(003) Survival and drug treatment patterns in multiple myeloma patients exposed to an anti-CD38 monoclonal antibody, a proteasome inhibitor and an immunomodulatory imide drugs

Publication Number: 667

Background: Advancements in the field of multiple myeloma (MM) treatment, including new drug regimens, have led to improvement in patient survival. However, there is a scarcity of real-world data regarding treatment outcomes for triple-class exposed MM patients, meaning they have been treated with an immunomodulatory imide drug (IMiD), a proteasome inhibitor (PI) and an anti-CD38 monoclonal antibody (mAb).

Objectives: To gain a deeper understanding of subsequent drug regimens used to treat triple-class exposed MM patients, including the interval until the subsequent treatment and the associated survival rate.

Methods: Data for this cohort study was obtained from the PHARMO Data Network. MM patients who were triple-class exposed, were included when they received a next treatment line during follow-up. Dates of initiation of subsequent new treatment lines were defined as index dates. First endpoint was ‘overall survival’ (OS) which was the time from index date to death, end of data availability or December 31, 2020. Second endpoint was ‘time-to-next-treatment’ (TTNT) which was time to start of next treatment line. Descriptive statistics were provided for patient characteristics and medication used in each new treatment line.

Results: Out of 65 triple-class exposed MM patients who received subsequent a line of treatment, 29% were given two additional and 6% three additional lines of treatment. In the first subsequent line of treatment, 23 different treatment combinations were used. At the start of this line of treatment, patients were 69 years old on average and 45% was female. The type of hospital where the new treatment was initiated was equally distributed among peripheral (32%), larger regional (28%), and academic (31%) hospitals. In the second subsequent line of treatment, 12 different treatment combinations were used. For patients receiving a second subsequent line of treatment, the average age was 69 years, 53% was female and this treatment was more often initiated in academic hospitals (53% vs. 21% for other types). The median TTNT for the first subsequent treatment line was 127 days (interquartile range (IQR): 79-200). The OS after the first subsequent treatment line was 217 days (IQR: 89-304). The most common first subsequent treatment line was combination therapy of carfilzomib and dexamethasone (17%). For the line of treatment thereafter, this was cyclophosphamide with pomalidomide (21%).

Conclusions: We did not observe a standard of care for triple-class exposed MM patients. As the treatments given were very heterogeneous, despite improvements in patient and clinical outcomes, current treatment strategies have a limited survival benefit. Hence, a novel treatment approach is needed for MM patients.