Therapeutic activity of vidarabine in symptomatic chronic active hepatitis related to HBV

The potential inhibitory effects of nucleoside analogues such as ARA-A and acyclovir on HBV-DNA-polymerase were first demonstrated in vitro and then confirmed in vivo in open dose finding studies. The therapeutic efficacy of both ARA-A and ARA-AMP which appeared the most potent drugs was then confirmed by various studies in symptomatic HBeAg-positive patients. These studies demonstrated a similar benefit of therapy with 38 and 40% of treated patients given ARA-A and ARA-AMP, respectively, who permanently cleared HBV replication after a single course, and 67-80% who did so after two courses. Significant improvement in transaminases and histologic activity was also documented (P less than 0.001). Myalgias were observed in 10 and 30% of the patients, respectively. Patients who failed to respond to nucleosides, and those coinfected with HDV, were treated with interferons. Out of 8 cases of HDV/CAH given 5 MU thrice weekly of fibroblast beta-interferon (UPSA) for 3 months, DNA-p activity fell transiently in all 6 initially elevated cases. A parallel decrease in anti-HD titers (P less than or equal to 0.05), inflammation (P less than or equal to 0.001) and necrosis (P less than or equal to 0.05) were observed. alpha-Recombinant interferon was given i.m. for 4 months (2-7 MU/m2 X 2/7 days) to 10 CAH with high DNA-p values. HBV replication was permanently inhibited in 4 cases and dramatically reduced in 3 additional patients. Three failed to respond. Careful monitoring of DNA-p values appeared to be the single most important factor in assessing activity.

Pharmacokinetics of isoxicam in hepatic disease

1 The pharmacokinetics of single and repeated oral doses of isoxicam, an extensively metabolized drug, were studied in patients with compensated and decompensated hepatic disease. 2 After a single oral dose, isoxicam was slowly absorbed and eliminated (half-life ranging from 10.5 to 53.9 h). Its pharmacokinetics did not differ from those observed in healthy volunteers and were not significantly influenced by the severity of hepatic disease. However, the t1/2 of isoxicam was found to be inversely (r = -0.700, P less than 0.05 n = 14) related to the log gamma-glutamyl transpeptidase plasma activity. 3 During chronic oral treatment in patients with compensated hepatic insufficiency, steady-state was achieved after 7-9 days of therapy. The mean elimination half-life of isoxicam in five patients was 42.6 +/- 4.5 h, a value which was not statistically different from that obtained in the single dose study. 4 It was concluded that patients with hepatic insufficiency do not require a systematic modification of drug dosage but that long-term treatment should be employed with caution in these patients.