Loncastuximab tesirine in previously treated diffuse large B-cell lymphoma: A plain language summary of the LOTIS-2 study.

What is this summary about?: This article provides a plain-language summary of the results of a clinical trial called the LOTIS-2 study.The LOTIS-2 study included 145 participants with an aggressive type (one that forms, grows, or spreads quickly) of non-Hodgkin lymphoma called diffuse large B-cell lymphoma (a type of blood cancer), or DLBCL for short, whose disease came back or did not respond after 2 or more previous treatments. The LOTIS-2 study was conducted from August 2018 to September 2022.Participants received loncastuximab tesirine, also referred to as Lonca, for up to 1 year, or longer if the treatment was working, and their health was monitored. The primary purpose of the LOTIS-2 study was to find out if participants' lymphoma shrank partially or completely after receiving Lonca.

What were the results?: A total of 145 participants who were treated with Lonca lived a median (meaning the middle value in a set of numbers) of 9.5 months after starting Lonca treatment. The lymphoma shrank partially or completely in nearly half of participants and shrank completely in 1 in 4 participants. Among participants whose disease either shrank partially or completely in response to Lonca treatment, responses happened relatively quickly, with a median time to response (the time between starting treatment and when the participant's lymphoma either partially or completely shrank) of 41 days. In these participants, the lymphoma did not grow or come back for a median of 13.4 months. Researchers estimated that 83% of participants whose disease shrank completely remained disease free for at least 1 year.Nearly all participants had a side effect from Lonca treatment. The most common side effects were abnormal liver tests (increased gamma-glutamyl transferase), decreased white blood cells (neutropenia), and decreased platelets (thrombocytopenia). One in 4 participants had their treatment stopped due to side effects. The most common side effects that resulted in participants needing to stop Lonca treatment were abnormal liver tests (increased gamma-glutamyl transferase), swelling in the arms or legs (peripheral edema), swelling in an individual spot (localized edema), and fluid around the lungs (pleural effusion).

What do the results of the study mean?: These results show that Lonca is a treatment option with controllable side effects for many patients with DLBCL whose disease did not respond or came back after 2 or more previous treatments. For participants whose lymphoma completely shrank while taking Lonca, those responses to treatment occurred quickly and lasted for over a year.