Erasca has dosed the first patient in the Phase Ib SEACRAFT-1 trial of pan-RAF inhibitor naporafenib along with MEK inhibitor trametinib (MEKINIST) to treat RAS Q61X solid tumours.

The open-label study intends to assess the tolerability, safety, and preliminary efficacy of the combined therapy in previously treated patients with locally advanced unresectable or metastatic RAS Q61X solid tumour malignancies with NRAS, HRAS, and KRAS mutations.

Erasca chairman, CEO, and co-founder Jonathan Lim said: “Naporafenib has been dosed in over 500 patients to date, establishing its safety, tolerability, and preliminary proof-of-concept (PoC) in multiple indications.

“SEACRAFT-1 will explore the potential of naporafenib plus trametinib in patients with RAS Q61X solid tumours, which affects over 150,000 patients in the US and Europe.

“This tissue agnostic approach is based on the encouraging anti-tumour activity generated by Novartis in patients with NRAS Q61X melanoma or KRAS Q61X non-small cell lung cancer (NSCLC).”

The signal-seeking efficacy data of the study is anticipated between the second and fourth quarters of next year.

Erasca is also planning to start the pivotal Phase III SEACRAFT-2 trial to assess naporafenib and trametinib in NRAS-mutant melanoma patients, in the first half of next year.

It is also exploring naporafenib’s additional combinations with other therapeutic agents.

Last October, Erasca and Pfizer entered an agreement to conduct a clinical PoC trial of ERAS-007 plus palbociclib to treat KRAS- and NRAS-mutant colorectal cancer and KRAS-mutant pancreatic ductal adenocarcinoma.

Erasca sponsored the trial while Pfizer supplied palbociclib for free of charge.