GSK's Risvutatug Rezetecan Gets FDA's Orphan Drug Tag in Lung Cancer

GSK plc GSK announced that the FDA has granted Orphan Drug Designation to GSK’227, its investigational B7-H3-targeted antibody-drug conjugate (“ADC”), for the treatment of small-cell lung cancer (SCLC). GSK’227 has now been renamed risvutatug rezetecan.

Orphan Drug Designation (“ODD”) is a special status granted by the FDA to promote new drugs or indications for existing drugs to treat, prevent or diagnose rare diseases affecting a small percentage of the population (fewer than 200,000 people).

The ODD was based on positive data from the phase I ARTEMIS-001 study, which showed durable responses in patients with extensive-stage SCLC.

A phase III study evaluating risvutatug rezetecan in relapsed SCLC began in October 2025. Another phase III study is evaluating the drug for osteosarcoma, a rare and aggressive bone cancer. Early-stage studies are underway to assess its potential in several other cancers, such as non-small-cell lung cancer, head and neck cancer, prostate cancer and other cancers.

In the past year, GSK’s shares have surged 41.7% compared with the industry’s 11.6% rise.

Risvutatug rezetecan has received several other expedited designations to accelerate its development and regulatory review in solid tumors with transformational potential. In October, the European Medicines Agency (EMA) granted ODD to risvutatug rezetecan for the treatment of pulmonary neuroendocrine carcinoma, which includes SCLC. Previously, the EMA awarded PRIME designation for relapsed or refractory extensive-stage SCLC. The drug also earned the FDA’s Breakthrough Therapy Designation for relapsed or refractory ES-SCLC and osteosarcoma.

Small-cell lung cancer is a rare,fast-growing lung cancer that starts in lung neuroendocrine cells, spreading quickly to the brain, liver, and adrenals. In the United States, SCLC constitutes about 13% of all lung cancers. It has one of the poorest prognoses among major cancers. Most patients with ES-SCLC relapse after initial treatment, with survival times often measured in months rather than years.

GSK licensed exclusive global rights (excluding the Chinese mainland) to risvutatug rezetecan from Chinese biotech Hansoh Pharma in December 2023.

GSK’s Zacks Rank & Stocks to Consider

GSK currently carries a Zacks Rank #3 (Hold).

Some better-ranked stocks in the biotech sector are ANI Pharmaceuticals ANIP, CorMedix CRMD and Castle Biosciences CSTL. ANIP, CRMD and CSTL currently sport a Zacks Rank #1 (Strong Buy). You can see the complete list of today’s Zacks #1 Rank stocks here.

In the past 60 days, estimates for ANI Pharmaceuticals’ 2025 earnings per share (EPS) have increased from $7.29 to $7.54. During the same time, EPS estimates for 2026 have moved up from $7.79 to $8.15. In the past year, shares of ANIP have surged 45.1%.

ANI Pharmaceuticals’ earnings beat estimates in each of the trailing four quarters, delivering an average surprise of 21.24%.

In the past 60 days, estimates for CorMedix’s 2025 EPS have increased from $1.85 to $2.87. EPS estimates for 2026 have moved up from $2.49 to $2.88 during the same period. CRMD stock has surged 30.7% in the past year.

CorMedix’s earnings beat estimates in each of the trailing four quarters, with the average surprise being 27.04%.

In the past 60 days, the loss estimate for Castle Biosciences has narrowed from 65 cents to 34 cents in 2025. During the same period, loss estimates for 2026 have improved from $2.10 to $1.06. CSTL stock has rallied 30.6% over the past year.

Castle Biosciences’ earnings beat estimates in three of the trailing four quarters and missed in the remaining quarter with the average surprise being 66.11%.

Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report

This article originally published on Zacks Investment Research (zacks.com).

Zacks Investment Research