Feasibility and safety of 30-minute Trastuzumab reloading infusion in patients with HER2-positive solid tumors

Introduction Trastuzumab is a humanized HER2 targeting monoclonal antibody, and it is indicated for the treatment of various HER-2-positive cancers, including breast and gastrointestinal cancers. The standard protocol involves a 90-min intravenous loading dose, followed by 30-min maintenance infusions. If a maintenance dose is missed by more than a week, the prescribing information recommends a 90-min reloading infusion of 8 mg/kg, regardless of prior tolerance and duration of maintenance therapies. This study aims to assess the safety of 30-min reloading infusions which has not been previously studied. Methods This was a single-center, retrospective cohort study that compared the safety of trastuzumab reloading 8 mg/kg as 30 min infusion and 90 min infusion in adults with HER2-positive cancers at a comprehensive cancer center. The primary endpoint was the incidence of infusion-related reactions (IRRs). Secondary endpoints included IRR severity, number of symptoms, time to reaction, rate of decrease in left ventricular ejection fraction (LVEF), and IRR risk factor identification. Results A total of 169 patients were included (90-min = 123; 30-min = 46). Our findings demonstrated that the shorter 30 min infusion is as safe as 90 min infusion. The IRR rate was 0% in 30 min vs. 4% in 90 min. Additionally, the mean percentage of LVEF reduction was similar between the two cohorts (4.1% in 30 min vs. 3.97% in 90 min; P = 0.99). Conclusions Trastuzumab reloading doses can be safely administered as a 30-min infusion, without increased risk of IRR or cardiotoxicity.