Cystorelin®, Factrel®, Fertagyl®, Ovacyst®, AND NOW INTRODUCTING Gonabreed®, THE NEWEST GnRH ON THE BLOCK.
The use of Gonadotropin Releasing Hormone (GnRH) is a common, accepted, and promoted practice throughout the industry for use in synchronization programs. All the products available up to this date in the U.S. have been labeled only for treatment of ovarian cysts. So, use of any GnRH in a synchronization program has been an extra-label use of the drug.
Because no product had a label, we have often justified our position by the AMDUCA (Animal Medicinal Drug Use Clarification Act) algorithm that when there is not a labeled drug for a certain disease or process, we can use a drug extra-labelly that is effective. Some or all of you may remember estroPLAN®. Parnell, the producers of estroPLAN®, is re-entering the U.S. market and is in the process of launching GONAbreed® (Gonadorelin acetate), the first GnRH to have a label for use in the Ovsynch® protocol. They will be marketing GONAbreed® in a synchronization pack which includes 8-20mL vials of GONAbreed® and 8-20mL vials of estroPLAN® which will treat 80 cows. The total mLs of GnRH and PGF are the same because the GONAbreed® dose is 1mL instead of 2 like the other GnRHs. estroPLAN® is still a 2mL dose.
You may see or have already seen Parnell’s advertisements. Their argument is that AMDUCA is technically only applicable when the health of the animal is in danger, so use of reproductive hormones extra-labelly is technically still prohibited although it is a common and accepted practice. They hold the only labeled GnRH for use in synchronization programs and so all others will technically be prohibited. However, it is worth noting that use of a drug does not truly become illegal until a violative residue is identified.
It is unclear now what the full impact of this will be on the industry since the use of other GnRH products in synchronization programs will technically be prohibited, and we will have a legal, labeled product available. Because of the higher cost of GONAbreed® compared to other GnRHs and no difference in how the drug works or how effective it is, we as a clinic have decided to not carry it at this time. Keep your heads up and your ears open on this topic in the coming months. We will try our best to keep you up to date and informed. Let us know if you have any questions or concerns.