FDA clears canine-labeled cosyntropin injection for adrenal testing

Veterinary professionals have a new FDA-approved option for ACTH stimulation testing in dogs: CosACTHen (cosyntropin injection) from Dechra. The product is the first cosyntropin injection specifically approved for canine patients for evaluating adrenal function, supporting diagnosis and monitoring in dogs with suspected hyperadrenocorticism or hypoadrenocorticism. FDA’s Freedom of Information summary shows the drug was approved on December 18, 2025, as a 0.25 mg/mL injectable solution supplied in 1 mL single-use vials, with a labeled dose of 0.25 mg per dog weighing 10 to 110 pounds, given IV or IM for ACTH stimulation testing. Dechra said the approval positions the product as a tool for confirming Addison disease, helping assess Cushing disease, and monitoring dogs receiving trilostane therapy. (animaldrugsatfda.fda.gov)

Why it matters: For clinicians, the approval gives a regulated, canine-labeled product in an area where ACTH stimulation testing has long been clinically important for adrenal workups and follow-up. FDA documents say effectiveness was supported by two laboratory studies and one multisite field study involving 119 dogs suspected of hypo- or hyperadrenocorticism, and the label includes both IV and IM administration. In the field study, adverse reactions were limited, with two dogs vomiting within eight hours and one developing a hematoma after IV administration; DailyMed also lists post-approval foreign-market reports including lethargy, GI signs, injection-site reactions, lameness, and hypersensitivity reactions. For practices managing dogs on trilostane, that matters because FDA notes that Cushing disease treatment often requires repeated blood tests and checkups in the first months and then periodic monitoring thereafter. (animaldrugsatfda.fda.gov)

What to watch: Watch for how quickly CosACTHen reaches clinic distribution, whether specialists and general practices adopt it as a preferred ACTH stim product, and whether its labeled canine indication changes testing workflows or client communication around adrenal disease monitoring. (biospace.com)