GSK showcases positive data with lung cancer drugs at WCLC

GSK reported good clinical trial results with two of its lung cancer therapies – Jideytro and risvutatug rezetecan (ris-rez) – at the ongoing WCLC congress in Seoul, South Korea.

First up, ROS1 inhibitor Jideytro (zidesamtinib) – GSK's first-ever lung cancer therapy – which was approved by the FDA as a second-line or later therapy for adults with locally advanced or metastatic ROS1-positive non-small cell lung cancer (NSCLC) in July and came from its $10.6 billion takeover of Nuvalent.

The new data comes from the phase 1/2 ARROS-1 study, which underpinned Jideytro's approval as a second-line therapy, but also included a cohort of previously untreated ROS1+ NSCLC patients.

Among this cohort of treatment-naïve subjects, Jideytro achieved an objective response rate of 94% at just over 15 months' follow-up, with nine out of 10 of them progression-free at 12 months. As a second-line therapy, the drug achieved an ORR of 44%, with 69% of patients still responding to the treatment after 12 months' follow-up.

The median progression-free survival (PFS) had not been reached by the data cutoff, according to Alexander Drilon of Memorial Sloan Kettering Cancer Center in the US, who presented the results at WCLC.

Moreover, Jideytro showed good efficacy in patients whose cancer had spread to the brain, with 70% of this group showing complete clearance of detectable brain tumours.

"Patients with ROS1-positive NSCLC may receive treatment for many years while continuing to work, care for their families, and live their daily lives," he said. "They need treatments that provide lasting control of their disease, including in the brain, while limiting side effects and treatment disruption."

GSK intends to file for approval of Jideytro as a first-line therapy for ROS1-positive NSCLC on the strength of the new data. The drug is one of three for lung cancer acquired with Nuvalent, alongside ALK inhibitor neladalkib – under review at the FDA for pre-treated, advanced-stage ALK-positive NSCLC, with a decision due in November – and NVL-330 for HER2-altered NSCLC.

Ris-rez shows its rizz

Meanwhile, GSK is developing another lung cancer candidate – B7-H3-targeted antibody-drug conjugate (ADC) ris-rez – and had encouraging news to report on that programme at WCLC.

Hansoh Pharma, which originated ris-rez and licensed it to GSK in a $1.7 billion deal in 2023, revealed new data from the Chinese ARTEMIS-008, which showed a statistically significant 54% improvement in OS with the ADC compared to topotecan chemotherapy when used as a second-line therapy for small cell lung cancer (SCLC).

Patients treated with ris-rez after the failure of platinum chemo lived a median of 18.5 months, versus 10.3 months with topotecan. It is the first phase 3 trial to show an OS benefit for a B7-H3 ADC in any tumour type, according to GSK, which has rights to the drug outside Greater China. The company is running the phase 3 EMBOLD SCLC-301 trial of the ADC in relapsed extensive-stage SCLC, with results expected in 2027.

Earlier this year, GSK also reported positive clinical results with another ADC licensed from Hansoh, the B7-H4-directed mocertatug rezetecan (mo-rez) in platinum-resistant ovarian cancer (PROC) and recurrent or advanced endometrial cancer.