By Karen Blum
A novel triple-drug therapy known as Mino-Lok (MLT) was found to be highly effective and superior to standard of care antimicrobial locks in salvaging long-term central venous catheters for patients with cancer, those undergoing hemodialysis, or those who needed catheters for other conditions, according to a phase 3 international trial.
The study, conducted at 34 U.S. sites, including Puerto Rico, and India, demonstrated that a combination containing minocycline, edetate (disodium EDTA), and ethanol led to a notable difference in median time to catheter failure and enabled significantly more catheters to be retained compared with standard-of-care antimicrobial lock therapy, according to a poster presented at IDWeek 2025, in Atlanta (P101).
Central line catheters are a lifeline for patients with cancers or undergoing hemodialysis through which clinicians can deliver fluids or chemotherapy, yet infection is relatively common, with an attributable mortality of 12% to 25%, explained study co-author Issam Raad, MD, FACP, FIDSA, FSHEA, the G.H. Fletcher Endowed Distinguished Chair and University of Texas MD Anderson Cancer Center, in Houston.
“The simple thing is to remove them, and put another one in a different site,” Dr. Raad said, but added that may not be possible due to vascular access issues. Infectious Diseases Society of America guidelines recommend using antibiotics to sterilize the catheters from the inside, he said, “But all the best antibiotics cannot completely do that sterilization, and make the catheter stop being a source for the bloodstream infection.” Meanwhile, the FDA has not approved any adjunct antimicrobial lock therapy in combination with systemic antibiotics.
Mino-Lok combines antibiotics with a low concentration of ethanol and edetate calcium disodium to break the biofilm shell covering the bacteria inside the catheter. And it can be used immediately without waiting for culture results to determine the specific organism causing the infection to select the most appropriate antibiotic, said study co-author Anne-Marie Chaftari, MD, an associate professor of infectious diseases at MD Anderson. “It’s like a master key,” Dr. Raad added. “It works against all bacteria, no matter how resistant they are.”
From February 2018 to February 2024, investigators enrolled 241 patients ages 12 years and older with catheter-related or central-line associated bloodstream infections (CRBSI/CLABSI), each of whom had cancer, were undergoing hemodialysis, or for other reasons required a long-term central venous catheter. They were randomized 1:1 to receive either MLT or site-specific standard-of-care antimicrobial lock therapy for two hours per day for seven days. The primary end point was median time to catheter failure, defined as mortality; catheter removal due to inability to administer the lock or infection-related reasons; worsening signs or symptoms; persistent or recurrent bloodstream infection; or deep-seated infection.
A total of 228 patients received the study drug. Investigators observed a significant difference in median time to catheter failure in the intent-to-treat (ITT) and modified ITT populations (P≤0.0006). Catheters were successfully retained in 57% of patients in the MLT arm versus 38% in the standard-of-care arm (P=0.0025).
Clinical and microbiological failure related to the catheter or CLABSI were significantly higher in the standard-of-care group (P=0.006 and P=0.012, respectively). Adverse events, serious adverse events, and all-cause mortality were comparable for the two groups. There were no drug-related serious adverse events.
“The outcome was really way more than what we expected,” Dr. Raad said. “This triple combination was significantly better not only clinically, not only with the primary objectives, but all the secondary objectives, and it was effective independently in the hemodialysis patient population and the non-hemodialysis, mainly cancer patient population.”
Dr. Chaftari and Dr. Raad receive grant/research support from Citius Pharmaceuticals, manufacturers of Mino-Lok and is also an owner and has a patent with Spectrum Vascular.
