The study is being conducted at Karolinska University Hospital Huddinge and Uddevalla Hospital. The treatment lasts for a total of 14 weeks with 2 doses per month. Three dose levels are being studied. The Principal Investigator (PI) is Dr Katarina Uttervall, MD, PhD, Department of Hematology/HERM, Karolinska University Hospital Huddinge. Analysis of biomarkers takes place at the Central Laboratory, Karolinska University Hospital Solna, NKS. Inclusion criteria include adult MM patients with relapsed treatment-resistant disease, who received 1-5 prior lines of therapy. The primary objective is to confirm safety and tolerability and with a secondary objective to determine indications of treatment response.

The follow-up shows interesting results. At the first follow-up after completion of treatment, all patients in dose group 1, (four patients, 3mg/kg) have stable disease. The patients have then been followed, without other cancer treatment, until new progression of the disease (according to the amendment). Time to progress was 89 days, 59 days, 188 days and 39 days. None of the patients had any significant side effects from the ODX treatment. The results indicate that ODX is effective against multiple myeloma and that the slowing effect persists over time without other treatment.

For more information about DexTech, please contact:

Gösta Lundgren - CFO

DexTech Medical AB

Phone: +46 (0) 707104788

E-mail: gosta.lundgren@dextechmedical.com

This information is information that DexTech Medical AB 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, on April 23, 2025.

DexTech Medical AB is a Swedish research company that, based on its technology platform, has developed four drug candidates that are protected by patents. The lead candidate is OsteoDex for the treatment of castration-resistant prostate cancer (CRPC) with bone metastases. A successful clinical phase II study has been conducted with OsteoDex where the results show high tolerability with mild side effects as well as treatment effect on patients who fail existing drugs. DexTech's goal is to out-license each drug candidate no later than after completion of the phase II study. DexTech Medical AB is listed on the Spotlight Stock Market.