Dr Paolo Muraro talks stem cell treatments and new research
We spoke with leading expert in the field of stem cells and MS research, Dr Paolo Muraro from Imperial College London, about making sense of the study and what it may mean for people with MS.
Hi Paolo, thanks for talking to us today. What are your first impressions on this new study?
This new study is exciting, as it shows a near-complete suppression of new MS activity for several years following AHSCT in people with previously highly active MS.
How does this latest trial differ from other HSCT studies?
All HSCT studies follow the same basic procedure:
The chemotherapy used can vary from trial to trial and centre to centre. In this trial, one of the most aggressive types of chemotherapy was used, aiming to eradicate all immune cells in the body, including those in the central nervous system.
This is in contrast to previous AHSCT trials where lower-intensity chemotherapy has been used to more selectively target the immune system. These trials are less risky and better tolerated. In this new study, the researchers also purified the stem cells ensuring only immature stem cells were included in the final sample.
Does this story change who may benefit from HSCT?
No, similar to previous studies, the best response was observed in people with highly active MS. This is the same group of people who have been shown to benefit from AHSCT in other trials.
The researchers found patients who progressed after treatment did not have any evidence of inflammatory activity. This confirms previous thinking that HSCT is not suitable for people with progressive forms of MS who have accumulated long-standing disability no longer related to ongoing inflammatory damage. For these people, the risks of treatment outweigh any potential benefit.
How do the results today compare with currently licensed DMTs?
It’s hard to assess as no direct comparisons have been made with standard therapies. However, none of the DMTs currently approved have been reported to achieve a similar level of control of the condition.
Are there any trials in the UK that follow the new trial protocol?
No. There is only one AHSCT trial currently open in the UK. This is the MIST trial in Sheffield, and it uses low-intensity chemotherapy.
Is the new trial protocol available for treatment of MS outside a trial?
Again no – similar schemes using this type of chemotherapy are used to treat cancer, but not MS.
Why hasn’t the new trial protocol been more widely adopted?
High-intensity chemotherapy, as used in this study, is associated with higher toxicity. Additionally, the benefit of purifying the stem cells is currently unclear, and needs more investigation.
Although the methods in this study may result in greater control over MS activity, more data is needed in order to be confident this therapy is more effective than the moderate-intensity chemotherapy, currently used by most European centres and in a US trial.
So, what next?
The next challenge for MS researchers is to find out whether AHSCT is superior in efficacy to approved DMTs and importantly, whether it is acceptably safe for treatment of MS.
The safety of this kind of therapy is improving all the time, but there’s still a substantial risk to be carefully considered.
To get a reliable answer on whether AHSCT will be an effective MS therapy, we need large, randomized, and controlled clinical trials, testing efficacy and safety of the treatment against the most effective approved DMTs.
Thank you Paolo for giving up your time to talk to us today.
So what does this all mean for people with MS?
If someone has progressive MS, but is still having relapses that are causing damage (and therefore worsening disability), the treatment may be able to stop this.
What the treatment can’t do is reverse damage already done – in patients with progressive MS with no relapses, this treatment might not show any benefits so therefore might not be worth the risk.
We appreciate it can be extremely frustrating to hear about new developments which aren’t helpful to people with progressive MS. Work to find an effective treatment for progressive MS is still ongoing, with multiple clinical trials underway.
Finding out if you are potentially suitable for HSCT
Ultimately, deciding whether to have HSCT is a personal decision, where all the benefits and risks need to be weighed up.
We would strongly encourage people with MS thinking about undergoing HSCT to discuss this carefully with a specialist health care professional such as their neurologist or MS nurse before making any decisions.