Immunotherapy for pleural mesothelioma: from innovation to the frontlines of core clinical questions

In August 2018, Japan's Pharmaceuticals and Medical Devices Agency (PMDA) became the first in the world to approve immune checkpoint inhibitor (ICI) monotherapy with nivolumab for previously treated, unresectable, advanced, or recurrent pleural mesothelioma (PM), setting a global precedent. Subsequently, in October 2020, the U.S. Food and Drug Administration (FDA) approved the combination of nivolumab and ipilimumab (CheckMate 743 trial) as the first-line treatment for unresectable PM. This marked the first update to standard first-line therapy in approximately 15 years since the approval of cisplatin (CDDP) plus pemetrexed (PEM) based on the EMPHACIS trial in 2004. Most recently, in September 2024, the FDA approved pembrolizumab plus platinum and PEM (KEYNOTE-483 trial) as another first-line option for advanced or metastatic PM. These developments underscore the rapid evolution of systemic therapy for PM. However, several urgent clinical questions have emerged in real-world practice. This article aims to address these issues based on the latest evidence and expert insights.