Successful weaning from mechanical ventilation in a patient with SMA type 1 treated with nusinersen

An algorithm for discontinuing mechanical ventilation in boys with x-linked myotubular myopathy after positive response to gene therapy: the ASPIRO experience

X-linked myotubular myopathy (XLMTM) is a rare, life-threatening congenital myopathy. Most (80%) children with XLMTM have profound muscle weakness and hypotonia at birth resulting in severe respiratory insufficiency, the inability to sit up, stand or walk, and early mortality. At birth, 85-90% of children with XLMTM require mechanical ventilation, with more than half requiring invasive ventilator support. Historically, ventilator-dependent children with neuromuscular-derived respiratory failure of this degree and nature, static or progressive, are not expected to achieve complete independence from mechanical ventilator support. In the ASPIRO clinical trial (NCT03199469), participants receiving a single intravenous dose of an investigational gene therapy (resamirigene bilparvovec) started showing significant improvements in daily hours of ventilation support compared with controls by 24 weeks post-dosing, and 16 of 24 dosed participants achieved ventilator independence between 14 and 97 weeks after dosing. At the time, there was no precedent or published guidance for weaning chronically ventilated children with congenital neuromuscular diseases off mechanical ventilation. When the first ASPIRO participants started showing dramatically improved respiratory function, the investigators initiated efforts to safely wean them off ventilator support, in parallel with primary protocol respiratory outcome measures. A group of experts in respiratory care and physiology and management of children with XLMTM developed an algorithm to safely wean children in the ASPIRO trial off mechanical ventilation as their respiratory muscle strength increased. The algorithm developed for this trial provides recommendations for assessing weaning readiness, a stepwise approach to weaning, and monitoring of children during and after the weaning process.

The socioeconomic burden of spinal muscular atrophy in Saudi Arabia: a cross-sectional pilot study

Background

Spinal muscular atrophy (SMA) is a rare debilitating condition with a significant burden for patients and society. However, little is known about how it affects Saudi Arabia's population. The socioeconomic and medical characteristics of affected SMA patients and their caregivers are lacking.

Purpose

This study aimed to describe the socioeconomic and medical characteristics of SMA patients and caregivers in Saudi Arabia.

Patients and methods

A cross-sectional questionnaire-based study was conducted using snowball sampling. Assessment tools including EuroQol (EQ-5D-5L) and visual analog scale (EQ-VAS), Generalized Anxiety Disorder 7-item (GAD-7), Patient Health Questionnaire (PHQ-9), and Costs for Patients Questionnaire (CoPaQ) were used to assess the quality of life (QoL), anxiety, depression, and out-of-pocket expenditures.

Results

Sixty-four caregivers of SMA patients participated. Type I patients had higher sibling concordance, ICU hospitalization, and mechanical support needs. Type III patients had better QoL. Type I patients' caregivers had higher depression scores. Type III patients' caregivers had higher out-of-pocket expenditures. Forty-eight percent received supportive care, while others received SMA approved therapies.

Conclusion

SMA imposes a significant socioeconomic burden on patients and caregivers, requiring more attention from the healthcare system. Access to innovative therapies varied across SMA types. Pre-marital screening and early detection are crucial to reduce disease incidence and ensure timely treatment.

Successful weaning from the invasive respiratory support after nusinersen treatment in a child with SMA type 1: A case report

BACKGROUND

Spinal muscular atrophy (SMA) is an autosomal recessive disease, which can be classified into 4 types according to the symptom onset age and the highest physical developmental milestone. Among them, type 1 SMA is the most severe form that affects infants younger than 6 months. Permanent assisted ventilation is usually needed for infants with type 1 SMA before the age of 2 years due to the rapid progression of disease. Nusinersen can improve the motor function of SMA patients, but its effect on respiratory function varies. In the present study, we reported a case of child with type 1 SMA who was successfully weaned from the invasive respiratory support after nusinersen treatment.

CASE PRESENTATION

A girl aged 6 years and 5 months was admitted for SMA in the Children's Hospital of Nanjing Medical University for 18 times. She received the first administration of nusinersen in November 2020 at the age of 5 years and 1 month. At the age of 6 years and 1 month following 6 loading doses, we tried to wean the child from the invasive ventilation for non-invasive respiratory support using a nasal mask. At present, the patient shows oxygen saturation (SpO₂) above 95% without ventilator support during the daytime, and no signs of dyspnea. A non-invasive home ventilator was used at nighttime for the sake of safety. The CHOP INTEND score increased by 11 points from the first loading dose to the sixth. She can now move her limbs against gravity, take in food orally and perform partial vocal function.

CONCLUSIONS

We reported a child with type 1 SMA who was successfully weaned from the 2-years invasive ventilation after 6 loading doses, and now only need non-invasive ventilation 12 h per day. It is suggested that even a late nusinersen treatment can improve respiratory and motor function in SMA patients, and wean them from mechanical ventilation, thus improve the quality of life and reduce the medical cost.

The effects of nusinersen treatment on respiratory status of children with spinal muscular atrophy

BACKGROUND

Respiratory involvement is the main factor predicting the prognosis of spinal muscular atrophy (SMA). Significant responses in motor functions have been demonstrated with nusinersen, but pulmonary outcomes are still varied. We aimed to explore the effects of nusinersen on the respiratory functions of patients with SMA.

METHODS

Patients with SMA who were receiving regular nusinersen treatment in our tertiary care hospital were enrolled in this study. We evaluated the patients in terms of the necessity to ventilatory or nutritional support, presence of motor involvement and other comorbidities related with prognosis at three consecutive assessments.

RESULTS

The study group consisted of 43 patients (18 type 1, 12 type 2, and 13 type 3) with SMA with a mean age of 27.8 months at diagnosis and 60.8 months at the beginning of nusinersen treatment. The respiratory function improvements were noted in six patients at third assessment. Early initiation of nusinersen was significantly correlated with reduced hospital admissions (P = 0.026). Nutritional support and weight gain were remarkable in the ventilatory-supported group. Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders scores were significantly higher in the non-tracheostomized group in patients with SMA type 1 (P < 0.005).

CONCLUSIONS

We posit that nusinersen may change the natural prognosis of SMA and improve care of children with SMA. Following up children with SMA for longer periods under nusinersen may be beneficial for understanding the effects of treatment. Results of our study need to be supported by future long-term studies to reach a consensus on nusinersen, considering the overall genetic and environmental status as well as the cost-effectiveness of the treatment.