Author: Rachael Hansford

Study is first to investigate the neural hallmarks of co-occurring chronic pain and trauma in veterans, finding high, medium, and low symptom groups       

Chronic pain and trauma often co-occur. However, most previous research investigated them in isolation and using subjective measures such as surveys, leading to an incomplete picture. A new study in Frontiers in Pain Research found three unique brain connectivity signatures that appear to indicate veteran susceptibility or resilience to pain and trauma, regardless of their diagnostic or combat history. The study could pave the way for more objective measurements of pain and trauma, leading to targeted and personalised treatments.

Chronic pain and trauma are linked but not studied together

“Chronic pain is a major public health concern, especially among veterans,” said first author Prof Irina Strigo of the San Francisco Veterans Affairs Health Care Center, US. “Moreover, chronic pain sufferers almost never present with a single disorder but often with multiple co-morbidities, such as trauma, posttraumatic stress, and depression.”

Researchers already understand that both pain and trauma can affect connections in our brains, but no-one had studied this in the context of co-occurring trauma and pain. Much pain and trauma research also relies on subjective measurements, such as questionnaires, rather than objective measurements, such as brain scans.

Identifying brain connectivity signatures of pain and trauma

Taking a different approach, the researchers behind this new research studied a group of 57 veterans with both chronic back pain and trauma. The group had quite varied symptoms in terms of pain and trauma severity. By scanning the veterans’ brains using functional magnetic resonance imaging, the researchers identified the strength of connections between brain regions involved in pain and trauma. They then used a statistical technique to automatically group the veterans based on their brain connection signatures, regardless of their self-reported pain and trauma levels.

Based on the veterans’ brain activity, the computer automatically divided them into three groups. Strikingly, these divisions were comparable to the severity of the veterans’ symptoms, and they fell into a low, medium, or high symptom group.

The researchers hypothesised that the pattern of brain connections found in the low symptom group allowed veterans to avoid some of the emotional fallout from pain and trauma, and also included natural pain reduction capabilities. Conversely, the high symptom group demonstrated brain connection patterns that may have increased their chances of anxiety and catastrophising when experiencing pain.

Interestingly, based on self-reported pain and trauma symptoms, the medium symptom group was largely similar to the low symptom group. However, the medium symptom group showed differences in their brain connectivity signature, which suggested that they were better at focusing on other things when experiencing pain, reducing its impact.  

Putting the findings into future practice

“Despite the fact that the majority of subjects within each subgroup had a co-morbid diagnosis of pain and trauma, their brain connections differed,” said Strigo.

“In other words, despite demographic and diagnostic similarities, we found neurobiologically distinct groups with different mechanisms for managing pain and trauma. Neurobiological-based subgroups can provide insights into how these individuals will respond to brain stimulation and psychopharmacological treatments.”

So far, the researchers don’t know whether the neural hallmarks they found represent a vulnerability to trauma and pain or a consequence of these conditions. However, the technique is interesting, as it provides an objective and unbiased hallmark of pain and trauma susceptibility or resilience. It does not rely on subjective measures such as the surveys. In fact, subjective measurements of pain in this study would not differentiate between the low and medium groups.

Techniques that use objective measures, such as brain connectivity, appear more sensitive and could provide a clearer overall picture of someone’s resilience or susceptibility to pain and trauma, thereby guiding personalised treatment and paving the way for new treatments.

Janssen was disappointed with the recent decision (27/5/22) by the National Institute for Health and Care Excellence (NICE) on their Final Appraisal Determination, in which SPRAVATO®▼ (esketamine) nasal spray has not been recommended for use within its marketing authorisation, in combination with a selective serotonin reuptake inhibitor (SSRI) or serotonin and norepinephrine reuptake inhibitor (SNRI), for adults living with treatment-resistant major depressive disorder (TRD), who have not responded to at least two different treatments with antidepressants in the current moderate to severe depressive episode.

• Esketamine nasal spray is the first antidepressant with a new mechanism of action in more than 30 years
• Esketamine nasal spray was authorised for the treatment of adults with treatment-resistant major depressive disorder in Europe in December 2019
• Its novel mechanism of action means it works differently than currently available therapies for major depressive disorder. Esketamine nasal spray is derived from part of the ketamine molecule but is appraised by health authorities as a distinct medication, due to differences in the efficacy and safety profile. As such, it is important these terms are not used interchangeably

“We have worked hard with NICE and other stakeholders throughout the appraisal process to provide the clinical evidence and data to demonstrate esketamine nasal spray is a cost-effective treatment for use on the NHS. Therefore, we are deeply disappointed with the decision published by NICE,” commented Amanda Cunnington, Senior Director of Patient Access, Janssen-Cilag Limited. “In treatment-resistant major depressive disorder, there continues to be systemic issues in introducing innovative treatment options on the NHS, which we have tried to overcome. We remain steadfast in collaborating with stakeholders and are considering all options including an appeal, to enable access to this important treatment for people living with the condition.”

“For the last thirty years we have been waiting for innovations in the field for the most serious and debilitating mental illnesses such as treatment-resistant major depressive disorder,” commented Marjorie Wallace, Chief Executive, SANE. “It is, therefore, a huge disappointment that NICE’s decision will prevent the most desperate patients from accessing esketamine nasal spray.

Sleepio is recommended as a cost saving option for treating insomnia and insomnia symptoms in primary care for people who would otherwise be offered sleep hygiene or sleeping pills.

For people who may be at higher risk of other sleep disorder conditions, such as in pregnancy, or in people with comorbidities, a medical assessment should be done before referral to Sleepio.

More research or data collection is recommended on Sleepio for people who are eligible for face-to-face cognitive behavioural therapy for insomnia (CBT‑I) in primary care. This is because there is limited clinical evidence to show how effective Sleepio is compared with face-to-face CBT‑I. Find out more.

Why NICE made these recommendations

Usual treatment for people with sleep problems is advice about sleep hygiene. Sleeping pills may also be considered if insomnia symptoms are likely to resolve soon. If insomnia symptoms are not likely to resolve soon, best practice is to refer for face-to-face CBT‑I, although its availability in the UK is limited. This clinical pathway is outlined in the British Association for Psychopharmacology (BAP) consensus statement on insomnia. People who may be at higher risk of other sleep disorders including sleep apnoea should have a medical assessment before referral to Sleepio.

Sleepio is a digital self-help programme that includes CBT‑I. It could therefore increase patients’ access to CBT‑I. It also increases the options available to GPs treating insomnia.

Clinical evidence shows that Sleepio reduces insomnia symptoms compared with sleep hygiene and sleeping pills. There is no direct evidence of its effectiveness compared with face-to-face CBT‑I, so further research is recommended in this context.

At a price of £45 per person, Sleepio is cost saving compared with usual treatment in primary care. This is based on an analysis of primary care resource use data before and after Sleepio was introduced in 9 GP practices. Healthcare costs were lower at 1 year, mostly because of fewer GP appointments and sleeping pills prescribed.

PTC Therapeutics, Inc. announced on May 20th that Upstaza™ (eladocagene exuparvovec; PTC-AADC) received a positive opinion by the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA). Once ratified by the European Commission, Upstaza will be the first approved disease-modifying treatment for aromatic L-amino acid decarboxylase (AADC) deficiency for patients 18 months and older and the first marketed gene therapy directly infused into the brain. 

We are thrilled with the positive opinion from the CHMP, and are eager to bring Upstaza to patients living with AADC deficiency.Upstaza will be the first marketed gene therapy that is directly administered into the brain, the first gene therapy approved in a major market in several years, the third gene therapy that is on the market now, and only the fourth in vivo gene therapy ever approved. It’s important for the biotech community to have gene therapy products achieving approvals at regulatory bodies, as well as it being an important milestone for PTC that will help us build the gene therapy franchise and grow our revenue base.

Stuart W. Peltz, Ph.D., Chief Executive Officer, PTC Therapeutics

The CHMP opinion is based on the findings of clinical studies conducted in Taiwan. In addition, data from the compassionate use treatment of patients in Europe were included in the application. In the clinical studies, patients went from no display of any motor milestone development to developing clinically meaningful motor skills and neuromuscular function from as early as three months following treatment, with transformational improvements shown to continue up to nine years after treatment.¹ Cognitive and communication skills improved in all treated patients.^1,2

PTC expects the European Commission to ratify the marketing authorisation for Upstaza under exceptional circumstances in approximately two months. The decision will be applicable to all 27 European Union member states, as well as Iceland, Norway and Liechtenstein. 

About Upstaza™ (eladocagene exuparvovec)

Upstaza, formerly PTC-AADC, is a one-time gene replacement therapy for the treatment of AADC deficiency. It is a recombinant adeno-associated virus serotype 2 (AAV2)-based gene therapy, containing the human DDC gene.¹ It is designed to correct the underlying genetic defect, by delivering a functioning DDC gene directly into the putamen, increasing the AADC enzyme and restoring dopamine production.^2,3

The efficacy and safety profile of Upstaza has been demonstrated across clinical trials and compassionate use programmes.¹ The first patient was dosed more than 10 years ago. In the clinical trials, Upstaza demonstrated transformational neurological improvements, which have continued for up to nine years following treatment. The most common side effects were initial insomnia, irritability and dyskinesia. The full indication proposed by the CHMP for ratification is: Upstaza is indicated for the treatment of patients aged 18 months and older with a clinical, molecular, and genetically confirmed diagnosis of aromatic L‑amino acid decarboxylase (AADC) deficiency with a severe phenotype.

Administration of Upstaza occurs through a stereotactic surgical procedure, a minimally invasive neurosurgical procedure used for the treatment of a number of paediatric and adult neurological disorders. The Upstaza administration procedure will be performed by a qualified neurosurgeon in a centre specialised in stereotactic neurosurgery.

References

¹ Tai CH, et al. Long-term efficacy and safety of eladocagene exuparvovec in patients with AADC deficiency. Mol Ther. 2022;30(2):509-518.

² Chien et al. AGIL-AADC gene therapy results in sustained improvements in motor and developmental milestones through 5 years in children with AADC deficiency. Poster presented at the 48^th Annual Meeting of the Child Neurology Society, Charlotte, NC, USA, Oct 23-26, 2019.

³ Chien YH, et al. Efficacy and safety of AAV2 gene therapy in children with aromatic L-amino acid decarboxylase deficiency: an open-label, phase 1/2 trial. Lancet Child Adolesc Health. 2017;1(4):265-273.

JAMA Neurology publishes Phase 3 study results on the efficacy and safety of FINTEPLA^®▼(fenfluramine) oral solution for the treatment of seizures associated with Lennox-Gastaut Syndrome (LGS)

• Primary endpoint was met demonstrating that fenfluramine, as adjunctive treatment, is effective in significantly reducing the frequency of drop seizures in LGS patients compared to placebo¹
• LGS is a severe childhood-onset developmental and epileptic encephalopathy characterized by drug-resistant seizures with high morbidity² 
• Fenfluramine was recently approved by the U.S. Food and Drug Administration (FDA), as a treatment option for the treatment of seizures associated with LGS, a rare and devastating lifelong childhood-onset epilepsy⁵

UCB, a global biopharmaceutical company, announced on May 2, 2022 the publication in JAMA Neurology of its multi-centre, double-blind, placebo-controlled, parallel-group, randomised Phase 3 trial demonstrating that fenfluramine 0.7 mg/kg/day, when added to a patient’s current anti-epileptic treatment regimen for seizures associated with LGS, is effective in reducing the frequency of drop seizures.¹ Drop seizures cause a person to suddenly lose muscle tone, become limp, and fall to the ground, with a high likelihood of injury.⁶ Within the study, drop seizures were further defined as generalised tonic-clonic (GTC), secondary GTC [focal to bilateral tonic clonic], tonic, atonic, or tonic and atonic.¹

LGS is a severe childhood-onset developmental and epileptic encephalopathy characterised by drug-resistant seizures with high morbidity² as well as serious impairment of neurodevelopmental, cognitive and motor functions.³ LGS has far-reaching effects beyond seizures, including issues with communication, psychiatric symptoms, sleep, behavioral challenges and mobility.⁷ 

The trial met its primary efficacy endpoint. Patients taking fenfluramine 0.7 mg/kg/day experienced an estimated mean difference in the reduction of drop seizure frequency by 19.9% from placebo (P=.001). The median percent reduction in the frequency of drop seizures in the 0.7 mg/kg/day group was 26.5%, compared with 14.2% in the 0.2mg/kg/day group, and 7.6% in patients taking placebo (P=.09). In key secondary outcomes, the trial demonstrated that a greater proportion of patients taking fenfluramine experienced a 50% or greater reduction in drop seizure frequency, compared to patients in the placebo group.¹ 

“Our trial data and the clinical evidence demonstrate the safety and efficacy of fenfluramine for the treatment of seizures associated with LGS and especially for patients where generalised tonic-clonic seizures are the predominant seizure type, where there is a greater risk of mortality,” said Kelly Knupp, M.D., MSCS, FAES, Associate Professor, Children’s Hospital Colorado, Principal Investigator of the study. “LGS is a highly treatment-resistant developmental and epileptic encephalopathy and we need differentiated treatment options, such as fenfluramine, which has a unique mechanism of action different from and complementary to current seizure medications.”

The study also included seizure-type subgroup analyses that demonstrated that fenfluramine 0.7mg/kg/day was highly effective in reducing the frequency of GTCs in nearly 50% of patients. During the maintenance and titration period, patients experienced a decrease in frequency of 45.7% in the fenfluramine 0.7mg/kg/day group, a decrease in frequency of 58.2% in the 0.2 mg/kg/day fenfluramine group, compared with an increase in frequency of 3.7% in the placebo group (P=.001 and P<.001 respectively). The percentage reduction in tonic or atonic seizure frequency was 46.7% in the fenfluramine 0.7mg/kg/day group, compared with 6.8% in the placebo group (P=.046).¹

The reason these data are compelling is because GTCs are commonly observed in patients with LGS.⁹ Moreover, GTCs may result in bodily injury.^10,11 Sudden unexpected death in epilepsy (SUDEP) is a major concern for people living with LGS and patients with a history of GTCs have an estimated 10-fold greater risk of SUDEP.⁴

Fenfluramine was generally well-tolerated in this study. The most common treatment-emergent adverse events included decreased appetite (22%), somnolence (13%), and fatigue (13%).¹ The fenfluramine safety database includes long-term cardiovascular safety data for patients treated for up to three years in DS and LGS.⁵

“This study further validates the importance of fenfluramine as a new treatment option for seizures associated with LGS, including generalised tonic-clonic seizures,” said Mike Davis, Global Head of Epilepsy, UCB. “Through our close connection with the LGS community, we know the challenges they face go beyond treatment resistant seizures to include difficulty with behavior and cognition, and we hope that fenfluramine can provide relief for people living with LGS.” 

Site investigators and caregivers also rated patients as significantly much or very much improved on the Clinical Global Impression of Improvement (CGI-I) scale (investigators 26% vs. 20% vs. 6% and caregivers 34% vs. 27% vs. 5% for 0.7 mg/kg vs. 0.2 mg/kg vs. placebo, respectively).¹ 

Fenfluramine was approved by the U.S. Food and Drug Administration (FDA) for the treatment of LGS in patients aged 2 and older in March 2022.⁵ Fenfluramine was also approved for the treatment of Dravet Syndrome in patients aged 2 and older in June 2020⁵ and by the EU Commission in December 2020 as an add-on treatment for seizures associated with Dravet syndrome in patients aged 2 and older.¹² UCB acquired Zogenix, Inc. and FINTEPLA^® on March 7, 2022.

References

1. Knupp K, Scheffer, I, et al. Efficacy and Safety of Fenfluramine for the Treatment of Seizures Associated with Lennox-Gastaut Syndrome: A Randomized Clinical Study. JAMA Neurology. 2022; E1-E11.
2. Strzelczyk A, Schubert-Bast S. Expanding the Treatment Landscape for Lennox-Gastaut Syndrome: Current and Future Strategies. CNS Drugs. 2021;35(1):61-83. 
3. Arzimanoglou A, French J, Blume WT, et al. Lennox-Gastaut syndrome: a consensus approach on diagnosis, assessment, management, and trial methodology. Lancet Neurol. 2009;8(1):82-93.
4. Sveinsson O, Andersson T, Mattsson P, Carlsson S, Tomson T. Clinical risk factors in SUDEP: A  nationwide population-based case-control study. Neurology. 2020;94(4):e419-e429.
5. FINTEPLA^® (fenfluramine) oral solution CIV. U.S. Prescribing Information. March 2022. Available at : https://zogenix.com/pi/Fintepla-prescribing-information.pdf. Last accessed: April 2022 
6. Mastrangelo M. Lennox-Gastaut Syndrome: A State of the Art Review. Neuropediatrics. 2017;48(3):143-151.
7. LGS Foundation. LGS Characteristics and Major Concerns Survey. https://www.lgsfoundation.org/wp-content/uploads/2021/08/2019-PFDD-Caregiver-Survey-1.pdf. Accessed April 2022.
8. UCB Data on file. Zogenix, Inc. bioStrategies Group. 2021.
9. Cross JH, Auvin S, Falip M, Striano P, Arzimanoglou A. Expert opinion on the management of  Lennox-Gastaut syndrome: treatment algorithms and practical considerations. Front Neurol.  2017;8:505.
10. Gastaut H, Roger J, Soulayrol R, et al. Childhood epileptic encephalopathy with diffuse slow  spike-waves (otherwise known as “petit mal variant”) or Lennox syndrome. Epilepsia. 1966;7(2):139-179.
11. Cross JH, Galer BS, Gil-Nagel A, et al. Impact of fenfluramine on the expected SUDEP mortality  rates in patients with Dravet syndrome. Seizure. 2021;93:154-159.
12. FINTEPLA Summary of Product Characteristics. September 2021. Available at: https://www.ema.europa.eu/en/documents/product-information/fintepla-epar-product-information_en.pdf. Last accessed: April 2022 
13. Zogenix Press Release. Zogenix Submits New Drug Application for FINTEPLA^® (Fenfluramine) in Japan for the Treatment of Epileptic Seizures Associated with Dravet Syndrome. 21 December 2021. Available at: https://www.globenewswire.com/news-release/2021/12/21/2356048/0/en/Zogenix-Submits-New-Drug-Application-for-FINTEPLA-Fenfluramine-in-Japan-for-the-Treatment-of-Epileptic-Seizures-Associated-with-Dravet-Syndrome.html#:~:text=21%2C%202021%20(GLOBE%20NEWSWIRE),fenfluramine)%20for%20the%20treatment%20of. Last accessed: April 2022 
14. Zogenix Press Release. Zogenix Submits Type II Variation Application to the European Medicines Agency (EMA) to Expand the Use of FINTEPLA® (fenfluramine) for the Treatment of Seizures Associated with Lennox-Gastaut Syndrome. 20 December 2021. Available at: https://zogenixinc.gcs-web.com/news-releases/news-release-details/zogenix-submits-type-ii-variation-application-european-medicines. Last accessed: April 2022. 

Please see full Prescribing Information, including Boxed Warning, for additional important information on FINTEPLA.

Refer to the European Summary of Product Characteristics for other adverse reactions and full prescribing information. Date of revision: 04 Nov 2021. 

https://www.ema.europa.eu/en/documents/product-information/fintepla-epar-product-information_en.pdf

▼ This medicinal product is subject to additional monitoring. This will allow quick identification of new safety information. Healthcare professionals are asked to report any suspected adverse reactions. 

ULTOMIRIS^® (ravulizumab-cwvz) Met Primary Endpoint in CHAMPION-NMOSD (Neuromyelitis Optica Spectrum Disorder) Phase III Trial

Positive high-level results from the open-label Phase III CHAMPION-NMOSD trial showed that ULTOMIRIS^®(ravulizumab-cwvz) achieved a statistically significant and clinically meaningful reduction in the risk of relapse in adults with anti-aquaporin-4 (AQP4) antibody-positive (Ab+) neuromyelitis optica spectrum disorder (NMOSD) compared to the external placebo arm from the pivotal SOLIRIS^®PREVENTclinical trial.

ULTOMIRIS, the first and only long-acting C5 complement inhibitor, met the primary endpoint of time to first on-trial relapse, as confirmed by an independent adjudication committee. Notably, no relapse was observed in 58 patients over a median treatment duration of 73 weeks.

NMOSD is a rare and devastating autoimmune disease that affects the central nervous system (CNS), including the spine and optic nerves.^1-3 Most people living with NMOSD often experience unpredictable relapses, a new onset of neurologic symptoms or worsening of existing neurologic symptoms, also referred to as attacks, which tend to be severe and recurrent and may result in permanent disability.^4-6

Every NMOSD relapse can have debilitating and irreversible consequences, so reducing relapses is critical. Patients on ULTOMIRIS remained relapse free over a median treatment duration of 73 weeks in the trial.

Sean J. Pittock, MD, Director of Mayo Clinic’s Center for Multiple Sclerosis and Autoimmune Neurology and of Mayo’s Neuroimmunology Laboratory and lead primary investigator in the CHAMPION-NMOSD trial

Marc Dunoyer, Chief Executive Officer, Alexion, said: “SOLIRISestablished the role of complement inhibition in preventing relapses in NMOSD, and with ULTOMIRIS, we continue to innovate for patients with a more convenient every eight-week dosing schedule. These trial results show that ULTOMIRIS may help patients move towards eliminating relapses, which is an important advancement in the treatment of NMOSD.”

The safety and tolerability of ULTOMIRIS in the Champion-NMOSD trialwere consistent with previous clinical studies and other approved indications. Fifty-six patients are continuing to receive treatment in a long-term extension period, which is ongoing.

The data will be presented and submitted to global health authorities as rapidly as possible to bring forward ULTOMIRIS to the NMOSD community.

References

1. Wingerchuk DM, Lennon VA, Lucchinetti CF, Pittock SJ, Weinshenker BG. The spectrum of neuromyelitis optica. Lancet Neurol. 2007;6(9):805-815.
2. Wingerchuk DM. Diagnosis and treatment of neuromyelitis optica. Neurologist. 2007;13(1):2-11.
3. Hamid SHM, Whittam D, Mutch K et al. What proportion of AQP4-IgG-negative NMO spectrum disorder patients are MOG-IgG positive? A cross sectional study of 132 patients. J Neurol. 2017;264(10):2088-2094.
4. Wingerchuk DM, Weinshenker BG. Neuromyelitis optica. Curr Treat Options Neurol. 2008;10(1):55-66.
5. Kitley J, Leite MI, Nakashima I, et al. Prognostic factors and disease course in aquaporin-4 antibody-positive patients with neuromyelitis optica spectrum disorder from the United Kingdom and Japan. Brain. 2012;135(6):1834-1849.
6. Jarius S, Ruprecht K, Wildemann B, et al. Contrasting disease patterns in seropositive and seronegative neuromyelitis optica: a multicentre study of 175 patients. J Neuroinflamm. 2012;9:14.
7. Wingerchuk DM, Hogancamp WF, O’Brien PC, Weinshenker BG. The clinical course of neuromyelitis optica (Devic’s syndrome). Neurology. 1999;53(5):1107-1114.
8. Papadopoulos MC, Bennett JL, Verkman AS. Treatment of neuromyelitis optica: state-of-the-art and emerging therapies. Nat Rev Neurol. 2014;10(9):493.
9. Cossburn, M., et al. (2012). The Prevalence of Neuromyelitis Optica in South East Wales.” Eur J Neurol., 19(4): 655-659.
10. Takata K, Matsuzaki T, Tajika Y. Aquaporins: water channel proteins of the cell membrane. Prog Histochem Cytochem. 2004;39(1):1-83.
11. Mori M, Kuwabara S, Paul F. Worldwide prevalence of neuromyelitis optica spectrum disorders. J Neurol Neurosurg Psychiatry. 2018 Jun;89(6):555-556. doi: 10.1136/jnnp-2017-317566. Epub 2018 Feb 7. PMID: 29436488.
12. Quek AML, Mckeon A, Lennon VA et al. Effects of age and sex on aquaporin-4 autoimmunity. Arch Neurol 2012 and 69:1039–43.
13. Tüzün E, Kürtüncü M, Türkoğlu R, et al. Enhanced complement consumption in neuromyelitis optica and Behcet’s disease patients. J Neuroimmunol. 2011;233(1-2):211-215.
14. Kuroda H, Fujihara K, Takano R, et al. Increase of complement fragment C5a in cerebrospinal fluid during exacerbation of neuromyelitis optica. J Neuroimmunol. 2013;254(1-2):178-182.
15. Jarius, S., Wildemann, B. (2013). The History of Neuromyelitis Optica. J Neuroinflammation 10, 797.
16. Mealy, M. A., et al. (2019). Assessment of Patients with Neuromyelitis Optica Spectrum Disorder Using the EQ-5D. International journal of MS care, 21(3), 129–134.
17. ClinicalTrials.gov. An Efficacy and Safety Study of Ravulizumab in Adult Participants With NMOSD. NCT Identifier: NCT04201262. Available online. Accessed April 2022.