August 28, 2025

Today the U.S. Food and Drug Administration approved Gamrozyne (gamithromycin) injectable solution for the treatment of bovine respiratory disease (BRD) associated with Mannheimia haemolytica, Pasteurella multocida, Histophilus somni and Mycoplasma bovis in beef and non-lactating dairy cattle. Gamrozyne is also indicated for the control of respiratory disease in beef and non-lactating dairy cattle at high risk of developing BRD associated with Mannheimia haemolytica and Pasteurella multocida. Gamrozyne is the first FDA-approved generic version of Zactran (gamithromycin) injectable solution.

The FDA determined that product is bioequivalent to the pioneer product, Zactran (NADA 141-328) and residues in edible tissues from cattle treated with Gamrozyne will not represent a public health concern when the product is used according to the label, including a withdrawal period of 35 days. 

Gamrozyne is administered to beef and non-lactating dairy cattle through a subcutaneous injection in the neck at rate of 6 mg/kg (2 mL/110 lb) body weight. If the total dose exceeds 10 mL, divide the dose so that no more than 10 mL is administered at each injection site. 

Gamrozyne is only available by prescription from a licensed veterinarian because professional expertise is required to accurately diagnose BRD and monitor the safe and effective use of this product. 

The application is sponsored by Bimedia Animal Health Ltd. based in Ireland. 

Source from FDA:https://www.fda.gov/animal-veterinary/cvm-updates/fda-approves-first-generic-gamithromycin-injectable-treatment-and-control-bovine-respiratory-disease

veterinary syringe