Oncology-focused drug development company Kazia Therapeutics Limited (NASDAQ: KZIA) announced on Thursday the regulatory approval and launch of a clinical trial assessing the combination of paxalisib and immunotherapy in patients with advanced breast cancer.

This treatment combination provides a unique approach to target highly aggressive and treatment-resistant type of breast cancer, Kazia Therapeutics said.

ABC-Pax (Advanced Breast Cancer – Paxalisib) is the first known trial carried out to evaluate the safety and efficacy of the product along with KEYTRUDA (pembrolizumab) or LYNPARZA (olaparib) in women with triple negative breast cancer. The multi-centre, open-label phase 1b study will enrol 24 patients from top cancer centres in Queensland, Australia. Patients will receive the combination therapy for up to 12 months.

The ABC-Pax study stems from pivotal research headed by QIMR Berghofer scientists in partnership with Kazia Therapeutics that combined its drug candidate, paxalisib, with immunotherapy in pre-clinical models. Findings indicate the potential therapeutic synergies between paxalisib and checkpoint inhibitor pembrolizumab (KEYTRUDA), and between paxalisib and poly (ADP-ribose) polymerase inhibitor olaparib (LYNPARZA), when used in combination in a preclinical model of immunotherapy-resistant triple negative breast cancer.

Enrolment in the clinical trial has begun at the Royal Brisbane and Women's Hospital and is planned to expand to other sites in Australia.