This study is researching an experimental drug called REGN7508 (called "study drug"). The aim of this study is to see how safe and tolerable the study drug is in healthy participants.

This study is looking at several other research questions, including:

• What side effects may happen from taking the study drug
• How much study drug is in the blood at different times
• Whether the body makes antibodies against the study drug (which could make the drug less effective or could lead to side effects)

Key Inclusion Criteria:

1. Body mass index between 18.0 and 32.5 kg/m2 (inclusive) at the screening visit
2. Judged by the investigator to be in good health based on medical history, physical examination, vital sign measurements, and echocardiograms (ECGs) performed at screening and/or prior to administration of initial dose of study drug
3. Participant is in good health based on laboratory safety testing obtained at the screening visit and/or prior to administration of initial dose of study drug
4. Normal activated partial thromboplastin time (aPTT), normal prothrombin time (PT), and normal platelet counts at screening period and at the day -1 visit as defined by the local laboratory
5. Hemoglobin value ≥11.0 g/dL for females and ≥12.9 g/dL for males at the screening and day 1 visits

Key Exclusion Criteria:

1. History of any major surgical procedure or clinically significant physical trauma, in the opinion of the investigator, that may pose a risk to the participant by study participation
2. Whole blood donation within the previous 56 days or plasma donation within the previous 7 days prior to the screening visit
3. History of clinically significant cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrine, hematological, psychiatric, neurological, or dermatologic disease, as assessed by the investigator, that may confound the results of the study or poses an additional risk to the participant by study participation, as defined in the protocol
4. Estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73m2 at screening
5. Current smoker or former smoker, including e-cigarettes, who stopped smoking within 12 months prior to the screening visit
6. Confirmed positive drug test result at the screening visit and/or prior to randomization or a history of drug abuse within a year prior to the screening visit
7. History of alcohol abuse within the last 2 years prior to the day 1 visit
8. Any malignancy, except for nonmelanoma skin cancer or cervical/anus in situ, that have been resected with no evidence of metastatic disease for 3 years prior to the screening visit
9. History of significant multiple and/or severe allergies (eg, latex gloves) or has had an anaphylactic reaction to prescription or nonprescription drugs or food

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, has made the study results publicly available (e.g., scientific publication, scientific conference, clinical trial registry), has the legal authority to share the data, and has 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