#MSCOVID19.Delaying ocrelizumab dose to let B cells repopulate is not associated with disease activation.


There are two questions

(1) If one continues to take ocrelizumab, will the T cell immunity following COVID-19 vaccination be enough to stop severe COVID-19.

(2) Is it safe to miss a dose to allow B cells to repopulate to allow a B cell-vaccine response.

We dont have a definative answer yet for number 1, but we know that it will not necessarily stop you getting symptomatic COVID-19, and severe COVID can occur in double Vaccinated, I am sure there is some protection, however more and more data addresses number 2. This is a study from UK where there missed a dose of ocrelizumab

Clinical impact of Ocrelizumab extended interval dosing during the COVID-19 pandemic and associations with CD19+B-cell repopulation.Sahi NK, Abidi SMA, Salim O, Abraham R, Kalra S, Al-Araji A.Mult Scler Relat Disord. 2021 Sep 27;56:103287. 

In this retrospective clinical audit, 136 patients with MS received Ocrelizumab during the COVID-19 pandemic. There was no significant difference in clinical relapse rate or radiological activity between 67 patients who received extended interval dosing (EID) (≥30 weeks, mean 48.3 ± 5.9 weeks) compared to standard interval dosing (<30 weeks) with average follow-up of over 4 months. CD19+ B-cell repopulation occurred in 94% (p<0.001) of EID patients at re-infusion and correlated strongly with re-dosing interval (rs=0.738, p=<0.0001) but was not associated with inflammatory disease activity. EID did not impact short-term disease activity, despite significant CD19+ B-cell repopulation and warrants long-term prospective study.

In this retrospective study, 48.3 week mean EID showed no effect on inflammatory disease activity over 19.1 weeks follow-up, despite CD19+ repopulation in almost all (94%) EID patients.

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  • What about the notion of the potential for 6 month or annual booster of covid vaccine? If someone misses an Ocrelizumab dose, has B cell repopulation, gets vaccinated, and seroconverts that is a good outcome. But then returns to regarular dosing schedule of Ocrelizumab only to find oneself needing a booster down the road due to potential waning of vaccine efficacy. Then what? Will boost work if no B cells?

  • I wonder when delaying a dose about the ‘crap gap’ some people say they get when coming close to their next infusion of Ocrevus. It seems to be fatigue mainly or feeling like their previous symptoms are worse? From what I read on here it doesn’t seem like there is a good explanation for it?

    • I would think it is body mass related? 600mm for a 100kg is similar to 300mm to a 50kg in terms of blood antibody concentration. (or 200mm as you have the fixed bone/organ mass etc). 600mm may be pot-on for a 70kg, overdosing for a 50kg, underdosing for a 100kg.

    • But few cycles later body mass probably won’t matter much as there are few cells to deplete, so more to do with rate of repopulation…

      • Good point as you say after a few doses there are fewer B cells I bet the half l8fe is much longer than 26 days

  • One thing missing from this discussion is how many doses of Ocrelizumab have been taken before saying delayed dosing doesn’t matter is true. I continued having relapses after my first 2 rounds and only after the third did my disease progression stabalize. I’ve done 5 rounds now and would consider delayed dosing at this point but even after my 3rd would not have because I was not actually sure the drug was working for me until I got to my 4th round. I’d like to see more on this in these discussions because I’m convinced it matters.

    • You are correct our data was based on 3 or 4 doses. as you say after a single dose disease may reactivate.Once MS stabilizes it is less risky however there is data after one-two doses eg

    • Good point as you say after a few doses there are fewer B cells I bet the half l8fe is much longer than 26 days

      If we view like altuxumsb you need a year of treatment do ,three dosrs

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