New research reveals that almost half of MS patients treated with AHSCT experienced no disease progression in the subsequent 5 years.
Lead study author Dr. Paolo Muraro, of the Department of Medicine at Imperial College London in the United Kingdom, and colleagues recently reported their findings in JAMA Neurology.
However, Dr. Muraro and team warn that further trials are needed to determine the efficacy and safety of autologous hematopoietic stem cell transplantation (AHSCT), after a small number of patients died within 100 days of treatment.
In AHSCT, a patient's own stem cells are harvested. The patient is then subject to high-dose chemotherapy to eliminate any diseased cells.
Next, the harvested stem cells are returned to the patient's bloodstream, with the aim of restarting normal blood cell production. In simple terms, AHSCT "resets" the immune system.
"We previously knew this treatment reboots or resets the immune system - and that it carried risks - but we didn't know how long the benefits lasted," notes Dr. Muraro.
No MS progression 5 years after AHSCT for 46 percent of patients
For their study, the researchers assessed data from 25 treatment centers across 13 countries, identifying 281 patients with multiple sclerosis (MS) who underwent AHSCT between 1995-2006. Of these patients, 78 percent had a progressive form of MS.
Using the Expanded Disability Status Scale (EDSS), the team evaluated patients' progression-free survival at 5 years after treatment and any improvements in MS symptoms.
An EDSS score of zero represents no disability, seven represents the use of a wheelchair, while 10 represents death from MS. At the beginning of the study, patients had an average EDSS score of 6.5.
Overall, the researchers found that 46 percent of patients experienced no disease progression in the 5 years after treatment.
Patients with RRMS - characterized by inflammatory attacks, or "flare-ups," followed by periods of remission - had the best outcomes, with 73 percent experiencing no worsening of symptoms in the 5 years after AHSCT.
Additionally, patients experienced small improvements in MS symptoms after AHSCT. Patients with progressive MS saw their EDSS score rise by 0.14 a year after treatment, while patients with RRMS experienced a 0.76 increase in their EDSS score.
Patients with a younger age, few immunotherapies prior to AHSCT, and a lower EDSS score at study baseline also showed better outcomes with AHSCT.
Treatment 'carries a small risk of death'
While these findings show promise for the use of AHSCT for patients with MS, the team notes that there were eight deaths in the 100 days after AHSCT, which were thought to have been treatment related.
AHSCT involves aggressive chemotherapy, which can severely weaken the immune system and increase susceptibility to infection.
"In this study, which is the largest long-term follow-up study of this procedure, we've shown we can 'freeze' a patient's disease - and stop it from becoming worse, for up to 5 years.
However, we must take into account that the treatment carries a small risk of death, and this is a disease that is not immediately life-threatening."
Dr. Paolo Muraro
Dr. Muraro notes that, importantly, this study did not include a group of MS patients who did not receive treatment, further highlighting the need for more studies assessing the safety and efficacy of AHSCT.
"We urgently need more effective treatments for this devastating condition, and so a large randomized controlled trial of this treatment should be the next step," he adds.