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Cladribine Tablets and vaccination

From the US Prescribing Information:1

• Administer all immunizations according to immunization guidelines prior to starting Cladribine Tablets.

• Administer live-attenuated or live vaccines at least 4 to 6 weeks prior to starting Cladribine Tablets, because of a risk of active vaccine infection.

• Vaccination of patients who are antibody-negative for varicella zoster virus is recommended prior to initiation of Cladribine Tablets.

• Avoid vaccination with live-attenuated or live vaccines during and after treatment with Cladribine Tablets while the patient's white blood cell counts are not within normal limits.

There are limited data available on the efficacy of vaccines in patients treated with Cladribine Tablets. As of February 2021, data from patients who received vaccines while treated with Cladribine Tablets during the CLARITY, MAGNIFY-MS and CLOCK-MS studies have been analyzed.

Analysis of Influenza and Varicella Zoster Virus Vaccine Antibody Titers in Patients with Relapsing Multiple Sclerosis Treated with Cladribine Tablets

Roy S, Boschert U

Presented at the ACTRIMS Virtual Congress, 25–27 February, 2021

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• Retrospective analysis of seroprotective antibody levels against varicella zoster (n=3) or seasonal influenza (n=12) in patients who received vaccinations before or during treatment with Cladribine Tablets in the MAGNIFY-MS study

• The ongoing MAGNIFY-MS study is a single-arm open-label Phase IV clinical trial intended to determine the onset of action of Cladribine Tablets by frequent MRI assessment in patients with highly active relapsing MS

Evaluating the Impact of Cladribine Tablets on the Development of Antibody Titers: Interim Results from The CLOCK-MS Influenza Vaccine Substudy

Wu G.F, Boschert U, Hayward B et al

Presented at ACTRIMS Forum, 25–27 February, 2021

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• Contains information on seroprotective antibody levels against seasonal influenza in a subset of patients (n=4) with relapsing-remitting MS and secondary progressive MS who received vaccinations during treatment with Cladribine Tablets in the CLOCK-MS study

• The ongoing CLOCK-MS study is a randomized open-label US-based Phase IV biomarker study to assess the effect of Cladribine Tablets on central nervous system biomarkers in patients with RMS 


1. MAVENCLAD® US PI, April 2019