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Topiramate ER

Supernus Pharmaceuticals, Inc. · Phase 1 active Small molecule ✓ Verified May 2026

Topiramate ER is a Small molecule drug developed by Supernus Pharmaceuticals, Inc.. It is currently in Phase 1 development. Also known as: SPN-538T.

Topiramate ER is a small molecule medication used to treat conditions such as Binge Eating Disorder, Obesity, Cocaine Dependence, and Polycystic Ovary Syndrome, often in combination with other medications like phentermine. It is available under the brand name Qsymia, which is an extended-release formulation of phentermine and topiramate.

Likelihood of approval
9.6% vs 9.6% industry baseline
If approved by FDA: likely 2033–2036
Steps remaining: Phase 2 → Phase 3 → NDA/BLA submission
Confidence: Medium
Why this estimate
  • Baseline phase 1 → approval rate +9.6pp
    Industry-wide phase 1 drugs reach approval ~9.6% 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 2033–2036
EMA EU 2034–2037 +0.7 yr
MHRA GB 2034–2037 +0.7 yr
Health Canada CA 2034–2038 +0.9 yr
TGA AU 2034–2038 +1.2 yr
PMDA JP 2034–2038 +1.5 yr
NMPA CN 2035–2039 +2.3 yr
MFDS KR 2034–2038 +1.4 yr
CDSCO IN 2034–2039 +1.8 yr
ANVISA BR 2035–2039 +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 nameTopiramate ER
Also known asSPN-538T
SponsorSupernus Pharmaceuticals, Inc.
ModalitySmall molecule
PhasePhase 1

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 Topiramate ER

What is Topiramate ER?

Topiramate ER is a Small molecule drug developed by Supernus Pharmaceuticals, Inc..

Who makes Topiramate ER?

Topiramate ER is developed by Supernus Pharmaceuticals, Inc. (see full Supernus Pharmaceuticals, Inc. pipeline at /company/supernus-pharmaceuticals-inc).

Is Topiramate ER also known as anything else?

Topiramate ER is also known as SPN-538T.

What development phase is Topiramate ER in?

Topiramate ER is in Phase 1.

Related

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