1. Brain Sci. 2023 Oct 7;13(10):1419. doi: 10.3390/brainsci13101419.

 Safety and Efficacy of Nusinersen and Risdiplam for Spinal Muscular Atrophy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

 Author information:

(1)Department of Neurology, Shengjing Hospital of China Medical University, Shenyang 110055, China.

 OBJECTIVE: We performed a systematic review and meta-analysis of the efficacy and safety of nusinersen and risdiplam in the treatment of spinal muscular disease (SMA).

METHODS: We screened the literature published in Pubmed, Web of Science, Embase, and Cochrane before July 2023 to conduct randomized controlled trials to test the treatment of SMA patients with nusinersen and risdiplam. The data were analyzed using Review Manager 5.4 software and Stata version 15.0 software.RESULTS: A total of six randomized controlled trials were included, involving 728 SMA patients, to synthesize evidence. It is reported that nusinersen treatment was beneficial for increasing the score of the Hammersmith Functional Motor Scale-Expanded (HFMSE) (WMD: 4.90; 95% CI: 3.17, 6.63; p < 0.00001), Revised Upper Limb Module (RULM) (WMD: 3.70; 95% CI: 3.30, 4.10; p < 0.00001), and Hammersmith Infant Neurological Evaluation Section 2 (HINE-2) (WMD: 5.21; 95% CI: 4.83, 5.60; p < 0.00001). In addition, the risdiplam treatment group also showed statistically significant improvements in the HFMSE score (WMD:0.87; 95% CI: 0.05, 1.68; p = 0.04), the 32-item Motor Function Measure (MFM32) (WMD:1.48; 95% CI: 0.58, 2.38; p = 0.001), and (WMD: 1.29; 95% CI: 0.57, 2.01; p = 0.0005). Nusinersen and risdiplam did not cause a statistically significant increase in the RULM score for adverse events (OR: 0.93; 95% CI: 0.51, 1.7; p = 0.82) and for severe adverse events (OR: 0.77; 95% CI: 0.47, 1.27; p = 0.31).CONCLUSION: Our analysis found that nusinersen and risdiplam treatment showed clinically meaningful improvement in motor function and a similar incidence rate of adverse events compared with the placebo. Further research should be carried out to provide a direct comparison between the two drugs in terms of safety and efficacy.

2. Pharmacotherapy. 2024 Jan;44(1):97-105. doi: 10.1002/phar.2866. Epub 2023 Aug 21.

 Efficacy of risdiplam in spinal muscular atrophy: A systematic review and meta-analysis.

 Author information:

(1)Health and Social Research Center, Universidad de Castilla - La Mancha, Cuenca, Spain.

 This systematic review and meta-analysis aimed to assess the efficacy and safety of risdiplam on motor and respiratory function in spinal muscular atrophy (SMA). We systematically searched Medline, Scopus, Web of Science, and the Cochrane Library from inception to March 2023. We included pre-post studies that determined the effect of risdiplam on the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND), the 32-item Motor Function Measure (MFM32), the Revised Upper Limb Module (RULM), the Hammersmith Functional Motor Scale - Expanded (HFMSE), respiratory function, and the proportion of risdiplam-related adverse events in a population with SMA (phenotypes 1 and 2/3). Meta-analyses were also performed where possible. Eleven studies were included. After 12 months of treatment, 57% of participants with SMA1 achieved a CHOP-INTEND score ≥ 40 points, and more than half were able to feed orally and had head control. In SMA2/3, MFM32, RULM, and HFMSE increased by 2.09 (1.17, 3.01), 1.73 (1.25, 2.20), and 1.00 (0.40, 1.59) points, respectively. Efficacy on respiratory function in SMA2/3 was inconsistent. Finally, 16% of participants experienced adverse events, but serious adverse events could not be quantified due to a lack of cases. The limited available evidence suggests that risdiplam is an effective and safe drug for the treatment of SMA. In addition, long-term clinical benefit may be partly determined by the stage of disease at which treatment is initiated.

3. Paediatr Respir Rev. 2023 Dec;48:65-71. doi: 10.1016/j.prrv.2023.06.004. Epub 2023 Jul 13.

 Author information:

(1)Clinical Pharmacy Department, Faculty of Pharmacy, Istinye University, Istanbul, Türkiye. Electronic address: altaiianmar@gmail.com.

 Spinal muscular atrophy (SMA) is a severe hereditary lower motor neuron disorder characterised by degeneration of alpha motor neurons in the spinal cord, resulting in progressive weakness and paralysis of proximal muscles. A systematic literature search was carried out by using PRISMA guidelines and searching through different databases that could provide findings of evidence on the health outcomes of the approved therapies for the management of paediatric SMA type 1 regarding efficacy with follow-up in terms of motor and respiratory functions and the tolerability and incidence of adverse drug reactions (ADRs) post-treatment from real-world publications. Half of the publications (50%) had a prospective observational design. Eight studies (66.7%) assessed nusinersen, and three studies (25%) assessed onasemnogene abeparvovec with a duration of follow-up ranging from 6 months to 3 years to evaluate the motor and respiratory functions using different assessment tools, hospitalisation rates, and the tolerability and incidence of ADRs post-treatment. The three currently approved treatments for SMA type 1 provided good support and health outcomes in terms of motor function, respiratory outcomes, reduction of hospitalisations, and improvement of survival. Nevertheless, uncertainties regarding continued improvement after long-term illness and the generalizability of results are still unknown.

4. Muscle Nerve. 2023 May;67(5):407-411. doi: 10.1002/mus.27804. Epub 2023 Mar 17.

 Risdiplam in non-sitter patients aged 16 years and older with 5q spinal muscular atrophy.

 Author information:

(1)Neuromuscular Unit, Hospital Universitario y Politécnico la Fe, Instituto de Investigación Sanitaria la Fe, València, Spain.

 INTRODUCTION/AIMS: Risdiplam has been approved for the treatment of patients with 5q spinal muscular atrophy (SMA), but data from type 2 non-sitter patients are lacking. In this study we describe our experience regarding the use of risdiplam in a series of type 2 non-sitter patients.

METHODS: Type 2 SMA patients over 16 years of age were administered risdiplam through the expanded access program (NCT04256265). Patients were followed-up with a battery of scales and clinical measures.

RESULTS: Six non-sitter patients (17 to 46 years old) were treated with risdiplam. One patient reported mild adverse events (dyspepsia and headache). After 1 year of treatment, all patients showed clinically meaningful improvements in at least one scale and none of them showed any clinically meaningful deterioration. Two patients showed a clinically meaningful increase in body mass index (>5%) and two others scored higher on the Revised Upper Limb Module (>2 points). Moreover, five patients had clinically meaningful improvements on the Egen Klassifikation 2 scale (>2 points), including the motor (axial and upper limbs), bulbar (speech and swallowing), and respiratory (coughing) domains. Four subjects achieved at least one of the goals set with the Goal Attainment Scale (GAS).

DISCUSSION: This series suggests that risdiplam is safe and may be effective in non-sitter SMA patients older than 16 years of age. In these patients, functional scales and the GAS would be more sensitive than motor scales to detect changes, because they include axial, bulbar, and respiratory domains. Larger studies are needed to confirm these results.

5. J Neurol. 2023 May;270(5):2531-2546. doi: 10.1007/s00415-023-11560-1. Epub 2023 Feb 3.

 Two-year efficacy and safety of risdiplam in patients with type 2 or non-ambulant type 3 spinal muscular atrophy (SMA).

 Author information:

(1)Departments of Pediatrics and Neurology and Neurosurgery, McGill University, Montreal, Canada. maryam.oskoui@mcgill.ca.

 Risdiplam is an oral, survival of motor neuron 2 (SMN2) pre-mRNA splicing modifier approved for the treatment of spinal muscular atrophy (SMA). SUNFISH (NCT02908685) Part 2, a Phase 3, randomized, double-blind, placebo-controlled study, investigated the efficacy and safety of risdiplam in type 2 and non‑ambulant type 3 SMA. The primary endpoint was met: a significantly greater change from baseline in 32-item Motor Function Measure (MFM32) total score was observed with risdiplam compared with placebo at month 12. After 12 months, all participants received risdiplam while preserving initial treatment blinding. We report 24-month efficacy and safety results in this population. Month 24 exploratory endpoints included change from baseline in MFM32 and safety. MFM‑derived results were compared with an external comparator. At month 24 of risdiplam treatment, 32% of patients demonstrated improvement (a change of ≥ 3) from baseline in MFM32 total score; 58% showed stabilization (a change of ≥ 0). Compared with an external comparator, a treatment difference of 3.12 (95% confidence interval [CI] 1.67-4.57) in favor of risdiplam was observed in MFM-derived scores. Overall, gains in motor function at month 12 were maintained or improved upon at month 24. In patients initially receiving placebo, MFM32 remained stable compared with baseline (0.31 [95% CI - 0.65 to 1.28]) after 12 months of risdiplam; 16% of patients improved their score and 59% exhibited stabilization. The safety profile after 24 months was consistent with that observed after 12 months. Risdiplam over 24 months resulted in further improvement or stabilization in motor function, confirming the benefit of longer-term treatment.

6. Eur J Neurol. 2023 Jul;30(7):1945-1956. doi: 10.1111/ene.15499. Epub 2022 Aug 1.

 Risdiplam in types 2 and 3 spinal muscular atrophy: A randomised, placebo-controlled, dose-finding trial followed by 24 months of treatment.

 Author information:

(1)Pediatric Neurology Institute, Catholic University and Nemo Pediatrico, Fondazione Policlinico Gemelli IRCCS, Rome, Italy.

 BACKGROUND AND PURPOSE: Spinal muscular atrophy (SMA) is caused by reduced levels of survival of motor neuron (SMN) protein due to deletions and/or mutations in the SMN1 gene. Risdiplam is an orally administered molecule that modifies SMN2 pre-mRNA splicing to increase functional SMN protein.

METHODS: SUNFISH Part 1 was a dose-finding study conducted in 51 individuals with types 2 and 3 SMA aged 2-25 years. A dose-escalation method was used to identify the appropriate dose for the subsequent pivotal Part 2. Individuals were randomized (2:1) to risdiplam or placebo at escalating dose levels for a minimum 12-week, double-blind, placebo-controlled period, followed by treatment for 24 months. The dose selection for Part 2 was based on safety, tolerability, pharmacokinetic, and pharmacodynamic data. Exploratory efficacy was also measured.

RESULTS: There was no difference in safety findings for all assessed dose levels. A dose-dependent increase in blood SMN protein was observed; a median twofold increase was obtained within 4 weeks of treatment initiation at the highest dose level. The increase in SMN protein was sustained over 24 months of treatment. Exploratory efficacy showed improvement or stabilization in motor function. The pivotal dose selected for Part 2 was 5 mg for patients with a body weight ≥20 kg or 0.25 mg/kg for patients with a body weight <20 kg.

CONCLUSIONS: SUNFISH Part 1 demonstrated a twofold increase in SMN protein after treatment with risdiplam. The observed safety profile supported the initiation of the pivotal Part 2 study. The long-term efficacy and safety of risdiplam are being assessed with ongoing treatment.

7. Eur J Paediatr Neurol. 2022 Jul;39:1-10. doi: 10.1016/j.ejpn.2022.04.006. Epub 2022 Apr 30.

 Mid- and long-term (at least 12 months) follow-up of patients with spinal muscular atrophy (SMA) treated with nusinersen, onasemnogene abeparvovec, risdiplam or combination therapies: A systematic review of real-world study data.

 Author information:

(1)Austrian Institute for Health Technology Assessment, Vienna, Garnisongasse 7/20, 1090, Austria. Electronic address: Judit.erdos@aihta.at.

 OBJECTIVES: This systematic review aimed to assess mid- and long-term (at least 12 months) real-world study data from all types of spinal muscular atrophy (SMA) patients treated with any of the approved drugs or combination therapies.METHODS: A systematic literature search was carried out in five databases. Two authors selected the studies based on pre-defined selection criteria and independently graded the risk of bias at study level.

RESULTS: Five hundred forty-six records were identified in the literature search and 22 studies (in 26 publications) were included in the analysis. Nusinersen, onasemnogene abeparvovec and combination therapies improved motor endpoints in SMA type 1 patients. SMA type 2 to type 4 patients treated with nusinersen showed stabilisation or small improvements in motor endpoints with some deterioration observed. Quality of life endpoints, such as respiratory and nutritional support were poorly reported on. Drug-related adverse events occurred rarely in all types of SMA patients with all assessed drugs. Mid- and long-term studies on risdiplam could not be identified.

CONCLUSIONS: The large quantity of missing data and heterogeneity of studies hinder comparability. Although stability and further improvement on the long-term is still uncertain, the results from the included evidence, as well as from pivotal trials show a striking contrast to the natural progression of the disease.

8. J Comp Eff Res. 2022 Apr;11(5):347-370. doi: 10.2217/cer-2021-0216. Epub 2022

Jan 18.

 How does risdiplam compare with other treatments for Types 1-3 spinal muscular atrophy: a systematic literature review and indirect treatment comparison.

 Author information:

(1)Global Access, F. Hoffmann-La Roche Ltd, 4070, Basel, Switzerland.

 Aim: To conduct indirect treatment comparisons between risdiplam and other approved treatments for spinal muscular atrophy (SMA). Patients & methods: Individual patient data from risdiplam trials were compared with aggregated data from published studies of nusinersen and onasemnogene abeparvovec, accounting for heterogeneity across studies. Results: In Type 1 SMA, studies of risdiplam and nusinersen included similar populations. Indirect comparison results found improved survival and motor function with risdiplam versus nusinersen. Comparison with onasemnogene abeparvovec in Type 1 SMA and with nusinersen in Types 2/3 SMA was challenging due to substantial differences in study populations; no concrete conclusions could be drawn from the indirect comparison analyses. Conclusion: Indirect comparisons support risdiplam as a superior alternative to nusinersen in Type 1 SMA.

9. Dan Med J. 2020 Aug 7;67(9):A02200100.

 Nusinersen treatment of spinal muscular atrophy - a systematic review.

 INTRODUCTION: 5q spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder caused by insufficient survival motor neuron protein. Untreated SMA involves death or permanent respiratory support (type 1), inability to walk (type 2) or ability to walk (type 3). The incidence of SMA is 1 in 7,500 live births, equivalant to eight children being born with SMA in Denmark annually.

METHODS: We undertook a systematic review of the efficacy of nusinersen as SMA treatment. We included randomised controlled trials and cohort studies. Our primary endpoints were survival without permanent respiratory support and change in motor function.

RESULTS: We identified 658 articles and included 13 of these (two randomised controlled trials and 11 cohort studies). Nusinersen increased survival without permanent respiratory support in SMA type 1 and increased motor function development in types 1-3. Nusinersen treatment before symptom onset in children with presymptomatic SMA produced near-normal motor development. So far, nusinersen has only minor safety concerns mostly related to the lumbar puncture.CONCLUSIONS: Nusinersen increased survival without permanent ventilatory support in children with SMA type 1. Improvements in SMA type 2 and 3 were less evident. Better outcomes were seen in young children with a short disease duration, particularly in children receiving nusinersen before symptom onset. Newborn SMA screening may facilitate presymptomatic treatment with splice modification (nusinersen, risdiplam) or gene implantation therapy (AVXS-101, zolgensma).

10. Br J Clin Pharmacol. 2019 Jan;85(1):181-193. doi: 10.1111/bcp.13786. Epub 2018 Nov 16.

 A phase 1 healthy male volunteer single escalating dose study of the pharmacokinetics and pharmacodynamics of risdiplam (RG7916, RO7034067), a SMN2 splicing modifier.

 Author information:

(1)Roche Innovation Center, Basel, Switzerland.

 AIMS: Risdiplam (RG7916, RO7034067) is an orally administered, centrally and peripherally distributed, survival of motor neuron 2 (SMN2) mRNA splicing modifier for the treatment of spinal muscular atrophy (SMA). The objectives of this entry-into-human study were to assess the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of risdiplam, and the effect of the strong CYP3A inhibitor itraconazole on the PK of risdiplam in healthy male volunteers.

METHODS: Part 1 had a randomized, double-blind, adaptive design with 25 subjects receiving single ascending oral doses of risdiplam (ranging from 0.6-18.0 mg, n = 18) or placebo (n = 7). A Bayesian framework was applied to estimate risdiplam's effect on SMN2 mRNA. The effect of multiple doses of itraconazole on the PK of risdiplam was also assessed using a two-period cross-over design (n = 8).

RESULTS: Risdiplam in the fasted or fed state was well tolerated. Risdiplam exhibited linear PK over the dose range with a multi-phasic decline with a mean terminal half-life of 40-69 h. Food had no relevant effect, and itraconazole had only a minor effect on plasma PK indicating a low fraction of risdiplam metabolized by CYP3A. The highest tested dose of 18.0 mg risdiplam led to approximately 41% (95% confidence interval 27-55%) of the estimated maximum increase in SMN2 mRNA.

CONCLUSIONS: Risdiplam was well tolerated and proof of mechanism was demonstrated by the intended shift in SMN2 splicing towards full-length SMN2 mRNA. Based on these data, Phase 2/3 studies of risdiplam in patients with SMA are now ongoing.