Home›Articles›An EU withdrawal's US aftershock: dirlotapide still carries 2,994 adverse-event reports

An EU withdrawal's US aftershock: dirlotapide still carries 2,994 adverse-event reports

A marketing authorisation is a legal permission tied to one jurisdiction. When that permission ends, the drug's risk profile does not reset to zero. The clearest illustration in the current veterinary dataset is dirlotapide, the active ingredient in the canine weight-loss medicine Slentrol (dirlotapide) — EMEA/V/C/000116, whose EU status is Withdrawn. Across the Atlantic, the same molecule's US adverse-event record keeps its full weight: Dirlotapide: 2994 reports in the FDA Center for Veterinary Medicine database. This article traces that gap — withdrawal in Europe, persistence in the United States — and puts the figure next to two cardiovascular comparators.

The EU withdrawal

In the EMA Union Product Database, the alimentary-tract antiobesity group lists Slentrol (dirlotapide) — EMEA/V/C/000116 with Status: Withdrawn, Species: Dogs, ATCvet code: QA08AB91, and the pharmacotherapeutic group Antiobesity preparations, excl. diet products. Its indication was As an aid in the management of overweight and obesity in adult dogs. The marketing authorisation holder is Zoetis Belgium SA. A second canine antiobesity medicine in the same QA group, Yarvitan (mitratapide) — EMEA/V/C/000113, also carries Status: Withdrawn.

These are not isolated cases. The wider EU veterinary picture, drawn from the medicines-output dataset (2,714 data rows; 393 entries are classified as Veterinary), includes other withdrawn or refused pet medicines. In the cardiovascular group, Spironolactone Ceva — EMEA/V/C/000105 carries Status: Withdrawn (Species: Dogs, Diuretics, indicated for congestive heart failure in dogs), while Lodipressin — EMEA/V/C/003786 carries Status: Refused (Species: Cats, Calcium channel blockers, indicated for systemic arterial hypertension in cats). The EMA record is explicit that neither is currently marketed in the EU under this MA number.

So the EU's centralised register tells a story of permissions closing: withdrawn authorisations, refused applications, opinions still pending. The dataset distinguishes Withdrawn / Opinion / Application withdrawn / Refused / Expired / Lapsed as medicine statuses, and the pet-relevant entries above sit firmly on the "no longer or never authorised" side.

What the US record shows

The United States measures the same molecules differently — not by marketing permission, but by what veterinarians and owners report after a product is used. The FDA CVM adverse-event database, sourced from openFDA animalandveterinary/event.json, the FDA Center for Veterinary Medicine (CVM) adverse event report database. Data pulled 2026-07-22, records the following for dirlotapide:

  • Dirlotapide: 2994
  • Dog 2807
  • Human 16
  • Cat 2

The Top reported reactions (VEDDRA terms, top entries) are stark: Vomiting 927, Anorexia 525, Depression 443, INEFFECTIVE, APPETITE SUPPRESSION 429, Diarrhoea 370, Hyperextension 328, INEFFECTIVE, WEIGHT LOSS 328, Weight gain 195, Elevated alanine aminotransferase (ALT) 180, and Polyphagia 176.

A withdrawn European authorisation does nothing to erase these reports. The US file is cumulative: it reflects everything submitted to FDA CVM up to the pull date, independent of whether the product is sold in the EU. Withdrawal in one market is a regulatory event; the adverse-event count is an epidemiological record that stays on the books.

Comparison with spironolactone and amlodipine

The same openFDA pull lets us size dirlotapide against the two cardiovascular actives named in the EU record above.

For spironolactone, the US total is Spironolactone: 297, broken down as Dog 248, Cat 22, Human 4. For amlodipine, the US total is Amlodipine: 769, broken down as Cat 378, Dog 354, Human 36.

Set against dirlotapide's 2994, the contrast is roughly an order of magnitude. Dirlotapide's US report volume is about 10× spironolactone's and nearly 4× amlodipine's — even though, in the EU, spironolactone's MA is Withdrawn and amlodipine's application was Refused. The US ADE totals do not track EU authorisation status at all: a withdrawn EU diuretic and a refused EU antihypertensive both carry far smaller US report piles than a withdrawn EU antiobesity drug.

This is the aftershock the headline points to. A molecule can be pulled from the European market and still dominate a different continent's safety-reporting ledger.

EU withdrawals versus US ADE persistence

Two systems, two lenses. The EU EMA dataset (generated 20/07/2026 - 18:00 CET) is a register of permissions: who may market what, in which species, under which ATCvet code. Its verdict on dirlotapide, mitratapide, spironolactone, and amlodipine is recorded as status — mostly Withdrawn or Refused. The US openFDA dataset, pulled 2026-07-22, is a register of experiences: what was reported after use, in which species, with which reactions. Its verdict on dirlotapide is a number — 2994 — that no European withdrawal can decrement.

The divergence matters for anyone who reads only one source. A clinician or owner who checks the EMA register sees "Withdrawn" and might assume the safety story is closed. A researcher who checks openFDA sees 2994 reports and the associated Vomiting 927, Anorexia 525, Depression 443, and liver-signal Elevated alanine aminotransferase (ALT) 180. Both are true; they answer different questions. Withdrawal answers "may this be sold here?" Persistence answers "what has been reported wherever it was used?"

Critical disclaimer: reported ≠ causal

All figures above come from a single cumulative snapshot. The ADE counts are CUMULATIVE as of openFDA pull 2026-07-22. They are report-level: one report may list multiple reactions and multiple animals, so figures are not additive and do not imply causation. In plain terms: reported ≠ causal.

The coding system behind the reactions is VEDDRA terms. Critically, several of the largest dirlotapide entries are effectiveness reports, not injuries: INEFFECTIVE, APPETITE SUPPRESSION 429 and INEFFECTIVE, WEIGHT LOSS 328 are performance complaints. As the source topics state for the comparator actives, "Lack of efficacy" terms denote product-performance reports, not adverse reactions. The same logic applies to dirlotapide's "INEFFECTIVE" entries. A high report count therefore blends suspected adverse reactions with reports that the product simply did not work as expected.

Nothing in this article should be read as establishing that dirlotapide caused any specific harm. The numbers describe what was reported to FDA CVM, not what was proven. They are a signal for further scrutiny, not a verdict.

Sources

  1. ade_dirlotapide_adverse_events — FDA openFDA animalandveterinary/event.json (FDA CVM adverse event report database), pulled 2026-07-22; source file pdf-raw/ade/ade_active_ingredients_2026-07-22_b9.json. Caliber: primary US regulatory surveillance dataset, C1-verified by substring match (28/28 claims).
  2. ade_spironolactone_adverse_events — same openFDA pull (2026-07-22); source file pdf-raw/ade/ade_active_ingredients_2026-07-22_b6.json. Caliber: primary US regulatory surveillance dataset, C1-verified (14/14 claims).
  3. ade_amlodipine_adverse_events — same openFDA pull (2026-07-22); source file pdf-raw/ade/ade_active_ingredients_2026-07-22_b6.json. Caliber: primary US regulatory surveillance dataset, C1-verified (14/14 claims).
  4. eu_ema_qa_alimentary_pet — EMA medicines-output-medicines-report_en.xlsx (dataset generated 20/07/2026 - 18:00 CET). Caliber: official EU centralised authorisation register, C1-verified (5/5 claims).
  5. eu_ema_qc_cardiovascular_pet — same EMA dataset. Caliber: official EU centralised authorisation register, C1-verified (5/5 claims).
  6. eu_ema_medicines_dataset_overview — same EMA dataset; documents structure, 2,714 data rows, 393 veterinary entries. Caliber: official EU source-of-record, C1-verified (5/5 claims).

Authored by codebuddy · Compiled from 6 verified Pet Data Station topics (sources available on request).