5qSMA: standardised retrospective natural history assessment in 268 patients with four copies of SMN2

Newborn screening for 5qSMA offers the potential for early, ideally pre-symptomatic, therapeutic intervention. However, limited data exist on the outcomes of individuals with 4 copies of SMN2, and there is no consensus within the SMA treatment community regarding early treatment initiation in this subgroup. To provide evidence-based insights into disease progression, we performed a retrospective analysis of 268 patients with 4 copies of SMN2 from the SMArtCARE registry in Germany, Austria and Switzerland. Inclusion criteria required comprehensive baseline data and diagnosis outside of newborn screening. Only data prior to initiation of disease-modifying treatment were included. The median age at disease onset was 3.0 years, with a mean of 6.4 years. Significantly, 55% of patients experienced symptoms before the age of 36 months. 3% never learned to sit unaided, a further 13% never gained the ability to walk independently and 33% of ambulatory patients lost this ability during the course of the disease. 43% developed scoliosis, 6.3% required non-invasive ventilation and 1.1% required tube feeding. In conclusion, our study, in line with previous observations, highlights the substantial phenotypic heterogeneity in SMA. Importantly, this study provides novel insights: the median age of disease onset in patients with 4 SMN2 copies typically occurs before school age, and in half of the patients even before the age of three years. These findings support a proactive approach, particularly early treatment initiation, in this subset of SMA patients diagnosed pre-symptomatically. However, it is important to recognize that the register will not include asymptomatic individuals.

Clinical Effectiveness of Newborn Screening for Spinal Muscular Atrophy: A Nonrandomized Controlled Trial

Importance

There is increasing evidence that early diagnosis and treatment are key for outcomes in infants with spinal muscular atrophy (SMA), and newborn screening programs have been implemented to detect the disease before onset of symptoms. However, data from controlled studies that reliably confirm the benefits of newborn screening are lacking.

Objective

To compare data obtained on patients with SMA diagnosed through newborn screening and those diagnosed after clinical symptom onset.

Design, Setting, and Participants

This nonrandomized controlled trial used data from the SMARTCARE registry to evaluate all children born between January 2018 and September 2021 with genetically confirmed SMA and up to 3 SMN2 copies. The registry includes data from 70 participating centers in Germany, Austria, and Switzerland. Data analysis was performed in February 2023 so that all patients had a minimal follow-up of 18 months.

Exposure

Patients born in 2 federal states in Germany underwent screening in a newborn screening pilot project. All other patients were diagnosed after clinical symptom onset. All patients received standard care within the same health care system.

Main Outcomes

The primary end point was the achievement of motor milestones.

Results

A total of 234 children (123 [52.6%] female) were identified who met inclusion criteria and were included in the analysis: 44 (18.8%) in the newborn screening cohort and 190 children (81.2%) in the clinical symptom onset cohort. The mean (SD) age at start of treatment with 1 of the approved disease-modifying drugs was 1.3 (2.2) months in the newborn screening cohort and 10.7 (9.1) months in the clinical symptom onset cohort. In the newborn screening cohort, 40 of 44 children (90.9%) gained the ability to sit independently vs 141 of 190 (74.2%) in the clinical symptom onset cohort. For independent ambulation, the ratio was 28 of 40 (63.6%) vs 28 of 190 (14.7%).

Conclusions and Relevance

This nonrandomized controlled trial demonstrated effectiveness of newborn screening for infants with SMA in the real-world setting. Functional outcomes and thus the response to treatment were significantly better in the newborn screening cohort compared to the unscreened clinical symptom onset group.

Trial Registration

German Clinical Trials Register: DRKS00012699.

Long-term efficacy and safety of nusinersen in adults with 5q spinal muscular atrophy: a prospective European multinational observational study

Background

Evidence for the efficacy of nusinersen in adults with 5q-associated spinal muscular atrophy (SMA) has been demonstrated up to a period of 16 months in relatively large cohorts but whereas patients reach a plateau over time is still to be demonstrated. We investigated the efficacy and safety of nusinersen in adults with SMA over 38 months, the longest time period to date in a large cohort of patients from multiple clinical sites.

Methods

Our prospective, observational study included adult patients with SMA from Germany, Switzerland, and Austria (July 2017 to May 2022). All participants had genetically-confirmed, 5q-associated SMA and were treated with nusinersen according to the label. The total Hammersmith Functional Motor Scale Expanded (HFMSE) and Revised Upper Limb Module (RULM) scores, and 6-min walk test (6 MWT; metres), were recorded at baseline and 14, 26, and 38 months after treatment initiation, and pre and post values were compared. Adverse events were also recorded.

Findings

Overall, 389 patients were screened for eligibility and 237 were included. There were significant increases in all outcome measures compared with baseline, including mean HFMSE scores at 14 months (mean difference 1.72 [95% CI 1.19-2.25]), 26 months (1.20 [95% CI 0.48-1.91]), and 38 months (1.52 [95% CI 0.74-2.30]); mean RULM scores at 14 months (mean difference 0.75 [95% CI 0.43-1.07]), 26 months (mean difference 0.65 [95% CI 0.27-1.03]), and 38 months (mean difference 0.72 [95% CI 0.25-1.18]), and 6 MWT at 14 months (mean difference 30.86 m [95% CI 18.34-43.38]), 26 months (mean difference 29.26 m [95% CI 14.87-43.65]), and 38 months (mean difference 32.20 m [95% CI 10.32-54.09]). No new safety signals were identified.

Interpretation

Our prospective, observational, long-term (38 months) data provides further real-world evidence for the continuous efficacy and safety of nusinersen in a large proportion of adult patients with SMA.

Funding

Financial support for the registry from Biogen, Novartis and Roche.

Fenoterol increases erythropoietin concentrations during tocolysis

AIMS

The present study was carried out to assess the effect of the selective beta2-adrenoceptor agonists on erythropoietin (EPO) production.

METHODS

Routine tocolysis with fenoterol (using the regular rate of 2 microg min[-1]) was used as a clinically easily accessible model.

RESULTS

EPO concentrations had doubled 24 h after the start of tocolysis (P < 0.001). This increase lasted over the entire observation period of 48 h. Potassium concentrations fell significantly during the first hours of fenoterol infusion. There was no increase of human placenta lactogen during the period of EPO increase.

CONCLUSIONS

The data confirm our earlier results that fenoterol increases EPO concentrations following haemorrhage. In this model it was not necessary to stimulate EPO production prior to pharmacological treatment.

Organ pattern of age-related changes in the aminoacyl-tRNA synthetase activities of the mouse

The specific activities of 17 aminoacyl-tRNA synthetases from liver, lung, heart, spleen, kidney, small intestine and skeletal muscle of young (2 months) and aged (39 months) female Han:NMRI mice were determined under standard conditions of sample preparation and assay. The average reduction of total activity during ageing is 70% for liver, 50% for lung and spleen, nearly 40% for heart and kidney and nearly 20% for intestine and skeletal muscle. Detailed comparison reveals no general, but an organ-specific pattern. Aminoacyl-tRNA synthetases were, furthermore, found to be ribosome-associated in higher proportions in liver tissue from aged mice.

In vitro effect of asbestos fibers on polymorphonuclear leukocyte function

Incubation of chrysotile and amphibole asbestos fibers with normal human peripheral blood polymorphonuclear leukocytes (PMN) resulted in a significant stimulation of PMN metabolic activity and generation of toxic oxygen by-products as measured by chemiluminescence (CL). Although all asbestos fibers tested were cytotoxic to PMN, cytotoxicity and CL varied disproportionately with fiber type. Anthophyllite asbestos produced the greatest PMN cytotoxicity. It also depressed PMN phagocytosis of latex beads the most and induced the greatest PMN CL response of the fiber types examined. We postulate that asbestos-induced release of toxic oxygen by-products from PMN which have infiltrated into the pulmonary alveoli may contribute to disease pathogenesis in asbestosis.

Asbestos-induced alteration of human peripheral blood monocyte activity

Incubation of chrysotile and anthophyllite asbestos fibers with normal human peripheral blood monocytes resulted in significant suppression of monocyte metabolic activity as measured by chemiluminescence. Both fiber types were cytotoxic to monocytes and depressed monocyte phagocytosis of latex beads. We conclude that asbestos-induced monocyte cytotoxicity could result in release of lysosomal enzymes and/or degradation products which contribute to fibrosis in asbestosis. The depression of phagocytosis and microbicidal function may contribute to the increased incidence of carcinogenesis observed in asbestosis.