Oral omeprazole is the accepted treatment for equine squamous gastric disease (ESGD). However, it is not universally effective. Esomeprazole results in more consistent and pronounced acid suppression in people and is more effective than omeprazole in the treatment of oesophageal and gastric disease. Pharmacodynamic and pilot clinical studies have indicated esomeprazole might also be more effective than omeprazole in horses.
The aim of the randomized, single-blinded controlled trial was to compare the efficacy and safety of oral esomeprazole and omeprazole pastes in the treatment of ESGD and, where present, concurrent equine glandular gastric disease (EGGD).
Horses presenting with grade ≥2 ESGD lesions were randomly allocated to receive 4 mg/kg of either a buffered esomeprazole or omeprazole paste orally once daily for 28 days before gastroscopy being repeated within a further 3 days. Videos and images were anonymized and subsequently graded blind by one researcher. The severity of ESGD (and EGGD) lesions before and after treatment, and thereby treatment responses, were compared using univariable logistic regression.
Horses were mostly in either low-level or no work, with a mix of breeds represented. A higher proportion of horses had ESGD healing in response to esomeprazole treatment (63/74, 85%) than with omeprazole treatment (43/73, 59%) (odds ratio [OR]: 4.00, 95% confidence interval [CI]: 1.81, 8.82, p = 0.001). In a subset of horses that had concurrent EGGD, a greater proportion of the horses treated with esomeprazole had lesions ≤ grade 1 (esomeprazole 28/51, 55%; omeprazole 6/24, 25%; OR: 3.65, 95% CI: 1.25, 10.71, p = 0.02) Using grade 0 as the benchmark for EGGD healing, the difference remained significant (OR: 4.44, 95% CI: 1.33, 14.85, p = 0.02).
Oral-buffered esomeprazole was a more effective treatment for ESGD (and concurrent EGGD) than oral-buffered omeprazole in this population of horses.