Pharmacodynamic proof of concept was demonstrated with Irosustat effecting nearly complete STS inhibition at three doses, and in all patients there was notable suppression of endocrine parameters.

[14] The multicentre IRIS trial, an open-label phase II clinical study, explored the clinical value of adding an STS inhibitor in addition to a first-line AI in patients with advanced breast cancer and enrolled postmenopausal women with ER+ locally advanced or metastatic breast cancer who had benefited from a first-line AI but were subsequently progressing.

Importantly, these data are the first to demonstrate clinical activity of Irosustat in early breast cancer, albeit in a small patient population.

Irosustat was also evaluated as a combination therapy with an oral epidermal growth factor receptor tyrosine kinase inhibitor for the treatment of Non-Small Cell Lung Cancer Patients.

[1] Importantly, it was demonstrated [17] that oral treatment with Irosustat alleviates the symptoms of Alzheimer’s Disease in a murine model, indicating that the drug passes the blood–brain barrier.