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

IntroductionTrastuzumab 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.MethodsThis 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.ResultsA 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).ConclusionsTrastuzumab reloading doses can be safely administered as a 30-min infusion, without increased risk of IRR or cardiotoxicity.