Real-World Treatment Patterns and Clinical Outcomes Among Patients With Triple-Class-Exposed and BCMA-Exposed Multiple Myeloma Within the United States

Abstract

Introduction: A novel therapy for heavily pretreated triple-class-exposed multiple myeloma (TCE MM) is B-cell maturation antigen (BCMA)-targeted immunotherapy. While the number of TCE+BCMA-exposed patients is growing, real-world data for this group are limited.

Methods: We present real-world data from patients with TCE+BCMA-exposed MM who initiated a subsequent line of therapy (LOT) using a US-based claims database, Komodo's Healthcare Map.

Results: We identified 656 TCE+BCMA-exposed patients; mean age was 66.5 years. Time from MM diagnosis to index was 5.4 years; mean number of prior LOTs was 5.9. The most prevalent prior therapy received within each drug class was daratumumab (98.5%), pomalidomide (86.0%), carfilzomib (85.8%) and belantamab mafodotin (74.5%). A total of 137 different subsequent treatment regimens were observed following TCE+BCMA exposure; the most common regimen was teclistamab (10.4%). The top three targeted agents within the subsequent regimen were carfilzomib (20.2%), pomalidomide (20.1%) and bortezomib (16.6%). Among this TCE+BCMA-exposed population who received subsequent treatment, the median time to next treatment or death was 6.8 (95% CI, 6.1-7.5) months; time to treatment discontinuation or death was 3.5 (95% CI, 3.2-3.7) months.

Conclusion: This first real-world analysis of patients with heavily pretreated TCE+BCMA-exposed MM shows poor clinical outcomes, frequent therapy retreatment and no standard-of-care, highlighting the need for novel treatments.

Clinical trial registration: The authors have confirmed clinical trial registration is not needed for this submission.

Keywords: BCMA; clinical outcomes; multiple myeloma; real‐world; triple‐class–exposed.

FIGURE 1

Study design for patients with TCE+BCMA‐exposed MM. BCMA, B‐cell maturation antigen; CAR‐T, chimeric antigen receptor T‐cell; LOT, line of therapy; MM, multiple myeloma; TCE, triple‐class–exposed; TTD, time to discontinuation; TTNT, time to next treatment. ^aIndex date was defined as the start date of the subsequent LOT following TCE+BCMA exposure (or CAR‐T infusion date for CAR‐T‐containing LOTs). ^bThe follow‐up period was defined as the time from the index date to the last claim date, death or the end of the study period, whichever was earlier.

FIGURE 2

Summary of attrition and cohort selection for patients with MM with prior TCE+BCMA exposure and ≥ 4 prior LOTs. BCMA, B‐cell maturation antigen; HCPCS, Healthcare Common Procedure Coding System; ICD‐9‐CM, International Classification of Diseases, Ninth Revision, Clinical Modification; ICD‐10‐CM, International Classification of Diseases, Tenth Revision, Clinical Modification; IMiD, immunomodulatory drug; LOT, line of therapy; mAb, monoclonal antibody; MM, multiple myeloma; PI, proteasome inhibitor; TCE, triple‐class–exposed. ^aRetention percentages are calculated from the total number of patients from the previous step. ^bTCE was defined as ≥ 1 PI, ≥ 1 IMiD and ≥ 1 anti‐CD38 mAb between the study start date and intake end date. ^cCodes used for clinical trials were as follows: ICD‐9‐CM: V70.7; ICD‐10‐CM: Z00.6; HCPCS: S9988, S9990, S9991, S9992, S9994, S9996; HCPCS modifier: Q0, Q1.

FIGURE 3

TTNT and TTD in patients with MM with prior TCE+BCMA exposure and ≥ 4 prior LOTs. BCMA, B‐cell maturation antigen; CI, confidence interval; LOT, line of therapy; MM, multiple myeloma; TCE, triple‐class–exposed; TTD, time to discontinuation; TTNT, time to next treatment. ^aTTNT was defined as the time from the index date to death or the initiation of a next LOT. ^bTTD was defined as the time from the index date to death or the discontinuation of the index LOT. ^cDue to Komodo Health's patient deidentification policies, data including 1–10 patients were masked.