CLINICAL STUDIES - GENERIC MEDICINES
ANTONIO J. ALVES
LTQF - Bioequivalence Center, Pharmaceutical Sciences Department, UFPE, Cidade Universitária, Recife, PE, Brazil.
Presented by HELIO B. COUTINHO
Clinical testing is not the only way to discover drug effects on people. That is the reason controlled clinical trials are the only legal basis for central regulatory agencies in each country, such as FDA, to conclude that a new drug has clinical effectiveness for a drug or biologic. Before clinical testing begins, researchers analyze the drug's main physical and chemical properties in the laboratory and study its pharmacological and toxic effects in laboratory animals. On the other hand, bioequivalence studies are the clinical test used, most often, when a sponsor proposes manufacture a generic version of an approved off-patent product. The law 9.787 (1999), established the legal basis for the institution of generic drugs in Brazil. Our research group started clinical trial and bioequivalence studies, with collaboration of the Public Pharmaceutical Laboratory of Pernambuco State (LAFEPE), the Brazilian official company to pioneer the development of medicines for AIDS and herperviruses treatment, between 1995 to 1998, even before the establishment of generic policy in Brazil. In 1997 and 1998, LAFEPE was ranked in 21st market position vs. all public and private pharmaceutical laboratories in Brazil. The Aids medicines at a low cost increased the production and sales, and were the main reason of such inedited result.
As a result of the studies developed, the following medicines were introduced to the Brazilian market by LAFEPE: stavudine and zidovudine (AZT) capsules, ganciclovir injectable, lamivudine + AZT, didanosine, lamivudine, and zalcitabine tablets. The result showed bioequivalence for lamivudine tablets (RT) as the 90% CI for both Cmax (99,7) and AUC0-12 (96,7) geom. mean ratios lie within the 80-125% interval. On AZT + DDI therapy the plasma HIV RNA levels decreased > 0, 5 log after 30 days. The ganciclovir clinical study showed similar results in reference product by the control of retinitis in Aids patients infected with CMV. The stavudine and zalcitabine clinical study demonstrated no adverse effects reported and biochemical parameters remained unchanged and within the reference range. The pharmacokinetics parameters found for AZT + Lamivudine tablet were: AUC0-12 (8975 e 12.189ng.h/ml); Cmax (7.330 e 3.610 ng/ml) respectively, similar to the reference medicine. (May 24, 2002).
* E-mail: leac@nlink.com.br
Publication Dates
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Publication in this collection
09 Oct 2002 -
Date of issue
Sept 2002
