Cefdinir versus cephalexin for the treatment of skin and skin-structure infections. The Cefdinir Adult Skin Infection Study Group.

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.