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L-tryptophan supplementation

University of Colorado, Denver · Phase 3 active Small molecule

L-tryptophan supplementation is a Amino acid supplement Small molecule drug developed by University of Colorado, Denver. It is currently in Phase 3 development for Depression or mood disorders, Sleep disorders, Anxiety disorders. Also known as: L-tryptophan 1 gm PO TID starting the evening of surgery.

L-tryptophan supplementation increases the availability of tryptophan, an essential amino acid that serves as a precursor for serotonin and other neurotransmitters.

L-tryptophan supplementation increases the availability of tryptophan, an essential amino acid that serves as a precursor for serotonin and other neurotransmitters. Used for Depression or mood disorders, Sleep disorders, Anxiety disorders.

Likelihood of approval
55.3% vs 58.3% industry baseline
If approved by FDA: likely 2028–2030
Steps remaining: NDA/BLA submission
Confidence: High
Why this estimate
  • Baseline phase 3 → approval rate +58.3pp
    Industry-wide phase 3 drugs reach approval ~58.3% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas).
  • CNS / neurology attrition -3.0pp
    CNS drugs have historically high Phase 3 failure rates (notably in Alzheimer disease + major depression).
Predicted approval windows by jurisdiction (conditional on FDA approval)
Regulator Country Likely year Lag vs FDA
FDA US 2028–2030
EMA EU 2029–2031 +0.7 yr
MHRA GB 2029–2031 +0.7 yr
Health Canada CA 2029–2032 +0.9 yr
TGA AU 2029–2032 +1.2 yr
PMDA JP 2029–2032 +1.5 yr
NMPA CN 2030–2033 +2.3 yr
MFDS KR 2029–2032 +1.4 yr
CDSCO IN 2029–2033 +1.8 yr
ANVISA BR 2030–2033 +2.3 yr

Hover any row for the lag rationale. Lag estimates are reduced when the drug has FDA Breakthrough or EMA PRIME designation (sponsors file globally in parallel).

Estimate based on the BIO/Informa industry phase transition rates plus per-drug modifiers for therapeutic area, sponsor type, FDA designations, mechanism, and trial design. Per-jurisdiction lags from Tufts CSDD international approval studies. Not investment, clinical or regulatory advice. Methodology: /methodology#likelihood.

At a glance

Generic nameL-tryptophan supplementation
Also known asL-tryptophan 1 gm PO TID starting the evening of surgery
SponsorUniversity of Colorado, Denver
Drug classAmino acid supplement
TargetSerotonin synthesis pathway (tryptophan hydroxylase substrate)
ModalitySmall molecule
Therapeutic areaPsychiatry/Neurology
PhasePhase 3

Mechanism of action

L-tryptophan is converted to serotonin in the brain, which regulates mood, sleep, and other neurological functions. By supplementing dietary tryptophan intake, the drug aims to enhance serotonin synthesis and improve conditions associated with serotonin deficiency. This mechanism may also involve effects on other tryptophan metabolites such as kynurenine pathway products.

Approved indications

Common side effects

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

Frequently asked questions about L-tryptophan supplementation

What is L-tryptophan supplementation?

L-tryptophan supplementation is a Amino acid supplement drug developed by University of Colorado, Denver, indicated for Depression or mood disorders, Sleep disorders, Anxiety disorders.

How does L-tryptophan supplementation work?

L-tryptophan supplementation increases the availability of tryptophan, an essential amino acid that serves as a precursor for serotonin and other neurotransmitters.

What is L-tryptophan supplementation used for?

L-tryptophan supplementation is indicated for Depression or mood disorders, Sleep disorders, Anxiety disorders.

Who makes L-tryptophan supplementation?

L-tryptophan supplementation is developed by University of Colorado, Denver (see full University of Colorado, Denver pipeline at /company/university-of-colorado-denver).

Is L-tryptophan supplementation also known as anything else?

L-tryptophan supplementation is also known as L-tryptophan 1 gm PO TID starting the evening of surgery.

What drug class is L-tryptophan supplementation in?

L-tryptophan supplementation belongs to the Amino acid supplement class. See all Amino acid supplement drugs at /class/amino-acid-supplement.

What development phase is L-tryptophan supplementation in?

L-tryptophan supplementation is in Phase 3.

What are the side effects of L-tryptophan supplementation?

Common side effects of L-tryptophan supplementation include Nausea, Headache, Drowsiness, Gastrointestinal upset.

What does L-tryptophan supplementation target?

L-tryptophan supplementation targets Serotonin synthesis pathway (tryptophan hydroxylase substrate) and is a Amino acid supplement.

Related

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing