2021 CMSC Annual Meeting

Updated Post-Approval Safety of Cladribine Tablets in the Treatment of Multiple Sclerosis, with Particular Reference to Respiratory Viral Infections and COVID-19


Background: Several integrated analyses have reported on the safety of cladribine tablets 10 mg (3.5 mg/kg cumulative dose over 2 years [CladT3.5]) during clinical development for treatment of relapsing multiple sclerosis (MS). Additional real-life safety data have accrued since the approval of CladT3.5 in many countries worldwide. In recent months the COVID-19 pandemic has become a concern for MS patients and their healthcare providers in terms of the associated safety of their disease-modifying therapy. Objectives: To update on the post-approval safety profile of CladT3.5 in patients with relapsing MS, including COVID-19 and other respiratory viral infections. Methods: Serious and non-serious adverse events (AEs) from post-approval sources (including spontaneous individual case safety reports, non-interventional post-marketing studies, and reports from other solicited sources) are presented to July 2020. AE rates are shown as crude incidences. Results: 3357 AEs were spontaneously reported for the first 18,463 patients who received CladT3.5 post-approval; 435 (13%) of these events were serious. Crude incidences for AEs of special interest: severe lymphopenia, 0.21%; herpes zoster, 1.07%; tuberculosis, 0.05%; severe infections, 1.23%; progressive multifocal leukoencephalopathy, 0%; opportunistic infections, 0.04%; malignancies, 0.23%; and congenital anomalies, 0%. The pattern of respiratory viral infections (typically non-serious) with post-approval use of CladT3.5 was also consistent with that of the clinical development program; crude incidences: H1N1 influenza, 0.01%; influenza, 0.68%; viral infection, 0.27%; and viral upper respiratory tract infection, 0.04%. As of 7 September 2020, the Merck KGaA safety database included 85 cases of suspected COVID-19 in CladT3.5-treated patients (confirmed by test, n=38). An update on latest findings on COVID-19 infections will be presented, including analysis of time of infection since treatment where available. Conclusions: The safety profile of CladT3.5, including respiratory viral infections, is consistent with previously published integrated safety analyses of the clinical development data.