Recently, clinical data has emerged suggesting that the fluoroquinolone, gatifloxacin, can affect glucose homeostosis through an unknown mechanism. In order to explore the potential effects of moxifloxacin on glucose metabolism in humans, a pooled analysis of phase II/III clinical trials and postmarketing studies was performed and compared with results from an investigation in laboratory animals.
A pooled analysis of 30 (26 controlled, 4 uncontrolled) oral and two intravenous/oral prospective, controlled phase II/III moxifloxacin studies was performed to evaluate the frequency of hyper- and hypoglycaemic episodes and glucose-related adverse events and adverse reactions (i.e. those considered to be drug related) versus comparator antimicrobials (penicillins, cephalosporins, macrolides, doxycycline, fluoroquinolones). Similar evaluations were conducted on data pooled from five postmarketing surveillance studies. In addition, potential effects of supratherapeutic doses of moxifloxacin on blood glucose and plasma insulin levels in fed and fasted rats were assessed in comparison with those of gatifloxacin, levofloxacin and glibenclamide (glyburide).
The phase II/III database was comprised of 14,731 patients (8474 moxifloxacin, 6257 comparator antimicrobial). There were no drug-related hypoglycaemic adverse events reported for moxifloxacin in either the oral or intravenous/oral database. Two drug-related hypoglycaemic adverse events were reported in the oral comparator group, both following administration of levofloxacin and both of mild severity; one drug-related hypoglycaemic adverse event was reported in the intravenous/oral comparator group after trovafloxacin administration. Drug-related hyperglycaemic adverse events were reported in seven (<0.1%) moxifloxacin and 1 (<0.1%) comparator-treated patients in the oral study database, none of these cases were considered serious and six of the seven moxifloxacin cases were graded as mild and required no countermeasures. There were no cases of drug-related hyperglycaemic events in any patient enrolled in the intravenous/oral studies. Coadministration of oral antidiabetic drugs with moxifloxacin or comparator antimicrobials did not change the rate of blood glucose increases or decreases in diabetic patients. Data from five moxifloxacin postmarketing studies (46 130 subjects) reported no episodes of hypoglycaemia and two non-drug-related hyperglycaemic episodes. Data from animal studies revealed that supratherapeutic doses of moxifloxacin and levofloxacin did not affect blood glucose or plasma insulin levels in both fed and fasted rats, whereas gatifloxacin decreased both blood glucose and plasma insulin in a dose-dependent manner in fed rats only. The reference compound glibenclamide increased insulin and decreased glucose levels as expected.
Hyperglycaemic or hypoglycaemic adverse reactions were reported rarely in studies with oral or sequential intravenous/oral moxifloxacin, and incidence was comparable in moxifloxacin and comparator groups. Changes in glucose metabolism were also similar in diabetic patients treated with moxifloxacin compared with those patients without diabetes mellitus. This comprehensive analysis of the datapool for moxifloxacin phase II/III clinical trials and postmarketing studies suggests that moxifloxacin administration has no clinically relevant effect on blood glucose homeostasis.