title: Bioavailability study of two oral formulations of didanosine in healthy volunteers.
abstract: An open-label, randomised, crossover single dose study, using 2 periods, 2 sequences, with a minimum washout period of 7 days, was conducted in order to assess the comparative bioavailability of two formulations of didanosine (CAS 69655-05-6) 100 mg tablets. Didanosine plasma concentrations were determined by means of a validated HPLC method [DAD detector, stavudine (CAS 3056-17-5) as an internal standard]. The limit of detection was 30 ng/ml. The results showed that overall classical 90 % confidence intervals (CI) were 92.4-111.2 % for AUC0-inf, 91.8-109.9 %f for AUC0-t, and 87.0-110.0 % for Cmax. Since the 90 % CI for both, AUC and Cmax ratios were within the 80-125 % interval proposed by the European Agency for the Evalution of Medicinal Products (EMEA) and Food and Drug Administration (FDA), it is concluded that the new didanosine formulation is equivalent to the conventional formulation for both, the extent and the rate of absorption after single dose administration in healthy volunteers.
authors.affiliation: Departamento de Farmácia, Faculdade de Ciências Farmacêuticas de São Paulo, Brazil.
authors.forename: Simone
authors.initials: S
authors.lastname: Schramm Andrade
authors.forename: Eunice Kazue
authors.initials: EK
authors.lastname: Kano
authors.forename: Tatiane Maria
authors.initials: TM
authors.lastname: de Lima Souza Brioschi
authors.forename: Eunice Emiko Mori
authors.initials: EE
authors.lastname: Koono
authors.forename: Cristina Helena
authors.initials: CH
authors.lastname: dos Reis Serra
authors.forename: Valentina
authors.initials: V
authors.lastname: Porta
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001682:Biological Availability; D002138:Calibration; D002626:Chemistry, Pharmaceutical; D016049:Didanosine / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D007202:Indicators and Reagents; D008297:Male; D011786:Quality Control; D012015:Reference Standards
chemical_list: D019380:Anti-HIV Agents; D007202:Indicators and Reagents; D016049:Didanosine