Abstract : <p>Women with advanced breast cancer (ABC) who are hormone receptor (HR) positive and human epidermal growth factor receptor 2 (HER 2) negative are candidates for first line hormonal therapy including aromatase inhibitors (AI). In the past few years new combination therapies became available as  palbociclib with letrozole; increasing the progression free survival (PFS)<strong> </strong>[1]<strong>.</strong> Several studies were conducted to assess the chemo-endocrine combination in ABC<strong> </strong>among which some assessed the combination of capecitabine with aromatase inhibitors [2].Our study is a prospective phase II trial; we randomly assigned patients with HR positive, Her 2 negative ABC, who didn’t receive previous systemic endocrinal treatment for ABC to receive aromatase inhibitor (AI) or capecitabine (625 mg/m2 bid PO for 14 days; repeated every 21 days)  plus AI administered daily  (CapAI).We carried out an interim analysis to determine the toxicity of the CapAI combination. Toxicity was assessed in both arms. There was no significant difference in the rates of toxicity in both arms regarding haematological toxicity (anaemia, thrombocytopenia and neutropenia), fatigue, nausea, vomiting, diarrhoea, mucositis. But there was significant difference in the hand foot syndrome with the 14.8% in the CapAI arm versus 0 % in the AI only arm, peripheral neuropathy with 25.9 % vs 2.3% and hepatic toxicity 14.8% vs 0 %. Grade 3 toxicity was reported in only 3 patients in our study all in the CapAI arm (fatigue, thrombocytopenia and neutropenia). No permanent discontinuation occurred but 25% dose reduction was done in one patient due to decrease in creatinine clearance.</p>