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WHEL-C-157 · Moderate evidence · 7/10

Vitex agnus-castus for PMDD

Two systematic reviews of clinical trials report that Vitex agnus-castus extracts are consistently superior to placebo and comparators for PMS/PMDD symptoms, with all reviewed studies positive.

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 7 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 headline7.0 / 10 · Moderate

Scored for women. Evidence generated in women (female population, ~100% female). (band F1, ×1.00).

Corroboration

Evidence comes from two systematic reviews of clinical trials (claims 1-7), not independent primary studies replicated separately. While the reviews collectively cite eight positive trials, the substrate counts pooled trials inside reviews as non-independent; two syntheses reach 1, not the 2 reserved for three+ truly independent studies or one large low-bias RCT.

1 / 2

Rigor

The sources are systematic reviews of clinical trials ('seven of eight trials found Vitex extracts to be superior to placebo'; 'all eight studies were positive'), which qualify as high-rigor designs (meta-analysis/systematic review of RCTs).

2 / 2

Specificity

Both PMDD and Vitex agnus-castus are named directly ('benefits for Vitex extracts in the treatment of...premenstrual dysphoric disorder'; 'VAC extract is a safe and efficacious alternative...for the treatment of PMS/PMDD symptoms').

2 / 2

Plausibility

No mechanism for how Vitex acts on PMDD is described in any claim; the claims report only clinical outcomes (superiority to placebo, pyridoxine, magnesium oxide) without any biological pathway, asserted or evidenced.

0 / 2

Consistency

Results are highly consistent in direction: seven of eight trials found Vitex superior to placebo and all eight studies were positive for PMS/PMDD ('all eight studies were positive for VAC'), with consistent superiority over multiple comparators.

2 / 2
How the scoring rubric works, in general →

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.

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 →
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