Background: Ciprofloxacin is a broad-spectrum fluoroquinolone antibiotic used in the treatment of a wide range of mild to moderate gram-positive and gram-negative infections. Although extensive information is available on the safety profile of ciprofloxacin in adults, few published data exist regarding the tolerability and toxicity of this drug in patients aged greater than or equal to 65 years. Objectives: The objectives of this retrospective analysis were to compare the safety profile of ciprofloxacin in patients aged greater than or equal to 65 years versus patients aged <65 years and to compare the adverse-event profile of ciprofloxacin with that of other comparator antimicrobial agents used in clinical trials. Methods: We retrospectively reviewed 23 prospective, controlled anti-infective clinical trials in the US Payer ciprofloxacin database that included patients aged <greater than or equal to>65 years. These trials comprised the submission file of the original and supplemental New Drug Application for ciprofloxacin. The incidence of treatment-emergent and drug-related adverse events was assessed. Results: Of the 6863 patients in these 23 clinical trials, 3579 received ciprofloxacin therapy and 3284 received comparator antimicrobial agents. Of the ciprofloxacin-treated patients, 898 (25.1%) were aged greater than or equal to 65 years; 887 (27.0%) of the patients who received comparator antimicrobial agents were aged greater than or equal to 65 years. Among ciprofloxacin-treated patients, drug-related adverse events were reported more often in those aged <65 years (24.0%) compared with those aged <greater than or equal to>65 years (17.9%). The incidence of drug-related adverse events in the comparator group was also higher in those aged <65 years (25.1%) than in those aged <greater than or equal to>65 years (16.8%). Premature discontinuation due to any adverse event was reported in 3.9% (105 of 2681) and 3.7% (33 of 898) of ciprofloxacin-treated patients aged <65 years and <greater than or equal to>65 years, respectively. Corresponding rates for the comparator antimicrobial group were 3.9% (93 of 2397) and 3.8% (34 of 887), respectively, for patients aged <65 years and <greater than or equal to>65 years. The most common drug-related adverse events reported for ciprofloxacin-treated patients aged <65 years and <greater than or equal to>65 years were digestive system-related (18.1% and 11.4%, respectively) and central nervous system-related events (6.6% and 4.9%, respectively). Conclusions: This retrospective analysis suggests that there is no clinically important difference in the safety profile of ciprofloxacin in patients aged greater than or equal to 65 years versus patients aged <65 years.
