Description
Biapenem was introduced in Japan as a parenteral treatment for bacterial
infections. This new 1-β-methylcarbapenem can be prepared by reaction of commercially
available 4-nitrobenzyl protected β-methylcarbapenem enolphosphate with mercapto
bicyclotriazolium chloride, obtained in 11 steps starting from hydrazine, followed by
deprotection of the carboxylic acid function. Biapenem is a bacterial cell wall synthesis
inhibitor with a broad spectrum in vitro antibacterial activity encompassing many Gramnegative
and Gram-positive aerobic and anaerobic bacteria, including species producing
β-lactamases. Like imipenem, biapenem is moderately active against fnferococcus
faecalis and E. faecuirn and is inactive against methicillin-resistant Staphylococcus aureus.
Biapenem is stable to hydrolysis by human renal dihydropeptidase I (DHP-I) and therefore
does not require the coadministration of a DHP-I inhibitor. In clinical trials, biapenem
showed good clinical and microbiological efficacy in the treatment of patients with intraabdominal,
lower respiratory tract and complicated urinary tract infections. After
intravenous administration, the drug is widely distributed, has linear pharmacokinetics and
is mainly excreted in the urine with an elimination half-life of approximately 1 h. Biapenem
is generally well tolerated, the most common adverse events being skin eruptions/rashes,
nausea and diarrhea.
Chemical Properties
Off-White Solid
Definition
ChEBI:Biapenem is a carbapenem antibiotic in which the azetidine and pyrroline rings carry 1-hydroxymethyl and pyrazolo[1,2-a][1,2,4]triazolium-6-ylthio substituents respectively. It has a role as an antibacterial drug. It is a member of carbapenems, a pyrazolotriazole and an organic sulfide.
Antimicrobial activity
A semisynthetic carbapenem with a 2-substituted triazolium
moiety. It has broad-spectrum activity against most aerobic
and anaerobic Gram-positive and Gram-negative organisms.
It is equivalent to, or slightly more active than, imipenem
against Gram-negative aerobic bacteria and slightly less active
than imipenem against Gram-positive organisms. It is stable
to hydrolysis by dehydropeptidase. It is not hydrolyzed by
most serine β-lactamases, but like all carbapenems and penems
is readily hydrolyzed by carbapenemases. It penetrates
into bronchial epithelial lining fluid with peak concentrations
of 2.4–4.4 mg/L. The plasma half-life is 1.5–1.9 h. The potential
for neurotoxicity is less than that of imipenem.
Biochem/physiol Actions
Biapenem is a broad spectrum, carbapenem-based antibiotic with activity against both Gram-positive and Gram-negative bacterial strains.
Clinical Use
Biapenem is a newer second-generation carbapenem withchemical and microbiological properties similar to those ofmeropenem. Thus, it has broad-spectrum antibacterial activitythat includes most aerobic Gram-negative and Grampositivebacteria and anaerobes. Biapenem is stable toDHP-I67 and resistant to most β-lactamases. It is claimedto be less susceptible to metallo-β-lactamases than eitherimipenem or meropenem. It is not active orally.
