Antibiotics in acute exacerbations of chronic bronchitis

Early investigational antibiotics for the treatment of acute exacerbations of chronic bronchitis

INTRODUCTION

Acute exacerbations in patients with chronic bronchitis are a leading cause of hospitalizations and death. Bacteria contribute significantly to such exacerbations. The aim of this review was to explore the potential role of investigational antibiotics in the treatment of these episodes. Areas covered: The available literature in PubMed database, in websites related to investigational drugs and in websites of the producing companies has been searched. The in vitro activity against pathogens involved in acute exacerbations of chronic bronchitis and the pharmacokinetic profile of antibiotics currently under development were taken into consideration for inclusion in the review. Expert opinion: Several novel antimicrobial agents have completed preclinical and Phase I studies and were well-tolerated. Further investigation is mandatory in order to evaluate their future in treatment of chronic bronchitis exacerbations and discover potential advantages compared to already approved antimicrobials.

Moxifloxacin versus amoxicillin/clavulanic acid in outpatient acute exacerbations of COPD: MAESTRAL results

Bacterial infections causing acute exacerbations of chronic obstructive pulmonary disease (AECOPD) frequently require antibacterial treatment. More evidence is needed to guide antibiotic choice.

The Moxifloxacin in Acute Exacerbations of Chronic Bronchitis TriaL (MAESTRAL) was a multiregional, randomised, double-blind non-inferiority outpatient study. Patients were aged ≥60 yrs, with an Anthonisen type I exacerbation, a forced expiratory volume in 1 s <60% predicted and two or more exacerbations in the last year. Following stratification by steroid use patients received moxifloxacin 400 mg p.o. q.d. (5 days) or amoxicillin/clavulanic acid 875/125 mg p.o. b.i.d. (7 days). The primary end-point was clinical failure 8 weeks post-therapy in the per protocol population.

Moxifloxacin was noninferior to amoxicillin/clavulanic acid at the primary end-point (111 (20.6%) out of 538, versus 114 (22.0%) out of 518, respectively; 95% CI -5.89–3.83%). In patients with confirmed bacterial AECOPD, moxifloxacin led to significantly lower clinical failure rates than amoxicillin/clavulanic acid (in the intent-to-treat with pathogens, 62 (19.0%) out of 327 versus 85 (25.4%) out of 335, respectively; p=0.016). Confirmed bacterial eradication at end of therapy was associated with higher clinical cure rates at 8 weeks post-therapy overall (p=0.0014) and for moxifloxacin (p=0.003). Patients treated with oral corticosteroids had more severe disease and higher failure rates.

The MAESTRAL study showed that moxifloxacin was as effective as amoxicillin/clavulanic acid in the treatment of outpatients with AECOPD. Both therapies were well tolerated.

A novel study design for antibiotic trials in acute exacerbations of COPD: MAESTRAL methodology

Antibiotics, along with oral corticosteroids, are standard treatments for acute exacerbations of chronic obstructive pulmonary disease (AECOPD). The ultimate aims of treatment are to minimize the impact of the current exacerbation, and by ensuring complete resolution, reduce the risk of relapse. In the absence of superiority studies of antibiotics in AECOPD, evidence of the relative efficacy of different drugs is lacking, and so it is difficult for physicians to select the most effective antibiotic. This paper describes the protocol and rationale for MAESTRAL (moxifloxacin in AECBs [acute exacerbation of chronic bronchitis] trial; www.clinicaltrials.gov: NCT00656747), one of the first antibiotic comparator trials designed to show superiority of one antibiotic over another in AECOPD. It is a prospective, multinational, multicenter, randomized, double-blind controlled study of moxifloxacin (400 mg PO [ per os] once daily for 5 days) vs amoxicillin/clavulanic acid (875/125 mg PO twice daily for 7 days) in outpatients with COPD and chronic bronchitis suffering from an exacerbation. MAESTRAL uses an innovative primary endpoint of clinical failure: the requirement for additional or alternate treatment for the exacerbation at 8 weeks after the end of antibiotic therapy, powered for superiority. Patients enrolled are those at high-risk of treatment failure, and all are experiencing an Anthonisen type I exacerbation. Patients are stratified according to oral corticosteroid use to control their effect across antibiotic treatment arms. Secondary endpoints include quality of life, symptom assessments and health care resource use.