This is an open-label phase II study of systems biology guided therapy for breast cancer patients positive for Oestrogen receptor after Aromatase inhibitor and CDK inhibition.
Based on the SOLAR-1 trial, 25% of tumors would have PIK3CA mutation, so 25% of people would be treated with fulvestrant plus alpelisib with a median PFS in that group of 11 months and 75% of people would be treated with fulvestrant with a median PFS in that group of 6 months.(3) The weighted average of these medians is 7.25 months, but since the actual distributions of the progression free survivals are not available, we will use a conservative estimate of the expected median PFS of the historical control group (fulvestrant +/- alpelisib as second line unguided therapy) of 8 months.
