The most-read spinal muscular atrophy (SMA) articles of the year touched on novel SMN1 gene detection, treatment advances, and the diagnostic difficulty encountered by some adult patients with SMA.
The top 5 most-read articles on spinal muscular atrophy (SMA) in 2022 covered advancements in SMN1 detection and SMA treatments, the necessity of early screening, unique diagnostic challenges faced by doctors treating patients with adult presentation of SMA, and more.
Here are the most read SMA articles of 2022.
5. Study: NGS May Be a Superior Method of Detecting SMN1 Gene Copy Number
Detection of the SMN1 gene copy number in patients with SMA and those who might be carriers is important to determine due to the severity of the disease. Next-generation sequencing (NGS) was found to have the best results from among 3 methods, including multiplex ligation probe amplification, and 478 samples. This study, published in Scientific Reports, suggests that NGS can provide a more straightforward way to identify the SMN1 gene copy number.
4. Risdiplam May Be Superior for Certain SMA Type, According to Indirect Comparison
An indirect comparison of 3 SMA treatments was completed, and it found that risdiplam might be a better option than nusinersen in the treatment of type 1 SMA. For this subtype of SMA, a potential link was seen between risdiplam administration and positive event-free survival and overall survival, as well as lower reports of serious adverse events, compared with nusinersen. For SMA types 2 and 3, trial circumstances differed, and the safety and efficacy between risdiplam and nusinersen could not be determined. This study was published in January 2022 online in Journal of Comparative Effectiveness Research.
3. Estonia-Based Study Assesses Prevalence, Characteristics of SMA Diagnoses
A retrospective study conducted in Estonia evaluated data on patients with SMA who received hospital referrals between 1996 and 2020. In that period in Estonia, 53 families saw 57 SMA diagnoses, with a prevalence of 1 case per 8286 births. SMA type 1 was the most prevalent, in 43.9% of patients. A substantial amount of people (96.5%) had homozygous deletion of SMN1. Researchers wanted to use the data as an implementation tool for SMA screening at birth in the country. This study was published by Frontiers in Genetics in early 2022.
2. Mild SMA Poses Diagnostic Difficulties for Clinicians
In adulthood, symptoms of mild phenotype presentations of SMA (type III or IV) can provide neurologists and radiologists with ambiguous information. This article focused on a case report of a 32-year-old woman who presented with slight limb-girdle weakness and heightened fatigue when ascending stairs. Only when electromyography was performed were the researchers prompted to carry out genetic testing, where a targeted SMN1 gene analysis established a 5q SMA. Researchers explained that milder cases of SMA can create incorrect assumptions as to the cause of symptoms. The case report was published in Journal of Neurological Sciences in the summer of 2022.
1. FDA Gives Priority Review to Risdiplam in SMA for Infants Younger Than 2 Months
Risdiplam was approved for children older than 2 months with SMA, and earlier this year the FDA granted priority review of a supplemental new drug application (sNDA) for Evrysdi (risdiplam) to include presymptomatic infants younger than 2 months who have genetically confirmed SMA. At the time of the study, recruitment was still ongoing, but the researchers found that 80% of presymptomatic infants with SMA who received risdiplam for at least 12 months reached major motor milestones, such as rolling and walking independently. This study was published in January 2022 on clinicaltrials.gov.