Poster Session C
Myopathic rheumatic diseases (polymyositis, dermatomyositis, inclusion body myositis)
Saadia Sasha Ali, MSc, MBChB (she/her/hers)
King's College Hospital
Epsom, United Kingdom
No financial relationships with ineligible companies to disclose
92 patients received cyclophosphamide for IIM-ILD. 53 (57.6%) patients received the HD regime vs 39 (42.3%) in the LD arm. The mean age was 53 (13). 61 (66.3%) patients were female. Anti-Jo-1 antibody was positive in 41.5% in the high dose group vs 25.6% in the low dose group (Table 1). All-cause mortality was 11% in the HD arm vs 21% in the LD arm (p=0.23). Change in FVC (L) from baseline to 18 months is presented in figure 1. At 18 months, the change from baseline was greater in the HD arm [median 0.5 (IQR:-0.1-1.1) vs 0.1 (-0.0-0.4) (p=0.048)]. Change in TLCO at 18 months was numerically higher in the HD arm, but did not reach statistically significant [0.4 (-0.1-1.9) vs -0.2 (-0.6-0.6) (p=0.24)]. 9.4% in the HD arm had a serious infection vs 26.3% in the LD arm (p=0.032). Lymphopenia was higher in the HD arm vs LD arm (43.4% vs 25.6%, p=0.079) (Table 2). Overall, Patients in the LD arm had a longer duration of ILD, more NSIP, less OP, more frequent Mycophenolate Mofetil use, more pulmonary hypertension, less frequent concomitant Rituximab and a significantly higher CK at baseline, (suggesting more severe/systemic disease).
Conclusion:
HD cyclophosphamide was associated with a significant improvement in FVC vs LD cyclophosphamide at 18 months. All-cause mortality numerically favoured high dose cyclophosphamide and there were significantly fewer serious infections in the HD arm. Imbalances between the groups, in terms of severity of disease, may account for these observed differences. This study serves as an initial exploratory analysis for the use of low dose cyclophosphamide regimes in IIM-ILD but larger randomised trials would be needed to assess the efficacy and safety of this regime.
Fig 1. Change in FVC, by treatment regime FVC (L)
S. Ali: None; A. Lawrence: None; K. Bechman: UCB, viforpharma, 6; A. Patel: None; S. biring: None; S. Steer: None; A. Mahto: None; C. Myall: None; L. Pollard: None; M. Naqvi: None; A. Holloway: None; R. Salerno: None; F. Dell'accio: None; S. Agarwal: None; B. Lams: None; A. West: None; P. Gordon: Alexion, 12, Primary investigator at King's college hospital for the NCT04999020 study (ALXN1210-DM-310). No personal payment, Argenx, 12, PI at King's College Hospital for study ARGX-113-2007 and Study ARGX-113-2011, Bristol-Myers Squibb(BMS), 12, POETYK SLE study (NCT05620407), Chief investigator for UK and site PI at King's College Hospital London for this study ., Celltrion Healthcare, 12, Funded to attend EULAR convergence in 2023, Eli Lilly, 12, PI at King's College Hospital for MOJAK, funded by Eli Lilly with University of Manchester as the Sponsor. Termination date aproximate, Galapagos, 1, 2, 12, Chief investigator in UK for Galarisso study (NCT05695950).