WhelWomen's Health Evidence Lab
WHEL-C-119 · Moderate evidence · 6/10

botulinum toxin type A for vulvodynia

A state-of-the-science review notes that botulinum toxin type A 50 units for vulvodynia is supported by at least one RCT or comparative effectiveness trial, giving it the highest level of evidence among reviewed treatments.

Origin · Existing drug · repurposing candidatePathway · 505(b)(2) · existing active ingredient, new indicationEvidence arm · Direct researchEvidence supports
How to read thisThe summary above and the proposed mechanism are generated by the model from the sources it ingested, and are written as the model’s reasoning rather than established fact. Any figure quoted from MATRIX is a model-derived association score, not a clinical measurement. How far the published record backs this pair is carried by the score’s own rigor dimension and traced to verbatim sources at the foot of the page.

Hypothesized mechanism

Mechanism not yet characterized in the substrate.

This is the model’s proposed mechanism from the sources on file, not a demonstrated causal pathway. How well the published record supports it is reflected in the rigor and plausibility dimensions of the score, and traced to the verbatim sources at the foot of the page.

How the score was reached, for this pair

The composite score is the sum of five dimensions, each scored 0 to 2 by the model from the evidence on file. Below is the sub-score this specific pair received on each, with what that dimension measures. It scored 6 of 10 overall, a moderate reading, from a direct rated moderate in strength.

The model’s overall reasoning for this pair is the summary at the top of the page, and the mechanism it proposed is in the section above.

Direct research arm · anchors the headline6.0 / 10 · Moderate

Scored for women. Evidence generated in women (female population). (band F1, ×1.00).

Corroboration

The single claim derives from one review/state-of-the-science article that summarizes the existence of at least one RCT, not multiple independent corroborating studies presented here. This counts as a single synthesis source (score 1), not independent replication.

1 / 2

Rigor

The claim references that botulinum toxin type A 50 units 'had the highest level of evidence with at least one RCT or comparative effectiveness trial,' indicating RCT-level design. This qualifies for the highest rigor tier despite being relayed via a review.

2 / 2

Specificity

Both the intervention (botulinum toxin type A 50 units) and the condition (vulvodynia) are explicitly named in the quote. The claim directly concerns this drug acting on this condition.

2 / 2

Plausibility

The claim only states a level-of-evidence ranking and does not assert or describe any mechanism by which botulinum toxin type A acts on vulvodynia. No mechanistic content is provided.

0 / 2

Consistency

Only a single source/claim is provided, so directional agreement across studies cannot be assessed. Per the n/a rule, this defaults to 1 without penalty.

1 / 2
How the scoring rubric works, in general

Regulatory & development status

Where this candidate sits in the US regulatory landscape: whether the drug is already FDA-approved for vulvodynia (on-label) or approved for something else (off-label), whether the molecule is available as a generic or a single-source brand still under patent, and how far it has been studied as a therapy for this condition. Each fact is drawn from a public US source and reported beside the score; none of it is folded into the score.

This is descriptive context, not regulatory advice. It maps the landscape a 505(b)(2)route would build on (an already-approved active ingredient proposed for a new indication), but it is not a 505(b)(2) viability assessment, and says nothing about whether any particular development path is advisable. “Approved” means FDA-approved (US); approvals elsewhere are out of scope.

Approval relationship Off-label

Read from the drug’s FDA label via DailyMed, the US National Library of Medicine’s label repository. A label is only counted when it carries an FDA-approved marketing category (an NDA, ANDA, or biologic BLA); dietary supplements, homeopathics, and OTC-monograph products are not FDA-approved drugs and are excluded.

For this pair. The drug has an FDA-approved label, but for a different indication, so using it for this condition would be off-label.

Generic & patent supply Not in the Orange Book

Read from the FDA Orange Book (Approved Drug Products with Therapeutic Equivalence Evaluations), using single-ingredient products only so that patents on novel branded combination formulations are never attributed to the base molecule.

For this molecule. Absent from the Orange Book. Biologics (listed in the Purple Book instead), dietary supplements, and drugs not FDA-approved in the US do not appear here.

Clinical-trial stage, for this condition Phase 3

Read from ClinicalTrials.gov (US National Library of Medicine). A trial only counts when the drug appears as an experimental or active-comparator intervention in an interventional study of this condition; mechanistic, drug-interaction, post-marketing (Phase 4), and comparator-background uses are excluded, so this reflects the drug being tested as a therapy for vulvodynia.

For this pair. Studied in 3 qualifying interventional trials · highest stage reached Phase 3 · completed.

NCT02773641 · Phase 3 · completed
NCT02858219 · Phase 3 · completed
NCT04057755 · Phase 3 · completed
The regulatory and trial sources this status is drawn from

Layers not covered for this pair

Sex-specific pharmacokineticsNone on file

Not covered for this pair. This layer holds documented sex-specific pharmacokinetics for a limited set of drugs, and this compound is not among them yet. A blank here means the drug is not covered by the layer, not that no sex difference exists.

More on the sex-specific pharmacokinetics layer and its sources
Cycle-phase dependenceNone on file

Not covered for this pair. The cycle-phase layer is seeded for the strongest-evidence cases so far (PMDD), and this pair is not among them yet. A blank here means the pair is not covered by the layer, not that the effect was found to be phase-independent.

More on the cycle-phase layer and its sources

Source evidence · what the pipeline ingested

These are the sources the pipeline ingested to detect and score this signal, the published literature the model actually read, each tagged by study type. Where the model combined findings the claim is marked as a synthesis (S), and where the literature disagrees the contradiction is shown (!).

Every source below belongs to this signal’s evidence arm, Direct research. Whel reads each drug-condition pair through four such arms, each held to its own inclusion bar; a signal is surfaced through one of them.

  • 1Oral desipramine with 5% lidocaine cream, intravaginal diazepam tablets with intravaginal transcutaneous electric nerve stimulation (TENS), botulinum toxin type A 50 units, enoxaparin sodium subcutaneous injections, intravaginal TENS (as a single therapy), multimodal physical therapy, overnight 5% lidocaine ointment, and acupuncture had the highest level of evidence with at least one RCT or comparative effectiveness trial. PubMed · PMID 36533637

These are the verbatim sources the pipeline surfaced and read; they may not be the full published record for a pair, and the score reflects the strength and agreement of the evidence rather than its volume. The strength of these source types is what the rigor dimension of the score reads off. MATRIX, sex-specific pharmacokinetics, and cycle phase are separate layers the pipeline does not ingest, external cross-references reported beside the score, and they link to their own sources in their sections above.

The primary sources and pipelines this evidence is drawn from