"Canadian Generics" - Summary and Clinical Significance of Laboratory Analyses, 7/13/04

Drug	Ambien	Lipitor	Viagra
Identification	Pass (Drug Present)	Pass (Drug Present)	Pass (Drug Present)
Potency (Average of 20 tablets for each drug)	Fail 140% of Declared Potency	Fail 81% of Declared Potency	Fail 65% of Declared Potency
Dissolution (Single time point determination)	Pass 128% of Declared Label Amount The “pass” result is likely due to the super-potency.	Fail 55% of Declared Label Amount	Fail 67% of Declared Label Amount
Chromatographic Purity	Pass (No impurities detected)	Fail 5% Impurities	Fail 0.7% Impurities
Summary of Clinical Significance	All 20 sample tablets were more potent than the acceptable limit for the FDA-approved drug (up to 171% of approved potency). Sample tablets that are above the acceptable potency limit could put the patient at risk for central nervous system depression, leading to decreased mental alertness and loss of coordination (especially in an elderly or debilitated person).	There is a risk of clinical failure due to sub-potency. If a patient took the sub-potent sample product (perhaps having switched from the innovator to the sample product), an otherwise unsuspected reduction in efficacy (increase in cholesterol level) could result. While this may not present a problem in the short-term, the fact that the patient is not being treated optimally would put the patient at increased long-term risk for complications of high cholesterol, such as heart disease. The sample tablets may also be less safe due to the elevated impurities.	The sample tablets may be less clinically effective because of their reduced potency and poorer dissolution profile. The sample tablets may also be less safe due to the elevated impurities.
Comments	Several tablets were >140% potency, including one tablet that was almost double the potency of the FDA-approved drug (sample = 171%). This potency variability among the sample tablets (relative standard deviation = 11%) is usually indicative of a poor manufacturing process.	The potency variability among the sample tablets (relative standard deviation = 9%) is usually indicative of a poor manufacturing process.	The potency variability among the sample tablets (relative standard deviation = 11%) is usually indicative of a poor manufacturing process.

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