Pneumocandins have concentration-dependent antifungal activity and higher dose of caspofungin (HD-CAP) in combination with other licensed antifungal therapy (OLAT) may improve response. Thirty-four patients who received HD-CAP were compared with 63 patients who received standard dose (SD)-CAP. There were no differences between the groups in either patient or disease characteristics. Significantly more patients in the HD-CAP arm had extrapulmonary infections (29 vs 8% in SD group; P=0.0053), and non-Aspergillus species infection (21 vs 6%; P=0.05) and had received prior antifungal therapy (71 vs 33%; P=0.0004). No serious adverse reactions were noted in patients receiving HD- or SD-CAP therapy. Twelve weeks after treatment commenced 44% had a complete or partial response compared with 29% in SD-CAP group (P=0.1). Logistic regression analysis showed a significant probability of a favorable outcome at 12 weeks in patients who received HD-CAP (OR 3.066, 95% CI, 1.092-8.61; P=0.033). This may in part reflect higher number of patients in HD group had received granulocyte-macrophage colony-stimulating factor (41 vs 14% in SD group; P=0.04) and/or interferon gamma (26 vs 5% in SD group; P=0.003) immune enhancement. Further studies are needed to evaluate efficacy of HD-CAP in severely immunosuppressed cancer patients with invasive fungal infections.