Delaying Ocrelizumab for up to 12 weeks


The ocrelizumab dosing is done every twenty four weeks. I have suggested that this may be overkill and is done more than is needed. However delaying treatment without evidence is not sensible. We have suggested doing a trial. Based on the phase II trial it looks like it takes about 60 weeks for the B cells to recover so for some dosing every 24 weeks maybe too much. Is it safe.? During the COVID-19 pandemic you have been asked to delay treatment. In this study they delayed treatment for up to 3 months without a relapse. So if you are asked to delay a short while hopefully this post will allay some fear.

Barun B, Gabelić T, Adamec I, Babić A, Lalić H, Batinić D, Krbot Skorić M, Habek M. Influence of delaying ocrelizumab dosing in multiple sclerosis due to COVID-19 pandemics on clinical and laboratory effectiveness. Mult Scler Relat Disord. 2020 Dec 21;48:102704. doi: 10.1016/j.msard.2020.102704. 

Objective: To evaluate clinical and laboratory effects of delaying ocrelizumab infusions during the COVID-19 pandemics in people with multiple sclerosis (pwMS).

Methods: We have retrospectively searched our electronic database and identified 33 pwMS who had a delay in treatment due to COVID-19 pandemics. The following data were extracted: age, sex, multiple sclerosis (MS) phenotype: relapsing-remitting (RRMS) or primary progressive multiple sclerosis (PPMS), disease duration, Expanded Disability Status scale (EDSS), previous disease modifying therapy (DMT), number of ocrelizumab cycles prior to the lockdown, dates of first ocrelizumab infusion, last ocrelizumab infusion prior to the lockdown and delayed ocrelizumab infusion after the lockdown. Flow cytometry results, relapses and EDSS progression prior to the delayed ocrelizumab infusion after the lockdown were extracted.

Results: The mean time between two ocrelizumab infusion during the lockdown was 7.72±0.64 (range 6.07 to 8.92) months. The mean time between last ocrelizumab infusion and the lymphocyte sampling prior to post COVID infusion was 6.59±0.95 (range 5.18 to 8.49) months. In this period, none of the studied patients had a relapse. In a multivariable linear regression analysis, time from last ocrelizumab infusion to lymphocyte sampling prior to the next infusion was the only significant predictor for CD19+ B cells count, when corrected for the number of previous ocrelizumab cycles and MS phenotype (RRMS or PPMS) (B=7.981, 95% C.I. 3.277-12.686, p=0.002).

Conclusions: We have not shown clinical consequences of delaying ocrelizumab due to COVID-19 pandemics. However, the delay in dosing of ocrelizumab was an independent predictor of repopulation of B cells.

CoI: multiple

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  • As an ocrelizumab patient I can tell you that although from this research finds that the b cells do not repopulate fully till 60 weeks they are starting to repopulate from 3 and a half months after the infusion based on the way I feel. Yes this isn’t scientific and perhaps anecdotal, but nevertheless less surely some b cells start to do their work from the three and a half month mark and even if they don’t produce a classic relapse would you say they are reinitialising the ‘smouldering MS that seems to be in the real problem with MS and therefore the problem may be the gap between doses may be too long in some cases?

    • This 60 weeks is the blood and this is the time to be back to baseline levels as you say the lymph glands and bone marrow will not doubt be quicker. The ones making a vaccine response appear much quicker that the ones we think are imortant in MS. About 5% of people have started to repopulate before the next dose.

  • Mouse doctor, happy new year! Thank you for keeping us posted on latest. But please enjoy a bit of holiday too! I’m afraid it looks like odds of getting vaccine before my next scheduled infusion are dwindling….My State provided an interactive map of available vaccines. One only needs to search each location for vendor and contact each vendor if taking appointments yet.

  • Here in the states we are dosed with Ocrevus every 6 months (26 weeks). I personally felt it was overkill and then looking at my blood results, it most definitely was! So my last infusion was end of January 2020 6 months after last one. I looked at blood work and realized I could’ve waited longer as absolute lymphs were still extremely low. In July I decided not to go forth with another infusion. I did however have my blood drawn & my absolute lymphocytes were still at basically zero. In a few more weeks, it’ll be a year without Ocrevus (or any other med). I am calling in this week to my neuro to see about a repeat on blood work, especially with vaccine now here. I will try and remember to update when and if I do receive another blood workup & let you know if there has been any repopulation & how much!

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