Kazia Therapeutics Limited (NASDAQ: KZIA) an oncology-focused drug development company, is pleased to announce the regulatory approval and launch of a clinical trial evaluating the combination of paxalisib and immunotherapy in patients with advanced breast cancer. This novel treatment combination offers what is believed to be a unique approach to targeting this highly aggressive and treatment-resistant type of breast cancer.

The ABC-Pax (Advanced Breast Cancer – Paxalisib) study is the first known trial conducted to assess the safety and efficacy of paxalisib in combination with KEYTRUDA^® (pembrolizumab) or LYNPARZA^® (olaparib) in women with triple negative breast cancer. ABC-Pax is a multi-centre, open-label phase 1b study that will enroll 24 patients from top cancer centres in Queensland, Australia and patients will receive the combination therapy for up to 12 months.

The ABC-Pax study stems from pivotal research led by QIMR Berghofer scientists in collaboration with Kazia Therapeutics, which combined its drug candidate, paxalisib, with immunotherapy in pre-clinical models. The team discovered that this combination approach triggers a novel molecular program by epigenetic re-programming of dormant cancer cells, making them visible to the immune system, while also reinvigorating the immune cells to fight the tumour cells. These new preclinical data were presented at San Antonio Breast Cancer Symposium on December 12, 2024, and highlight the potential therapeutic synergies between paxalisib and checkpoint inhibitor pembrolizumab (KEYTRUDA®), as well as 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. The clinical trial is open for enrollment at the Royal Brisbane and Women's Hospital and plans to expand to other sites in Australia.

Kazia Therapeutics CEO, Dr John Friend, said the novel combination treatment may have the potential to transform the treatment of triple-negative breast cancer and other aggressive tumour types.

"The novelty of the science that Professor Rao has proposed with this dual combination of paxalisib and immunotherapy could advance the treatment of women with aggressive breast cancer, and we are excited to support this unique clinical study," Dr John Friend, CEO Kazia Therapeutics said.

QIMR Berghofer's Professor Sudha Rao said, "There is no cure for triple negative breast cancer and the life expectancy for these women is tragically short. We want to identify treatments to extend the duration and quality of life of these patients. The hope is to prolong patient survival through the new combined therapy, which targets the dormant cancer cells that drive the spread and recurrence of the disease and rejuvenates the immune system to more effectively fight the cancer."

The ABC-Pax trial will also evaluate a non-invasive liquid biopsy digital pathology platform developed by Professor Rao and her team, which can monitor the behaviour of cancer cells and immune cells in real time from a blood sample.

"By regularly analysing blood samples from trial participants using our liquid biopsy digital pathology platform, we can track the effectiveness of the treatment in real time. We believe this approach represents a major advance in precision medicine by offering a faster and more accurate way to monitor patient progress," Professor Rao said.