Our immune system is an intricate apparatus that detects and destroys disease-causing agents, such as bacteria, viruses and abnormal cells. Antibodies constitute an important component of the immune system. When an antibody binds to a molecular target (“antigen”) on the disease-causing agent, it triggers its destruction. This affinity of antibodies for their target has been harnessed to develop lab-made antibodies to treat and diagnose disease. Nowhere has their impact been greater than in the field of oncology, where monoclonal antibodies are deployed to bind to antigens present on tumours and facilitate their eradication. Single-domain antibodies are about 10 times smaller than monoclonal antibodies, significantly simplifying engineering and production. Moreover, single-domain antibodies can bind to previously unreachable antigens and are more rapidly eliminated from the body, providing an added benefit when applied for diagnostic purposes. And that is where ABSCINT, a spin-off of the Vrije Universiteit Brussel (VUB), is emerging as a new player in the field. ABSCINT is developing single-domain antibodies for disease diagnosis through imaging. When labelled with a miniscule amount of radioactive material, ABSCINT’s antibodies can visualize specific antigens (and thus cells) in patients undergoing a PET/CT scan.

ABSCINT´s story started in the laboratory of Prof. Tony Lahoutte, Chief of the Nuclear Medicine department at University Hospital Brussels and head of the VUB´s Molecular Imaging Research Unit. Early on in his career at the VUB, Tony became fascinated by the single-domain antibody technology and its game-changing potential for medical diagnosis and treatment when combined with radioactivity. And so he started engineering radioactively-labelled single-domain antibodies that target antigens relevant to human disease. One of the first molecular targets his lab focused on was HER2, a protein promoting cancer cell growth and shown to be highly abundant in about 20% of breast cancer patients (“HER2-positive patients”). The results of the research with the HER2 probe were promising and prompted further testing in patients.

The lab had also started developing antibodies that could detect other molecular targets, including CD-206. CD-206 is a marker for macrophages, a type of immune cells. Accurately detecting macrophages turned out to be of utmost importance for patients suffering from sarcoidosis. Sarcoidosis is a disease characterized by the growth of groups of immune cells (including macrophages) all over the body, resulting in organ damage. When these cell clumps develop in the heart (“cardiac sarcoidosis”), they can inflict serious harm and even lead to sudden cardiac death. Currently, there is no easy and accurate way to detect the presence of these cell clumps in the hearts of sarcoidosis patients. This hinders diagnosis, and therefore prevents appropriate treatment. The CD-206 antibody that Tony´s lab developed could prove to be the answer to this unmet clinical need.

If we can bring these probes to the market, we really can create an impact. There is little use in helping or saving a patient in our hospital and then just publishing it.

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To drive the diagnostic HER2 and CD-206 probes into the clinic, ABSCINT was created in 2020. As Tony explains “You need all three - the lab, the clinic and industry - to build something from idea to reality. If we can bring these probes to the market, we really can create an impact. There is little use in helping or saving a patient in our hospital and then just publishing it. We really want to develop  something that breaks through, has a broader application and could benefit many.” And that is where Karine Clauwaert came into the picture. In her role as ABSCINT´s CEO, Karine can draw upon her extensive experience in business development, but also harness her expertise in the manufacturing requirements for clinical products (“CMC”). Any product that will be administered to patients needs to be consistently produced and adhering to high quality standards. Once the CMC process for both the HER2 and CD-206 antibodies is streamlined, more extensive clinical trials to demonstrate the efficacy of these probes as diagnostic tools will be performed.

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We want to enable systematic screening for HER2 positivity in the brain, so that treatment can be initiated before symptoms develop and its efficacy can accurately be determined.

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The first application for the HER2 antibody that the company will extensively test in the clinic is the detection of brain metastases in HER2-positive cancer patients. Around 45% of HER2-positive patients develop brain metastases and could thus potentially benefit from ABSCINT´s technology. According to Karine “At present, there is a lack of systematic screening of HER2-positive patients to detect potential brain metastases. And so usually doctors do not start treatment until the patient develops symptoms. We want to enable systematic screening for HER2 positivity in the brain, so that treatment can be initiated before symptoms develop and its efficacy can accurately be determined.” The clinical validation of the CD-206 antibody for the diagnosis of cardiac sarcoidosis will run in parallel. Karine explains “Only 30% of cardiac sarcoidosis patients are properly diagnosed. Our antibody will allow to fish out these patients. A cardiologist can then follow them up more closely and treat them appropriately to prevent sudden death. It is really a disease in which you can save lives.”

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By asking critical questions, Qbic really strengthened the project, which materialized in being awarded the BioWin grant.

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To push ABSCINT forward, Karine and Tony surrounded themselves with a stellar team. Their well-rounded group can draw upon a broad spectrum of past professional experiences, and its diversity makes for a very complementary team. Besides an excellent team, also more funding was needed. Therefore, they applied for a substantial grant from BioWin. When they felt they were getting traction, they approached Qbic to bolster the application and raise additional funds. Karine elaborates “They were pieces of a puzzle that came together. By asking critical questions, Qbic really strengthened the project, which materialized in being awarded the BioWin grant.” From Tony´s perspective, “It has been a very fair and open discussion for the first steps of the spin-off. Trust is very important, basically it is a long-term relationship. And I only want to work with investors that understand in depth what they are investing in, because then you have something that you can build upon.”

For ABSCINT, it is only getting started. Karine muses “In the long run, we want to have multiple single-domain antibodies for diagnosis of a variety of diseases in our pipeline. Our aim is to be shipping out our kits around the world for a variety of applications, so that the nuclear medicine departments just need to open their fridge and decide which ABSCINT kit they will use for their patient.”