Phase 2, Single-arm, Open-label Study of DS-1062a in Advanced or Metastatic Non-small Cell Lung Cancer with Actionable Genomic Alterations and Progressed On or After Applicable Targeted Therapy and Platinum-based Chemotherapy (TROPION-Lung05)

This is a study of the efficacy, pharmacokinetics, and safety of DS-1062a in participants
with advanced or metastatic non-small cell lung cancer (NSCLC) with known actionable genomic
alterations.

Inclusion Criteria:

Participants eligible for inclusion in the study must meet all inclusion criteria for this
study.

- Sign and date the inform consent form (ICF) prior to the start of any study- specific
qualification procedures.

- Adults ≥18 years (if the legal age of consent is >18 years old, then follow local
regulatory requirements)

- Has pathologically documented NSCLC that:

1. Has stage IIIB, IIIC, or stage IV NSCLC disease at the time of enrollment (based
on the American Joint Committee on Cancer, Eighth Edition).

2. Has one or more of the following documented activating genomic alterations: EGFR,
ALK, ROS1, NTRK, BRAF, MET exon 14 skipping, or RET.

KRAS mutations in the absence of any of the genomic alterations specified above will be
excluded.

Overexpression of EGFR, in the absence of activating mutations, is NOT sufficient for
enrollment.

Participants who have not received osimertinib should be evaluated for the presence of EGFR
T790M mutation after relapse/progression on/after the most recent EGFR tyrosine kinase
inhibitor (TKI), unless the participant is already known to be positive with document
results for this mutation or unless osimertinib is not locally approved.

- Has documentation of radiographic disease progression while on or after receiving the
most recent treatment regimen for advanced or metastatic NSCLC.

- Participant must meet the following for advanced or metastatic NSCLC:

1. Has been treated with at least one but no more than two cytotoxic
agent-containing therapy in the metastatic setting:

- One platinum-containing regimen (either as monotherapy or combination
therapy).

- May have received up to one additional line of cytotoxic agent-containing
therapy.

- Those who received a platinum-containing regimen as adjuvant therapy for
early stage disease must have relapsed or progressed while on the treatment
or within 6 months of the last dose OR received at least one additional
course of platinum-containing therapy (which may or may not be same as in
the adjuvant setting) for relapsed/progressive disease.

2. May have received up to one checkpoint inhibitor (CPI)-containing regimen (may be
in combination with a cytotoxic agent as part of a regimen described above or as
an additional CPI regimen without a cytotoxic agent).

3. Has been treated with 1 or more lines of non-CPI targeted therapy that is locally
approved for the participant's applicable genomic alteration at the time of
screening:

- Those who received a targeted agent for the applicable genomic alterations
in the study as adjuvant therapy for early stage disease must have relapsed
or progressed while on the treatment or within 6 months of the last dose OR
received at least one additional course of targeted therapy for the same
genomic alterations (which may or may not be same agent used in the adjuvant
setting) for relapsed/progressive disease.

- Participants who have been treated with a prior TKI must receive additional
targeted therapy, if clinically appropriate, for the genomic alterations
that are considered amenable or the participant will not be allowed in the
study.

- Must undergo a mandatory pre-treatment tumor biopsy procedure or if available, a tumor
biopsy that was recently collected (within 3 months of screening) after completion of
the most recent anticancer treatment regimen and that has a minimum of 10 × 4 micron
sections or a tissue block equivalent of 10 × 4 micron sections may be substituted for
the mandatory biopsy collected during screening.

- Measurable disease based on local imaging assessment using RECIST v1.1.

- Eastern Cooperative Oncology Group performance status (ECOG PS) of 0 - 1 at screening.

Exclusion Criteria:

Participants meeting any exclusion criteria for this study will be excluded from this
study.

- Has spinal cord compression or clinically active central nervous system metastases,
defined as untreated and symptomatic, or requiring therapy with corticosteroids or
anticonvulsants to control associated symptoms. Participants with clinically inactive
brain metastases may be included in the study.

- Has leptomeningeal carcinomatosis.

- Has prior treatment with:

1. Any chemotherapeutic agent targeting topoisomerase I, including antibody drug
conjugate (ADC) containing such agent.

2. TROP2-targeted therapy.

- Uncontrolled or significant cardiovascular disease:

1. History of myocardial infarction within 6 months prior to Cycle 1 Day 1.

2. History of uncontrolled angina pectoris within 6 months prior to Cycle 1 Day 1.

3. Symptomatic congestive heart failure (CHF) (New York Heart Association Class II
to IV) at screening. Participants with a history of Class II to IV CHF prior to
screening must have returned to Class I CHF and have LVEF ≥50% (by either an ECHO
or MUGA scan within 28 days of Cycle 1 Day 1) in order to be eligible.

4. History of serious cardiac arrhythmia requiring treatment.

5. LVEF <50% or institutional lower limit of normal by ECHO or MUGA scan.

6. Uncontrolled hypertension (resting systolic blood pressure >180 mmHg or diastolic
blood pressure >110 mmHg).

- Has a history of (non-infectious) interstitial lung disease (ILD)/pneumonitis that
required steroids, has current ILD/pneumonitis, or where suspected ILD/pneumonitis
cannot be ruled out by imaging at screening.

- Clinically severe pulmonary compromise resulting from intercurrent pulmonary illnesses

- Clinically significant corneal disease.

- Has other primary malignancies, except adequately resected non-melanoma skin cancer,
curatively treated in situ disease, or other solid tumors curatively treated, with no
evidence of disease for ≥3 years.