In France, over the past few years, the number of patients treated with chemotherapy (conventional and/or with targeted therapy) has steadily increased with a large proportion of patients treated for breast cancer (around 40%), and a constant paramedical staff in day care unit (DCU). Of the time spent in DCU, the waiting time is estimated at 50 minutes. Reducing waiting times, if not eliminating them, seems necessary since it is this unproductive time that generates the most dissatisfaction. One way to reduce the waiting time is to reduce the infusion time for chemotherapy. A new schedule of preparation and administration of trastuzumab and pertuzumab in the same infusion bag has been used in our health-care establishment for maintenance doses only (from cycle 2) that represents approximately 800 preparations per year. The administration time of the bag combining trastuzumab and pertuzumab is 30 minutes instead of 60 minutes when the products are administered separately. The time required to complete each step has been estimated from the computerized pharmaceutical validation process in the Centralized Cytotoxic Reconstitution Unit to the disconnection carried out by the nurse in DCU. Co-administration of these products reduces the average total wait time of patients at DCU by 40 minutes. This timesaving is significant and essential for the satisfaction of patients treated in DCU. The financial benefit linked to a saving in consumables is minimal, of the order of € 4.1 per preparation, or a saving of € 3,280 per year.