P1717: HEALTH-RELATED QUALITY OF LIFE AND TOLERABILITY OF LONCASTUXIMAB TESIRINE IN HIGH-RISK PATIENTS WITH RELAPSED/REFRACTORY DIFFUSE LARGE B-CELL LYMPHOMA TREATED IN A PHASE 2 CLINICAL TRIAL (LOTIS 2)

Abstract

Background: Loncastuximab tesirine (loncastuximab tesirine-lpyl; Lonca) has shown antitumor activity with an acceptable toxicity profile and provides stable or improved health-related quality of life (HRQOL) in adult patients with relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL) after ≥ 2 prior therapies. Lonca has also shown promising results for patients who are at high risk of a poor prognosis (i.e., with double/triple hit, primary refractory, or transformed disease). Aims: This analysis evaluates the impact of Lonca on HRQOL and patient tolerability to treatment stratified by high-risk group. Methods: The LOTIS 2 study (NCT03589469) is a single-arm, open-label, phase 2 study of adult patients with R/R DLBCL after ≥ 2 prior treatments. Patients received Lonca as an intravenous infusion on day 1 of each 3-week treatment cycle. The EuroQol EQ-5D visual analog scale (VAS) was used to measure overall health state, and the Functional Assessment of Cancer Treatment–Lymphoma (FACT-Lym) was used to measure HRQOL, including physical, social/family, emotional, and functional well-being, and lymphoma-specific symptoms and concerns. Mean change from baseline scores during the treatment period were summarized by visit and risk group. Analysis of covariance (ANCOVA) models were conducted to adjust for age, sex, race, and baseline score. Treatment tolerability was reported by patients in FACT-Lym item GP5 (“I am bothered by side effects of treatment”). This single item has been used to measure overall side effect impact on patients. All patients provided written informed consent to participate the study. Results: Patients with a baseline score and at least one postbaseline score were included in the analysis. Through cycle 9, the completion rate among patients treated at each cycle was ≥ 92% for EQ-5D and ≥ 88% for FACT-Lym. Of the 127 patients included in analysis, 16% were aged ≥ 75 years, 58% were male, 88% were White, and 39% were high risk. In the high-risk group, both unadjusted and adjusted analyses showed the VAS overall health score was improved after 2 cycles of treatment (figure and table); the FACT-Lym total score was also improved at some visits. In the non–high-risk group, the VAS and FACT-Lym total scores remained stable or improved except later cycles with small sample sizes. When asked how much they were bothered by treatment side effects, a majority of patients reported “a little bit” or “not at all” at most cycles (71%-89% in the high-risk group and 46%-86% in the non–high-risk group). Table. - Adjusted Mean Change From Baseline Scores of EQ-5D VAS and FACT-Lym Total Least Squares Means by Visit C2D1 C3D1 C4D1 C5D1 C6D1 C7D1 C8D1 C9D1 EQ-5D VAS High risk -0.6 6.8* 7.5** 5.8 0.3 8.7 13.0* 9.9 Non-high risk 0.1 2.1 3.3 1.5 2.5 1.6 7.7 8.5 Difference -0.7 4.7 4.2 4.4 -2.2 7.1 5.3 1.4 FACT-Lym total High risk -0.7 6.7 6.8 2.5 14.1** 24.5** 29.1** 20.6** Non-high risk 2.6 4.7 3.9 2 4.2 9.9 8.8 17.9** Difference -3.3 2 2.9 0.6 9.9 14.6* 20.3** 2.7 * 0.05 < P < 0.10; ** P <0.05. Age, sex, race, and baseline score were adjusted in the ANCOVA model. Visits after C9D1 are not displayed due to small sample sizes. A change of 7 points for the EQ VAS or FACT-Lym total is considered a minimally important difference. A positive change indicates improvement. Image:Summary/Conclusion: The overall health state and HRQOL were stable or improved in high-risk patients during the treatment period of Lonca. Patients in the high-risk group tolerated the treatment just as well, if not better, as other patients. The findings further support the clinical use of Lonca for the treatment of R/R DLBCL in patients with high risk.