Biapenem is semi-synthetic amphoteric carbapenem antibiotic synthesised and commercially developed in the late 1990s by Japanese researchers at Lederle (now Pfizer). Biapenem possesses a broad antibacterial spectrum of action including anaerobes and is stable to most β-lactamases. Biapenem is more stable against hydrolysis by human renal dehydropeptidase-I (DHP-I) than other penems, such as meropenem, imipenem and panipenem. The improved dehydropeptidase activity is attributed to the presence of the 1-β-methyl moiety.