The first, to our knowledge, clinical trial testing an RSK inhibitor in cancer patients was announced in November 2019: Pheonix Molecular Designs initiated a Phase 1/1b clinical trial to evaluate the safety and tolerability of PMD-026 in patients with metastatic Bca and Triple Negative Breast Cancer (Clinical Trials ID: NCT04115306). This evidence concerns the gene RPS6KA3 and breast cancer.