Clinical reactivation during lamivudine treatment correlates with mutations in the precore/core promoter and polymerase regions of hepatitis B virus in patients with anti-hepatitis B e-positive chronic hepatitis.

BACKGROUND: Drug-resistant mutants may emerge in patients with chronic hepatitis B receiving lamivudine therapy. AIM: To evaluate whether different viral mutational patterns may be associated with clinical reactivation during lamivudine treatment in patients with chronic B hepatitis. METHODS: Eight anti-hepatitis B e-positive patients with (group A) and 14 patients without clinical exacerbation (five anti-hepatitis B e-positive, group B1; nine hepatitis B e antigen-positive, group B2) during lamivudine treatment were investigated. RESULTS: 'Polymerase region': M204V/I variants were found in all group A patients, but in none of group B1 (P=0.0007) and in four of nine of group B2 (44%; P=0.02) patients. The L180M substitution was detected in four of eight (50%) of group A and in none of groups B1 and B2. 'Core promoter': the double basic core promoter (A1762T/G1764A) variant was detected in seven of eight (87%) of group A and in one of five (20%; P=0.03) of group B1 and one of nine (11%; P=0.002) of group B2 patients. 'Precore': the G1896A stop codon mutation was present in seven of eight (87%) of group A and in zero of five (P=0.004) of group B1 and one of nine (11%; P=0.002) of group B2. CONCLUSIONS: Different mutational patterns were observed in the lamivudine-treated patients with and without exacerbation. There was an association of the basic core promoter and stop codon mutations with lamivudine resistance in patients with disease exacerbation.

Are the 2-isomers of the drug rimantadine active anti-influenza A agents?

There is a lack of information in the medical chemistry literature concerning the anti-influenza A activity of the drug rimantadine's 2-isomer (2-rimantadine). We now present results showing that, although 2-adamantanamine (2-amantadine) 3 is only moderately active, some 2-rimantadine analogues are effective anti-influenza A virus agents in vitro. The 2-rimantadine analogues and their spirocyclobutane and spirocyclopentane congeners were synthesized through interesting routes. The 2-rimantadine analogues were 2-4 times more potent than rimantadine 2 against influenza virus A H2N2 strain; their spirocyclobutane congeners proved equally active to rimantadine 2. Two compounds exhibited a similar activity and one of the compounds was was fourfold more potent than rimantadine 2 against H3N2 strain.