Four-week sub-acute toxicity study of S-(-)-9-fluoro-2,3-dihydro-3-methyl-10- (4-methyl-1-piperazinyl)-7-oxo-7H-pyrido-[1,2,3,-de] [1,4]benzoxazine-6- carboxylic acid hemihydrate (DR-3355) in CD rats and cynomolgus monkeys

Relation between statistics and treatment-related changes obtained from toxicity studies in rats: if detected a significant difference in low or middle dose for quantitative values, this change is considered as incidental change?

The purpose of a toxicity test is to determine the no-observed-effect level (NOEL) of test substance through biological and pharmacological techniques. If the low dose not does show statistically significant and biologically relevant changes in the data evaluated in a study, the usual practice is to consider this dose as the NOEL. To overcome this, 6 types of techniques that seemed to be appropriate are presented in this paper by investigating the results of several domestic and foreign theses on toxicology. The most appropriate techniques appear to be the trend test, comparison between treatment group and historical control by t-test, and confirmation that all individual values lie within the 95% confidence interval (2 SD) of the historical control value, if a significant difference is admitted in the low dose.

Post-Marketing Surveillance of the Safety of Levofloxacin in Japan

BACKGROUND

Central nervous system reactions to new quinolones, such as convulsions due to interaction with nonsteroidal anti-inflammatory drugs (NSAIDS), have attracted increased attention in Japan.

METHODS

The safety of levofloxacin (LVX) was investigated in Japan by post-marketing surveillance and reviewing spontaneous reports.

RESULTS

Post-marketing surveillance was performed in 16,117 patients between 1994 and 1996. The incidence of adverse reactions was 1.3% (203/16,117), being comparable with that for ofloxacin or that shown by phase II/III studies. Among 4,977 patients receiving concomitant NSAID treatment, the overall incidence of adverse reactions and the incidence of neurological reactions (including convulsions) did not significantly differ from those in patients without anti-inflammatory therapy. Review of the spontaneous reports on convulsions showed that patients with nephropathy, patients over 75 years and patients with a history of convulsive diseases were more likely to develop convulsions during LVX therapy.

CONCLUSION

LVX should be used cautiously in patients with the above risk factors.