The US Food and Drug Administration (FDA) has granted Orphan Drug Designation (ODD) to Ariceum Therapeutics’ 225Ac-SSO110 (satoreotide) for the treatment of patients with small cell lung cancer (SCLC). 

Ariceum has announced plans to commence Phase I/II human clinical development of 225Ac-satoreotide under the trial name, SANTANA-225 in Q1 2025. 

Manfred Rüdiger, Chief Executive Officer at Ariceum Therapeutics, said: “Receiving ODD for 225Ac-satoreotide is a recognition of its potential as a treatment option for patients with SCLC and an important regulatory milestone for Ariceum. The FDA’s ODD will support our objective to accelerate the development of 225Ac-satoreotide through human trials to provide a potentially life-saving therapy to patients with limited alternatives.” 

Listen to the DDW Podcast with Manfred Rüdiger. 

SSO110 (satoreotide) labelled with Lutetium-177 (177Lu) and Actinium-255 (255Ac) is an antagonist of the somatostatin type 2 (SSTR2) receptor which is overexpressed in aggressive neuroendocrine tumours (NETs) such as small cell lung cancer (SCLC) or Merkel Cell Carcinoma (MCC), all of which have limited treatment options and poor prognosis.  

In October 2024, Ariceum published preclinical data demonstrating the significant potential of 225Ac-satoreotide to outperform SSTR2 targeting agonists.  

225Ac-satoreotide showed a high frequency of complete durable responses and 100% survival supporting advanced clinical development in SCLC, MCC, and other aggressive cancers.  

225Ac-satoreotide in combination with its companion patient selection tracer 68Ga-SSO120 is being developed as a ‘theranostic pair’ for the combined diagnosis and targeted radionuclide treatment of multiple indications expressing SSTR2, such as SCLC, MCC, and other aggressive, hard-to-treat cancers. 

Ariceum is also developing a radiolabelled PARP-inhibitor (ATT001), currently in Phase I clinical development under the trial name CITADEL-123. ATT001 was part of the acquisition of Theragnostics which was closed in June 2023.

Diana Spencer, Senior Digital Content Editor, DDW