A Phase II, Multicenter, Open-label Study to Evaluate the Efficacy and Safety of Trastuzumab Deruxtecan (T-DXd, DS-8201a) for the Treatment of Selected HER2-Expressing Tumors (DESTINY-PanTumor02)

This is an open-label, multi-center, multi-cohort, Phase 2 study to evaluate the efficacy and
safety of trastuzumab deruxtecan (T-DXd) for the treatment of selected HER2-expressing
tumors.

This study will enroll 7 cohorts: urothelial bladder cancer, biliary tract cancer, cervical
cancer, endometrial cancer, ovarian cancer, pancreatic cancer, and rare tumors.

Study hypothesis: Trastuzumab deruxtecan will show meaningful clinical activity and a
favorable risk benefit profile in selected HER2-expressing solid tumors.

Inclusion Criteria:

- Locally advanced, unresectable, or metastatic disease based on most recent imaging.

- The respective cohorts for patient inclusion are:

- Cohort 1: Biliary tract cancer

- Cohort 2: Bladder cancer

- Cohort 3: Cervical cancer

- Cohort 4: Endometrial cancer

- Cohort 5: Epithelial ovarian cancer

- Cohort 6: Pancreatic cancer

- Cohort 7: Rare tumors: This cohort will consist of patients with tumors that
express HER2, excluding the tumors mentioned above, and breast, non-small cell
lung cancer, gastric cancer, and colorectal cancer.

- Progressed following prior treatment or who have no satisfactory alternative treatment
option.

- Prior HER2 targeting therapy is permitted.

- HER2 expression for eligibility may be based on local or central assessment.

- Has measurable target disease assessed by the Investigator based on RECIST version
1.1.

- Has protocol- defined adequate organ function including cardiac, renal and hepatic
function.

Exclusion Criteria:

- History of non-infectious pneumonitis/ILD that required steroids, current ILD, or
where suspected ILD that cannot be ruled out by imaging at screening

- Lung-specific intercurrent clinically significant severe illnesses

- Uncontrolled infection requiring intravenous (IV) antibiotics, antivirals, or
antifungals

- Pleural effusion, ascites or pericardial effusion that requires drainage, peritoneal
shunt, or Cell-free and Concentrated Ascites Reinfusion Therapy (CART

- Known Somatic DNA mutation of HER2 (ERBB2) without tumoral HER2 protein expression.

- Primary diagnosis of adenocarcinoma of the breast, adenocarcinoma of the colon or
rectum, adenocarcinoma of the gastric body or gastro-esophageal junction, or non-small
cell lung cancer.

- Medical conditions that may interfere with the subject's participation in the study.