Bioequivalence study of a single 150-mg dose of two intramuscular netilmicin products in Thai healthy volunteers.

ABSTRACT

Objective: Netilmicin, a broad-spectrum semisynthetic aminoglycoside antibiotic, is used in the treatment of a wide variety of bacterial infections. The purpose of this study is to compare the bioavailability of two products of 150 mg netilmicin by intramuscular administration in Thai healthy volunteers The generic drug is Nelin® (test; Biolab Co., Ltd., Thailand) will be called “Test” and Netromycin® (reference; Schering-Plough Ltd., USA) will be called “Reference”. Methods: A single-dose, 2-treatment, 2-period, 2-sequence, randomized crossover study was conducted in 24 healthy Thai volunteers. Each volunteer received a 150 mg intramuscular injection of the reference or test drugs. Blood samples were collected before dosing and at various time points up to 48 hours after dosing and analyzed for netilmicin concentrations using a validated liquid chromatography-mass spectrometry (LC-MS/MS) method. The pharmacokinetic parameters including Cmax, AUC0-t, AUC0-¥, Tmax and t1/2 were analyzed using the non-compartmental model. Drug safety and tolerability were assessed. Results: Twenty-four volunteers completed both treatment periods. The geometric mean ratios (test/reference) between the two products of netilmicin were 100.30% (90% CI, 88.02%-114.28%) for Cmax, 94.94% (90% CI, 88.94%-101.34%) for AUC0-t, and 94.88% (90% CI, 88.85%-101.32%) for AUC0-¥. There was no significant difference of the Tmax values between the two studied products (P>0.05). No adverse events related to the study drugs were found. Conclusion: The two products of intramuscular netilmicin are bioequivalent. Both products are well tolerated.