Expiry Date For Drug Products

[Sunjay]

Dear All,

I would like to have ur view on following:

An API has expiry date of 2 years (Mfg in March 2005).

we uses this API in December 2006 in the tablets. Based on stability studies on tablets we give expiry date of 2 years to the tablets i.e. upto Dec 2008.

So in this case our API is expired longback in March 2007, but the tablets will be still available?

Does this mean that in stability study for tablets we are mainly determining the compatibility of the API and excipients.

Pls share your views.

Thanks

[Alex Buske]

Sunjay,

Usually specifications are different for API (often 97-103%) and Drug product (often 95-105%). The API expiry is the latest date Drug products can be produced. After that date the API is not allowed for production.
The expiry date of the drug product is determined in extra stability studies. It would be good practise to use at least one batch that was made of API close to the expiry date.

Alex

[jitender]

Agree to Alex.
Just before the manufacture of drug product, your drug substance need to be re-tested and it should be within specification for manufacture of drug product.

[bkirschil]

Once you formulate with your API and it is now in the formulated matrix the extablished shelf life3 or expiration date of the product supercedes the prior retest date of the API prior to formulation.