Ariceum's Radioligand Therapy Enters Trials for Rare, Aggressive Cancers

Ariceum Therapeutics, a leading biopharmaceutical company, has announced a significant milestone in its efforts to address rare and aggressive cancers. The company has dosed the first patient in the SANTANA-225 Phase I/II clinical trial for its investigational radioligand therapy, 225Ac-SSO110.

The trial is designed to assess the preliminary efficacy, safety, and tolerability of 225Ac-SSO110, which is an Actinium-225-labeled somatostatin type 2 receptor (SSTR2) antagonist. This innovative therapy is being developed for the treatment of Merkel cell carcinoma (MCC) and extensive-stage small cell lung cancer (ES-SCLC), two highly aggressive cancer types with significant unmet medical needs.

The open-label, global SANTANA-225 study will initially include a dose escalation phase with 20 participants, followed by expansion cohorts as the trial progresses. The goal is to establish the recommended dose for the Phase II portion of the study, which will further evaluate the therapy's efficacy and safety.

Ariceum Therapeutics' chief medical officer, Germo Gericke, expressed excitement about the milestone, stating that radioligand therapies are redefining precision oncology by enabling the targeted delivery of radiation directly to tumor cells while minimizing exposure to healthy tissue. He believes that 225Ac-SSO110 has the potential to address the urgent needs of patients with these challenging cancers.

The company plans to release initial safety results from the SANTANA-225 trial in 2026, which could support the expansion of the therapy into additional neuroendocrine tumor indications and further validate its distinct mechanism of action.