Newborn screening for spinal muscular atrophy: The views of affected families and adults

Parental Experiences with Newborn Screening and Gene Replacement Therapy for Spinal Muscular Atrophy

BACKGROUND

Spinal muscular atrophy (SMA) is a genetic neurodegenerative disorder with onset predominantly in infants and children. In recent years, newborn screening and three treatments, including gene replacement therapy (Onasemnogene abeparvovec-xioi), have become available in the United States, aiding in the diagnosis and treatment of children with SMA.

OBJECTIVE

To evaluate parents' experiences with newborn screening and gene replacement therapy and to explore best practices for positive newborn screen disclosure and counseling of families.

METHODS

We conducted semi-structured interviews (n = 32) and online surveys (n = 79) of parents whose children were diagnosed with SMA (on newborn screening or symptomatically) and treated with gene replacement therapy.

RESULTS

Gene replacement therapy was most parents' first treatment choice, although concerns regarding long term efficacy (65%) and safety (51%) were common. Information provided during the newborn screening disclosure was quite variable. Only 34% of parents reported the information provided was sufficient and expressed need for more information about treatment. Although many parents experienced denial of the diagnosis at initial disclosure, 94% were in favor of inclusion of SMA on newborn screening. Parents were almost universally anxious following diagnosis and over half remained anxious at the time of study participation with uncertainty of the future being a key concern. Many parents had difficulty processing information provided during their first clinic appointment due to its complexity and their emotional state at the time.

CONCLUSIONS

Utilizing this data, we provide a recommendation for the information provided in newborn screening disclosure, propose adjustments to education and counseling during the first clinic visit, and bring awareness of parents' mental health difficulties.

Parent Perceptions in Choosing Treatment for Infants With Spinal Muscular Atrophy Diagnosed Through Newborn Screening

OBJECTIVE

To identify factors parents considered in treatment decision making for children diagnosed with spinal muscular atrophy on newborn screening.

METHODS

Participants were recruited through the University of Rochester or through flyers and Cure SMA social media outreach and asked to complete a telephone or online survey. Data were analyzed through mixed methods using descriptive statistics and theme identification in narrative responses.

RESULTS

Eighteen parents with children diagnosed with spinal muscular atrophy on newborn screening participated. Thirteen of 18 chose onasemnogene abeparvovec, 2 of 18 chose risdiplam, 1 of 18 chose nusinersen, and 2 of 18 did not receive treatment. The most commonly reported factors impacting treatment choice included treatment frequency and administration method. Seventeen (94.4%) parents felt that inclusion of spinal muscular atrophy on newborn screening was positive because it could allow for better outcomes with earlier treatment.

CONCLUSION

Treatment frequency and administration method were the most important factors for parents in determining spinal muscular atrophy treatment. Parents felt positively about newborn screening due to opportunity for earlier treatment.

Select Ethical Aspects of Next-Generation Sequencing Tests for Newborn Screening and Diagnostic Evaluation of Critically Ill Newborns

In this review, we analyze medical and select ethical aspects of the increasing use of next-generation sequencing (NGS) based tests in newborn medicine. In the last five years, there have been several studies exploring the role of rapid exome sequencing (ES) and genome sequencing (GS) in critically ill newborns. While the advantages include a high diagnostic yield with potential changes in interventions, there have been ethical dilemmas surrounding consent, information about adult-onset diseases and resolution of variants of uncertain significance. Another active area of research includes a cohort of studies funded under Newborn Sequencing in Genomic Medicine and Public Health pertaining to the use of ES and GS in newborn screening (NBS). While these techniques may allow for screening for several genetic disorders that do not have a detectable biochemical marker, the high costs and long turnaround times of these tests are barriers in their utilization as public health screening tests. Discordant results between conventional NBS and ES-based NBS, as well as challenges with consent, are other potential pitfalls of this approach. Please see the Bush, Al-Hertani and Bodamer article in this Special Issue for the broader scope and further discussion.

Infants Diagnosed with Spinal Muscular Atrophy and 4 SMN2 Copies through Newborn Screening - Opportunity or Burden?

Although the value of newborn screening (NBS) for early detection and treatment opportunity in SMA patients is generally accepted, there is still an ongoing discussion about the best strategy in children with 4 and more copies of the SMN2 gene. This gene is known to be the most important but not the only disease modifier.

In our SMA-NBS pilot project in Germany comprising 278,970 infants screened between January 2018 and November 2019 were 38 positive cases with a homozygous SMN1 deletion. 40% of them had 4 or more SMN2 copies. The incidence for homozygous SMN1 deletion was 1 : 7350, which is within the known range of SMA incidence in Germany.

Of the 15 SMA children with 4 SMN2 copies, one child developed physical signs of SMA by the age of 8 months. Reanalysis of the SMN2 copy number by a different test method revealed 3 copies. Two children had affected siblings with SMA Type III, who were diagnosed only after detection of the index patient in the NBS. One had a positive family history with an affected aunt (onset of disease at the age of 3 years). Three families were lost to medical follow up; two because of socioeconomic reasons and one to avoid the psychological stress associated with the appointments.

Decisions on how to handle patients with 4 SMN2 copies are discussed in the light of the experience gathered from our NBS pilot SMA program.

Parental experiences of a diagnosis of neonatal diabetes and perceptions of newborn screening for glucose: a qualitative study

Neonatal diabetes presents <6 months of life but delays in recognition result in presentation with life-threatening hyperglycaemia/diabetic ketoacidosis. Early identification and rapid genetic diagnosis is crucial and ensures correct treatment/management. Adding 'glucose' to newborn bloodspot screening (NBS) could aid prompt detection but requires evidence of parental acceptance.

OBJECTIVES

Increase understanding of parental experience of presentation/recognition of neonatal diabetes and perceptions of glucose testing within NBS.

SETTING

UK families confirmed with a genetic diagnosis of neonatal diabetes, November 2014-2018, were invited to participate.

PARTICIPANTS

In-depth qualitative interviews were conducted with 10 parents of 14 children. 8 had transient neonatal diabetes: KCNJ11 (n=5), ABCC8 (n=1), 6q24 (n=2), 6 had permanent neonatal diabetes: KCNJ11 (n=4), INS (n=1), homozygous GCK (n=1).

PRIMARY AND SECONDARY OUTCOME MEASURES

Interviews audio recorded, transcribed and subjected to thematic content analysis.

RESULTS

3 key themes emerged:Babies were extremely ill at hospital admission, with extended stays in intensive care required.Identification of diabetes was not 'standardised' and perceived a 'chance' finding.Adding glucose to NBS was universally considered extremely positive.

CONCLUSIONS

Diagnosis of neonatal diabetes is frequently delayed, resulting in critically ill presentation with prolonged intensive care support, additional healthcare costs and familial distress. Potential to detect hyperglycaemia earlier was universally endorsed by parents with no negative consequences identified. Although further study including a larger number of individuals is needed to confirm our findings this study provides the first evidence of acceptability of glucose testing fulfilling Wilson-Jungner criteria for implementation within the NBS programme.

Teaching an old drug new tricks: repositioning strategies for spinal muscular atrophy

Spinal muscular atrophy (SMA) is a childhood disorder caused by loss of the SMN gene. Pathological hallmarks are spinal cord motor neuron death, neuromuscular junction dysfunction and muscle atrophy. The first SMN genetic therapy was recently approved and other SMN-dependent treatments are not far behind. However, not all SMA patients will reap their maximal benefit due to limited accessibility, high costs and differential effects depending on timing of administration and disease severity. The repurposing of commercially available drugs is an interesting strategy to ensure more rapid and less expensive access to new treatments. In this mini-review, we will discuss the potential and relevance of repositioning drugs currently used for neurodegenerative, neuromuscular and muscle disorders for SMA.

Perspectives in genetic counseling for spinal muscular atrophy in the new therapeutic era: early pre-symptomatic intervention and test in minors

Spinal muscular atrophy (SMA) is an autosomal-recessive neuromuscular disorder representing a continuous spectrum of muscular weakness ranging from compromised neonates to adults with minimal manifestations. Patients show homozygous absence or disease-causing variants of the SMN1 gene (−/− or 0/0) and in carriers only one copy is absent or mutated (1/0). Genetic diagnosis and counseling in SMA present several challenges, including the existence of carriers (2/0) that are undistinguishable of non-carriers (1/1) with current genetic testing methods and the report of patients (0/0) with very mild manifestations and even asymptomatic that are discovered when a full symptomatic case appears in the family. Younger asymptomatic siblings of symptomatic SMA patients are usually never tested until adolescence or adult life. However, following regulatory approval of the first tailored treatment for SMA, the prospects for care of these patients have changed. Early testing, including pre-symptomatic newborn screening and confirmation of diagnosis would change proactive measures and opportunities for therapy based in the actual landscape of new treatments. This review discusses the challenges and new perspectives of genetic counseling in SMA.

Newborn screening for haemophilia: The views of families and adults living with haemophilia in the UK

INTRODUCTION

As genomic sequencing become more efficient and cost-effective, the number of conditions identified through newborn screening globally is set to dramatically increase. Haemophilia is a candidate condition; however, very little is known about the attitudes of the haemophilia community towards screening.

AIM

This study aimed to outline the perspectives of adults with haemophilia and their families towards newborn screening.

METHODS

A paper and online survey on screening were distributed to every family known to the Haemophilia Society UK. Data collection occurred between January and June 2018. In total, 327 participants completed the survey: 76% were a relative of a person with haemophilia and 24% had haemophilia themselves; 83% were living with haemophilia A and 17% with haemophilia B.

RESULTS

The vast majority supported newborn screening (77%) and preferred it to other forms of screening (preconception or prenatal). Participants supported newborn screening primarily because they viewed it as a means to facilitate early support and treatment, facilitate informed decisions about future pregnancies and prevent the "diagnostic odyssey." The 23% who did not support the screen did not associate these particular benefits with newborn screening.

CONCLUSION

Haemophilia emerged from this analysis as a condition that the vast majority of participants considered a "liveable" disability and one best suited to newborn screening programmes that could improve support to affected families rather than reduce the birth rate of affected children.

Nusinersen treatment of spinal muscular atrophy: current knowledge and existing gaps

Spinal muscular atrophy (SMA) is a recessive disorder caused by a mutation in the survival motor neuron 1 gene (SMN1); it affects 1 in 11 000 newborn infants. The most severe and most common form, type 1 SMA, is associated with early mortality in most cases and severe disability in survivors. Nusinersen, an antisense oligonucleotide, promotes production of full-length protein from the pseudogene SMN2. Nusinersen treatment prolongs survival of patients with type 1 SMA and allows motor milestone acquisition. Patients with type 2 SMA also show progress on different motor scales after nusinersen treatment. Nusinersen was recently approved by the European Medicines Agency and the US Food and Drug Administration; it is now reimbursed in several European countries and in the USA. In Australia, the transition from expanded access programme to commercial availability is coming soon. In New Zealand, an expanded access programme is opened, and in Canada price negotiation for the treatment is in progress. In this review we exemplify the clinical benefit of nusinersen in subgroups of patients with SMA. Nusinersen represents the first efficacious marked approved drug in type 1 and type 2 SMA. Different knowledge gaps, such as results in older patients, in patients with permanent ventilation, in patients with neonatal forms, or in patients after spinal fusion, still need to be addressed. WHAT THIS PAPER ADDS: Identifies gaps in knowledge about the efficacy of nusinersen in broader populations of patients with spinal muscular atrophy. Identifies open questions in populations of patients where proof of efficacy is available.

Combien de patients atteints de SMA en France ?

L’épidémiologie des amyotrophies spinales infantiles (ASI ou SMA pour spinal muscular atrophy) reste à faire en France. Bien qu’appartenant aux maladies rares, elle n’en est pas moins fréquente parmi les maladies génétiques de l’enfant. En l’absence d’un registre ou d’une banque de données vraiment opérationnels, les différents acteurs concernés par la SMA sont condamnés à se référer aux seules données de la littérature internationale. À l’heure où le comptage des individus pouvant potentiellement bénéficier de thérapies innovantes comme le nusinersen devient un enjeu crucial, notamment pour les autorités de santé, la filière de santé neuromusculaire Filnemus a pris l’initiative de contribuer à cet inventaire, à l’aide de son réseau de centres de compétence et de référence. À cet effet, deux enquêtes, de portée et de méthodologie distinctes, ont été réalisées ces derniers mois.

Spinal muscular atrophy type I and the dual role of viruses: An interview with Professor Basil T. Darras, Professor of Neurology (Pediatrics) at Harvard Medical School

According to Professor Basil T. Darras, Professor of Neurology (Pediatrics) at Harvard Medical School and Director of the Spinal Muscular Atrophy (SMA) Program at Boston Children's Hospital in Boston (MA, USA), the diagnosis of SMA type I is clinical and is based on detailed general physical and neurological examinations. SMA type I remains the most common genetic disease resulting in death in infancy and is really devastating for the child, the parents, as well as the medical professionals with the privilege of caring for patients with SMA and their parents. The proposed management options include: i) no respiratory support; ii) non-invasive ventilation; and iii) tracheotomy with mechanical ventilation. Deciding, which option is the best, is indeed a very personal decision. The optimal clinical care should be extremely mindful of parents' wishes and management goals with regard to the quality of life. Since the end of 2016 in the USA, and recently in Europe, there exists the possibility of accessing a novel treatment drug for SMA, namely Nusinersen. This antisense oligonucleotide is administered intrathecally and increases the production of the fully functional SMN protein, thus improving motor function, the quality of life and survival. Among the ongoing clinical trials, oral treatment with RG7916, a small molecule SMN2 splicing modifier, appears to be really promising. Gene therapy using viral vectors is expected to offer an 'one and done' therapy and possibly a cure, if administered early in life, before any symptoms appear. It is really interesting that viruses, which at the moment are the cause of death of children with SMA, if genetically modified, may be used for their treatment.

Newborn genetic screening for spinal muscular atrophy in the UK: The views of the general population

Background

Spinal muscular atrophy (SMA) is an inherited neuromuscular disorder and a leading genetic cause of infant death worldwide. However, there is no routine screening program for SMA in the UK. Lack of treatments and the inability of screening tests to accurately predict disease severity are among the key reasons implementation of screening has faltered in the UK. With the recent release of the first therapy for SMA (Nusinersen), calls are being made for a reconsideration of this stance; however, very little is known about the views of the general public.

Methods

An online survey was administered to 232 individuals with no prior relationship with SMA to assess their attitudes toward a newborn screening program for it. Results are compared with previously gathered data on the views of SMA‐affected families toward screening.

Results

Eighty‐four percent of participants were in favor of newborn screening. Key reasons for support were a belief that it would lead to better healthcare and life expectancy for affected infants and facilitate informed decision‐making for future pregnancies. Key reasons for nonsupport were a belief in the potential for significant negative impact on the family unit in terms of bonding and stress.

Conclusions

Public acceptability is a key component in the evaluation of any potential screening program in the UK. This study demonstrates that newborn screening for SMA is viewed largely positively by people unfamiliar with the condition. The importance of early identification overrode all other social and ethical concerns about screening for the majority of participants.

The role of experiential knowledge within attitudes towards genetic carrier screening: A comparison of people with and without experience of spinal muscular atrophy

Purpose

Autosomal recessive conditions, while individually rare, are a significant health burden with limited treatment options. Population carrier screening has been suggested as a means of tackling them. Little is known, however, about the attitudes of the general public towards such carrier screening and still less about the views of people living with candidate genetic diseases. Here, we focus on the role that such experience has on screening attitudes by comparing views towards screening of people with and without prior experience of the monogenetic disorder, Spinal Muscular Atrophy.

Methods

An exploratory sequential mixed methods design was adopted. In‐depth qualitative interviews were used to develop two surveys. The surveys addressed attitudes towards carrier screening (pre‐conceptual and prenatal) for SMA.

Participants

337 participants with SMA experience completed the SMA Screening Survey (UK) and 336 participants with no prior experience of SMA completed the UK GenPop Survey, an amended version of the SMA Screening Survey (UK).

Results

The majority of both cohorts were in favour of pre‐conception and prenatal carrier screening, however people with experience of type II SMA were least likely to support either. Key differences emerged around perceptions of SMA, with those without SMA experience taking a dimmer view of the condition than those with.

Conclusion

This study underscores the significance of prior experience with the condition to screening attitudes. It highlights the need for accurate and high‐quality educational resources to support any future carrier screening programmes, that particularly in relation to rare genetic disorders like SMA that will fall outside the remit of everyday experience for the majority of the population.

Newborn screening for spinal muscular atrophy: The views of affected families and adults

Spinal muscular atrophy (SMA) is one of the leading genetic causes of infant death worldwide. However, due to a lack of treatments, SMA has historically fallen short of Wilson‐Jungner criteria. While studies have explored the acceptability of expanded newborn screening to the general public, the views of affected families have been largely overlooked. This is in spite of the potential for direct impacts on them and their unique positioning to consider the value of early diagnosis. We have previously reported data on attitudes toward pre‐conception and prenatal genetic screening for SMA among affected families (adults with SMA [n = 82] and family members [n = 255]). Here, using qualitative interview [n = 36] and survey data [n = 337], we report the views of this same cohort toward newborn screening. The majority (70%) of participants were in favor, however, all subgroups (except adults with type II) preferred pre‐conception and/or prenatal screening to newborn screening. Key reasons for newborn screening support were: (1) the potential for improved support; (2) the possibility of enrolling pre‐symptomatic children on clinical trials. Key reasons for non‐support were: (1) concerns about impact on the early experiences of the family; (2) inability to treat. Importantly, participants did not view the potential for inaccurate typing as a significant obstacle to the launch of a population‐wide screening program. This study underscores the need to include families affected by genetic diseases within consultations on screening. This is particularly important for conditions such as SMA which challenge traditional screening criteria, and for which new therapeutics are emerging.