aptevo Therapeutics Inc. (NASDAQ:APVO), a clinical-stage biotechnology company focused on developing novel immune-oncology therapeutics based on its proprietary ADAPTIR and ADAPTIR-FLEX platform technologies, reported preliminary results from its ongoing Phase 1b/2 RAINIER study evaluating mipletamig, a CD123 x CD3 bispecific molecule, in combination with azacitidine and venetoclax (AZA/VEN) for newly diagnosed acute myeloid leukemia (AML) patients who are unfit for intensive chemotherapy. The data were presented on December 8, 2025, in a poster session at the American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting.

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Across dose-optimization Cohorts 1-3, mipletamig combined with AZA/VEN demonstrated high remission rates and a compelling safety/tolerability profile, reinforcing the potential of T-cell engagement in frontline AML when safety can be effectively managed. Aptevo’s proprietary use of the CRIS-7-derived CD3 binding domain differentiates mipletamig in the category.

Key Findings

100% of treated patients remained free of cytokine release syndrome (CRS) across cohorts to date

93% overall response rate (ORR) among evaluable patients

87% achieved CR/CRi*

73% achieved CR

60% of MRD evaluable CR/CRi patients achieved minimum residual disease negative status, a result that is typically associated with stronger, more durable responses

43% of ORR patients had a TP53 genetic mutation, a marker that is typically associated with poor prognosis in AML patients

*Remission = complete remission (CR) and, complete remission with blood markers that have not yet recovered (CRi).

Median patient age was 75, reflecting a population that is underserved by intensive therapies. In the RAINIER trial to date, the triplet regimen was generally well tolerated. Infusion-related reactions and hematologic events were the most common adverse events, consistent with expectations for this patient population. Importantly, no CRS was seen, supporting the molecule’s differentiated safety profile in combination therapy.

"These data, particularly the remission rates and absence of CRS, underscore the promise of mipletamig as part of a frontline AML regimen," said Dirk Huebner, MD, Chief Medical Officer. "We are encouraged by the safety and efficacy profile we are seeing across cohorts, and we look forward to advancing the program into later-stage evaluation."

The RAINIER study continues to enroll patients across additional dose levels. Mipletamig’s design leverages Aptevo’s ADAPTIR platform to deliver targeted T-cell engagement with the goal of minimizing systemic immune activation-an important factor in realizing the full therapeutic potential of T-cell engagers in AML.

About the RAINIER Trial
RAINIER, a frontline AML study, is a Phase 1b/2 dose optimization, multi-center, multi-cohort, open label study. Subjects are adults aged 18 or older, newly diagnosed with AML who are not eligible for intensive induction chemotherapy. RAINIER will be conducted in two parts. First, a Phase 1b dose optimization study in frontline AML patients followed by a Phase 2 study. The Phase 1b trial consists of 28-day cycles of treatment across multiple, sequential cohorts.

About Mipletamig
Aptevo’s wholly owned lead proprietary drug candidate, mipletamig, being evaluated for the treatment of AML, is differentiated by design to redirect the immune system of the patient to destroy leukemic cells and leukemic stem cells expressing the target antigen CD123, which is a compelling target for AML due to its overexpression on leukemic stem cells and AML blasts. This antibody-like recombinant protein therapeutic is designed to engage both leukemic cells and T cells of the immune system and bring them closely together to trigger the destruction of leukemic cells. Mipletamig is purposefully designed to reduce the likelihood and severity of CRS by use of the CRIS-7-derived CD3 binding pathway an approach that differentiates Aptevo from competitors. Mipletamig has received orphan drug designation ("orphan status") for AML according to the Orphan Drug Act. Orphan drug designation provides key advantages-including the opportunity to seek U.S. market exclusivity for a specific period of time upon approval, FDA fee reductions, and access to development and tax credits. Mipletamig has been evaluated in more than 100 patients over three trials to date.

(Press release, Aptevo Therapeutics, DEC 9, 2025, View Source [SID1234661321])