GSK has received breakthrough therapy designation from the US FDA for its investigational antibody-drug conjugate GSK5764227, aimed at treating relapsed or refractory extensive-stage small-cell lung cancer. This designation accelerates the review process due to promising early clinical evidence, particularly from a Phase 1 trial showing significant disease control in heavily pre-treated patients. Approximately 70% of small-cell lung cancer cases are extensive-stage, with a low five-year survival rate of about 3%, highlighting the urgent need for new treatments. GSK acquired the global rights to GSK5764227 from Hansoh Pharma earlier this year, and plans to commence global Phase 1/2 trials in the second half of 2024. The FDA's approval is based on data from ongoing trials that include over 200 patients, and results will be presented at the upcoming World Conference on Lung Cancer in September.