Prof G will ocrelizumab and rituximab prevent SPMS?
Just back from the COMBAT-MS stakeholders meeting in Pasadena with the Kaiser (Kaiser Foundation Research Institute) and Swedish (Karolinska Institute) trial teams, PCORI (Patient-Centered Outcomes Research Institute) and many brave an wonderful people with MS and their families.
The COMBAT-MS study (NCT03193866) is recruiting well and is on schedule to deliver very important comparative data on the effectiveness of rituximab in real-life. The full title of the study is ‘COMparison Between All immunoTherapies for Multiple Sclerosis. An Observational Long-term Prospective Cohort Study of Safety, Efficacy and Patient’s Satisfaction of MS Disease Modulatory Treatments in Relapsing-remitting Multiple Sclerosis’. In short, COMBAT-MS will be comparing Rituximab with Natalizumab, Fingolimod, Alemtuzumab, Interferon-beta, Glatiramer acetate and Dimethyl Fumarate. Because the use of alemtuzumab seems to be quite limited in Sweden, with the majority of patients going onto rituximab, the study will not have enough power to compare rituximab with alemtuzumab. This a great pity because the real question I have is how does anti-CD20 therapy compare to our top-guns, i.e. alemtuzumab and HSCT. This question is becoming a priority for me.
We had a comprehensive safety update from the COMBAT-MS trial team, which will be presented later this year. However, the safety profile of rituximab is broadly in keeping with what is seen in rheumatology, with a few interesting exceptions. However, the overall safety profile will help with the adoption of rituximab as a treatment of MS in resource-poor environments.
I included in my presentation on why I think anti-CD20 is not good enough to treat MS in the long term and why we need to think beyond NEDA. I presented data, mainly from ocrelizumab, that shows MS continues to smoulder away on ocrelizumab despite patients being NEDA. The response to the data was what we are seeing was simply secondary progressive MS. Yes and no. It may be a secondary progressive disease, but the pathology driving smouldering MS (microglial activation, slowly expanding lesions, subpial cortical lesions, intrathecal immunoglobulin production, demyelination, mitochondrial toxicity and energy failure, oxidative damage, delayed axonal loss, synaptic pruning, premature ageing, etc.) are all present at the very earliest stages of the disease, even the asymptomatic stage of the disease, i.e. radiologically isolated syndromes. This is why I don’t think SPMS really exists and why MS is one and not two or three diseases.
The construct that MS has distinct phases, an early inflammatory and a delayed degenerative phase, is artificial and comes from the Pharma industry’s need to get interferon-beta licensed under the orphan drug act, i.e. MS had to have a prevalence of fewer than 200,000 affected people for the orphan drug act to apply. The only way to get the numbers down to less than 200,000 was to salami-slice up MS into three diseases, i.e. RRMS, SPMS and PPMS. Later on, a fourth category, CIS (clinically isolated syndrome) was added. However, CIS has largely disappeared as a category because of diagnostic creep and the earlier diagnosis of MS with the evolving definition of MS based on the newer versions of the McDonald criteria. Having looked hard I can find no scientific justification for making SPMS a different disease.
In my opinion, smouldering MS and the pathologies driving it do not seem to be anti-CD20 responsive. If they were then we would see a much better impact of anti-CD20 on brain volume loss, disease improvement and the slowly expanding lesion. What does this mean for people with MS? It means that anti-CD20 therapies may be a good platform to start on but you will require additional add-on therapies to stop smouldering MS. Can I please urge you to re-read Stephen Hauser’s case report below. You may argue that one swallow doesn’t make a summer, but Stephen Hauser implied two year’s ago in a response to a question at ECTRIMS that anti-CD20 was not the panacea everyone wants it to be and that a lot of his long-term rituximab-treated patients were now secondary progressive, i.e. they had smouldering MS.
The concept of smouldering MS is a difficult one for people in the field to grasp. Why? It is because NEDA-3 has become de-facto what defines MS. We need to move beyond what we can see and measure and focus on end-organ markers of disease activity, i.e. whole brain and regional or grey matter volumes, the expanding MS lesions, neurofilament levels and more sensitive clinical outcomes. An EDSS view of the world is simply too narrow. We need to look at cognition, visual function and more sensitive functional tests of different neuronal systems. One of the attendees was horrified when I said that the best thing that could happen to the field is if we could automate the neurological examination using a validated technology platform. The idea of using a neurologist to assess eye movements and balance, when it can be done so much better with eye tracking systems and balance sensors, shocked this individual. Bring on the robots and maybe our worldview of MS, in particular, smouldering MS, would change.
I was also able to deliver good news about our WHO Essential Medicine List (EML) application that includes ocrelizumab as one of the three drugs and rituximab as a suitable replacement for ocrelizumab if access to ocrelizumab is a problem. If our EML application is successful this will allow us to pressurise governments to prioritise the treatment of MS in low prevalence countries. I explained to the group that what had started out for me as an ‘Essential Off-label DMT list’ in 2014, may become an official WHO-backed Essential DMT list in 2019. I am holding thumbs we get MS onto the EML, it needs to be there for many reasons.
I also covered in my talk alternative hypotheses, i.e. that MS may be due to a virus and that our current world-view of MS being an autoimmune disease driven by T and B-cells may be wrong. I briefly presented the B-cell-EBV hypothesis and our proposed EBV vaccination trial. I stressed that we need to use anti-CD20 as a tool to explore the EBV hypothesis and the good news is that Fredrik Piehl is going to explore EBV biomarkers as part of the COMBAT-MS study.
I used my lecture to represent my ‘marginal gains’ philosophy as it applies to treating MS and how we need to manage MS holistically and focus on the small things that may make a big difference to MS outcomes in the future. This is only the second time that I have presented this concept to my peer group, but it is something that still needs work to make it sticky.
The following are my slides from the meeting, which you can download from my slide sharing site.
I would like to thank PCORI and the Kaiser team for including me in this study and for your wonderful hospitality. I have little doubt that the COMBAT-MS study is going to help change the way the MS community treats MS globally. I would also like to thank the MSers who attended and spoke at the meeting; you are are the reason why we are doing what we do.
von Büdingen et al. Onset of secondary progressive MS after long-term rituximab therapy – a case report. Ann Clin Transl Neurol. 2016 Dec 20;4(1):46-52.
A patient with relapsing multiple sclerosis (RMS) was treated with a standard immunomodulatory therapy, but due to ongoing disease activity was switched to rituximab. Relapses ceased, but secondary progressive MS (SPMS) eventually appeared, associated with new focal spinal cord white matter lesions. Cerebrospinal fluid (CSF) showed persistent oligoclonal bands (OCB) and clonally related B cells in CSF and peripheral blood. The treatment escalation approach failed to prevent evolution to SPMS, raising the question of whether initiation of B-cell depleting therapy at the time of RMS diagnosis should be tested to more effectively address the immune pathology leading to SPMS.