In HR+ cohort, for ENHERTU (N=331), median overall survival (months)=23.90 (95% Cl 20.80-24.80), Confirmed Objective Response Rate=52.90% (95% Cl 47.30-58.40), Complete Response rate=36.00%, Partial Response rate= 49.50%, median Duration of Response (months)=10.70 (95% Cl 8.50-13.70); for Chemotherapy (N=163), median overall survival (months)=17.50 (95% Cl 15.20-24.80), Confirmed Objective Response Rate=16.60% (95% Cl 11.20-23.20), Complete Response rate=0.60%, Partial Response rate= 16.00%, median Duration of Response (months)=6.80 (95% Cl 6.50-9.90). In HR+ and HR- cohort, for ENHERTU (N=373), median Progression-Free Survival (mFPS)=9.90 months (95% Cl 9.00-11.30), median overall survival (months) = 23.40 (95% Cl 20.00-24.80), Confirmed Objective Response Rate = 52.30% (95% Cl 47.10-57.40), Complete Response rate=35.00%, Partial Response rate= 49.10%, median Duration of Response(months)=10.70 (95% Cl 8.50-13.20); for Chemotherapy (N=184), median Progression-Free Survival (mFPS)=5.40 months(95% Cl 4.20-6.80), median overall survival (months)=16.80(95% Cl 14.50-20.00), Confirmed Objective Response Rate=16.30% (95% Cl 11.30-22.50), Complete Response rate=11.00%, Partial Response rate= 15.20%, median Duration of Response(months)=6.80 (95% Cl 6.00-9.90).

The median patient age was 54 years. Approximately 50% of patients were treated with 0-1 prior lines of therapy in the metastatic setting, and 50% were treated with 2 prior treatment regimens. At baseline, 16.50% of patients in the T-DXd group and 14.80% of those in the T-DM1 group had brain metastases. At a median follow-up of 15.90 months, T-DXd significantly improved PFS by 72% compared with T-DM1 across all patient subgroups. Findings were consistent irrespective of hormone receptor status, prior treatment with pertuzumab, number of prior lines of therapy, presence or absence of visceral disease, and presence or absence of brain metastases. The overall response rate (ORR) in the overall study cohort was 79.70% and 34.20% in the T-DXd and T-DM1 groups, respectively, representing an absolute improvement in ORR of 45% with T-DXd Findings were consistent across all patient subgroups, with the absolute improvement in ORR associated with T-DXd relative to T-DM1 ranging from 39% to 52%.

In the trastuzumab deruxtecan group (N=119), confirmed disease control rate=86.00% (95% Cl 78.00-91.00%), median Duration of Response (mDOR)=11.30 months (95% Cl 5.60-not estimable), median overall survival (mOS)=12.50 months (95% Cl 9.60-14.30), estimated overall survival was 80.00% at 6 months and 52.00% at 12 months, median progression-free survival (mPFS)=5.60 months (95% CI, 4.30-6.90), estimated progression-free survival=43.00% at 6 months and 30.00% at 12 months In the chemotherapy group (N=56), confirmed disease control rate=62.00% (95% Cl 49.00-75.00%), median Duration of Response (mDOR)=3.90 months (95% Cl 3.0-4.9), median overall survival (mOS)=8.40 months (95% Cl 6.90-10.70), estimated overall survival was 66.00% at 6 months and 29.00% at 12 months, median progression-free survival (mPFS)=3.50 months (95% CI, 2.00-4.30), estimated progression-free survival=21.00% at 6 months and 0.00% at 12 months.

Disease-control rate was 97.30% (95% CI, 93.80-99.10), Median Duration of Response (months)=14.80 (95% CI, 13.80-16.90), clinical-benefit rate was 76.10% (95% CI, 69.30-82.10), median duration of progression-free survival was 16.40 months (95% CI, 12.70-not reached), estimated overall survival was 93.90% (95% CI, 89.30-96.60) at 6 months and 86.20% (95% CI, 79.80-90.70) at 12 months.

In the ITT population (n=15 patients), intracranial response rate by RANO-BM was 73.33% (95% CI 48.10-89.10%) (11/15 patients; 2 patients in complete remission (13.33%); 9 patients in partial remission (60.00%)). In the per protocol population (PP;n=14 patients), the response rate was 78.57% (95% CI 49.20-95.30%) (11/14). Two patients had stable disease for 6 months and one patient had stable disease at first restaging and progressed after four cycles of trastuzumab deruxtecan. Clinical benefit rate was 13/14 (92.86%; 95% CI 66.10-99.80%) in the PP population.

In patients with extracranial metastases at baseline (n=13), a partial response by RECIST 11 was observed in 5/13 (27.8%; 95% CI 13.9-68.4%) patients, with the remainder having stable disease. None of the patients progressing on trastuzumab deruxtecan had extracranial progression as the first site of progressive disease In patients with measurable extracranial disease at baseline (n=8), a partial remission was observed in 5/8 (62.50%; 95% CI 24.50-91.50%) patients, with the remainder having stable disease.

The antitumor activity of DS-8201a was evaluated in various patient-derived xenograft models with different HER2 expression levels. Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 3 mg/kg or 10 mg/kg DS-8201a was i.v. respectively to the tumor-bearing mice.

The antitumor activity of DS-8201a was evaluated in various patient-derived xenograft models with different HER2 expression levels. Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 10 mg/kg DS-8201a was i.v. to the tumor-bearing mice.

The antitumor activity of DS-8201a was evaluated in various patient-derived xenograft models with different HER2 expression levels. Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 10 mg/kg DS-8201a was i.v. to the tumor-bearing mice.

The antitumor activity of DS-8201a was evaluated in various patient-derived xenograft models with different HER2 expression levels. Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 10 mg/kg DS-8201a was i.v. to the tumor-bearing mice.

The antitumor activity of DS-8201a and trastuzumab were evaluated in various mice xenograft models with different HER2 expression levels; CFPAC-1 (low-expression). Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 1 mg/kg DS-8201a or 10 mg/kg trastuzumab was i.v. to the tumor-bearing mice.

The antitumor activity of DS-8201a was evaluated in various mice xenograft models with different HER2 expression levels; GCIY (negative). Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 10 mg/kg DS-8201a or Anti-HER2 ADC(same drug-linker as DS-8201a and DAR=3.4) was i.v. to the tumor-bearing mice.

The in vivo antitumor activity of DS-8201a was evaluated in a HER2-positive NCI-N87 xenograft model. Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice. The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0 In this group, 0.25 mg/kg DS-8201a was iv to the tumor-bearing mice.

The antitumor activity of DS-8201a was evaluated in various mice xenograft models with different HER2 expression levels; JIMT-1 (moderate positive). Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 10 mg/kg DS-8201a or Anti-HER2 ADC(same drug-linker as DS-8201a and DAR=3.4) was i.v. to the tumor-bearing mice.

The antitumor activity of DS-8201a was evaluated in various mice xenograft models with different HER2 expression levels; Capan-1 (weak positive). Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 10 mg/kg DS-8201a or Anti-HER2 ADC(same drug-linker as DS-8201a and DAR=3.4) was i.v. to the tumor-bearing mice.

The in vivo antitumor activity of DS-8201a was evaluated in a HER2-positive NCI-N87 xenograft model. Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice. The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0 In this group, 0.5 mg/kg DS-8201a was iv to the tumor-bearing mice.

The in vivo antitumor activity of DS-8201a was evaluated in a HER2-positive NCI-N87 xenograft model. Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 1 mg/kg DS-8201a was i.v. to the tumor-bearing mice.

The antitumor activity of DS-8201a was evaluated in various mice xenograft models with different HER2 expression levels; KPL-4 (strong positive). Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 10 mg/kg DS-8201a or Anti-HER2 ADC(same drug-linker as DS-8201a and DAR=3.4) was i.v. to the tumor-bearing mice.

The in vivo antitumor activity of DS-8201a was evaluated in a HER2-positive NCI-N87 xenograft model. Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 2 mg/kg DS-8201a was i.v. to the tumor-bearing mice.

The in vivo antitumor activity of DS-8201a was evaluated in a HER2-positive NCI-N87 xenograft model. Each cell suspension or tumor fragment was inoculated subcutaneously into specific pathogen-free female nude mice.The tumor-bearing mice were randomized into treatment and control groups based on the tumor volumes, and dosing was initiated on day 0. In this group, 4 mg/kg DS-8201a was i.v. to the tumor-bearing mice.

A phase 3, randomised, open-label, multicentre, global study of datopotamab deruxtecan (Dato-DXd) in combination with durvalumab and carboplatin versus pembrolizumab in combination with platinum-based chemotherapy for the first-line treatment of patients with locally advanced or metastatic NSCLC without actionable genomic alterations (D926NC00001; AVANZAR).

A phase 3 open-label, randomised study of datopotamab deruxtecan (DatoDXd) with or without durvalumab versus investigator's choice of therapy in patients with stage i-2i triple-negative breast cancer who have residual invasive disease in the breast and/or axillary lymph nodes at surgical resection following neoadjuvant systemic therapy (TROPION-Breast03).

Dato-DXd was intravenously administered at 10 mg/kg to NCI-N87 xenograft model mice. When the tumor volume reached approximately 150-300 mm³,the tumor-bearing mice were assigned to the vehicle control group,the treatment groups and the satellite sampling groups,and Dato-DXd or other test substances were administered intravenously once on day 0.

In dose escalation phase, pts with metastatic or unresectable non-small cell lung cancer (NSCLC) with EGFR activating mutation after disease progression during/after EGFR TKI therapy; In Dose Expansion phase, pts with metastatic or unresectable NSCLC with EGFR activating mutation or squamous or non-squamous NSCLC with disease progression during/after systemic treatment for locally advanced or metastatic disease.

PDX studies CTG-2093, CTG-0166, CTG-0820, and CTG-1061 studies were performed by Champions Oncology, Inc. Models were established by inoculating tumor fragments derived from patients with small cell lung cancer (SCLC), nonsmall cell lung cancer (NSCLC), head and neck cancer, and bladder cancer, respectively, which were maintained in host mice, subcutaneously into female Hsd: Athymic Nude-Foxn1nu mice.Group assignment was carried out when the tumor volume reached approximately 100 to 300 mm³. The tumor-bearing mice were treated with DS-7300a or relevant controls intravenously on days 0 and 14.

Serial dilutions of ADCs in cell culture media were prepared at 4x working concentrations, and 50 uL of each dilution was added to the 96-well plates. Following addition of test articles, cells were incubated for 4 days at 37°C, after which growth inhibition was assessed by the addition of CellTiter-Glo and luminescence was measured on a plate reader.

Serial dilutions of ADCs in cell culture media were prepared at 4x working concentrations, and 50 uL of each dilution was added to the 96-well plates. Following addition of test articles, cells were incubated for 4 days at 37°C, after which growth inhibition was assessed by the addition of CellTiter-Glo and luminescence was measured on a plate reader.

Serial dilutions of ADCs in cell culture media were prepared at 4x working concentrations, and 50 uL of each dilution was added to the 96-well plates. Following addition of test articles, cells were incubated for 4 days at 37°C, after which growth inhibition was assessed by the addition of CellTiter-Glo and luminescence was measured on a plate reader.

Serial dilutions of ADCs in cell culture media were prepared at 4x working concentrations, and 50 uL of each dilution was added to the 96-well plates. Following addition of test articles, cells were incubated for 4 days at 37°C, after which growth inhibition was assessed by the addition of CellTiter-Glo and luminescence was measured on a plate reader.

Serial dilutions of ADCs in cell culture media were prepared at 4x working concentrations, and 50 uL of each dilution was added to the 96-well plates. Following addition of test articles, cells were incubated for 4 days at 37°C, after which growth inhibition was assessed by the addition of CellTiter-Glo and luminescence was measured on a plate reader.

Serial dilutions of ADCs in cell culture media were prepared at 4x working concentrations, and 50 uL of each dilution was added to the 96-well plates. Following addition of test articles, cells were incubated for 4 days at 37°C, after which growth inhibition was assessed by the addition of CellTiter-Glo and luminescence was measured on a plate reader.

Serial dilutions of ADCs in cell culture media were prepared at 4x working concentrations, and 50 uL of each dilution was added to the 96-well plates. Following addition of test articles, cells were incubated for 4 days at 37°C, after which growth inhibition was assessed by the addition of CellTiter-Glo and luminescence was measured on a plate reader.

Serial dilutions of ADCs in cell culture media were prepared at 4x working concentrations, and 50 uL of each dilution was added to the 96-well plates. Following addition of test articles, cells were incubated for 4 days at 37°C, after which growth inhibition was assessed by the addition of CellTiter-Glo and luminescence was measured on a plate reader.

Serial dilutions of ADCs in cell culture media were prepared at 4x working concentrations, and 50 uL of each dilution was added to the 96-well plates. Following addition of test articles, cells were incubated for 4 days at 37°C, after which growth inhibition was assessed by the addition of CellTiter-Glo and luminescence was measured on a plate reader.

Serial dilutions of ADCs in cell culture media were prepared at 4x working concentrations, and 50 uL of each dilution was added to the 96-well plates. Following addition of test articles, cells were incubated for 4 days at 37°C, after which growth inhibition was assessed by the addition of CellTiter-Glo and luminescence was measured on a plate reader.