Retrospective Analysis of the Use of Tiludronate in Equine Practice: Safety on 1804 Horses, Efficacy on 343 Horses.

The objective of this retrospective study was to assess the safety and efficacy of a slow IV administration of 1mg/kg tiludronate in a large number of horses. Each horse that received at least one tiludronate-based treatment between 2006 and August 2019 at Virginia Equine Imaging or Fairfield Equine was included in the study. Concomitant medical treatments, preliminary nonsteroidal anti-inflammatory drug injection and potential side effects were recorded after each administration. Horses for which follow-up was available over 1 year were subject to clinical evolution assessment via lameness grade evolution and performance data when available. Collected data suggest excellent tolerance to tiludronate with only 0.9% of the 2,497 injections (1,804 horses) inducing potential side effects, mild colics being the most frequent. Clinical follow-up was available over more than 1 year for 343 horses. Most horses (>80%) presented an initial lameness score over 1.5/5, approximately half of the population was sound by 30 days and remained so after a year. Mean lameness score improved by more than one grade during the follow-up period compared to initial examination. Performance data were available for 129 horses. One year after treatment, 89 (69%) horses were still competing, 73 (82%) of them at a better or similar level. These data suggest good efficacy of tiludronate over a year after treatment. Despite limitations inherent to any field study, this is the first retrospective study of the use of bisphosphonates in horses combining a large group with long-term follow-ups.