Imipenem/cilastatin therapy for serious infections in neonates and infants

Sixty-one hospitalized infants aged one day to six months were enrolled in an open, multicenter noncomparative clinical study of the efficacy and safety of imipenem/cilastatin. Patients weighing less than 1500 g (four males/ten females, Group 1) and those greater than or equal to 1500 g (31 males/16 females, Group 2) were analyzed separately. Total daily dose (divided into b.i.d. (27) or t.i.d. (34) regimens) ranged from 50 to 101.4 mg/kg given for 10.8 days (means, range 2 to 35 days) for Group 1 and 39.7 to 103 mg/kg given for 11.2 days (means, range 1 to 41 days) for Group 2. The investigators graded the intensity of signs and symptoms of infections as moderate or severe in 86 and 91% of patients in groups 1 and 2, respectively, and bacterial pathogens were isolated pretreatment in 43 and 32% of patients. Eighty-eight percent of all bacterial pathogens were susceptible to imipenem in vitro. The most commonly isolated pathogens were Pseudomonas aeruginosa and Klebsiella pneumoniae. Patients who had confirmed bacterial infections and who did not receive concomitant antibiotics were considered evaluable for efficacy, including 6 (43%) in Group 1 and 15 (32%) in Group 2. Infection sites were (Group 1) respiratory (100%), and (Group 2) skin and skin structures (33%), urinary (11%), gastrointestinal (11%), septicemia alone (11%) and meningitis or respiratory (28% and 6% with sepsis, respectively). Safety analysis included all patients. Imipenem/cilastatin was well tolerated in 93% of Group 1 and 85% of Group 2 patients. Three patients' treatments were discontinued due to rash, oliguria or poor local tolerability. Three patients in Group 1 and four in Group 2 died; deaths were considered unrelated to imipenem/cilastatin. Results are as follows: (table; see text) In summary, 81% (17 of 21) of evaluable patients were clinically cured or improved, among whom 3 of 21 patients (14%) had serious clinical or laboratory adverse experiences which were considered possibly related to imipenem/cilastatin. These results are comparable to results reported with other single or multiple antibiotic regimens.