Oral sugar test responses to ertugliflozin in ten horses with insulin dysregulation

BackgroundPreliminary evidence indicates that ertugliflozin benefits horses and ponies (hereafter collectively referred to as horses) with hyperinsulinaemia and hyperinsulinaemia-associated laminitis. The effects of ertugliflozin on the results of the oral sugar test used widely in the assessment of insulin dysregulation (ID), have not been reported.ObjectivesTo report the effects of ertugliflozin on responses to the oral sugar test (OST) in horses with ID.Study designRetrospective case series.MethodsClinical records were reviewed to identify horses with ID that had an OST (0.45 mL/kg Karo-Light PO) performed before and after 4 days of treatment with 0.05 mg/kg ertugliflozin PO s.i.d. Pre- and post-treatment insulin concentrations were compared using Wilcoxon sign-ranked tests.ResultsTen horses with ID met the inclusion criteria. Significant reductions in plasma insulin concentration were identified at all time points after 4 days of treatment with ertugliflozin relative to pre-treatment values. At T0 (prior to oral sugar), median insulin concentration reduced from 22.4 mu u/mL (IQR: 6.5, 39) pre-treatment to 4.8 mu u/mL (IQR: 3.7, 9.2) at day 4 (p = 0.004). At T60 (60 min after oral sugar), median insulin concentration was 165 mu u/mL (IQR: 61.2, 222) pre-treatment and 78.1 mu u/mL (IQR: 30.5, 137) at day 4 (p = 0.004). At T90 (90 min after oral sugar), median insulin concentration was 170 mu u/mL (IQR: 88.6, 269) pre-treatment and 84.7 mu u/mL (IQR: 28.7, 122) at day 4 (p = 0.002). Serum triglyceride concentration increased from a median of 0.4 mmol/L (IQR: 0.2, 0.8) pre-treatment to 0.9 mmol/L (IQR: 0.6, 2) at day 4 of ertugliflozin treatment (p = 0.006).Main limitationsA small heterogenous group of horses and ponies, some with PPID, were used in the absence of a control group.ConclusionsFour daily doses of ertugliflozin at 0.05 mg/kg was associated with lowering of insulin concentrations at baseline and in response to an OST in horses with ID; however, insulin levels did not return to normal in all horses. Increases in triglyceride concentrations were also observed.