GOTHENBURG, Sweden, November 10, 2026 – Isofol Medical AB (publ) (Nasdaq Stockholm: ISOFOL) today provides an update on the company’s ongoing phase Ib/II clinical study of arfolitixorin in patients with metastatic colorectal cancer. Preliminary results show that all patients evaluated to date have achieved disease control, with tumor shrinkage observed in a clear majority. During treatment, half of the treated patients have unexpectedly become candidates for tumor surgery. No dose-limiting side effects have been noted so far. The company has now decided to expand the phase II part of the study to additional sites and countries.
The information in the press release is intended for investors.
Isofol is developing arfolitixorin – a proprietary drug candidate designed to enhance the efficacy of established cancer treatments. In the currently ongoing clinical study, a new optimized dosing regimen of arfolitixorin is evaluated in combination with established cancer treatment in patients with metastatic colorectal cancer. The study is initially conducted at Charité – Universitätsmedizin Berlin.
The study is carried out in two stages. In phase Ib, safety and tolerability in escalating dose-levels is evaluated in patients with RAS-mutated metastatic colorectal cancer, a difficult-to-treat population. The study is currently evaluating the highest dose level, 500 mg/m2. So far, three patients have been enrolled at this dose level, and an additional three patients remain to be included. Once the safety evaluation is complete, the study’s Safety Review Committee can recommend dose levels for the subsequent phase II part.
Ahead of the upcoming subscription period for Isofol’s series TO2 warrant program, which runs between November 16–30, 2026, the company today provides an update on the ongoing open-label clinical study.
The evaluation includes patients from all dose levels:
- No dose-limiting side effects have been observed in any of the treated patients.
- Disease control has been achieved in all evaluated patients, and tumor shrinkage has been observed in a clear majority, with a reduction in the sum of measured tumor diameters of up to approximately 50 percent, according to RECIST 1.1 criteria.
- One of the ten treated patients, following an initial response and stable disease, subsequently experienced disease progression.
- Five of the ten patients treated to date discontinued study treatment after being assessed as candidates for tumor resection with curative intent, which was unexpected in this patient population in which surgery is not normally considered feasible.
“It is very encouraging that we continue to see promising results, with no dose-limiting toxicity noted. To see that five of a total of ten patients under the treatment have been selected as candidates for surgery is especially encouraging. Although the results are based on a limited patient population, they strengthen our confidence in the potential and provide motivation to continue evaluating arfolitixorin,” says Prof. M.D Sebastian Stintzing at Charité Universitätsmedizin and lead investigator in the study.
In connection with preparations for the initiation of the phase II part of the ongoing study, Isofol has decided to include more sites and to expand the study to additional countries than previously planned. The study is now planned to be conducted at 15–20 study sites in Germany, Spain, Austria and Greece. Through the collaboration with the Japanese pharmaceutical company Solasia Pharma K.K., patients in Japan will also be recruited in parallel in a so-called bridging study.
“I am very pleased with the strong interest in our study, and that so many renowned university hospitals want to participate. Expanding to more clinical sites and countries give us a broader geographic base and strengthens our ability to recruit patients. It is an important step to improve the conditions for a fast and efficient study,” says Dr. Roger Tell, Chief Medical Officer of Isofol.
Colorectal cancer is the third most common form of cancer globally, and the second most common cause of cancer-related death, according to the World Health Organization (WHO). The need for new treatments in the field is high.
For more information, please contact
Isofol Medical AB (publ)
Petter Segelman Lindqvist, Chief Executive Officer
E-mail: petter.s.lindqvist@isofolmedical.com
Phone: +46 (0) 739 60 12 56
This information is information that Isofol Medical AB (publ) is obliged to make public pursuant to the EU Market Abuse Regulation. The information was submitted for publication, through the agency of the contact person set out above, at 15:30 CET on November 10, 2026.
About Isofol
Isofol Medical AB (publ) is a clinical stage biotechnology company focused on improving outcomes for patients with severe forms of cancer. The company’s drug candidate arfolitixorin, a next generation folate treatment, is designed to enhance the efficacy of established standard treatments for several types of solid tumors. Arfolitixorin is currently being evaluated in phase Ib/II in colorectal cancer, the world’s third most common cancer, where there is a significant unmet medical need. Isofol is listed on Nasdaq Stockholm.
