Researchers are investigating new treatments for untreated advanced non-small cell lung cancer (NSCLC), which is the most common form of lung cancer and lung cancer that has spread beyond surgical removal. Standard treatments include immunotherapy, such as pembrolizumab, and chemotherapy. This study aims to determine the effectiveness of adding other treatments, including the human epidermal growth factor receptor 3-directed antibody-drug conjugate (HER3-DXd) patritumab deruxtecan, to pembrolizumab, with or without chemotherapy. The primary goals are to assess safety and efficacy of the treatments.

Inclusion Criteria:

The main inclusion criteria include but are not limited to the following:

• Histologically or cytologically confirmed diagnosis of Stage IV squamous or non-squamous non-small cell lung cancer (NSCLC) per American Joint Committee on Cancer (AJCC) Staging Manual Version 8.
• Has an Eastern Cooperative Oncology Group (ECOG) performance status of either 0 or 1 as assessed within 7 days before randomization.
• Has archival tumor tissue sample or newly obtained core, incisional, or excisional biopsy of a tumor lesion not previously irradiated has been provided.
• Human immunodeficiency virus (HIV)-infected participants must have well controlled HIV on ART.
• Participants who are hepatitis B surface antigen (HBsAg) positive are eligible if they have received hepatitis B virus (HBV) antiviral therapy for at least 4 weeks and have undetectable HBV viral load prior to treatment randomization.

Exclusion Criteria:

The main exclusion criteria include but are not limited to the following:

• Has a diagnosis of small cell lung cancer or, for mixed tumors, presence of small cell elements.
• Participants with squamous histology are excluded if there is a known tumor-activating epidermal growth factor receptor (EGFR) mutation or anaplastic lymphoma kinase (ALK) or c ros oncogene 1 (ROS1) gene rearrangement.
• Is HIV-infected with a history of Kaposi's sarcoma and/or Multicentric Castleman's Disease
• Clinically severe pulmonary compromise resulting from intercurrent pulmonary illnesses including, but not limited to, any underlying pulmonary disorder, or any autoimmune, connective tissue, or inflammatory disorders with pulmonary involvement.
• Has evidence of any leptomeningeal disease.
• Has known history of, or active, neurologic paraneoplastic syndrome.
• Has clinically significant corneal disease.
• Has myocardial infarction within 6 months.
• Has New York Heart Association (NYHA) Classes 3 or 4 congestive heart failure.
• Has uncontrolled angina pectoris within 6 months.
• Has cardiac arrhythmia requiring ongoing antiarrhythmic treatment.
• Has history of clinically relevant ventricular arrhythmias, such as ventricular tachycardia, ventricular fibrillation, or Torsade de Pointes.
• Has bradycardia of less than 50 beats per minute (bpm) unless the participant has a pacemaker.
• Has history of second- or third-degree heart block. Candidates with a history of heart block may be eligible if they currently have pacemakers and have no history of fainting or clinically relevant arrhythmia with pacemakers.
• Has coronary/peripheral artery bypass graft within 6 months.
• Has complete left bundle branch block.
• Has inadequate washout period from prior concomitant therapy as specified in protocol before randomization.
• Has received prior treatment with a topoisomerase I inhibitor or an anti-HER3 antibody and/or ADC that consists of an exatecan derivative that is a topoisomerase I inhibitor.
• Has received prior systemic anticancer therapy for their metastatic NSCLC.
• Has received prior therapy with an anti- programmed cell death 1 protein (anti-PD-1), anti- programmed cell death ligand 1 protein (anti-PD-L1), or anti- programmed cell death ligand 2 protein (anti-PD-L2) agent, or with an agent directed to another stimulatory or coinhibitory T-cell receptor.
• Has received prior radiotherapy within 2 weeks of randomization, has radiation related toxicity requiring corticosteroids, or has had radiation pneumonitis.
• Has received radiation therapy to the lung that is >30 gray within 6 months of start of study intervention.
• Has received a live or live-attenuated vaccine within 30 days before the first dose of study intervention.
• Has diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to the first dose of study intervention.
• Has known additional malignancy that is progressing or has required active treatment within the past 3 years.
• Has known active central nervous system (CNS) metastases and/or carcinomatous meningitis.
• Has severe hypersensitivity to any of the study interventions and/or any of their excipients.
• Has active autoimmune disease that has required systemic treatment in the past 2 years.
• Has active infection requiring systemic therapy.
• Has concurrent active Hepatitis B and Hepatitis C virus infection.
• Have not adequately recovered from major surgery or have ongoing surgical complications.

https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf