A Study of T-DXd for the Treatment of Solid Tumors Harboring HER2 Activating Mutations

Inclusion Criteria:

Adults ≥18 years old. Other age restrictions may apply as per local regulations.
Unresectable and/or metastatic solid tumors with pre-specified HER2 mutations locally determined by NGS, who have progressed following prior treatment or who have no satisfactory alternative treatment options.
Prior HER2 targeted therapy is permitted.
All patients must provide an FFPE tumor sample for retrospective central HER2 testing.
LVEF ≥50%
ECOG 0-1

Exclusion Criteria:

HER2 overexpressing (IHC3+ or IHC2+/ISH+) breast, gastric or gastroesophageal junction adenocarcinoma.
HER2 mutant NSCLC.
History of non-infectious pneumonitis/ILD, current ILD, or where suspected ILD cannot be ruled out by imaging at screening
Lung-specific intercurrent clinically significant severe illnesses.
History of active primary immunodeficiency, known HIV, active HBV or HCV infection
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).
Has spinal cord compression or clinically active central nervous system metastases.