United States-based Adastra Pharmaceuticals Inc has completed the Phase 1b clinical trial conducted by the National Cancer Institute (NCI) with its lead clinical candidate zotiraciclib (ZTR/TG02), a potent oral cyclin-dependent kinase 9 (CDK9) inhibitor, it was reported on Wednesday.

The trial assessed the safety and efficacy of the product in combination with temozolomide in subjects with recurrent high-grade gliomas. It exceeded or met the prespecified trial endpoint of progression-free survival and provided a recommended dosing for ZTR. It was sponsored and conducted by the NCI.

Jing Wu, MD, PhD, NCI's principal investigator for the 17-C-0009 trial, said, 'Because preclinical data demonstrated the ability of ZTR to inhibit CDK9, enhance apoptosis and cause mitochondrial dysfunction and ultimately ATP depletion in glioma cells, we were optimistic about this first-in-human glioma trial. The data from the Phase 1b trial support our initial expectations and reinforce our energies to continue to investigate ZTR as a treatment for patients with gliomas.'