Nuvalent, Inc. announced that the first patient has been dosed in ARROS-1, its Phase 1/2 clinical trial evaluating NVL-520 in patients with advanced ROS1-positive non-small cell lung cancer (NSCLC) and other advanced solid tumors. NVL-520, Nuvalent's lead product candidate, is a novel ROS1-selective inhibitor designed to address the clinical challenges of emergent treatment resistance, CNS adverse events, and brain metastases that may limit the use of currently available ROS1 kinase inhibitors. ARROS-1 is a Phase 1/2, multicenter, open-label, dose-escalation and expansion trial evaluating NVL-520 as an oral monotherapy.

The Phase 1 dose-escalation portion of the study is open and enrolling patients with advanced ROS1-positive solid tumors who have been previously treated with at least one prior ROS1 tyrosine kinase inhibitor (TKI) therapy, and will evaluate the overall safety and tolerability of NVL-520 as well as determine the recommended Phase 2 dose (RP2D), characterize the pharmacokinetic profile, and evaluate preliminary anti-tumor activity. Once a safe and tolerable dose is determined as the RP2D, the trial is designed to transition directly into the Phase 2 multiple cohort expansion portion, which will evaluate the overall activity of NVL-520 in patients with advanced ROS1-positive NSCLC and other advanced solid tumors. The Phase 2 portion will examine several cohorts of patients based on the number and type of prior anti-cancer therapies they have received.

The Phase 2 cohorts are designed to support potential registration in ROS1-positive patients with NSCLC who are kinase inhibitor-naïve and in those who have been previously treated with ROS1 kinase inhibitors. In addition to NVL-520, Nuvalent is advancing a robust pipeline including the development of NVL-655 as a parallel lead program for the potential treatment of patients with ALK-positive NSCLC, along with multiple discovery-stage research programs.