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Allopregnanolone

University of Arizona · Phase 2 active Small molecule ✓ Verified Jun 2026

Allopregnanolone is a Small molecule drug developed by University of Arizona. It is currently in Phase 2 development. Also known as: Allo, 3α,5α-tetrahydroprogesterone, 3α-hydroxy-5α-pregnan-20-one, Product L (allopregnanolone intravenous solution, low dose).

Allopregnanolone is a naturally occurring neurosteroid derived from progesterone, and it has been studied as a potential treatment for various conditions, including traumatic brain injury, posttraumatic epilepsy, depression, and menstrual migraine. As a medication, allopregnanolone is known as brexanolone and has been used to treat postpartum depression through intravenous injection.

Likelihood of approval
15.3% vs 15.3% industry baseline
If approved by FDA: likely 2031–2034
Steps remaining: Phase 3 → NDA/BLA submission
Confidence: Medium
Why this estimate
  • Baseline phase 2 → approval rate +15.3pp
    Industry-wide phase 2 drugs reach approval ~15.3% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas).
Predicted approval windows by jurisdiction (conditional on FDA approval)
Regulator Country Likely year Lag vs FDA
FDA US 2031–2034
EMA EU 2032–2035 +0.7 yr
MHRA GB 2032–2035 +0.7 yr
Health Canada CA 2032–2036 +0.9 yr
TGA AU 2032–2036 +1.2 yr
PMDA JP 2032–2036 +1.5 yr
NMPA CN 2033–2037 +2.3 yr
MFDS KR 2032–2036 +1.4 yr
CDSCO IN 2032–2037 +1.8 yr
ANVISA BR 2033–2037 +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 nameAllopregnanolone
Also known asAllo, 3α,5α-tetrahydroprogesterone, 3α-hydroxy-5α-pregnan-20-one, Product L (allopregnanolone intravenous solution, low dose), Product H (allopregnanolone intravenous solution, high dose)
SponsorUniversity of Arizona
ModalitySmall molecule
Therapeutic areaOther
PhasePhase 2

Approved indications

No approved indications tracked.

Common side effects

No common side effects on file.

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 Allopregnanolone

What is Allopregnanolone?

Allopregnanolone is a Small molecule drug developed by University of Arizona.

Who makes Allopregnanolone?

Allopregnanolone is developed by University of Arizona (see full University of Arizona pipeline at /company/university-of-arizona).

Is Allopregnanolone also known as anything else?

Allopregnanolone is also known as Allo, 3α,5α-tetrahydroprogesterone, 3α-hydroxy-5α-pregnan-20-one, Product L (allopregnanolone intravenous solution, low dose), Product H (allopregnanolone intravenous solution, high dose).

What development phase is Allopregnanolone in?

Allopregnanolone is in Phase 2.

Related

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