Q&A 76: half-dose ocrelizumab

I received a phone call from my centre informing me that my next dose would be halved to reduce the cancer risk or other adverse effects in particular serious infections. Is this correct?

Case study

Have you heard of halving the dose of ocrelizumab (Ocrevus) for patients on long-term treatment (300mg per infusion instead of 600mg after the first 2 years), and what are the clinical reasons for this?

This happened to me two years ago. However, after six months of worsening symptoms (but stable MRI ), I successfully argued to have my dose taken back up to the recommended 600mg at my next infusion. I am relieved.

I was diagnosed with RRMS in 2006. Ocrelizumab is my fifth treatment, which I began in October 2018 after a significant relapse on glatiramer acetate (Copaxone). In late 2023, just before my next infusion, I received a phone call from my centre informing me that my next dose would be halved because the head of the MS centre had decided it was best to halve the dose for long-term treatment to reduce cancer risk or other adverse effects of B cell depletion in particular serious infections.

When I asked, I was not given any further information on the reasons then or at any other point, and my request to stay on the full dose was denied. Other patients I know in the clinic also had their dose halved with the same lack of explanation.

I'd like to hear your thoughts on this practice of halving the dose of ocrelizumab (Ocrevus) and what, if any, clinical reasons back it up.

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Answers

Q: Have you heard of halving the dose of ocrelizumab (Ocrevus) for patients on long-term treatment (300mg per infusion instead of 600mg after the first 2 years), and what are the clinical reasons for this?

Is this a catch? I am being asked whether this opinion is correct:

“....to halve the dose for long-term treatment to reduce cancer risk or other adverse effects of B cell depletion in particular serious infections.”

Google AI - Gemini’s Answer

I thought I would ask Gemini 2.0 first, and this is what it said: