[Code of Federal Regulations]
[Title 21, Volume 4]
[Revised as of April 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR211.166]

[Page 148-149]
 
                        TITLE 21--FOOD AND DRUGS
 
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN 
                          SERVICES (CONTINUED)
 
PART 211_CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS--
 
                      Subpart I_Laboratory Controls
 
Sec.  211.166  Stability testing.

    (a) There shall be a written testing program designed to assess the 
stability characteristics of drug products. The results of such 
stability testing shall be used in determining appropriate storage 
conditions and expiration dates. The written program shall be followed 
and shall include:
    (1) Sample size and test intervals based on statistical criteria for 
each attribute examined to assure valid estimates of stability;
    (2) Storage conditions for samples retained for testing;
    (3) Reliable, meaningful, and specific test methods;
    (4) Testing of the drug product in the same container-closure system 
as that in which the drug product is marketed;
    (5) Testing of drug products for reconstitution at the time of 
dispensing (as directed in the labeling) as well as after they are 
reconstituted.
    (b) An adequate number of batches of each drug product shall be 
tested to determine an appropriate expiration date and a record of such 
data shall be maintained. Accelerated studies, combined with basic 
stability information on the components, drug products, and container-
closure system, may be used

[[Page 149]]

to support tentative expiration dates provided full shelf life studies 
are not available and are being conducted. Where data from accelerated 
studies are used to project a tentative expiration date that is beyond a 
date supported by actual shelf life studies, there must be stability 
studies conducted, including drug product testing at appropriate 
intervals, until the tentative expiration date is verified or the 
appropriate expiration date determined.
    (c) For homeopathic drug products, the requirements of this section 
are as follows:
    (1) There shall be a written assessment of stability based at least 
on testing or examination of the drug product for compatibility of the 
ingredients, and based on marketing experience with the drug product to 
indicate that there is no degradation of the product for the normal or 
expected period of use.
    (2) Evaluation of stability shall be based on the same container-
closure system in which the drug product is being marketed.
    (d) Allergenic extracts that are labeled ``No U.S. Standard of 
Potency'' are exempt from the requirements of this section.

[43 FR 45077, Sept. 29, 1978, as amended at 46 FR 56412, Nov. 17, 1981]