ANZadapt

Cancer constantly evolves. This evolution may even be accelerated by treatments such as radiation, chemotherapy, targeted or hormonal therapy. One therapeutic strategy to mitigate this evolutionary change is called 'adaptive therapy'. Adaptive therapy can be considered when using an effective but non-curative treatment. Treatment is used sparingly, for just long enough to control the cancer and maintain quality of life, but paused as soon as control is achieved. 'Adapting' the treatment to each patient aims to increase the duration of benefit, by using treatment-sensitive cancer cells to compete with, and control, treatment-resistant cancer cells. By changing the goal of therapy from "achieve the deepest/quickest short-term biochemical/radiological response" to "delay inevitable treatment resistance" we hope to prolong each patient's life and quality-of-life as much as possible. Mathematical models suggest substantial benefits may be possible. In a pilot clinical trial of adaptive abiraterone in castrate-resistant prostate cancer in the US, patient survival almost doubled [3] compared to contemporaneous and historical controls (time to progression 33.5 months vs 14.3 months in a contemporaneous cohort and ~11 months in COU-AA-302; median overall survival 58.5 months versus 31.3 months in a contemporaneous cohort and 34.7 months in COU-AA-302). These provocative findings must be tested in a prospective randomised clinical trial. We hope that the ANZadapt trial will provide the evidence to change practice and improve survival in men with metastatic castration-resistant prostate cancer.