ImipenemRelebactam

Imipenemrelebactam is an intravenous fixed‑dose antibiotic combination of imipenem, cilastatin, and relebactam. Marketed under the brand name Recarbrio, it expands imipenem’s activity against beta-lactamase–producing bacteria by protecting it from enzymatic degradation.

Imipenem inhibits bacterial cell wall synthesis. Cilastatin blocks renal degradation of imipenem, increasing its systemic exposure. Relebactam inhibits class A and class C beta-lactamases, restoring and extending imipenem’s activity against many resistant Enterobacterales and Pseudomonas aeruginosa.

In adults, imipenemrelebactam is approved for complicated intra‑abdominal infections and complicated urinary tract infections, with an indication expansion to hospital‑acquired pneumonia and ventilator‑associated pneumonia. It is active against many Enterobacterales and Pseudomonas aeruginosa that produce beta‑lactamases, including some KPC producers, but it is not effective against organisms that produce metallo‑beta‑lactamases or certain other carbapenemases.

Pharmacokinetically, the combination is given by intravenous infusion and is primarily cleared by the kidneys, necessitating dose adjustments in renal impairment. Common adverse events include nausea, diarrhea, fever, headache, and vomiting. Serious hypersensitivity reactions and Clostridioides difficile infection have been reported, and caution is advised in patients with a history of beta‑lactam allergy.

Regulatory history: the product was developed by Merck. The FDA approved imipenemrelebactam in 2019 for cIAI and cUTI, with an expansion to HAP/VAP approved in 2020, broadening its use for serious gram‑negative infections caused by susceptible organisms.