PO139 Integrated safety analysis; cladribine in multiple sclerosis (ms)

Abstract

Background Efficacy and safety of cladribine tablets (CT) has been investigated in patients with early MS and relapsing MS (RMS). Objective Report the AE profile from integrated safety data for CT3.5 mg/kg (CT3.5) monotherapy. Methods The monotherapy oral CT3.5 cohort comprised 923 patients (3432.65 patient years [PY] exposure); 641 patients received placebo (2025.97 PY). Results Mean study period for CT3.5 was 194 weeks; placebo 165 weeks. Adj-AE per 100 PY rates for CT3.5 and placebo respectively: treatment emergent AEs, 103.3 and 94.3; serious AEs, 4.0 and 3.6; serious AEs leading to death, 0.26 and 0.25. For events expected with CT treatment, adj-AE per 100 PY for lymphopenia were 7.94 (CT3.5) and 1.06 (placebo), and for system organ class (SOC) infection and infestations, 24.93 (CT3.5) and 27.05 (placebo); herpes zoster, 0.83 (CT3.5) and 0.20 (placebo). Adj-AE per 100 PY for SOC neoplasms, benign, malignant and unspecified were 1.14 and 1.01, for CT3.5 and placebo, respectively. Conclusions The AE profile for CT3.5 monotherapy has been well-characterised. Lymphopenia was expected from cladribine tablets’ mode of action; herpes zoster was reported more frequently in patients experiencing Grade 3/4 lymphopenia; no clustering of types of malignancy, and no malignancies commonly associated with immunosuppression were observed.