In December 2008, the Center for Veterinary Medicine (CVM), part of the FDA, published the Guidance for Industry "Drug Stability Guidelines". This guideline is to be used as an aid for designing and conducting studies to establish drug stability in support of original animal drug applications (NADAs) or abbreviated new animal drug applications (ANADAs) or supplements. This data must be submitted to the FDA.
The guideline comprising 47 pages is valid for animal drugs as well as for medicated feed products.
Prior to submission for marketing authorisation, the applicant may submit his protocol for comment to the Center for Veterinary Medicine (CVM). The CVM may examine this protocol and comment on it but the stability protocol will not be approved by the CVM.
Concerning the strength/potency at the end of the expiration date period, this guideline states that 90% of the labelled potency is generally recognised as the minimum acceptable potency level.
It is recommended that the samples are stored at temperatures of 25oC and 37- 40oC, although in some instances, higher or lower temperatures may be required.
Stability samples from production-size batches are preferred and should be used for stability studies. To establish the initial data point, samples should be analysed as soon as possible after they are manufactured. The FDA desires that the analyses are carried out on the same day ("the same day is highly desirable")! According to the FDA, this is necessary in order to draw sound and valid conclusions about the stability of the active drug ingredient(s) and preparation thereof. If the initial analysis can not be performed on the same day, the samples should be stored in such a way that the change of quality is reduced as much as possible.
The maximum possible expiration date period for animal drugs is specified as five years. This period begins at the time of manufacture of the batch.
Furthermore, the FDA Guideline also refers to:
You can read the complete document here.
Dr Günter Brendelberger
On behalf of the European Compliance Academy (ECA)