Paxalisib

Sept. 1, 2026: Kazia Therapeutics (NASDAQ: KZIA) reported preclinical/translational data for paxalisib in microsatellite stable/proficient mismatch repair (MSS/pMMR) colorectal cancer. In a preclinical model, paxalisib monotherapy reduced tumor burden by 52% (p=0.035). In a separate study, adding paxalisib to pembrolizumab reduced tumor volume by an additional 50% versus immunotherapy alone (p=0.022). The company said treatment was well tolerated in both studies, with no treatment-related toxicity observed.

Kazia also said it is advancing a translational biomarker program to identify molecular, immune, and epigenetic signatures linked to paxalisib response, and has made a new patent filing related to potential colorectal cancer use.

The company plans a five-arm Phase 2 trial in pre-treated MSS/pMMR metastatic colorectal cancer evaluating paxalisib monotherapy and paxalisib plus pembrolizumab, with or without biologic, at 15 mg and 30 mg doses, versus standard of care. The primary endpoint is safety/tolerability; secondary endpoints are progression-free survival, overall response rate, and overall survival. Enrollment is expected to begin in Q1 2027, with full enrollment across all five arms anticipated by the end of 2027.