PURPOSE: Trastuzumab deruxtecan (T-DXd) is a human epidermal growth factor 2 (HER2)–directed antibody-drug conjugate approved in HER2-expressing breast and gastric cancers and HER2-mutant non–small-cell lung cancer. Treatments are limited for other HER2-expressing solid tumors. METHODS: This open-label phase II study evaluated T-DXd (5.4 mg/kg once every 3 weeks) for HER2-expressing (immunohistochemistry [IHC] 3+/2+ by local or central testing) locally advanced or metastatic disease after ≥1 systemic treatment or without alternative treatments. The primary end point was investigator-assessed confirmed objective response rate (ORR). Secondary end points included safety, duration of response, progression-free survival (PFS), and overall survival (OS). RESULTS: At primary analysis, 267 patients received treatment across seven tumor cohorts: endometrial, cervical, ovarian, bladder, biliary tract, pancreatic, and other. The median follow-up was 12.75 months. In all patients, the ORR was 37.1% (n = 99; [95% CI, 31.3 to 43.2]), with responses in all cohorts; the median DOR was 11.3 months (95% CI, 9.6 to 17.8); the median PFS was 6.9 months (95% CI, 5.6 to 8.0); and the median OS was 13.4 months (95% CI, 11.9 to 15.5). In patients with central HER2 IHC 3+ expression (n = 75), the ORR was 61.3% (95% CI, 49.4 to 72.4), the median DOR was 22.1 months (95% CI, 9.6 to not reached), the median PFS was 11.9 months (95% CI, 8.2 to 13.0), and the median OS was 21.1 months (95% CI, 15.3 to 29.6). Grade ≥3 drug-related adverse events were observed in 40.8% of patients; 10.5% experienced adjudicated drug-related interstitial lung disease (ILD), with three deaths. CONCLUSION: Our study demonstrates durable clinical benefit, meaningful survival outcomes, and safety consistent with the known profile (including ILD) in pretreated patients with HER2-expressing tumors receiving T-DXd. Greatest benefit was observed for the IHC 3+ population. These data support the potential role of T-DXd as a tumor-agnostic therapy for patients with HER2-expressing solid tumors.

There is a need to develop and validate biomarkers for treatment response and survival in tubo-ovarian high-grade serous carcinoma (HGSC). The chemotherapy response score (CRS) stratifies patients into complete/near-complete (CRS3), partial (CRS2), and no/minimal (CRS1) response after neoadjuvant chemotherapy (NACT). Our aim was to review current evidence to determine whether the CRS is prognostic in women with tubo-ovarian HGSC treated with NACT. We established an international collaboration to conduct a systematic review and meta-analysis, pooling individual patient data from 16 sites in 11 countries. Patients had stage IIIC/IV HGSC, 3-4 NACT cycles and >6-months follow-up. Random effects models were used to derive combined odds ratios in the pooled population to investigate associations between CRS and progression free and overall survival (PFS and OS). 877 patients were included from published and unpublished studies. Median PFS and OS were 15 months (IQR 5-65) and 28 months (IQR 7-92) respectively. CRS3 was seen in 249 patients (28%). The pooled hazard ratios (HR) for PFS and OS for CRS3 versus CRS1/CRS2 were 0·55 (95% CI, 0·45-0·66; P < 0·001) and 0·65 (95% CI 0·50-0·85, P = 0·002) respectively; no heterogeneity was identified (PFS: Q = 6·42, P = 0·698, I2 = 0·0%; OS: Q = 6·89, P = 0·648, I2 = 0·0%). CRS was significantly associated with PFS and OS in multivariate models adjusting for age and stage. Of 306 patients with known germline BRCA1/2 status, those with BRCA1/2 mutations (n = 80) were more likely to achieve CRS3 (P = 0·027). CRS3 was significantly associated with improved PFS and OS compared to CRS1/2. This validation of CRS in a real-world setting demonstrates it to be a robust and reproducible biomarker with potential to be incorporated into therapeutic decision-making and clinical trial design.

Background and Aims: Targeting costimulatory receptors with agonistic antibodies is a promising cancer immunotherapy option. We aimed to investigate costimulatory receptor expression, particularly 4‐1BB (CD137 or tumor necrosis factor receptor superfamily member 9), on tumor‐infiltrating CD8⁺ T cells (CD8⁺ tumor‐infiltrating lymphocytes [TILs]) and its association with distinct T‐cell activation features among exhausted CD8⁺ TILs in hepatocellular carcinoma (HCC). Approach and Results: Tumor tissues, adjacent nontumor tissues, and peripheral blood were collected from HCC patients undergoing surgical resection (n = 79). Lymphocytes were isolated and used for multicolor flow cytometry, RNA‐sequencing, and in vitro functional restoration assays. Among the examined costimulatory receptors, 4‐1BB was most prominently expressed on CD8⁺ TILs. 4‐1BB expression was almost exclusively detected on CD8⁺ T cells in the tumor—especially on programmed death 1 (PD‐1)^high cells and not PD‐1^int and PD‐1^neg cells. Compared to PD‐1^int and 4‐1BB^negPD‐1^high CD8⁺ TILs, 4‐1BB^posPD‐1^high CD8⁺ TILs exhibited higher levels of tumor reactivity and T‐cell activation markers and significant enrichment for T‐cell activation gene signatures. Per‐patient analysis revealed positive correlations between percentages of 4‐1BB^pos cells among CD8⁺ TILs and levels of parameters of tumor reactivity and T‐cell activation. Among highly exhausted PD‐1^high CD8⁺ TILs, 4‐1BB^pos cells harbored higher proportions of cells with proliferative and reinvigoration potential. Our 4‐1BB–related gene signature predicted survival outcomes of HCC patients in the The Cancer Genome Atlas cohort. 4‐1BB agonistic antibodies enhanced the function of CD8⁺ TILs and further enhanced the anti‐PD‐1–mediated reinvigoration of CD8⁺ TILs, especially in cases showing high levels of T‐cell activation. Conclusion: 4‐1BB expression on CD8⁺ TILs represents a distinct activation state among highly exhausted CD8⁺ T cells in HCC. 4‐1BB costimulation with agonistic antibodies may be a promising strategy for treating HCCs exhibiting prominent T‐cell activation.

The survival of patients with ovarian cancer has improved because of surgery and chemotherapy. This study aimed to estimate the changes in survival rates among Korean women with ovarian cancer prior to the introduction of targeted therapy for ovarian cancer. Data were obtained from the Korea Central Cancer Registry regarding patients who were diagnosed with epithelial ovarian cancer between 1995 and 2014. The relative survival rates were calculated for 5-year periods using the Ederer II method. Cox proportional hazard models were created to assess the associations of demographic and clinicopathological factors with ovarian cancer survival. During the study period, 22,880 women were diagnosed with epithelial ovarian cancer. The 5-year relative survival rate improved from 57.2% during 1995–1999 to 63.8% during 2010–2014 (P < 0.001). Survival outcomes improved between 1995 and 1999 and 2010–2014 for the serous and endometrioid carcinoma subtypes (P < 0.001). However, no improvements were observed for the mucinous and clear cell carcinoma subtypes (P = 0.189 and P = 0.293, respectively). Multivariate analysis revealed that younger age, early stage, recent diagnosis, primary surgical treatment, and non-serous histological subtype were favorable prognostic factors. Survival outcomes have improved for serous and endometrioid epithelial ovarian cancer in the last 20 years. However, no improvement was observed for patients with mucinous and clear cell carcinoma subtypes.