This study will evaluate two study drugs called ubamatamab and REGN7075, to see if they can help treat advanced or metastatic Non-Small Cell Lung Cancer (NSCLC), and sarilumab, to evaluate to see if it can help with immune-related side effects from ubamatamab.

The study is looking at:

• How well ubamatamab and REGN7075 works
• The side effects that ubamatamab and REGN7075 might cause
• How much ubamatamab and REGN7075 is in the blood at different times
• If the body makes antibodies to ubamatamab and/or REGN7075, this may cause the ubamatamab to not work as well

Key Inclusion Criteria:

1. Has histologically or cytologically confirmed diagnosis of advanced (stage IIIB not amenable to definitive chemoradiotherapy or stage IIIC) or metastatic (stage IV) NSCLC
2. Has received appropriate first line standard of care treatment for advanced or metastatic NSCLC, as described in the protocol
3. If platinum doublet chemotherapy was not administered as first line therapy, it is required in a later line of therapy prior to enrollment unless there is a documented reason why it is not appropriate
4. Has tumor tissue (archival or fresh) available for testing MUC16 expression by immunohistochemistry inclusion (IHC), as described in the protocol
5. Has at least 1 radiographically measurable lesion by Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) per RECIST v1.1 criteria. Target lesions may be located in a previously irradiated field if there is documented (radiographic) disease progression in that site
6. Has an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1

Key Exclusion Criteria:

1. Has progression of disease fewer than 84 days from starting initial anti-Programmed Cell Death (PD)-(L) 1 therapy
2. Experienced toxicity related to prior treatment that has not resolved to grade 1 prior to initiation of study intervention (except alopecia, hearing loss, grade 2 neuropathy, or endocrinopathy managed with hormone replacement therapy)
3. Has untreated or active primary brain tumor, Central Nervous System (CNS) metastases, leptomeningeal disease, or spinal cord compression, as described in the protocol
4. Current participation OR past participation in another investigational study in which an investigational intervention (eg, drug, vaccine, invasive device) was administered within 4 weeks before planned first dose of study intervention in this clinical study
5. Has received prior monoclonal antibody against PD-(L)1 within 21 days of the first dose of study intervention
6. Has had other prior anti-cancer immunotherapy within 21 days prior to study intervention, as described in the protocol
7. Has received prior cytotoxic chemotherapy within 21 days of the first dose of study intervention
8. Has received an anti-EGFR antibody therapy within the following drug-specific window prior to first dose of study intervention (approximately 5 half-lives), as described in the protocol

NOTE: Other protocol defined inclusion / exclusion criteria apply

All Individual Patient Data (IPD) that underlie publicly available results will be considered for sharing.

When Regeneron has:

• received marketing authorization from major health authorities (e.g., FDA, European Medicines Agency (EMA), Pharmaceuticals and Medical Devices Agency (PMDA), etc.) for the product and indication or has globally discontinued development of the product for all indications on or after April 2020 and has no plans for future development
• made the study results publicly available (e.g., scientific publication, scientific conference, clinical trial registry)
• the legal authority to share the data, and
• ensured the ability to protect participant privacy

Qualified researchers can submit a proposal for access to individual patient or aggregate level data from a Regeneron-sponsored clinical trial through Vivli. Regeneron's Independent Research Request Evaluation Criteria can be found at: https://www.regeneron.com/sites/default/files/Regeneron-External-Data-Sharing-Policy-and-Independent-Research-Request-Evaluation-Criteria.pdf