The safety and efficacy of caspofungin in the treatment of esophageal candidiasis was evaluated in one large, controlled, noninferiority, clinical trial and two smaller dose-response studies. 

In all 3 studies, patients were required to have symptoms and microbiological documentation of esophageal candidiasis; most patients had advanced AIDS (with CD4 counts <50/mm3). 

Of the 166 patients in the large study who had culture-confirmed esophageal candidiasis at baseline, 120 had Candida albicans and 2 had Candida tropicalis as the sole baseline pathogen whereas 44 had mixed baseline cultures containing C. albicans and one or more additional Candida species. 

In the large, randomized, double-blind study comparing caspofungin 50 mg/day versus intravenous fluconazole 200 mg/day for the treatment of esophageal candidiasis, patients were treated for an average of 9 days (range 7 to 21 days). Favorable overall response at 5 to 7 days following discontinuation of study therapy required both complete resolution of symptoms and significant endoscopic improvement. The definition of endoscopic response was based on severity of disease at baseline using a 4-grade scale and required at least a two-grade reduction from baseline endoscopic score or reduction to grade 0 for patients with a baseline score of 2 or less. 

The proportion of patients with a favorable overall response was comparable for caspofungin and fluconazole as shown in Table 12. 

The proportion of patients with a favorable symptom response was also comparable (90.1% and 89.4% for caspofungin and fluconazole, respectively). In addition, the proportion of patients with a favorable endoscopic response was comparable (85.2% and 86.2% for caspofungin and fluconazole, respectively). 

As shown in Table 13, the esophageal candidiasis relapse rates at the Day 14 post-treatment visit were similar for the two groups. At the Day 28 post-treatment visit, the group treated with caspofungin had a numerically higher incidence of relapse; however, the difference was not statistically significant. 

In this trial, which was designed to establish noninferiority of caspofungin to fluconazole for the treatment of esophageal candidiasis, 122 (70%) patients also had oropharyngeal candidiasis. A favorable response was defined as complete resolution of all symptoms of oropharyngeal disease and all visible oropharyngeal lesions. The proportion of patients with a favorable oropharyngeal response at the 5- to 7-day post-treatment visit was numerically lower for caspofungin; however, the difference was not statistically significant. Oropharyngeal candidiasis relapse rates at Day 14 and Day 28 post-treatment visits were statistically significantly higher for caspofungin than for fluconazole. The results are shown in Table 14. 

The results from the two smaller dose-ranging studies corroborate the efficacy of caspofungin for esophageal candidiasis that was demonstrated in the larger study. 

Caspofungin was associated with favorable outcomes in 7 of 10 esophageal C. albicans infections refractory to at least 200 mg of fluconazole given for 7 days, although the in vitro susceptibility of the infecting isolates to fluconazole was not known.