Reducing Symptom Burden in Older Patients with Multiple Myeloma (MM) Using Interleukin-6 (IL-6) Blockage Peri-Autologous Hematopoietic Stem Cell Transplantation (AHCT)

Background For MM patients (pts), AHCT improves progression free and overall survival, but in older pts is often associated with significant symptom burden. IL-6 levels peak during count nadir when symptom burden also peaks. We aimed to improve symptom burden using siltuximab (anti-IL-6 antibody, Janssen) peri-AHCT. Methods Siltuximab was given at 11 mg/kg on day -7 and day +21 from AHCT. MD Anderson Symptom Inventory – MM was measured at baseline, day -2, +7, and +30. IL-6 and C-reactive protein (CRP) were measured at baseline, day -2, 0, +3, +7, +14, +21, and +30. Results Between 1/2018 – 8/2018, 14 pts (median age 65 (range 60-70), 7 female) were enrolled. One pt was removed from study after the day -7 siltuximab due to primary physician request as AHCT was delayed due to frailty and non-compliance. Results below are based on remaining 13 pts. Median HCT-CI was 1 (range 0-8, with 5 pts’ HCT-CI >2) and median KPS on day -2 was 80 (range 70-90). Two pts had mild infusion reactions, one with tingling of lips and one with hives which resolved with Benadryl. Neither had a reaction with the subsequent infusion. Neutrophil engraftment occurred at a median of 9 days (range 8-11), but 5 pts (38%) received at least one dose of filgrastim after engraftment. No pts had neutropenic fevers, but one pt developed a pneumonia requiring high-flow oxygen. Two pts (15%) had engraftment syndrome. CRP levels were elevated at baseline in 85% of pts with median level of 0.12 mg/dL (range Conclusion Siltuximab appears to decrease fatigue without delaying engraftment, but may delay full count recovery. No pts developed a neutropenic fever. Full interim analysis of MDASI-MM, IL-6, and CRP trends will be presented.