Background: Moxifloxacin (Izilox) is prescribed for bacterial respiratory tract infections. ECG analysis done in clinical trials showed a mean QT prolongation at 6 ms that could lead to Torsades de Pointe. However, Izilox was well tolerated during clinical trials. To confirm the correct safety profile of Izilox in a large sample of patients, a French PMS study - MMEDIAT - was carried out in usual medical practice.
Methods: This prospective observational uncontrolled and monitored study was conducted in 13,578 patients with respiratory tract infection and treated with moxifloxacin 400 mg daily (duration: 5 to 10 days in accordance to the Market Authorization). Any clinical event being potentially a surrogate of a ventricular rhythm disorder ("critical event") were collected and analyzed by a Scientific Committee in charge to determine the potential cardiac origin of the reported event and to establish a causal relationship with the treatment.
Results: Among 13,578 patients, 1046 adverse events (678 patients [5%]) were reported, including 854 drug related events (564 patients [4.15%]). Of these 1046 adverse events, 95 (62 patients [0.46%]) were serious. A total of 189 critical adverse events (159 patients [1.2%]) were reviewed by the Scientific Committee. After analysis, 34 adverse events (28 patients [0.21%]) were assessed from potential cardiac origin. Of these 34 adverse events, 25 (19 patients [0.14%]) were assessed as drug-related: palpitations [13 patients], tachycardia [4 patients], malaise [4 patients], vertigo [3 patients] and pallor [1 patient]. All adverse events were transient and had favourable outcome.
Conclusion: This PMS study confirmed that Izilox is well-tolerated in usual medical practice, in adequation with the safety data obtained in clinical trials.