A Study of Subcutaneous (SC) Pembrolizumab Coformulated With Berahyaluronidase Alfa (MK-3475A) vs Intravenous Pembrolizumab in Adult Participants With Metastatic Non-small Cell Lung Cancer (NSCLC) (MK-3475A-D77)-Japan Extension

A Phase 3 Randomized, Open-label Clinical Study to Evaluate the Pharmacokinetics and Safety of Subcutaneous Pembrolizumab Coformulated With Hyaluronidase (MK-3475A) Versus Intravenous Pembrolizumab, Administered With Chemotherapy, in the First-line Treatment of Participants With Metastatic Non-small Cell Lung Cancer

This study is to assess the pharmacokinetics (PK) and safety of SC pembrolizumab (+) berahyaluronidase alfa vs intravenous (IV) pembrolizumab, administered with chemotherapy in first line treatment of adult Japanese participants with metastatic non-small cell lung cancer. The primary hypotheses of this study are pembrolizumab (+) berahyaluronidase alfa subcutaneous (SC) is noninferior to pembrolizumab IV with respect to PK parameters.

Japan extension study will require approximately six years which includes one additional year (beyond the global study's last participant last study related contact) from the time the first participant (or their legally acceptable representative) provides informed consent until the last participant's last study related contact to complete.

The Japan extension study will include participants previously enrolled in Japan in the global study for MK-3475A-D77 (NCT05722015) plus the study will continue to enroll participants in Japan until the sample size for participants in Japan reaches approximately 39.

As of Amendment 1 of the supplemental statistical analysis plan (effective date: 23 Aug 2024), patient reported outcomes will no longer be the secondary outcome measures of the study.

Effective as of Amendment 4, participants will no longer be able to start a second course of pembrolizumab. Participants already receiving second course treatment at the time of amendment 4 should continue to receive second course treatment.

The key inclusion and exclusion criteria include but are not limited to the following:

Inclusion Criteria:

• Has histologically or cytologically confirmed diagnosis of squamous or non-squamous Non-small Cell Lung Cancer (NSCLC)
• Must provide archival tumor tissue sample or newly obtained core, incisional, or excisional biopsy of a tumor lesion not previously irradiated
• Has a life expectancy of at least 3 months

Exclusion Criteria:

• Has a diagnosis of small cell lung cancer or, for mixed tumors, presence of small cell elements
• Has received prior systemic anticancer therapy for metastatic NSCLC
• Has received prior systemic anticancer therapy including investigational agents within 4 weeks before randomization
• Has received prior radiotherapy within 2 weeks of start of study intervention or has radiation-related toxicity requiring corticosteroids
• Has received radiation therapy to the lung (>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 a diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy
• Has a known additional malignancy that is progressing or has required active treatment within the past 3 years
• Has an active autoimmune disease that has required systemic treatment in past 2 years
• Has an active infection requiring systemic therapy
• Has a history of human immunodeficiency virus (HIV) infection
• Has a history of Hepatitis B or C
• Has not adequately recovered from major surgery or has ongoing surgical complications
• Has a history of allogenic tissue/solid organ transplant