Pharmacokinetics and safety of tryptophan.

Pharmacokinetics and safety of tryptophan as a novel immune cell activator targeting kynurenine metabolism.

Status

Active, not recruiting

Phases

Phase 1

Study type

Interventional

Source

JPRN

Registry ID

JPRN-jRCTs041220025

Enrollment

Registered

2022-05-31

Start date

2022-05-31

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

healthy volunteer

Interventions

Tryptophan dosing

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: - Has provided written consent for participation - Age 20 or greater at the time of consent

Exclusion criteria

Exclusion criteria: - Pregnant or possibly pregnant women - Lactating women - With a history of hypersensitivity to tryptophan supplements - Taking medications that act on serotonergic nervons - Presence or history of psychiatric disease - Presence of serious hepatic or renal impairment - Deemed ineligible for the study as determined by the principal investigator or a co-investigator

Design outcomes

Primary

Measure	Time frame
Changes in blood concentrations of tryptophan and related metabolites	—

Secondary

Measure	Time frame
Safety	—

Contacts

Public ContactTakenao Koseki

Fujita Health University

aca-rspf@fujita-hu.ac.jp+81-562-93-9407

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026