Original article Ertapenem monotherapy versus combination therapy with ceftriaxone plus metronidazole for treatment of complicated intra-abdominal infections in adults Albert E. Yellin a , James M. Hassett b , Alvaro Fernandez c , James Geib d , Ben Adeyi d , Gail L. Woods d, *, Hedy Teppler d , The 004 Intra-abdominal Infection Study Group a LAC-USC Medical Center, Los Angeles, CA, USA b Millard Fillmore Hospital, Buffalo, NY, USA c Hospital Roosevelt, Guatemala, Guatemala d Merck Research Laboratories, West Point, PA, USA Received 28 February 2002; accepted 10 May 2002 Abstract The efficacy and safety of intravenous (IV) ertapenem, 1 and 1.5 g once a day, for treatment of adults with complicated intra- abdominal infection were compared with those of IV ceftriaxone 2 g once a day plus IV metronidazole 500 mg every 8 h. After at least 3 days of IV therapy and satisfactory clinical response, patients could be switched to oral ciprofloxacin plus metronidazole. Fifty-nine patients were randomized to receive ertapenem 1 g and 51 to receive ertapenem 1.5 g; 55 patients were randomized to each comparator group. At the test of cure, 4 /6 weeks post therapy, in the 1 g cohort, 84% (26/31) of patients treated with ertapenem and 85% (35/41) with comparator therapy had a favourable clinical and microbiological assessment. Success rates in the 1.5 g cohort were 83% (22/29) and 77% (24/31) in the ertapenem and comparator groups, respectively. Drug-related adverse events were generally similar in both treatment groups. Ertapenem 1 or 1.5 g once a day followed by optional oral therapy appeared similar to combined therapy with ceftriaxone plus metronidazole with the same optional oral switch for treatment of complicated intra-abdominal infections in adults. Although not compared directly in a randomized fashion, the efficacy and safety profiles of ertapenem 1 and 1.5 g appeared comparable. Ertapenem was generally well tolerated and had an overall safety profile similar to ceftriaxone plus metronidazole. # 2002 Elsevier Science B.V. and International Society of Chemotherapy. All rights reserved. Keywords: Ertapenem; Intra-abdominal infection; Clinical trial 1. Introduction Complicated intra-abdominal infections are among the most common infectious problems faced by the general surgeon. Effective management requires early diagnosis, timely and appropriate surgical intervention and adequate antimicrobial therapy. Since culture results generally are not available for the first 48  /72 h following surgery, empirical antimicrobial therapy must cover the most likely pathogens, i.e. a mixture of Gram- positive and Gram-negative aerobic and anaerobic bacteria that comprise the usual flora of the gastro- intestinal tract. Escherichia coli and Bacteroides fragilis are the two most common isolates in most studies of intra-abdominal infections [1  /5]. In 1992, the Surgical Infection Society (SIS) published treatment guidelines concerning anti-infective agents for intra-abdominal infection based on data from in vitro susceptibility testing, animal models, and clinical trials [6]. Since most such infections are polymicrobial, the regimens recommended by SIS and others that have been used successfully have efficacy against facultative Gram- negative enteric bacilli and anaerobes [7  /10]. Ertapenem (formerly MK-0826, Merck & Co., Inc.) is a recently licensed once a day parenteral b-lactam antimicrobial agent that can be utilized as monotherapy * Corresponding author. Present address: Merck & Co., Inc., 10 Sentry Parkway, BL3-4, Blue Bell, PA 19422, USA. Tel.:  /1-484-344- 2481; fax:  /1-484-344-3404 E-mail address: gail_woods@merck.com (G.L. Woods). International Journal of Antimicrobial Agents 20 (2002) 165  /173 www.isochem.org 0924-8579/02/$ - see front matter # 2002 Elsevier Science B.V. and International Society of Chemotherapy. All rights reserved. PII:S0924-8579(02)00160-7