Osteoarthritis pain in dogs: grapiprant vs placebo — POSSIBLE

In dogs with osteoarthritis pain, does daily grapiprant improve pain and function scores vs placebo?

Shelf #183 · gate-verified and displayed under the developer's blinded-trial rule

POSSIBLE: In the single randomised, masked, placebo-controlled trial of grapiprant for canine osteoarthritis pain (285 dogs enrolled, 262 evaluable), daily grapiprant 2 mg/kg produced more owner-assessed treatment success at day 28 than placebo — 48.1% vs 31.3%, an absolute difference of about 17 percentage points (P = .0315) — with pain scores and veterinary assessments also significantly favouring grapiprant, and occasional vomiting the commonest cost (17.02% vs 6.25%) (Rausch-Derra 2016). One pivotal registration trial with a modest margin and a not-overwhelming P value is moderate evidence: enough to say grapiprant probably helps some dogs, not enough to rank it against other analgesics — that comparison is a different shelf. This is a single-trial shelf, stated on its face. Drafted Nov 10, 2026 (VetMed build, topic #183); all figures from abstracts fetched and verified at drafting.

Rausch-Derra 2016: day-28 CBPI treatment success 48.1% on grapiprant vs 31.3% on placebo (262 evaluable dogs)

Prospective, randomised, masked, placebo-controlled multisite study

Who: Dogs: 285 client-owned dogs with osteoarthritis enrolled and treated with daily oral grapiprant (2 mg/kg) or placebo, with 262 cases (131 in each group) evaluable for the effectiveness analysis, in a prospective, randomised, masked, placebo-controlled multisite study. Owners completed the Canine Brief Pain Inventory (CBPI) on days 0, 7, 14, 21 and 28; veterinary assessments were made at screening and on days 14 and 28. Grapiprant is an EP4 prostaglandin receptor antagonist.

Result: Treatment success at day 28 was 48.1% on grapiprant vs 31.3% on placebo (P = .0315) — an absolute difference of about 17 percentage points. Pain interference score (P = .0029) and pain severity score (P = .0022) also improved more in the grapiprant group, and veterinary assessments were significantly better in grapiprant-treated dogs (P = .0086). Grapiprant was generally well tolerated, but a higher percentage of treated dogs (17.02%) had occasional vomiting than in the placebo group (6.25%).

Watch out: This is the only placebo-controlled trial of grapiprant for canine osteoarthritis pain found for this shelf, and it is the product's pivotal registration study. 'Masked' is the record's own word for its blinding. The success gap is modest and the primary P value (.0315) leaves less margin than the bedinvetmab trials on shelf #181.

Rausch-Derra L, Huebner M, Wofford J et al. A Prospective, Randomized, Masked, Placebo-Controlled Multisite Clinical Study of Grapiprant, an EP4 Prostaglandin Receptor Antagonist (PRA), in Dogs with Osteoarthritis. J Vet Intern Med. 2016;30(3):756-763. PMID: 27075237. Registry ID: none in the record. MeSH: Animals · Dog Diseases · Dogs · Osteoarthritis · Pain · Receptors, Prostaglandin E, EP4 Subtype · Sulfonylurea Compounds · Vomiting · Imidazoles · Pyridines · Benzenesulfonamides

Synthesis: one good pivotal trial — grapiprant beats placebo on pain scores, modestly, with vomiting the main cost

Synthesis

Who: Synthesis of the card above: Rausch-Derra 2016 (randomised, masked, placebo-controlled, multisite; 262 evaluable dogs) — the only placebo-controlled trial of grapiprant in canine osteoarthritis found for this shelf.

Result: Owner assessments, the CBPI component scores, and independent veterinary assessments all point the same way in the one trial: about 17 more dogs in 100 achieve treatment success on grapiprant than on placebo at 28 days, at the price of occasional vomiting in about 17% of treated dogs (vs 6.25% on placebo). As a non-COX-inhibiting EP4 antagonist, grapiprant is often chosen where a conventional NSAID is a concern — but no placebo-controlled trial carded here compares it head-to-head with an NSAID, so this shelf makes no comparative claim.

Watch out: Single-trial shelf by the charter's VetMed exception, stamped POSSIBLE: the trial is large and masked, but it stands alone, its primary result is modest (P = .0315), and it was run as the product's registration study.

Synthesis of Rausch-Derra L et al. PMID: 27075237. Registry ID as on the individual card.

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