GSK’s $10.6 billion acquisition of Nuvalent began paying off as the FDA approved zidesamtinib—branded Jideytro—for ROS1-positive metastatic non-small cell lung cancer in patients previously treated with a ROS1 kinase inhibitor. The approval arrived roughly a week after GSK closed the Nuvalent deal and earlier than an expected FDA decision timeline, following breakthrough therapy and orphan drug designations that can accelerate review. Analysts will now pivot to commercial modeling given that existing ROS1 therapies have struggled to scale. GSK is also leveraging the Nuvalent platform beyond Jideytro, with another Nuvalent medicine, neladalkib, still under FDA review. The regulatory win strengthens GSK’s stated oncology push and raises the bar for subsequent readouts across the acquired pipeline.