Because of increasing resistance to older
antimicrobial agents, newer drugs need to be evaluated for the treatment of skin and skin-structure
infections (SSSIs). This double-masked, randomized, comparative, multicenter study enrolled patients aged 13 years or older with SSSIs to receive either
cefdinir 300 mg BID or
cephalexin 500 mg QID for 10 days. Nine hundred fifty-two patients (474 in the
cefdinir group and 478 in the
cephalexin group) took part, primarily white males between 18 and 65 years of age. There were two follow-up visits, with efficacy determined at the test-of-cure visit, 7 to 16 days posttherapy. Many patients were not microbiologically assessable, primarily because of negative cultures at study admission. Patients who required surgical intervention (e.g., incision and drainage) at the site of
infection more than 24 hours after the initiation of
drug therapy were defined as treatment failures. Significantly more isolated pathogens were resistant to
cephalexin than to
cefdinir. In the 178 efficacy-assessable
cefdinir-treated patients, the rate of pathogen eradication was 93% (200/215), and the rate of successful clinical response was 88% (157/178), compared with 89% (221/247) and 87% (177/204), respectively, in the 204 efficacy-assessable
cephalexin-treated patients. Using confidence-interval analysis, the microbiologic and clinical response rates of the
cefdinir-treated patients were statistically equivalent to those of the
cephalexin-treated patients. At the follow-up visits, patients were questioned about any adverse events occurring since their previous visit. Any untoward symptom occurring during or within 2 days after completion of
drug treatment was considered an adverse reaction if the investigator judged it to be definitely, probably, or possibly related to the study
drug. One hundred twenty-three (26%)
cefdinir-treated patients and 77 (16%)
cephalexin-treated patients experienced at least one adverse reaction, a statistically significant difference. Study
drug was discontinued for adverse reactions in 20 (4%)
cefdinir-treated patients and 13 (3%)
cephalexin-treated patients; in the two groups, 10 and 7 patients, respectively, were discontinued for
diarrhea.
Cefdinir taken BID was as effective as
cephalexin taken QID in the treatment of mild-to-moderate SSSIs and was well tolerated by most patients. The increased antibacterial activity of
cefdinir must be balanced against the higher rate of
diarrhea seen in patients treated with this
drug.