Fighting resistance with redundancy: a path forward for treating antimicrobial-resistant infections?

Carbapenem-resistant Acinetobacter baumannii (CRAB) remains a major threat, with high mortality and limited effective treatments. Sulbactam-durlobactam has emerged as a promising therapy against CRAB. Sulbactam-durlobactam was combined with imipenem-cilastatin in a clinical trial that led to its United States Food and Drug Administration approval. However, the additive benefit of imipenem remains uncertain. In a recent study (Antimicrob Agents Chemother 69:e01627-24, 2025, https://doi.org/10.1128/aac.01627-24), Veeraraghavan and colleagues provide convincing mechanistic evidence that adding imipenem to sulbactam-durlobactam enhances bacterial killing, likely through complementary inhibition of penicillin binding proteins, leveraging the concept of target redundancy.