Merck has announced it will stop manufacturing and marketing Recarbrio (imipenem-cilastatin/relebactam) in the United States, citing a routine portfolio review rather than any safety or quality concerns. Approved by the FDA in 2019 for complicated urinary tract and intra-abdominal infections — and later expanded to hospital-acquired pneumonia and pediatric use — Recarbrio was designed to combat multidrug-resistant Gram-negative bacteria, including carbapenem-resistant Enterobacterales (CRE).

Infectious disease experts are divided on the clinical impact. While alternatives like ceftazidime-avibactam and cefiderocol exist for KPC-producing CRE, the loss will be most acutely felt in treating difficult-to-treat Pseudomonas aeruginosa, where options are limited. The bigger concern, however, is what this signals for the antibiotic market overall — because stewardship programs limit new antibiotic use to only the most resistant cases, these drugs generate little revenue, making them commercially unsustainable.

Key Takeaways:

• The clinical gap is described as "immediate but narrow," with the greatest impact on Pseudomonas aeruginosa treatment options
• Merck had completed rare pediatric post-approval studies, expanding Recarbrio's label to children as small as 2 kg — a milestone few smaller companies achieve
• The PASTEUR Act, which would provide fixed federal payments for novel antibiotics, has bipartisan support but has yet to pass Congress since its 2020 introduction

Why it matters: Recarbrio's withdrawal underscores a systemic market failure in antibiotic development. If even large pharma companies can't sustain these drugs commercially, the pipeline for future antibiotics — especially for children — is at serious risk.