ACTRIMS2021. Vaccination responses after cladribine


This week is ACTRIMS2021 week and I could wait until the end of the week to give you the news but public domain, is public domain and for some people a few days will be of value, especially if you have been taking oral cladribine and you are being offered a COVID-19 vaccine, this may help you sleep abit easier.

The manufacturers of CLAD “let the baton slip” in 2010/2011 when development of “Movectro” was canned. The CLADLADS from BartsMS took up the baton until oral cladribine resurfaced and our baton was stolen…OK we gave it back to ProfG and friends and it was developed again.

However the termination of the programmes in 2010 meant there were questions that were unanswered and there is big question unanswered and that is what is the vaccination response like?

The manufacturers of oral cladribine have been doing extensive studies. It happens that a number of people have recieved vaccinations as part of their annual Flu protection or to protect against chickpox/Shingles. The numbers of people involved were small, but the good news is that post-vaccination antibody levels in people treated with oral cladribine for relapsing MS remained at levels that offer protective immunity against seasonal flu and chickenpox. This appears to be good news and maybe we will report more when the work is presented.

The experiment of what happens in people treated with oral cladribine tablets and the COVID-19 vaccine has begun or will begin shortly.

P059 / P059 – Analysis of Influenza and Varicella Zoster Virus Vaccine Antibody Titers in Patients with Relapsing Multiple Sclerosis Treated with Cladribine Tablets

S. Roy, U. Boschert;
Background: There is a lack of data available to determine the effect of cladribine tablets (CladT) on the antibody response to vaccination in patients with relapsing multiple sclerosis (MS).
Objectives: To investigate the immunoprotective response to seasonal influenza and varicella zoster virus (VZV) vaccination in patients treated with CladT (3.5mg/kg over 2 years) for relapsing MS.
Methods: Blood samples collected during the MAGNIFY-MS study (NCT03364036) from 9 patients with relapsing MS treated with CladT who received seasonal influenza (n=8) or VZV vaccinations (n=1; Shingrix) as a standard of care were retrospectively analyzed. Two control blood samples (baseline sample before starting CladT and closest sample available just before vaccination) and two post-vaccination blood samples (closest sample available after vaccination) were examined. Quantitative antibody titers in response to the seasonal influenza and VZV vaccine were measured by hemagglutination inhibition (HAI) assay and Enzyme-Linked Immunosorbent Assay (ELISA), respectively. The seroprotection titer level for the seasonal influenza vaccine is considered ≥40, and was ≥100 IU/L for the VZV vaccine.
Results: Influenza: All patients vaccinated against influenza A and B during year 1 or 2 of CladT treatment retained seroprotection titers of ≥40 in post-vaccination samples across all strains present in the vaccine administered. The number of seropositive patients (HAI ≥40) with a ≥4-fold and ≥2-fold increase against at least 1 strain in post-vaccination titers were 3/8 and 7/8, respectively. VZV: Post-vaccination antibody titers were 40-fold increased over the protective titer at all time points (titres >4748 IU/L).
Conclusions: In this small retrospective investigation, post-vaccination antibody titers in patients treated with CladT for relapsing MS remained at levels that offer protective immunity against seasonal influenza and VZV.

COI: Multiple including working with the manufacturers of oral cladribine…yep I know they call them cladribine tablets:-).

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  • This is good news, thanks for sharing MD. Given the impact Clad has on memory b-cells, this study seems to support your assessment of “it’s the t-cells” which are important for adequate vaccine responses. It’s nice to get some validation every once in awhile 😉

    Does not look like I will be able to get access to a COVID vaccine before switching to Clad, so the findings in this study are reassuring and if I get the jab between year 1 and 2 of Clad I should make an “adequate” response.

      • Must be nice to have so many data points, as the majority of the neuros across the pond have very little experience or knowledge of clad. Sometimes I feel like I know more about the drug than they do!

        Nevertheless, I look forward to the results of your clad cohort…..which I hope you will post.

        • The FDA has not done CLAD a favour and people in the USA dont understand Cladriine…just watch ProfKs You tube videos…”reassuringly simple” but in terms of our CLAD cohort, Israel is miles ahead. They have vacccinated at least 3000 people with MS, however I think BartsMS can be proud. We have done a tenth of the whole of Israel already…well done the team from 11D!!!!! (Eleventh floor at the Royal London Hospital)

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