Plain language summary of the ECHELON-3 study: brentuximab vedotin combination treatment in people with diffuse large B-cell lymphoma

What is this summary about? This is a summary of the results of a study called ECHELON-3. This study compared a brentuximab vedotin (BV) combination (BV, lenalidomide, and rituximab) and a placebo combination (placebo, lenalidomide, and rituximab). This analysis looked at how well the medicines worked and their side effects in people with a type of cancer called diffuse large B-cell lymphoma (DLBCL) that had relapsed or was refractory after previous treatments. The ECHELON-3 study is ongoing, and the results summarized here are not final. What were the results? In this study, 230 people with relapsed or refractory DLBCL were randomly assigned to receive either the BV combination (112 people) or the placebo combination (118 people). How long did they live? At least half of the people who received the BV combination lived for 13.8 months compared with 8.5 months for people who received the placebo combination. This benefit was seen in different subgroups of people, including people at high risk and people who had tried other advanced treatments. Did their tumors shrink or become undetectable on scans? More people who received the BV combination (72 out of 112, or 64%) had their cancer shrink or become undetectable (was not visible) on scans than people who received the placebo combination (49 out of 118, or 42%). Cancer became undetectable on scans for 45 out of 112 people (40%) who received the BV combination and 22 out of 118 people (19%) who received the placebo combination. Did they have any side effects from the medicines? Most people who received either the BV combination (109 out of 112, or 97%) or the placebo combination (113 out of 116, or 97%) experienced side effects. However, most side effects in the study were manageable. What do the results mean? This study showed that compared with people who took the placebo combination, people who took the BV combination lived longer; more people who took the BV combination had their cancer shrink or become undetectable on scans. For both treatments, side effects were similar and generally manageable.