1995 Volume 43 Issue 11 Pages 1048-1061
Vancomycin hydrochloride (VCM) for injection has been marketed since November 1991 as an indication severe for infections caused by methicillin-resistant Staphylococcus aureus (MRSA). The overall results of post-marketing surveillance for the past three years are shown below.The subjects were 1, 354 patients to whem the drug was intravenously administered in a study period from December 1991 to October 1994 in 650 facilities, and a total of 1, 255 cases were chosen among them as the subjects for evaluation of efficacy excluding 99 cases which the physicians in charge had classified as unable to judge. Daily doses of the drug were 40 mg/kg for children, and 1 g or 2 g for adults for a period of 1-3 weeks. In addition, decrease in daily dose as well as shortening of the administration period were observed with time. When observed improvement rates according to diseases, the improvement rate was 78. 7% for pneumonia, and 87.5% for sepsis, exhibiting an improvement rate of 81.7% as a whole. On the other hand, the improvement rates were higher for the patients who had not been given a previous drug, but, no difference was observed in the improvement rates among daily doses or in patients with or without concomitant drugs. The antibacterial effect was 64.2% for pneumonia, and 88.5% for sepsis, 69.8% bacterial eradication rate as a whole. There were 271 episodes of subjective or objective adverse reactions and abnormal laboratory findings in 191 patients (14.1%). Especially for the abnormal laboratory findings on renal function, the incidence in the adult and elderly patients was higher for the patients daily dose of 2 g than that for those with 1 g daily. The plasma level monitoring was performed in 1, 082 cases in 500 patients out of 1, 354 patients (36.9%)(2.2 cases per 1 patient). The rates of monitoring practice were showing an increasing trend in accordance with progress of year. Pharmacokinetics analysis revealed decrease in creatinine clearance (Ccr) in many cases of the elderly patients. A linear relationship was observed among elimination constant (e), VCM clearance, and Ccr. A β-phase elimination half-life (t1/2 β) was extended, accompanying with decrease in Ccr, and even for the cases withmild decrease in renalfunction the elimination half-life was prolonged to nearly three times the value of healthy adults. The above results thus obtained prove that the VCM injection is a highly useful drug showing the sufficient effects for MRSA infection and is thereby considered best to immediately administer to the cases in which phlogogenous bacteria is identified as MRSA. Adverse reaction can be minimized when in use, if appropriate use and dose are applied by performing the plasma level monitoring along with consideration of ages and renal function.
