Q&A 94: rebound on switching from fingolimod to cladribine

I don’t think cladribine has failed you. Sadly, your relapse occurred in a window before cladribine had a chance to work. This was preventable.

Case study

I am 38 38-year-old woman with relapsing-remitting multiple sclerosis. Earlier this year, I was switched from fingolimod (Gilenya) to cladribine (Mavenclad) due to an HPV infection and abnormal cervical smear. I had stopped fingolimod and was started on cladribine slightly more than 6 weeks after my last dose of fingolimod. My lymphocyte count was 473 on fingolimod, which recovered to 1.47 the week before I started cladribine. Four days after completing the first 5-day cycle of cladribine, I developed numbness in my feet, followed by leg weakness and bladder urgency. I was diagnosed with a spinal cord relapse. My MRI showed a new lesion in my thoracic spine and several new brain lesions. Does this mean that I have not responded to cladribine? I thought cladribine was a highly effective therapy. Should I switch to another DMT?

NOTE: General Substack newsletters and the microsite are free; only Q&A sessions are restricted to paying subscribers. I can't run and maintain the MS-Selfie microsite, so I must pay people to help me do the work. If people want to ask medical questions unrelated to the Newsletters or Podcasts, they either need to become paying subscribers or email (ms-selfie@giovannoni.net) to request a complimentary subscription.

Prof G’s answers

Does this mean that I have not responded to cladribine? Should I switch to another DMT?