If Astellas needed further proof its $1.3 billion oncology bet was worth the price tag, the second successful phase 3 trial in a month should do the trick.
Zolbetuximab, an anti-CLDN18.2 antibody, was secured as part of Astellas’ acquisition of Ganymed Pharmaceuticals back in 2016. That investment appeared to pay off last month in the form of the phase 3 SPOTLIGHT trial, which showed zolbetuximab alongside chemotherapy improved progression-free survival in patients with CLDN18.2-positive, HER2-negative locally advanced unresectable or metastatic gastric or gastroesophageal junction cancer.
Now, the 507-participant GLOW trial has produced more positive results for a similar patient population. The study met its primary endpoint of showing statistical significance in progression-free survival for patients treated with zolbetuximab plus the chemotherapy CAPOX compared to placebo plus CAPOX.
The trial also demonstrated statistical significance in overall survival for the zolbetuximab-CAPOX regimen. The most frequent treatment-emergent adverse events were nausea and vomiting, Astellas noted.
With a total of more than 1,000 patients having participated across the GLOW and SPOTLIGHT studies, Astellas said it has the foundational data needed to submit zolbetuximab for approval in the U.S., Europe and globally. It also cements Astellas’ status as the front-runner in the CLDN18.2 space, giving the Japanese drugmaker a clear run at a target that was expressed by 38% of the patients screened in the two late-stage trials.
"This further confirms the potential role of zolbetuximab in gastric cancer treatment, an important milestone in our gastric cancer development program," said Astellas’ head of development for therapeutic areas, Ahsan Arozullah, M.D., in a postmarket release Thursday. "We intend to discuss these results with regulatory authorities as we continue to develop zolbetuximab for the first-line treatment of patients with locally advanced unresectable or metastatic gastric and GEJ cancer."
While Astellas is head of the pack, the CLDN18.2 pipeline suggests competitors with different spins on how to hit the target are coming, with companies including BioNTech and Legend Biotech trialing mRNA, CAR-Ts and other modalities.