GSK's Jideytro & Ris-Rez Show Positive Data In Two Lung Cancer Studies

(RTTNews) - GSK plc (GSK), a biopharmaceutical company, reported positive clinical data for two of its lung cancer medicines, with Jideytro showing high response rates in previously untreated ROS1-positive non-small cell lung cancer (NSCLC), while Ris-Rez reduced the risk of death by 54% versus topotecan in patients with relapsed small cell lung cancer (SCLC).

Jideytro (zidesamtinib) is a next-generation, ROS1-selective tyrosine kinase inhibitor (TKI) designed to target ROS1 resistance mutations, including disease that has spread to the brain.

The drug is currently FDA-approved for adults with locally advanced or metastatic ROS1-positive NSCLC who have received a prior ROS1 TKI.

The first-line data came from the registrational Phase 1/2 ARROS-1 trial, a global, single-arm study evaluating Jideytro in patients with advanced ROS1-positive NSCLC and other ROS1-positive solid tumors.

A total of 532 patients with ROS1-positive NSCLC received zidesamtinib 100 mg once daily across all lines of therapy, out of which 183 were receiving their first TKI-targeted treatment. In the TKI-naive cohort, 94 patients with advanced or metastatic ROS1-positive NSCLC were evaluated for efficacy.

In the 94 TKI-naive cohort, after a median follow-up of 15.2 months, the objective response rate (ORR) was 94%, including a 15% complete response rate.

Ninety percent of patients remained progression-free (PFS) at 12 months, while median PFS and duration of response had not been reached.

Among 10 patients with measurable brain metastases, all responded to Jideytro, with 70% achieving complete clearance of detectable brain tumors.

At 12 months, 78% maintained an intracranial response, while no central nervous system progression events were observed among patients without brain metastases at baseline.

Treatment-related adverse events (AEs) were generally low grade, with peripheral edema, weight increase, increased blood creatine phosphokinase, dysgeusia, and increased aspartate aminotransferase were among the most common.

Treatment-related AEs led to dose reductions in 11% of patients and treatment discontinuation in 1%.

Jideytro is currently FDA-approved for adults with locally advanced or metastatic ROS1-positive NSCLC who have received a prior ROS1 TKI. GSK plans to submit a supplemental New Drug Application in 2026 seeking to expand the indication to first-line treatment.

Separately, GSK's licensor Hansoh Pharmaceutical Group reported positive Phase 3 results from the ARTEMIS-008 trial evaluating Ris-Rez (risvutatug rezetecan) against topotecan in China in patients with relapsed SCLC following first-line platinum-based therapy.

ARTEMIS-008 is a multicenter, randomized, open-label study in China, which enrolled 461 patients, with 230 receiving Ris-Rez 8.0 mg/kg every three weeks or topotecan 1.2 mg/m² on Days 1-5 of each 21-day cycle.

Overall survival (OS) was the primary endpoint, with progression-free survival (PFS), objective response rate (ORR), disease control rate, duration of response, and safety among the secondary endpoints.

In the Phase 3 study, Ris-Rez reduced the risk of death by 54% versus topotecan, meeting the primary OS endpoint after a median follow-up of 12.2 months. Median OS was 18.5 months with Ris-Rez versus 10.3 months with topotecan.

The survival benefit was supported by improvements in other efficacy measures. Median PFS assessed by an independent review committee (IRC) was 7.2 months versus 3.0 months, while ORR was 58.3% compared with 12.6%.

Additionally, IRC-assessed disease control rate was 90.4% in Ris-Rez versus 60.2% in topotecan, respectively.

Grade 3 or higher treatment-related adverse events occurred in 60.9% of patients receiving Ris-Rez while 78.2% who received topotecan.

The most common treatment-related events with Ris-Rez were decreased neutrophils, decreased white blood cells, anemia, decreased lymphocytes and decreased platelets. GSK holds exclusive rights to develop and commercialise Ris-Rez, an investigational B7-H3 antibody-drug conjugate (ADC) outside mainland China, Hong Kong, Macau and Taiwan.

The company is advancing the drug through its global EMBOLD development program, including the Phase 3 EMBOLD SCLC-301 trial in relapsed extensive-stage SCLC, with pivotal data expected next year.

GSK shares closed on Friday at $48.13, up 0.02%. In the pre-market trade, shares are up 3.79% at $49.95.