China-based BeiGene's RAF dimer inhibitor, lifirafenib, is being assessed in combination with SpringWorks Therapeutics' investigational MEK inhibitor, PD-0325901, in a phase 1b clinical trial in patients with advanced solid tumours, it was reported Friday.

The companies have signed a global clinical collaboration contract to evaluate the safety, tolerability and preliminary efficacy of this combination. BeiGene will have responsibility for administering the early-stage trial, which is expected to start during the first quarter of 2019.

BeiGene stated that the inhibitor showcased antitumor activities in preclinical models and in cancer patients with tumours harbouring BRAF V600E mutations, non-V600E BRAF mutations and also non-small cell lung cancer and endometrial cancer harbouring KRAS mutations. PD-0325901, which inhibits MEK, has been demonstrated in clinical biopsies to block MEK phosphorylation, leading to cell death.