Clinical data from the CT-01 programme

Current Report No. 4/2026 

Date of preparation: 3 February 2026 

Subject: Clinical data from the CT-01 programme 

Legal basis: Article 17(1) of the MAR Regulation – confidential information 

The Management Board of Captor Therapeutics S.A. (the “Company”) announces that it has received and analysed data on further pharmacodynamic readings from the CT-01 clinical trial programme. 

To date, the drug candidate has been administered to one patient in the first cohort at a dose of 0.3 mg and to three patients in the second cohort at a dose of 0.6 mg. The Company has received approval from the patient safety monitoring committees to administer the drug candidate to three patients in the third cohort at a dose of 1.2 mg. The first administration in the third cohort is planned for 5 February 2026. 

One patient in the 0.6 mg cohort achieved a clinical benefit in the form of stable disease. The patient continues treatment. The Company considers this benefit encouraging, especially in the context of the effectiveness of drugs currently used to treat hepatocellular carcinoma and the burden of this disease. Targeted therapies currently used to treat hepatocellular carcinoma generally delay disease growth of tumor. 

All three patients in the 0.6 mg dose cohort showed an increase in biomarkers signalling induced cell death, i.e. ATF3 and DDIT3. The increase in ATF3 and DDIT3 biomarker levels significantly indicates the action of the drug candidate according to the assumed mechanism and signifies the transition of cells into a state of cellular stress (ATF3) and, consequently, onto an irreversible path of cell death (DDIT3). 

In addition to the mechanistic results in the form of increased levels of ATF3 and DDIT3 biomarkers, the Company has a CT scan image indicating tumour growth inhibition and stable disease. In another patient in cohort 2, a significant reduction in the inflammation biomarker CRP was observed, which may indicate the effect of the drug candidate on the second molecular target, NEK7. From cohort 3 onwards, the Company plans to perform liver biopsies, subject to patient consent. The biopsy will allow verification of the research assumption, i.e. the mechanism of action of the prodrug, by measuring the concentration of the active form of the drug candidate directly in liver cancer cells. According to our assumptions, the mechanism of action of the prodrug, ABS-752 (also known as CT-01 or CPT-6281), allows for a significant increase in the concentration of the active form of the drug in diseased liver tissue compared to its concentration in peripheral blood. The drug candidate is a so-called prodrug, which is converted into its active form by enzymes in the liver.  

No significant adverse effects have been observed to date. 

The company assesses the results of the mechanism of action and safety of the drug candidate as positive and promising, especially as they relate to doses that are considered subtherapeutic. 

The company notes that the results were achieved with the drug candidate administered to only four patients, so the data provided may not be sufficient to draw conclusions about the drug's action and possible side effects. 

The results described are presented in the appendix to this report.