GSK's Small Cell Lung Cancer Drug Receives US FDA Orphan Drug Designation

GSK plc announced on December 10, 2025, that its B7-H3-targeted antibody-drug conjugate, risvutatug rezetecan, has received Orphan Drug Designation (ODD) from the US Food and Drug Administration (FDA) for the treatment of small cell lung cancer (SCLC).

The designation was supported by preliminary clinical data demonstrating durable responses in patients with extensive-stage SCLC (ES-SCLC) treated in the Phase I ARTEMIS-001 trial. SCLC accounts for approximately 13% of lung cancer diagnoses in the US, with an estimated 29,500 new cases in 2025. The 5-year survival rate for extensive-stage SCLC is approximately 3%.

This is the fifth regulatory designation for risvutatug rezetecan, underscoring the potential of this B7-H3-targeted ADC, which is being developed across a range of solid tumors. The designation follows ODD granted by the European Medicines Agency (EMA) for pulmonary neuroendocrine carcinoma and several FDA Breakthrough Therapy Designations.

Risvutatug rezetecan is an investigational therapy composed of an antibody linked to a potent payload. GSK acquired worldwide rights to develop and commercialize the drug from Hansoh Pharma. A global Phase III trial for risvutatug rezetecan in relapsed ES-SCLC commenced in August 2025.