Drugmaker Merck announced that it will no longer manufacture or market the antibacterial combination drug Recarbrio in the United States.
A combination of the antibiotic imipenem-cilastatin and the beta-lactamase inhibitor relebactam, Recarbrio was approved by the U.S. Food and Drug Administration (FDA) in 2019 to treat adults with complicated urinary tract infections and intra-abdominal infections and without alternative treatment options. It was approved for adults with hospital-acquired and ventilator-associated bacterial pneumonia in 2020 and expanded for use in children in 2025.
Recarbrio was developed to target multidrug-resistant infections, particularly pathogens with resistance mechanisms that can disable beta-lactam antibiotics, such as Klebsiella pneumoniae carbapenemase (KPC), present in carbapenem-resistant Enterobacteriaceae (CRE) infections. It is one of several combinations of beta-lactams and beta-lactamase inhibitors that have been developed in recent years to address the growing threat of drug-resistant bacteria and was initially touted by the company as an important new tool for patients suffering from difficult-to-treat infections.
“At a time of great public health concern about the need for new treatments to address the evolving challenges posed by Gram-negative bacteria, we are proud to continue to bring new therapeutic options to healthcare practitioners in an effort to help them overcome the challenges of patient care,” said Nicholas Kartsonis, MD, senior vice president of clinical research, infectious diseases and vaccines at Merck Research Laboratories, in a 2020 release. press release.
The company said the decision to remove the drug from the U.S. market was part of an ongoing review of its portfolio and was not related to any safety or quality issues with the product.
An “immediate but narrow” clinical gap
“We understand that Recarbrio has been an important option for some patients. Alternative treatment options remain available for approved indications; patients should consult their physician to determine the appropriate course of action,” a Merck spokesperson told CIDRAP News.
Amesh Adalja, MD, an infectious disease physician and senior scholar at the Johns Hopkins University Center for Health Security, said the clinical void left by stopping Recarbrio is “immediate but narrow.”
“For KPC-producing CREs, the resistance that relebactam was designed to overcome, we still have drugs like ceftazidime-avibactam, meropenem-vaborbactam and cefiderocol. The loss will be felt most in hard-to-treat cases. Pseudomonas aeruginosa, where imipenem-relebactam was on a short list of preferred options,” Adalja said.
But Brad Spellberg, MD, chief medical officer at Los Angeles General Medical Center, said he wasn’t surprised, given that the drug is “not in any way meaningfully differentiated from the multiple other drugs on the market.” Spellberg was skeptical of Recarbrio even before it was approved.
“This drug was never going to be used,” Spellberg said.
Concerns about market failure
For others, the move raises more questions about the viability of the market for new antibiotics. Because the patient population with multidrug-resistant infections and no alternative treatment options is limited and antibiotic stewardship programs are needed in U.S. hospitals, most new antibiotics are rarely used.
“We rightly reserve new antibiotics for patients who actually need them, but that means these drugs will sit on shelves for long periods of time and generate little revenue,” said Henry Skinner, PhD, CEO of the AMR Action Fund.
We rightly reserve new antibiotics for patients who actually need them, but that means these drugs will sit on shelves for long periods of time and generate little revenue.
Skinner said he was particularly concerned about the implications for pediatric patients with multidrug-resistant infections. Citing a 2025 study published in the journal Antibioticshe noted that the small and mid-sized pharmaceutical companies currently driving antibiotic development have completed only 10% of the required pediatric post-approval studies, which are needed to expand drug labels for pediatric use, and that none have received pediatric approval for their products.
“Merck has done the lengthy and expensive work required to meet pediatric post-marketing requirements and expand Recarbrio’s label to children weighing as little as 2 kilograms,” Skinner said. “If big companies can’t keep these products on the market, who will generate the evidence needed to bring future antibiotics to children?
Skinner and Adalja said they believe a solution could be provided by the PASTEUR law, a bill that establish a new payment model for new antibiotics, under which companies would receive fixed annual payments from the federal government for new antibiotics.
“Until this becomes policy, more releases like this will happen, which means fewer new antibiotics,” Adalja said.
Although the legislation has received bipartisan support since it was first introduced in Congress in 2020, it has not yet passed into law.
Gn Health
