A SYSTEMATIC LITERATURE REVIEW OF THE EPIDEMIOLOGY AND NATURAL HISTORY OF SECONDARY PROGRESSIVE MULTIPLE SCLEROSIS PHENOTYPES
Author(s)
Roisin Brennan, MSc1, Mohit Kumar Bhutani, M.Pharmacy2, Nicola Mathieson, BPharm3, Emily Read, PhD4, Isabelle Sutherland, BSc4, Emma Worthington, MPH5, Maeve Freaney, MSc1.
1Novartis Ireland Ltd., Dublin, Ireland, 2Novartis Healthcare Pvt Ltd., Hyderabad, India, 3Novartis Pharma AG, Basel, Switzerland, 4Costello Medical, London, United Kingdom, 5Costello Medical, Cambridge, United Kingdom.
1Novartis Ireland Ltd., Dublin, Ireland, 2Novartis Healthcare Pvt Ltd., Hyderabad, India, 3Novartis Pharma AG, Basel, Switzerland, 4Costello Medical, London, United Kingdom, 5Costello Medical, Cambridge, United Kingdom.
OBJECTIVES: A systematic literature review (SLR) was conducted to identify evidence on the epidemiology and natural history of secondary progressive multiple sclerosis (SPMS) and its phenotypes.
METHODS: This SLR was conducted in accordance with Cochrane Collaboration and PRISMA guidelines. MEDLINE and Embase were searched from 2010 to January 2026 and supplemented by grey literature searches. Records were screened against pre-determined eligibility criteria.
RESULTS: Following screening of 6,507 records, data were extracted from 40 publications (34 studies) reporting epidemiology or natural history data for SPMS phenotypes, including active (aSPMS; presence of relapsing and/or imaging activity, where defined), non-active (naSPMS; no relapsing/imaging activity), relapsing (rSPMS; relapses observed) and non-relapsing SPMS (nrSPMS; absence of relapses). The frequency of phenotypes was reported by 18 studies and varied widely. Among SPMS populations, proportions of naSPMS (8 studies, range: 3.9%-100%) and nrSPMS (5 studies, range: 20.5%-95.7%) were generally higher than aSPMS (10 studies, range: 0%-78.1%) and rSPMS (10 studies, range: 0%-65%). Incidence of nrSPMS was consistently higher (range: 11.9%-74%) than for rSPMS (range: 5.3%-10.2%) in the 3 studies reporting conversion to specific SPMS phenotypes from MS. Years to transition from MS diagnosis was longer for nrSPMS (mean: 11.3; median: 13) than for rSPMS (mean: 9.4; median: 10.3) across 2 studies. Mean transition time was comparable between aSPMS (15.1 years) and naSPMS (14.7 years) phenotypes. Natural history data were reported by 21 studies and highlighted similar or worse disability progression in aSPMS and rSPMS than naSPMS and nrSPMS.
CONCLUSIONS: The evidence suggests that although aSPMS and rSPMS are less frequent than naSPMS and nrSPMS, time to onset and disability progression are comparable or worse. However, the evidence on SPMS phenotypes was limited in volume and depth, with definitions often poorly reported. Furthermore, few studies statistically compared outcomes between phenotypes, underscoring the need for further research.
METHODS: This SLR was conducted in accordance with Cochrane Collaboration and PRISMA guidelines. MEDLINE and Embase were searched from 2010 to January 2026 and supplemented by grey literature searches. Records were screened against pre-determined eligibility criteria.
RESULTS: Following screening of 6,507 records, data were extracted from 40 publications (34 studies) reporting epidemiology or natural history data for SPMS phenotypes, including active (aSPMS; presence of relapsing and/or imaging activity, where defined), non-active (naSPMS; no relapsing/imaging activity), relapsing (rSPMS; relapses observed) and non-relapsing SPMS (nrSPMS; absence of relapses). The frequency of phenotypes was reported by 18 studies and varied widely. Among SPMS populations, proportions of naSPMS (8 studies, range: 3.9%-100%) and nrSPMS (5 studies, range: 20.5%-95.7%) were generally higher than aSPMS (10 studies, range: 0%-78.1%) and rSPMS (10 studies, range: 0%-65%). Incidence of nrSPMS was consistently higher (range: 11.9%-74%) than for rSPMS (range: 5.3%-10.2%) in the 3 studies reporting conversion to specific SPMS phenotypes from MS. Years to transition from MS diagnosis was longer for nrSPMS (mean: 11.3; median: 13) than for rSPMS (mean: 9.4; median: 10.3) across 2 studies. Mean transition time was comparable between aSPMS (15.1 years) and naSPMS (14.7 years) phenotypes. Natural history data were reported by 21 studies and highlighted similar or worse disability progression in aSPMS and rSPMS than naSPMS and nrSPMS.
CONCLUSIONS: The evidence suggests that although aSPMS and rSPMS are less frequent than naSPMS and nrSPMS, time to onset and disability progression are comparable or worse. However, the evidence on SPMS phenotypes was limited in volume and depth, with definitions often poorly reported. Furthermore, few studies statistically compared outcomes between phenotypes, underscoring the need for further research.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
EPH78
Topic
Epidemiology & Public Health
Disease
Neurological Disorders, No Additional Disease & Conditions/Specialized Treatment Areas