Pharmacokinetic (PK) Study of Tafenoquine in Healthy Adults

NCT07373743 | Not Yet Recruiting Early Phase 1 FDA Drug

• 2 other identifiers: 2026-01-UMUPR241374
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to learn how people's different genetic makeups affects how their bodies convert the FDA approved drug ARAKODA (tafenoquine) to its active form. Tafenoquine is a drug that is taken to prevent malaria for people traveling to areas where there is malaria. This trial will be in healthy participants age 18-65.

Conditions

Pharmacokinetic in Normal Population

Keywords

Tafenoquine; CYP2D6; Pharmacokinetic

Outcome Measures

Primary Outcomes (2)

• Tafenoquine levels in blood over time

  Pre-dose, 4, 8, 12, and 24 hours (Day 2) and Days, 3, 4, 5, 6, 7, 8, 15, 22, 29, and 57.

• Tafenoquine levels in urine over time

  Pre-dose, total volume collected between 0-4, 4-8, 8-12, 12-24 hours and then single void collections on Days 3, 4, 5, 6, 7, 8, 15, 22, 29, 57.

Secondary Outcomes (4)

• Methemoglobin Levels

  Pre-dose, 4, 8, 12, and 24 hours (Day 2) and Days, 3, 4, 5, 6, 7, 8, 15, 22, 29, and 57

• Laboratory abnormalities

  Pre-dose, Day 4 and 15

• Adverse Events

  From Day 1 to Day 29

• Serious Adverse Events

  Day 1 to Day 57

Study Arms (4)

Normal Metabolizers (NM)

EXPERIMENTAL

Participants with normal CYP2D6 enzyme activity receiving a single 300 milligram (mg) dose of tafenoquine.

Drug: Tafenoquine Oral Tablet

Intermediate Metabolizers (IM)

EXPERIMENTAL

Participants with decreased activity of the enzyme leading to variable effects i.e., either no effect, increased adverse effects from TQ or reduced efficacy of the drug in endemic areas due to inadequate metabolism receiving a single 300mg dose of tafenoquine.

Drug: Tafenoquine Oral Tablet

Poor Metabolizers (PM)

EXPERIMENTAL

Participants with no enzyme activity at all, leading to a null phenotype and no drug metabolism, receiving a single 300mg dose of tafenoquine.

Drug: Tafenoquine Oral Tablet

Ultra Metabolizers (UM)

EXPERIMENTAL

Participants with increased enzyme activity, leading to accelerated metabolism, receiving 300mg dose of tafenoquine

Drug: Tafenoquine Oral Tablet

Interventions

Tafenoquine Oral Tablet DRUG

Single, 300mg dose

Intermediate Metabolizers (IM); Normal Metabolizers (NM); Poor Metabolizers (PM); Ultra Metabolizers (UM)

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18-65 at the time of consent, weighing between 132 and 250 pounds
• Ability and willingness to sign informed consent
• Available for the study period
• Willing to use contraception for the duration of the study
• Agree not to take over the counter antioxidants, vitamin C or vitamin E, 2 weeks prior to dosing and 7 days post dosing

You may not qualify if:

• Women: positive urine pregnancy test at screening or day of dosing
• Women who are lactating or intend to become pregnant during the study period.
• Acute or chronic clinically significant hematologic, pulmonary, cardiovascular, hepatic, or renal functional abnormality as determined by medical history, physical examination or laboratory screening.
• History of allergic reaction to tafenoquine or primaquine.
• Scheduled receipt of any vaccine 1 week prior to or after 4 weeks tafenoquine dosing. Routine COVID and influenza vaccination will be allowed outside of this timeframe.
• Currently taking metformin, dofeltilide or other medication with known multidrug and toxin extrusion enzyme (MATE) metabolism.
• Known or suspected congenital or acquired immunodeficiency; or receipt of immunomodulation therapy such as anti-cancer chemotherapy or radiation therapy.
• Diagnosis with Bipolar Disorder or Schizophrenia, hospitalization in the past year for a mental health disorder, or any other psychiatric condition, which in the opinion of the investigator prevents the participant from participating in the study.
• Positive HIV, hepatitis B surface antigen or hepatitis C.
• G6PD result not normal or \< 70% activity
• Significant screening physical examination abnormalities or chronic medical condition that in the opinion of the investigator may impact participant safety, including BMI \> 35kg/m2
• Participation (active or follow-up phase) or planned participation in another vaccine, or drug, in the 4 weeks prior to or during the trial
• Beliefs that bar the administration of blood products or transfusions
• Clinician discretion

Sponsors & Collaborators

• State University of New York - Upstate Medical University: lead

Study Sites (1)

SUNY Upstate Medical University, Upstate Global Health Institute

East Syracuse, New York, 13057, United States

Location

MeSH Terms

Interventions

tafenoquine

Study Officials

• Michele Spring, MD

  State University of New York - Upstate Medical University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Keely Terrillion

CONTACT

315-464-9869; trials@upstate.edu

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 16, 2026
• First Posted: January 28, 2026
• Study Start: May 1, 2026
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): March 1, 2027
• Last Updated: March 20, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will share
• Time Frame: IPD will be shared with the primary publication
• Access Criteria: Primary IPD will be published with the primary manuscript describing the study. Requests for additional information can be requested by emailing warel@upstate.edu.

Locations

US (1)