Earlier use for abiraterone
Abiraterone (Zytiga) has been approved to treat newly-diagnosed high-risk metastatic hormone-sensitive prostate cancer in combination with androgen deprivation therapy (ADT). The drug was previously licenced for metastatic castration resistant prostate cancer in adults who are asymptomatic or mildly symptomatic after failure of ADT in whom chemotherapy is not yet clinically indicated and in adult men whose disease has progressed on or after a docetaxel-based chemotherapy regimen.
The approvals follows positive results from the multinational, multicentre, randomised, double-blind, placebo-controlled phase 3 study LATITUDE showing a 38% reduction in the risk of death with abiraterone plus ADT compared to placebo plus ADT (HR=0.621; 95% CI: 0.509, 0.756; p<0.0001). Abiraterone was also associated with a 53% lower risk of disease progression and delayed progression by a median of 18.2 months.
In the trial, a high-risk prognosis was defined as having at least two of the following three risk factors: Gleason score of ≥8; presence of three or more lesions on bone scan; presence of measurable visceral (excluding lymph node disease) metastasis.