Dispelling myths in adult SMA
treatment
Assessing
disease stabilisation and progression in SMA
How to assess disease stabilization and progression in
adults?
Myth
Disease
stabilisation and progression can be accurately assessed in adults living with SMA
Reality
Current SMA assessment
scales are limited in their functionality and range and do not support the needs of a growing adult
SMA population
Current
clinical measures focus on motor function and muscle strength1
There is
a growing adult SMA population,2 however,
many of these measures were originally developed for children, and may not reflect adult circumstances3
Summary of
functional outcome measures45
*Under
development.
Reality
Motor function assessments
alone do not represent the full impact of the disease on people living with SMA
Areas included in the 2018 recommendations for SMA diagnosis and
management1,2
Disease management in SMA extends beyond motor function, highlighting
the importance of assessing non-motor outcomes in people with
SMA
Reality
Non-motor outcomes (e.g.
bulbar function) are important for evaluating the impact of DMTs on QoL in adults living with
SMA
Real-world
prospective study, Brakemeier et al. 2024:*
Bulbar
function in
non-ambulatory adults with Type 2 and Type 3 SMA treated with risdiplam (n=25) | Germany6
Real-world
study, Sitas et al. 2024:‡
QoL
improvements in ambulatory
(n=6/31) and non-ambulatory (n=25/31) adults with Type 2 and Type 3 SMA treated with risdiplam |
Croatia7
Top 5 reported QoL improvements
(n=30)7
Real-world data suggest that
DMTs improve
non-motor outcomes and QoL in adults living with
SMA,1,2 therefore, it is important
that these outcomes are routinely assessed to monitor
disease stabilisation or progression
*Data shown
are for patients with available SSQ data.
†Higher SSQ
scores indicate more severe bulbar impairment.
‡Majority of
patients (n=30) reported on QoL before and after treatment.
Reality
Independence is another
important outcome to assess disease stabilisation and progression in individuals with SMA
SMAIS is a
patient-/caregiver-reported
outcome measure that assesses
the amount of
assistance required by
individuals with ambulatory and non-ambulatory SMA to perform daily activities
(with higher scores indicating
greater independence)8,9
SUNFISH Part
2:
Mean change
from baseline in SMAIS-ULM total score over 48 months3
Clinical data
support treatment benefits of DMTs in maintaining or improving independence
in people with SMA, including
those with advanced disease and comorbidities3
*Baseline is
the last measurement prior to the first dose of risdiplam or placebo.
†Patients in
the placebo arm received placebo for 12 months followed by risdiplam
treatment for
36 months. Risdiplam period not shown in this graph.
Reality
Emerging assessment tools
will improve how disease stabilisation and progression are assessed in adults living with SMA
SMAIS8,910
Patient-reported outcome measure to
assess the amount of assistance
required to perform daily
activities
SNIP1112
Measures the joint activation of
the diaphragm and other
inspiratory muscles
ALSFRS-R13,14
Assesses impairment in the daily
routine
6MWT 15,16
Determines aerobic capacity and
endurance in ambulatory
patients
Pittsburgh Fatigability Scale17
Measures perceived fatigability
in older adults
pCO29/pO210
Determines the amount of carbon dioxide
within arterial or venous
blood/effectiveness of the
lungs in pulling oxygen into the bloodstream from the
atmosphere
Myth 1
Myth 2
Myth 3
Myth 4
Myth 5
Myth 6
References
1.
Vuillerot C. Arch Pediatr 2020;27:7S40–4;
2.
State of SMA report. https://www.curesma.org/wp-content/uploads/2023/06/9062023_State-of-SMA_vWeb.pdf.
Accessed 24 April, 2024;
3.
Walter MC, et al. J Neuromuscul Dis 2021;8:543–51;
4.
Muní Lofra R. 2022. Evaluating disease progression and
care provision in spinal muscular atrophy [Doctoral thesis, Universitat Internacional de
Catalunya].
5.
Mercuri E, et al. Neuromuscul Disord 2018;28:103–15; 2. Finkel RS, et al. Neuromuscul
Disord 2018;28:197–207
6.
Brakemeier S, Lipka J, Schlag M, et al. Risdiplam
improves subjective swallowing quality in non-ambulatory adult patients with 5q-spinal
muscular atrophy despite advanced motor impairment. J Neurol. 2024;271(5):2649-2657.
7.
Sitas B, Hancevic M, Bilic K, et al. Risdiplam Real
World Data – Looking Beyond Motor Neurons and Motor Function Measures. J Neuromuscul Dis.
2024;11(1):75-84.
8.
Trundell D, et al. J Neurol Sci 2022;432:120059;
9.
Vázquez-Costa JF, et al. Neurol Ther 2023;12:89–105;
10.
Oskoui M, et al. Presented at MDA 2023 (Poster 158).
11.
Caruso P, et al. J Bras Pneumol 2015;41:110–23;
12.
Cedarbaum JM, et al. J Neurol Sci 1999;169:13–21;
13.
Wohnrade C, et al. Brain Sci 2023;13:110;
14.
Vázquez-Costa JF, et al. Eur J Neurol 2022;29:3666–75;
15.
Stolte B, et al. Eur J Neurol 2020;27:2586–94;
16.
Rodriguez-Torres RS, et al. J Clin Med 2023;12:3458;
17.
Messina Z and Patrick H. Partial pressure of carbon dioxide. StatPearls Publishing NCBI
Bookshelf. 2022; 10. Global Women’s Medicine. https://www.glowm.com/lab-text/item/3#PO2. Accessed 17 April, 2024.