For Healthcare Professionals

Study of Durvalumab + Tremelimumab With Chemotherapy or Durvalumab With Chemotherapy or Chemotherapy Alone for Patients With Lung Cancer (POSEIDON).


About the study

This is a randomized, open-label, multi-center, global, Phase III study to determine the efficacy and safety of durvalumab + tremelimumab combination therapy + Standard of care (SoC) chemotherapy or durvalumab monotherapy + SoC chemotherapy versus SoC chemotherapy alone as first line treatment in patients with metastatic non small-cell lung cancer (NSCLC) with tumors that lack activating epidermal growth factor receptor (EGFR) mutations and anaplastic lymphoma kinase (ALK) fusions.

Who can take part

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


Inclusion Criteria:

For inclusion in the study, patients should fulfill the following criteria:

  1. Aged at least 18 years.
  2. Histologically or cytologically documented Stage IV NSCLC.
  3. Confirmed tumor PD-L1 status prior to randomization.
  4. Patients must have tumors that lack activating EGFR mutations and ALK fusions.
  5. No prior chemotherapy or any other systemic therapy for metastatic NSCLC.
  6. World Health Organization (WHO)/Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
  7. No prior exposure to immunemediated therapy, excluding therapeutic anticancer vaccines.


Exclusion Criteria:

Patients should not enter the study if any of the following exclusion criteria are fulfilled:

  1. Mixed small-cell lung cancer and NSCLC histology, sarcomatoid variant.
  2. Active or prior documented autoimmune or inflammatory disorders.
  3. Brain metastases or spinal cord compression unless the patient's condition is stable and off steroids.
  4. Active infection including tuberculosis, hepatitis B, hepatitis C, or human immunodeficiency virus.

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


Non Small Cell Lung Cancer NSCLC

Age (in years)

18 - 130


Phase 3

Participants needed


Est. Completion Date

May 28, 2025

Treatment type



AstraZeneca identifier


Study number


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