A Study to See How Safe and Tolerable Different Doses of REGN13335 Are When Administered Intravenously (IV) or Subcutaneously (SC) to Healthy Adult Participants

Study Overview
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Brief Summary
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This study is researching an experimental drug called REGN13335. This is the first time that REGN13335 will be given to people. This study will enroll healthy adults. The aim of the study is to see how safe and tolerable REGN13335 is in healthy volunteers. The study is looking at several other research questions, including: What side effects may happen from taking the study drug How much study drug is present in the blood of study participants 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)

Official Title
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A Randomized, Double-Blind, Placebo-Controlled, Single Ascending Dose Study to Assess the Safety, Tolerability, and Pharmacokinetics of Intravenously or Subcutaneously Administered REGN13335, a Platelet-Derived Growth Factor-B Antagonist, in Healthy Adult Participants

Conditions
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Healthy Volunteers

Intervention / Treatment
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* Drug: REGN13335
* Drug: Matching Placebo


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Has a body mass index between 18 and 32 kg/m^2, inclusive, at the screening visit Is judged by the investigator to be in good health based on medical history, physical examination, vital sign measurements, laboratory safety tests, and electrocardiograms (ECGs) performed prior to administration of study drug (ie, screening and baseline visit) Key Exclusion Criteria: 1. History of clinically significant cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrine, hematological, psychiatric or neurological disease, as assessed by the investigator NOTE: Other Protocol Defined Inclusion / Exclusion Criteria Apply.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Sequential Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: IV Cohort 1 Low Dose<br>Randomized (6:2) to REGN13335 or placebo | Drug: REGN13335<br>* Administered intravenous (IV) or subcutaneous (SC), sequential ascending single dose<br>Drug: Matching Placebo<br>* Administered IV or SC, sequential ascending single dose<br>|
| Experimental: IV Cohort 2 Mid Dose<br>Randomized (6:2) to REGN13335 or placebo | Drug: REGN13335<br>* Administered intravenous (IV) or subcutaneous (SC), sequential ascending single dose<br>Drug: Matching Placebo<br>* Administered IV or SC, sequential ascending single dose<br>|
| Experimental: IV Cohort 3 High Dose<br>Randomized (6:2) to REGN13335 or placebo | Drug: REGN13335<br>* Administered intravenous (IV) or subcutaneous (SC), sequential ascending single dose<br>Drug: Matching Placebo<br>* Administered IV or SC, sequential ascending single dose<br>|
| Experimental: IV Cohort 4 Higher Dose<br>Randomized (6:2) to REGN13335 or placebo | Drug: REGN13335<br>* Administered intravenous (IV) or subcutaneous (SC), sequential ascending single dose<br>Drug: Matching Placebo<br>* Administered IV or SC, sequential ascending single dose<br>|
| Experimental: SC Cohort 1 Low Dose<br>Randomized (6:2) to REGN13335 or placebo | Drug: REGN13335<br>* Administered intravenous (IV) or subcutaneous (SC), sequential ascending single dose<br>Drug: Matching Placebo<br>* Administered IV or SC, sequential ascending single dose<br>|
| Experimental: SC Cohort 2 High Dose<br>Randomized (6:2) to REGN13335 or placebo | Drug: REGN13335<br>* Administered intravenous (IV) or subcutaneous (SC), sequential ascending single dose<br>Drug: Matching Placebo<br>* Administered IV or SC, sequential ascending single dose<br>|
| Experimental: IV or SC Optional Cohort 1<br>Randomized (6:2) to REGN13335 or placebo | Drug: REGN13335<br>* Administered intravenous (IV) or subcutaneous (SC), sequential ascending single dose<br>Drug: Matching Placebo<br>* Administered IV or SC, sequential ascending single dose<br>|
| Experimental: IV or SC Optional Cohort 2<br>Randomized (6:2) to REGN13335 or placebo | Drug: REGN13335<br>* Administered intravenous (IV) or subcutaneous (SC), sequential ascending single dose<br>Drug: Matching Placebo<br>* Administered IV or SC, sequential ascending single dose<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of treatment emergent adverse events (TEAE's) through the end of the study (EOS) |  | Baseline to day 113 | 
| Severity of TEAE's through the EOS |  | Baseline to day 113 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Concentrations of functional REGN13335 in plasma through the EOS visit |  | Baseline to day 113 | 
| Incidence of anti-drug antibodies (ADA) to single doses of REGN13335 over time |  | Baseline to day 113 | 
| Titer of ADA to single doses of REGN13335 over time |  | Baseline to day 113 |