Image: Karaja

Published on 08/11/2025

By Roseli Andrion  |  Agência FAPESP – At a time when bacterial resistance to traditional drugs is raising alarms globally, Brazilian startup Karaja Biosciences has an innovative proposal rooted in sophisticated science: fighting bovine infections with bacteriophages, or phages. These are highly specific viruses that attack only one species or group of bacteria without affecting animal or human cells.

The solution has existed in nature for billions of years and was chosen by the company to prevent mastitis in dairy herds – a disease that affects nearly half of the cows in the country and causes enormous economic losses. One of the main advantages of bacteriophages over antibiotics is their characteristic specificity: unlike antibiotics, which affect beneficial microbiota, bacteriophages allow for targeted treatment without side effects.

Luciano Queiroz, the CEO and founder of Karaja, explains that bacteriophages specifically infect and kill bacteria without infecting other types of cells. “There are at least two phages for every bacterium in the world. There are still many phages to be discovered. It’s a huge diversity, representing a vast universe of therapeutic possibilities.”

The researcher identified a bacteriophage that is highly effective against Staphylococcus aureus, one of the bacteria that most affects dairy cows. He then decided to work on developing solutions to transform the way diseases are treated in livestock farming. To accomplish this, he began by developing a product to prevent mastitis in herds, which is one of the biggest challenges in the dairy industry.

Food safety

Mastitis is the inflammation of the mammary glands, which can be caused by over 100 types of bacteria. The disease can present clinically, with visible symptoms, or subclinically, without apparent signs. According to industry data, approximately 10% of the herd has clinical mastitis, while 45% develops the subclinical form. “It’s a very complex problem because it’s caused by different pathogens. Each location will have a different cause,” says Queiroz.

The disease can be contagious and transmitted between animals or environmental and originating from the place where they live. Traditional treatment involves applying antibiotics directly to the mammary gland. This can cause two main problems: the milk produced during treatment cannot be sold because it contains drug residues, and there is a risk of the development of antibiotic-resistant bacteria. Bacterial resistance to antibiotics is a major threat to global health because it compromises food safety.

Therefore, good management is essential to preventing infection. This includes cleaning the environment, practicing proper hygiene during milking, and maintaining facilities appropriately. “Even with high production levels, it’s possible to keep the herd healthy with proper management,” he says.

Karaja’s first product is an environmental sanitizer for spaces where animals live, especially their beds and other structures in dairy farm stables. It is currently at Technology Readiness Level 4 (TRL4) and has been proven effective in vitro. The company plans to move forward with animal testing in the coming months. “Within a year and a half or two years, we should have this product ready for the market,” Queiroz projects.

Karaja is one of the first companies in Brazil to invest in this biotechnology for use in livestock farming. The market is promising: Brazil has more than 230 million head of cattle, in addition to over 1 billion poultry and millions of pigs (both sectors can also benefit from similar solutions). “Since rural producers already face many challenges, our solutions need to be effective and easy to apply. The idea is to make biotechnology accessible and integrate it into the routine of the field.”

Additionally, the product is appealing in light of the growing debate about the indiscriminate use of antibiotics in livestock farming. The presence of drug residues in milk can affect consumer health, cause significant losses for producers, and accelerate the emergence of resistant bacteria. This makes it more difficult to treat infections in humans and animals.

Research and development

Karaja currently has a library of over 150 bacteriophages and is developing an artificial intelligence-powered bioinformatics platform to speed up the identification of the most effective organisms against each bacterium. “We will insert the genomic sequencing of the bacterium, which will then be analyzed and compared with the genomes of our phages to determine which one can kill it,” he explains.

Thus, rather than testing all bacteriophages in the laboratory, the company can swiftly identify the most effective ones against a specific bacterium. This significantly speeds up the development process, reduces costs, and enables a faster response to market demands. The startup’s goal is to become a national leader in bacteriophage biotechnology.

The project, supported by FAPESP’s Innovative Research in Small Businesses Program (PIPE), is aligned with the concept of “one health,” which connects human, animal, and environmental health. “When we think about mastitis, the antibiotic applied intramammary can remain present for up to ten days, depending on the medication used. Milk collected during this period must be discarded, because it’s necessary to avoid antibiotics in the chain as much as possible.”

This, in addition to economic losses for producers, contributes to the development of resistant bacteria that can affect human health. “We’re living in a time when antibiotics are no longer working because bacteria are developing resistance.” Alongside its work with dairy cattle, the company has identified opportunities in pig and poultry farming. “We think a lot about animal nutrition and the prevention of diarrhea in animals,” reveals Queiroz.

Future

In addition to prevention products, the company plans to develop drugs to treat infections. It is already investing in synthetic biology to create genetically modified bacteriophages with greater efficacy. “We can synthesize a protein that breaks down the cell wall of the bacteria. This way, it’ll have the same activity, but it won’t multiply,” explains the researcher.

Queiroz believes it is possible to expand to other countries, but acknowledges that the products will need to be adapted to each region. “The bacteria that cause mastitis in Argentina or some other country, for example, are different from those here in Brazil, and the solution needs to be adjusted for local varieties,” he points out.

The startup is exploring applications in other sectors as well, including agriculture, cosmetic treatments, and food packaging. “We want to do world-class science. There are no boundaries to knowledge when you have structure and dedication.”

Queiroz emphasizes that the company constantly invests in research and development and maintains a scientific mindset. “We have to be vigilant because it’s a competitive market,” he believes. In order to become an entrepreneur, he had to learn about business models, regulations, and the market. “Despite the shock of leaving my Ph.D. program and diving into the business world, my scientific mindset helps. We know how to test, validate, and investigate. All of this is essential for a startup.”

 

Source: https://agencia.fapesp.br/55571