Formestane Inquiry Widens Across Victoria

Another six Victorian training operations have been drawn into racing's prolonged formestane investigation after Racing Victoria issued presentation charges relating to horses tested between April and November last year. Matthew Brown, Adam Chambers, Nathan Dunn, Lee and Shannon Hope, Lloyd Kennewell and Paul Preusker are the latest trainers required to answer allegations arising from detections of formestane and the associated compounds 4-hydroxytestosterone and 6a-hydroxyandrostenedione. The affected horses are Rip 'N' Rip, Major Share, Inthelapofthegods, Iluvcoffee, Nursery Chime and Chairman. Each trainer has been charged under Australian Rule of Racing 240(2), which applies when a horse is presented to race with a prohibited substance in its system irrespective of how the substance came to be present. The latest cases take the number of Victorian stables involved in formestane positives to 13, with the detections occurring between February 2023 and November 2025. The unusual cluster has created considerable uncertainty because Racing Analytical Services Limited had screened for the relevant compounds from 2017 without identifying a single positive during the first six years. Twenty-four samples have subsequently contained the substances across thoroughbred and harness racing in Victoria, South Australia and Tasmania, as well as racing in Chile, despite the laboratory maintaining that its equipment, methodology and sensitivity have not changed. Formestane is an aromatase inhibitor previously used in the treatment of breast cancer, while 4-hydroxytestosterone and 6a-hydroxyandrostenedione are classified as anabolic androgenic steroids. Racing rules require a horse returning an anabolic steroid positive to be prohibited from racing for 12 months, meaning all six horses were automatically stood down from the dates on which their samples were taken. Racing Victoria has commissioned an international research project to investigate whether very low concentrations of the substances may occur naturally and whether future thresholds or treatment provisions should be considered. However, any later alteration to the regulatory position is considered unlikely to apply retrospectively, leaving the current cases to be determined under the rules operating when the samples were collected. Six earlier matters have already been finalised before the Victorian Racing Tribunal, with the trainers pleading guilty to presentation charges and receiving fines, decisions that now provide a penalty reference for those still outstanding. Brown, Chambers, Kennewell and Preusker are expected to have their cases heard by Racing Victoria stewards because their positives occurred after the presentation rule was removed from the Serious Offence List in July 2025. The Dunn and Hope matters predate that change and have consequently been referred to the tribunal. Racing Victoria said no Victorian thoroughbred detections had been recorded since November 2025 and that no additional investigations were presently underway, but the broader scientific question surrounding the cluster remains unresolved.