Efficacy and tolerability of imipenem-cilastatin versus ceftazidime plus tobramycin as empiric therapy of presumed bacterial infection in neutropenic cancer patients.

The efficacy and tolerability of monotherapy with imipenem-cilastatin (I-C) were compared with that of ceftazidime plus full-course therapy with an aminoglycoside (tobramycin) (C&T) in the treatment of presumed bacterial infection in neutropenic cancer patients. A total of 106 adult patients diagnosed with presumed bacterial infection and an underlying malignancy with an absolute neutrophil count (ANC) < 500/mm3 were enrolled in this open-label study. A total of 131 febrile episodes occurred. Forty-five patients in the I-C group and 41 in the C&T group, who were well matched on demographic and baseline characteristics, were evaluable for efficacy and safety. Seventy-two hours after the start of therapy, no significant between-group differences in treatment outcomes, including withdrawals or deaths, were seen. Thirty-five (78%) of 45 patients in the I-C group and 29 (71%) of the 41 in the C&T group had successful outcomes at the final evaluation. Superinfection occurred in 8 (18%) I-C patients and 3 (7%) C&T patients. Within the subgroup of patients with an initial ANC < 100/mm3, the final evaluation showed no significant differences in treatment outcome between groups. Of the 131 in the safety population 30 (46%) I-C patients and 28 (42%) C&T patients had one or more adverse experiences; drug-related adverse events occurred in 25 (38%) patients in the I-C group and 11 (17%) patients in the C&T group. The data suggest that imipenem-cilastatin should be considered for initial empiric therapy of presumed bacterial infection in neutropenic cancer patients.