A Belgian biotech company says it is advancing a new approach to one of the world’s most dangerous drug-resistant pathogens, as the World Health Organization releases new product profiles targeting urgently needed antibiotics.
Obulytix, a Belgian biotech firm, has announced that it is developing a new class of antibacterial therapies targeting multidrug-resistant Gram-negative bacteria, including Acinetobacter baumannii – one of the organisms highlighted in the updated WHO guideline.
The profiles define the desired characteristics for antibiotic candidates designed to treat three critical categories of infection: severe multidrug-resistant gram-negative infections; resistant Gram-positive infections in immunocompromised or critically ill patients; and bacterial meningitis.
Special attention is paid to carbapenem resistance A. baumannii, Pseudomonas aeruginosa and resistant Enterobacterales, which are responsible for some of the most serious hospital-acquired infections, including bloodstream infections and ventilator-associated pneumonia.
Despite approximately 90 antibacterial agents currently in global preclinical or clinical development, WHO said relatively few agents target these high-priority pathogens and even fewer represent “truly innovative” mechanisms of action.
“The scientific community has developed and approved new antibiotics in recent years. This is good, but unfortunately not enough to catch up with emerging drug-resistant bacteria, especially against those of greatest concern,” said Dr Yvan Hutin, director of antimicrobial resistance at WHO. “We need a reliable pipeline of new antibacterial agents that are innovative, affordable and accessible to everyone who needs them.”
Targeting a high priority threat
Obulytix says its flagship program is directly focused on one of WHO’s most pressing concerns. “Obulytix’s lead program directly targets multidrug-resistant Acinetobacter baumannii, one of WHO’s highest priority gram-negative pathogens,” chief executive Kristof Van Emelen told Euractiv.
The company is engineering Precision Lysin Therapeutics (PLTs), bacteriophage-derived enzymes designed to degrade bacterial cell walls.
“Lysine-based therapeutics represent a truly new class of antibacterials,” the company said. “Unlike traditional antibiotics, our PLTs enzymatically degrade the bacterial cell wall with rapid and irreversible killing.”
According to Obulytix, the approach can bypass “classical resistance mechanisms such as β-lactamases, porin loss or efflux pumps,” offering what he calls “a fundamentally different way of treating multidrug-resistant infections.”
Long scientific challenge
Gram-negative bacteria have long been one of the most difficult frontiers in antimicrobial research. Their outer membrane acts as a barrier that prevents many drugs from entering the cell, contributing to decades of stagnation in new classes of antibiotics that can work against them.
Engineering lysines to penetrate this barrier has historically proven difficult, with many attempts failing to demonstrate sustained activity under physiological conditions.
Obulytix says its engineered lysines have shown bactericidal activity in high-serum environments, characteristic of severe infections such as septicemia. The company reports activity against A. baumannii in laboratory studies, as well as reductions in bacterial load in mouse models of bloodstream infection.
The company argues that the likelihood of developing resistance to lysines is lower than with traditional antibiotics and that the molecules can be used either with existing therapies or independently.
“PLTs show synergy with standard-of-care antibiotics, enabling their use as adjunctive therapy to increase efficacy and potentially extend the clinical life cycle of existing regimens,” the company said. “They also have potential as a stand-alone therapy in severe gram-negative bloodstream or pulmonary infections.”
Innovation collides with economic constraints
The scientific progress comes against a backdrop of a market that health agencies warn remains structurally ill-suited to support antibiotic innovation. Because new antibiotics must be used sparingly to maintain their effectiveness, companies face weak commercial incentives even when they address key societal needs.
European policymakers are seeking to redress this imbalance through mechanisms such as transferable exclusivity vouchers and through reforms in EU pharmaceutical legislation. But developers say further measures will be required to bring first-class agents through late-stage trials.
“There is still a significant gap between early scientific excellence and late-stage development support,” Obulytix said. “For companies developing first-in-class therapies against priority pathogens such as multidrug-resistant A. baumannii, predictable withdrawal incentives and coordinated EU-wide subscription models will be essential.”
In a press release, she warned that Europe remains “in the middle of transition” in building a sustainable economic environment for antibiotic innovation. “Scientific readiness is high; economic readiness still needs strengthening,” he said, adding that “an updated European framework is needed to have a truly lasting impact.”
Belgium seeks to tighten domestic response
The global push for new antibiotics coincides with Belgium’s efforts to strengthen its national strategy on antimicrobial resistance. A draft plan for 2026-2030 proposes linking part of hospital funding to performance in infection prevention and antibiotic stewardship – a shift towards incentive-based accountability.
Authorities are now reviewing submissions from the public consultation before finalizing the strategy for political approval. If approved, the plan will introduce new performance indicators, standards and transparency tools aimed at changing prescribing habits and strengthening infection control practices as Belgium works to meet EU targets for antibiotic use.
(VA, BM)
