The antibiotic ertapenem has been approved for treatment of adults with
moderate to severe forms of the following:
- complicated intra-abdominal infections;
- complicated skin/skin structure infections;
- community-acquired pneumonia (CAP);
- complicated urinary tract infections, including pyelonephritis; and
- acute pelvic infections, including postpartum endomyometritis, septic
abortion, and postsurgical gynecologic infections.
Each indication is limited to infections caused by designated microorganisms;
these include numerous common gram-positive and gram-negative aerobic and
anaerobic bacteria.
Ertapenem is a 1-(beta) methyl-carbapenem that is structurally related
to beta-lactam antibiotics.
Efficacy. Approval was based on one or two comparative clinical
trials for each indication. Ertapenem was compared with parenteral piperacillin/
tazobactam for intra-abdominal infections (N = 665), skin and skin structure
infections (N = 540), and acute pelvic infections (N = 412), and with parenteral
ceftriaxone for CAP (N = 866) and urinary tract infections (N = 850). In
all studies, ertapenem yielded microbiologic and/or clinical success rates
that were highly comparable with those for the comparator antibiotic.
Safety. Among the 1,954 patients treated with ertapenem in clinical
trials, the most common drug-related adverse events were diarrhea (5.5%
incidence), infused-vein complications (3.7%), and nausea (2.2%). Most adverse
events were described as mild to moderate.
Labeling warns of a risk of seizures and other central nervous system
(CNS) adverse events. In clinical trials, seizures occurred in 0.5% of ertapenem
recipients during therapy or a 14-day follow-up period. Seizures occurred
most often in patients with CNS disorders or renal impairment.
Because lidocaine HCl is used as a diluent, intramuscular administration
of ertapenem is contraindicated in patients with hypersensitivity to amide-type
local anesthetics.
Dosing. Ertapenem is supplied in single-dose vials. The recommended
dosage is 1 g given once daily by 30-minute intravenous infusion (for up
to 14 days) or by intramuscular injection (for up to 7 days). Recommended
treatment durations range from 3 to 14 days, depending on the infection.
The dosage should be reduced to 500 mg once daily in patients with advanced
or end-stage renal insufficiency; no adjustment is needed for other degrees
of renal impairment. If a patient receives the 500-mg dose within 6 hours
before hemodialysis, a supplemental dose of 150 mg is recommended after
the hemodialysis session.
Pricing was unknown at press time.
