[Image courtesy of GSK]

GSK (LSE/NYSE:GSK) said that the PERLA Phase 2 study of dostarlimab met its endpoint of objective response rate in non-small cell lung cancer patients.

The study used Response Evaluation Criteria in Solid Tumors (RECIST) criteria to compare dostarlimab against Merck’s Keytruda (pembrolizumab) in patients with metastatic non-squamous non-small cell lung cancer who also received chemotherapy. A blinded independent central review evaluated the study’s results with RECIST v1.1 criteria.

AnaptysBio (Nasdaq:ANAB), a clinical-stage biotech, originally developed dostarlimab, which it later licensed to Tesaro, which GSK acquired in early 2019.

The randomized, double-blind PERLA study enrolled 243 patients.

GSK notes that the trial is the most extensive global head-to-head study of programmed death receptor-1 (PD-1) inhibitors in patients with metastatic non-squamous non-small cell lung cancer.

The company stresses that the study was not designed to show superiority.

GSK shares were down 0.68%, hitting $30.52 in early afternoon trading.

In the PERLA study, the most common adverse events in dostarlimab recipients were anemia, asthenia, nausea, constipation, cough, dyspnoea, vomiting, reduced appetite and neutropenia.

Dostarlimab first won FDA approval for women with recurrent or advanced mismatch repair-deficient (dMMR) endometrial cancer on April 22, 2021. On August 17, 2021, GSK won approval to use the drug in adults with dMMR recurrent or advanced solid tumors.

GSK plans to move both arms of its COSTAR NSCL cancer study into Phase 3.

The COSTAR lung trial is a Phase 2/3 study enrolling 750 patients.

In Phase 3, the study will continue to investigate dostarlimab in combination with the TIM-3 inhibitor cobolimab and docetaxel chemotherapy. It will also explore the use of dostarlimab and docetaxel, and docetaxel alone.

COSTAR will focus on patients who have progressed on prior anti-programmed death-ligand 1 therapy and chemotherapy.

“These trials support the ambition for dostarlimab to become the backbone of our ongoing immuno-oncology-based research and development program when used alone and in combination with standard of care and future novel cancer therapies, particularly in patients with currently limited treatment options,” said Hesham Abdullah, senior vice president, global head of oncology development at GSK, in a statement.