The issue of "antibiotic resistance," in which bacteria adapt to antibiotics and drugs no longer work properly, is emerging as a major topic in the global medical community. In response, research and development to find new treatments that supplement or replace existing antibiotics is gaining momentum.
According to the Korea Disease Control and Prevention Agency, deaths related to antibiotic resistance in Korea were estimated at 22,700 in 2021 and are expected to reach 32,400 in 2030. According to the World Health Organization (WHO), as of Feb. 2025 there were 90 antibacterial candidates in clinical or preclinical stages worldwide. However, only 15 of them was found to be innovative.
In Korea, the genome-based microbial diagnostics corporations Sanigen(188260) has thrown its hat in the ring to develop next-generation antibacterials to overcome antibiotic resistance. The company was selected as the lead institution for a follow-up research and development project under the Ministry of Science and ICT's national program "K-HERO," and has begun in earnest to discover candidate substances.
Sanigen on the 28th held the "2026 endolysin-based next-generation antibacterial symposium" at Jeongdong 1928 Art Center in Jung-gu, Seoul, and unveiled its research and development (R&D) roadmap.
It presented an approach that departs from the conventional method of screening antibacterial substances found in nature, instead using artificial intelligence (AI) and biofoundry technologies to create new endolysins. A biofoundry is an automated research system that uses AI and robots to mass-produce and test genetically designed proteins or microorganisms.
◇ A "natural weapon" that targets antibiotic-resistant bacteria
The substance Sanigen highlighted is "endolysin."
Endolysin is an enzyme protein used by bacteriophages, viruses that infect bacteria, when they kill bacteria. After bacteriophages replicate inside bacteria and exit, they break down the bacterial cell wall with endolysin.
Yoo Sang-yeol, senior scientific adviser at Sanigen and a former Seoul National University professor, said in a presentation that "because bacteriophages attack bacteria in a way entirely different from antibiotics, antibiotic-resistant bacteria can also be targeted." This means that even bacteria that have acquired resistance to antibiotics can be attacked by phages if the surface receptors recognized by phages are maintained.
Endolysin is drawing attention as an alternative because its mechanism of killing bacteria is fundamentally different from that of existing antibiotics. Bacteriophages do not infect animal or plant cells, a characteristic that has raised the possibility of developing them into new antibacterial therapies.
However, there are still no cases of therapies using endolysin that have been commercialized. The endolysin candidate "CF-301 (exebacase)" developed by the U.S. biotech company ContraFect showed potential in early clinical trials, but the phase 3 trial was terminated early after failing to demonstrate efficacy.
A limitation of naturally occurring endolysins is that their bactericidal power is constrained so that bacteriophages do not kill their host bacteria too quickly. In the human body, their activity can decline due to the effects of proteases or blood components.
◇ Selected as a national "K-HERO" project… targeting gram-positive bacteria
Sanigen plans to overcome these limitations with "second-generation chimeric endolysin" technology.
Yoo Sang-yeol, Sanigen's senior scientific adviser, said, "To be used as a therapy, higher activity than natural endolysins is needed, and it must operate stably in the human body," adding, "Solving these two problems is the key to commercialization."
The conventional first-generation approach was to mass-collect bacteriophages from nature and then identify highly performing endolysins within them.
Sanigen plans to combine domains using its strain and genome databases and design them with AI for greater bactericidal power and stability. The designed proteins will be rapidly produced in the biofoundry and their performance verified. The company said that among the resulting candidates, those with strong bactericidal effects will be selected and then revalidated in environments similar to the human body.
Sanigen's "K-HERO" research project will run for 42 months from July 2026 to Dec. 2029. The total project budget is 3.5868 billion won, of which government research funding is 3.15 billion won. The company plans to push ahead with endolysin drug development up to the preclinical-to-clinical entry stage through the national project.
The first target is gram-positive resistant bacteria. Sanigen plans to develop candidates targeting Staphylococcus, Enterococcus, and Streptococcus. These bacteria are regarded as major pathogenic bacteria that cause conditions such as sepsis.
Park Jeong-ung, Sanigen's CEO, said, "We will pursue second-generation endolysin development based on the candidates and bacteriophage research experience secured during first-generation endolysin development," adding, "The core of this project is not merely finding substances that exist in nature but designing proteins with desired properties using AI."
However, as there have been cases where development was halted because the efficacy of endolysin candidates fell short during actual clinical development, the key task will be to link the antibacterial activity confirmed in preclinical studies to clinical efficacy going forward.
Kim Min-sik, a professor in the Department of Food and Nutrition at Yonsei University who presented at the symposium, said, "To target gram-negative bacteria, a separate strategy is needed to penetrate the outer membrane and deliver endolysin."
CEO Park Jeong-ung said, "Having secured a stable cash generation base through our existing diagnostics business, we plan to make molecular diagnostics even more convenient while entering the high–value-added biopharmaceutical market centered on endolysin."
Founded in 2005, Sanigen has commercialized about 150 molecular diagnostic products that test for foodborne pathogens and other targets, and it holds more than 10,000 strains and over 20,000 genomic data entries. The company's strategy is to use the microbial genome data and strain library obtained from its existing diagnostics business for new drug development.