Otsuka (TYO:4578) subsidiary Taiho Pharmaceutical, its unit Taiho Oncology, and Cullinan Therapeutics' lung cancer drug zipalertinib, in addition to platinum-based chemotherapy, showed a six-month median progression-free survival (PFS) benefit in a phase three Rezilient3 trial.

The results were "statistically significant and clinically meaningful," according to a Tokyo bourse filing on Monday.

The combination was tested as first-line treatment for advanced non-small cell lung cancer patients with epidermal growth factor receptor exon 20 insertion mutations.

At an interim analysis, the trial achieved a hazard ratio for death of 0.72, with follow-up ongoing.

The company first reported that the combination met its primary endpoint of PFS in August.

Shares of Otsuka Holdings fell nearly 1% in recent trade.