A Study to Investigate the Safety of AB680 in Healthy Volunteers

Study Overview
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Brief Summary
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This is a double-blind, randomized, placebo-controlled, single- and multiple-ascending dose study to investigate the safety, tolerability, and pharmacokinetic profile of AB680 in healthy volunteers.

Detailed Description
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AB680 will be administered as single and multiple intravenous doses to the healthy volunteers. In each group of 8 participants, 6 will receive AB680 and 2 will receive matching placebo. The participants will be closely observed to monitor the general tolerability of AB680.

Official Title
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A Double-Blind, Randomized, Placebo-Controlled, Single- and Multiple-Ascending Dose Study to Investigate the Safety, Tolerability, and Pharmacokinetic Profile of AB680 in Healthy Volunteers

Conditions
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Healthy Volunteers

Intervention / Treatment
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* Drug: AB680
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 to 55 years, inclusive, at screening Body mass index 18 to 30 kg/m2 Willing and able to sign informed consent Negative tests for hepatitis B surface antigen, anti-hepatitis C virus, and human immunodeficiency virus (HIV)-1 and HIV-2 antibody at screening Healthy as determined by pre-study screening Exclusion Criteria: History of clinically significant drug and/or food allergies Positive drug and alcohol screen at screening and (each) admission to the clinical research center. Participation in a drug study within 60 days prior to (the first) drug administration in the current study. Participation in more than 4 other drug studies in the 12 months prior to (the first) drug administration in the current study Participants who have significant infection or known inflammatory process on screening or admission

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 |
| --- | --- |
| Active Comparator: Active: Dose Escalation<br>Healthy volunteers will receive AB680 as a single intravenous (IV) infusion at 7 dose levels and as multiple IV infusions at 1 dose level. Assignment to receive AB680 or matching placebo will be random. | Drug: AB680<br>* AB680 is a Cluster of Differentiation (CD)73 Inhibitor<br>|
| Placebo Comparator: Placebo: Dose Escalation<br>Healthy volunteers will receive matching placebo as a single IV infusion and as multiple IV infusions. Assignment to receive AB680 or matching placebo will be random. | Other: Placebo<br>* Matching Placebo<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants with Treatment Emergent Adverse Events (TEAEs). | Number of Participants with TEAEs as Assessed by CTCAE v5.0. | From First Dose Date to 15 Days After the Last Dose of AB680. | 
| AB680 Peak Plasma Concentration (Cmax) | Cmax as Measured by the Area Under Concentration-Time Curve from Plasma Collection and Analysis. | From First Dose Date to 15 Days After the Last Dose of AB680. | 
| AB680 Time of Peak Concentration (Tmax) | Tmax as Measured by the Time to Maximum Concentration-Time Curve from Plasma Collection and Analysis. | From First Dose Date to 15 Days After the Last Dose of AB680. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pharmacodynamic (PD) Effects of AB680 | Enzymatic Activity of CD73 Measured in Participant Blood Samples. | From First Dose Date to 15 Days After the Last Dose of AB680. | 
| Plasma Levels of Adenosine | Amount of Adenosine Measured in Participant Blood Samples. | From First Dose Date to 15 Days After the Last Dose of AB680. |