Meropenem-vaborbactam as a combination has demonstrated enhanced in vitro activity against gram-negative organisms, particularly Enterobacterales with class A and C carbapenemases.

KPC is the most dominant strain of carbapenemase-resistant Enterobacterales (CRE). Meropenem-vaborbactam has been shown in multiple in vitro studies of globally sourced isolates to be a potent inhibitor of Enterobacterales with KPC enzymes.

Meropenem-vaborbactam does not have activity against OXA-48 or metallo-beta lactamases, thus was least effective in strains from the Asia-Pacific region where MLBs are prevalent and was most effective against strains from the US.

Compared to currently available antibiotics, meropenem-vaborbactam demonstrated lower MIC values against both clinical and engineered isolates, including engineered E. coli strains that had KPC, SHV, and TEM enzymes.

Sub-analysis in the TANGOII trial demonstrated meropenem-vaborbactam had a lower potential for resistance to develop.