This is an executive summary summary of photo stability testing of drug substance and drug product of ICH guidelines (Quality)

1. FAKEHA NAEEM
MPHIL
PHARMACEUTICS
STABILITY TESING:
PHOTOSTABILITY
TESTING OF NEW DRUG
SUBSTANCES AND
PRODUCT
Q1B
(EXECUTIVE SUMMARY)

2. TOPIC COVERED:
 1. GENERAL
 A. PREAMBLE
 B. LIGHT SOURCES
 C. PROCEDURES
 2. DRUG SUBSTANCE
 A PRESENTATION OF SAMPLE
 B.ANALYSIS OF SAMPLE
 C.JUDGEMENT OF RESULTS
 3. DRUG PRODUCT
 A.PRESENTATION OF SAMPLE
 B.ANALYSIS OF SAMPLE
 C. JUDMEMNT OF RESULTS

3. LIGHT SOURCES
OPTION 1
 D65/ID65
D65:
Internationally recognized
standard for outdoor day light as
defined in ISO 10977(1993)
ID65:
is equivalent indoor indirect day light
standard.
OPTION 2
 A cool florescent lamp: ISO
10977(1993)
 A near UV fluorescent lamp: 320 nm to
400 nm And maximum energy
emission between 350 nm and 370 nm

4. PROCEDURES: CONFIRMATORY STUDIES
 Sample should be exposed to light providing an overall illumination of not less than 1.2
milion lux hours and integrated near ultraviolet energy of not less than 200 watt
hours/square meter
 Samples may be exposed side by side with validated chemical actinometric system to
ensure the specified exposure is obtained
 If protected samples(wrapped in aluminum foil ) are
used as dark control to evaluate
the contribution of thermally induced
change to the total observed change

6. PHOTOSTABILITY TESTING ON DRUG
SUBSTANCES:
1. FORCED DEGREDATION TESTING:
 Evaluates the photosensitivity drug used alone or in solution/suspension
 Placed in chemically inert & transparent containers.
 Variety of exposure condition(depends on photosensitivity & intensity )
2.CONFIRMATORY TESTING:
 Provides Information necessary for handling, packaging and labeling
 Gives idea of precautionary measures
needed in manufacturing or in formulation development

7. PHOTOSTABILITY TESTING ON DRUG
SUBSTANCES:
PURPOSE OF FOCED DEGREDATION TESTING:
The purpose of forced degradation testing studies to evaluate the overall
photosensitivity of the material for:
o method development purposes
 degradation pathway elucidation.

8. PHOTOSTABILITY TESTING ON DRUG
SUBSTANCES:
PURPOSE FOR CONFIRMATORY STUDIES:
Purpose of confirmatory studies are:
 To provide the information necessary for handling, packaging, and labeling
 only one batch of drug substance is tested during the development phase ,if the
drug is clearly photo stable or photolabile,then photo stability characteristics is
confirmed.
 If the results of the confirmatory study are
equivocal, testing of up to two additional
batches should be conducted.

9. PHOTOSTABILITY TESTING ON DRUG
SUBSTANCE:
 A. PRESENTATION OF SAMPLE:
CONSIDRATION:
 Care should be taken to ensure the physical characteristics of the samples under test.
 the effects of the changes in physical states sublimation, evaporation or melting
interactions between the samples and container material. such as Appropriate amount of
samples should be taken in suitable glass or plastic dish, protected with suitable
transparent cover if necessary
 Solid drug substances : spread; thickness 3mm
 Liquid substances :container-chemically inert and
transparent containers.

10. PHOTOSTABILITY TESTING ON DRUG
SUBSTANCE:
B.ANALYSIS OF SAMPLE:
At the end of the exposure period, the samples should be examined for
1.Any changes in physical properties (e.g., appearance, clarity, or color of solution)
2. the assay
3. Any degradants ,likely to arise from photochemical degradation processes( by a method suitably
validated for products )
SAMPLING CONSIDRATION:-
o A representative portion of solid substances should be taken in individual tests.
o Homogenization of entire sample
o Analysis of exposed samples should be performed parallel With protected
sample used as dark control (if used in test).

11. PHOTOSTABILITY TESTING ON DRUG
SUBSTANCE:
C. JUDGEMENT OF RESULTS:
 The forced degradation studies provides suitable information to develop and
validate test methods for the confirmatory studies.
These test methods should be capable of:
 resolving and detecting photolytic degradants that appear during the confirmatory
studies.
 identification of precautionary measure
Confirmatory studies: to evaluate/determine whether change due to exposure to light
is acceptable

12. PHOTOSTABILITY TESTING ON DRUG
PRODUCT:
Studies on drug products
 The analytical procedures used should be suitably validated.
 done sequentially
 should progress until the results demonstrate that the drug product is adequately protected
from exposure to light.

13. PHOTOSTABILITY TESTING ON DRUG
PRODUCTS
PROCEDURE OF PHOTOSTABILITY TESTING OF DRUG PRODUCTS:
 The drug product is exposed to the light conditions
 only one batch of drug product is tested during the development phase
 if the product is clearly photos stable or photo labile then the photo stability characteristics
should be confirmed on a single batch
 If the results of the confirmatory study are equivocal, testing of up to two additional batches
should be conducted.
 For aluminum tubes or cans, testing conducted on directly exposed drug product.
 extent of this testing for infusion liquids, dermal creams, etc depend on the directions for
use

14. PHOTOSTABILITY TESTING ON DRUG
PRODUCT:
A. PRESENTATION OF SAMPLE:
Consideration of:
 the physical characteristics of the samples under test.
 the effects of the changes in physical states such as sublimation, evaporation or
melting
 interactions between the samples and
container material.

15. PHOTOSTABILITY TESTING ON DRUG
PRODUCT:
testing samples of the drug product outside of the primary pack:
 these should be presented in a way similar to the conditions mentioned for the drug substance.
 samples positioned to provide maximum exposure to the light e.g. tablets, capsules, etc., should
be spread in a single layer.
 If direct exposure not practical (e.g., due to oxidation of a product), the sample should be placed
in a suitable protective inert transparent container (e.g., quartz)
If testing of the drug product in the immediate container or as
marketed is needed:
 samples should be placed horizontally or transversely with respect to the light

16. PHOTOSTABILITY TESTING ON DRUG
PRODUCT:
B.ANALYSIS OF SAMPLE
At the end of the exposure period, the samples should be examined for
1 . Any changes in physical properties (e.g., appearance, clarity, or color of solution)
2. the assay
3. Any degradants ,likely to arise from photochemical degradation processes( by a
method suitably validated for products Sampling consideration

17. PHOTOSTABILITY TESTING ON DRUG
PRODUCT:
SAMPLING CONSIDRATION:
 A representative portion of solid substances should be taken in individual tests.
For solid oral dosage form products: appropriately sized composite of, e.g, 20 tablets or
capsules.
 Homogenization of entire sample (e.g., creams, ointments, suspensions, etc.).
 The analysis of the exposed sample should be performed parallel with that of any protected
samples used as dark controls if these are used in the test.

18. PHOTOSTABILITY TESTING ON DRUG
PRODUCT:
C. JUDGEMENT OF RESULT:
 special labeling or packaging requirement
 When evaluating the results of photo stability studies to determine whether
change due to exposure to light is acceptable, it is important to consider the
results obtained from other formal stability studies to assure that the product will
be within proposed specifications during the shelf life