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, Recarbrio was designed to combat multidrug-resistant Gram-negative bacteria — including carbapenem-resistant Enterobacterales (CRE) — and was most recently expanded for pediatric use in 2025.

Infectious disease experts say the clinical gap is "immediate but narrow," as alternatives like ceftazidime-avibactam and meropenem-vaborbactam remain available for most indications. However, the loss is most acutely felt for difficult-to-treat Pseudomonas aeruginosa infections, where Recarbrio was one of a limited number of preferred options.

The bigger concern, many say, is what this signals for the antibiotic market overall. Because stewardship programs rightly limit antibiotic use to patients who truly need them, new drugs generate little revenue — making them financially unsustainable for manufacturers.

Key Takeaways:

• The PASTEUR Act, which would provide fixed federal payments for novel antibiotics, has bipartisan support but has not yet passed
• Small-to-midsize pharma companies completed only 10% of required pediatric post-approval studies, per a 2025 study
• Merck had fulfilled its pediatric postmarketing requirement, expanding Recarbrio's label to children as small as 2 kg — a rare achievement

Why it matters: Recarbrio's withdrawal is a warning sign for the antibiotic pipeline. Without sustainable business models, drugmakers may abandon the space entirely, leaving patients — especially children — with fewer options against life-threatening drug-resistant infections.