Vaborbaktam

Vaborbaktam is a boron-containing beta-lactamase inhibitor used in combination with the carbapenem antibiotic meropenem to treat certain resistant bacterial infections. It is marketed in combination as meropenem/vaborbaktam under the brand name Vabomere.

Mechanism and spectrum: Vaborbaktam inhibits serine beta-lactamases, notably class A enzymes such as KPC and some class C enzymes, thereby protecting meropenem from hydrolysis and restoring its activity against many beta-lactamase-producing Enterobacterales and related pathogens. It has limited activity against metallo-beta-lactamases (class B) and generally does not inhibit certain OXA-type enzymes (class D). As a result, the combination is most useful against organisms that rely on serine beta-lactamases for carbapenem resistance, with reduced activity against metallo-beta-lactamase producers.

Clinical use: Meropenem/vaborbaktam is indicated for adults with complicated urinary tract infections, including acute pyelonephritis, and has been approved for hospital-acquired bacterial pneumonia and ventilator-associated pneumonia in later labeling. The regimen typically consists of 4 g total dose (2 g meropenem and 2 g vaborbaktam) every 8 hours, given as an infusion over about 3 hours; renal function guides dosing adjustments.

Safety and resistance: Common adverse effects resemble those of other beta-lactams and may include nausea, headache, diarrhea, and infusion-site reactions; there is a risk of Clostridioides difficile infection. Seizures or encephalopathy may occur at high doses or in patients with CNS disorders. Resistance can arise through mechanisms such as loss of porins or emergence of non-inhibited beta-lactamases, and the combination is not effective against bacteria producing metallo-beta-lactamases or certain OXA-type enzymes.

Pharmacokinetics: Both components are primarily eliminated renally, necessitating dose adjustments for impaired kidney function.