GSK’s Risvutatug Rezetecan Receives FDA Orphan Drug Designation for Small-Cell Lung Cancer

GSK plc (LON: GSK) announced that its B7-H3-targeted antibody-drug conjugate, risvutatug rezetecan, has been granted Orphan Drug Designation (ODD) by the US Food and Drug Administration (FDA) for the treatment of small-cell lung cancer (SCLC).

This regulatory milestone, the fifth for this drug, underscores the potential of risvutatug rezetecan in addressing cancers with limited treatment options.

The FDA's decision was supported by early clinical data from the phase I ARTEMIS-001 trial, which demonstrated durable responses in patients with extensive stage SCLC (ES-SCLC) treated with risvutatug rezetecan. ES-SCLC is a particularly aggressive form of lung cancer, accounting for about 70% of all SCLC cases, characterized by high relapse rates, few treatment options, and a poor prognosis. The five-year survival rate for ES-SCLC is approximately 3%, with most patients relapsing after initial treatment.

The median overall survival with standard-of-care treatments for relapsed ES-SCLC is approximately 8 months. This highlights the urgent need for new therapeutic options, a gap that risvutatug rezetecan aims to fill. The Orphan Drug Designation provides GSK with potential benefits, including market exclusivity upon approval, tax credits for qualified clinical trials, and exemption from certain FDA fees.

This designation follows the recent ODD granted by the European Medicines Agency (EMA) for risvutatug rezetecan in the treatment of pulmonary neuroendocrine carcinoma, which includes SCLC.

The drug has also received Priority Medicines (PRIME) Designation from the EMA for relapsed or refractory ES-SCLC and Breakthrough Therapy Designations from the US FDA for relapsed or refractory ES-SCLC and relapsed or refractory osteosarcoma. These designations are indicative of the drug's potential and the regulatory agencies' recognition of the unmet need in these cancer types.

GSK is actively developing risvutatug rezetecan in a range of solid tumors, including lung, prostate, and colorectal cancers. The B7-H3 target is expressed in a variety of solid tumors, making it an attractive target for antibody-drug conjugates. The company's strategy is to accelerate the development of risvutatug rezetecan in solid tumors with transformational potential.