For Healthcare Professionals

A Study Evaluating DS-1055a in Participants With Relapsed or Refractory Locally Advanced or Metastatic Solid Tumors


About the study

The purpose of this study is to assess the safety and tolerability of DS-1055a in participants with relapsed or refractory locally advanced or metastatic solid tumors for which no standard treatment is available.

Who can take part

You may be eligible to participate in the study if you meet the following criteria:


Inclusion Criteria:

  1. Has a histopathologically documented locally advanced or metastatic head and neck, gastric, esophageal cancer, non-small cell lung cancer, or melanoma. Participants with other types of solid tumors may be eligible following discussion with the Sponsor.
  2. Has a relapsed or refractory disease that is not amenable to curative standard therapy.
  3. Is 18 years of age or older.
  4. Has an Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0-1, with no deterioration for two weeks.
  5. Has a measurable disease based on Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1.
  6. Has adequate organ function within 7 days before enrollment.
  7. Is able to provide written informed consent and is willing and able to comply with the protocol.


Exclusion Criteria:

  1. Has a concurrently active second malignancy, other than adequately treated non-melanoma skin cancers, in situ melanoma or in situ cervical cancer. Participants with history of the second malignancy have been disease-free for <3 years.
  2. Has a history of (non-infectious) interstitial lung disease (ILD) that required steroids, currently has ILD, or when suspected ILD cannot be ruled out by imaging at screening.
  3. Has a history of severe pulmonary compromise or requirement of supplemental oxygen within 6 months before enrollment.
  4. Has active hepatitis B or hepatitis C virus infection.
  5. Has received prior immunotherapy with a Grade 3 or higher, or any unresolved ≥Grade 2 immune-related adverse event.
pin location

Study Locations

Enter your ZIP code/Postal code/PIN code to locate study sites near you:

How to Apply

Contact the study center to learn if this study is a good match for you.

Study’s details


Solid Tumor,Advanced Cancer,Metastatic Solid Tumor

Age (in years)



Phase 1

Participants needed


Est. Completion Date

Dec 31, 2024

Treatment type



Daiichi Sankyo, Inc. identifier


Study number


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