NEW YORK – AnHeart Therapeutics said on Tuesday that it has dosed the first ROS1 fusion-positive non-small cell lung cancer patient in a Phase II trial evaluating the investigational drug taletrectinib at Shanghai Pulmonary Hospital.
This Phase II open-label, single-arm trial aims to enroll approximately 106 NSCLC patients with ROS1 fusions. The study will have two cohorts, the first will contain patients who have never received tyrosine kinase inhibitor treatment, and the other will contain patients who have progressed on crizotinib (Pfizer's Xalkori). AnHeart said they expected to report topline results in Q4 of 2021.
Taletrectinib is a ROS1 and NTRK inhibitor that AnHeart licensed from Daiichi Sankyo. The drug inhibits both ROS1 wild-type and major crizotinib-resistant ROS1 mutations, including ROS1 G2032R. There are currently no approved drugs that are effective against ROS1 resistant mutations.
AnHeart stated that the results of two Phase I studies in the US and Japan support the potential of taletrectinib to be a next-generation ROS1/NTRK inhibitor because it produced durable responses in patients and had activity in those with brain metastases. Based on combined data from the two Phase I studies, at a cutoff date in March 2019, the median progression-free survival in tyrosine kinase inhibitor-naïve patients was 24.6 months, and in one patient who had prior TKI treatment, 18.4 months. In the US study, the overall response rate was 33.3 percent. Patients receiving the drug had manageable toxicities at the maximum tolerated daily dose of 800 mg.
AnHeart also plans to start a second Phase II trial this year involving approximately 40 patients with locally advanced or metastatic solid tumors harboring NTRK fusions. Further down the line, the company intends to launch global Phase II taletrectinib trials in the US, EU, Japan, Korea, and the rest of world for NSCLC patients with ROS1 fusions and solid tumors with NTRK fusions.