Long-term safety of satralizumab in neuromyelitis optica spectrum disorder (NMOSD) from SAkuraSky and SAkuraStar

Real-world management of patients with neuromyelitis optica spectrum disorder using satralizumab: Results from a Japanese claims database

BACKGROUND

Satralizumab, a humanized anti-interleukin-6 receptor monoclonal antibody, has been approved globally for the treatment of neuromyelitis optica spectrum disorder (NMOSD), based on positive results from two randomized, double-blind, phase 3 studies: SAkuraSky (NCT02028884) and SAkuraStar (NCT02073279). There remains an unmet need to understand the real-world management of NMOSD, especially in patients undergoing tapering of concomitant therapy. We examined real-world treatment patterns, including concomitant glucocorticoids and immunosuppressants, and relapse in satralizumab-treated patients with NMOSD, using a Japanese administrative hospital claims database.

METHODS

We used retrospective data from the Medical Data Vision hospital-based administrative claims database. The index date was the date of first satralizumab prescription and the study period was set between August 2018 and March 2022. Patients were included in the overall population if they had a first prescription for satralizumab between August 2020 and March 2022, an International Classification of Disease, Version10 code of G36.0 prior to March 2022, and were observable for ≥90 days prior to the index date. The primary endpoint was the percentage of patients with relapse-free reduction of oral glucocorticoids to 0 mg/day at 360 days of continued satralizumab treatment. Secondary endpoints included time to relapse, number of relapses after the index date while being on continuous satralizumab treatment, annualized relapse rate before and after the index date, and concomitant medication use. Relapse and dose reduction were identified using definition specifically developed for this study.

RESULTS

Of the 131 patients included in the overall population, most were female (90.8 %), aged 18-65 years (75.6 %), and were prescribed oral glucocorticoids (93.1 %). Azathioprine (19.1 %) and tacrolimus, a calcineurin inhibitor (18.3 %), were the most common immunosuppressants at index date. Six (4.6 %) patients had a history of biologic use (tocilizumab, 1 [0.8 %]; eculizumab, 5 [3.8 %]). Among 111 patients observable for 360 days pre-index, there were 0.6 ± 0.8 (mean ± SD) relapses during 360 days before the index date. The median (interquartile range) duration of satralizumab exposure was 197.0 (57.0-351.0) days. Most (125/131; 95.4 %) patients were relapse-free post-index; 6 (4.6 %) patients relapsed within 90 days after the index date, of which 2 had the first relapse within 7 days after the index date. Among 21 patients with 360-day follow-up, 6 (28.6 %) patients were on 0 mg/day dose of glucocorticoid prescription without relapse 360 days post-index. Of these 6 patients, 2 had no prescription of oral glucocorticoids at the index date and remained glucocorticoid- and relapse-free 360 days after the index date.

CONCLUSION

These real-world data support the phase 3 clinical trials. Our results, over a median duration of satralizumab exposure of 197.0 days, showed that a majority (125/131, 95.4 %) of patients were relapse-free after initiating satralizumab treatment. The number of glucocorticoid-free patients without relapse increased over time under continuous satralizumab prescription. Further studies are needed to confirm if satralizumab can be used as a potential immunosuppressant- and glucocorticoid-sparing agent.

Updates in NMOSD and MOGAD Diagnosis and Treatment: A Tale of Two Central Nervous System Autoimmune Inflammatory Disorders

Aquaporin-4-IgG positive neuromyelitis optica spectrum disorder (AQP4+NMOSD) and myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD) are antibody-associated diseases targeting astrocytes and oligodendrocytes, respectively. Their recognition as distinct entities has led to each having its own diagnostic criteria that require a combination of clinical, serologic, and MRI features. The therapeutic approach to acute attacks in AQP4+NMOSD and MOGAD is similar. There is now class 1 evidence to support attack-prevention medications for AQP4+NMOSD. MOGAD lacks proven treatments although clinical trials are now underway. In this review, we will outline similarities and differences between AQP4+NMOSD and MOGAD in terms of diagnosis and treatment.

Advances in the long-term treatment of neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune neuroinflammatory disorder with a prevalence of 1-5/100,000 globally, characterized by attacks of the central nervous system including but not limited to optic neuritis, transverse myelitis and brainstem lesions, including area postrema lesions. These autoimmune attacks can lead to irreversible damage if left untreated, therefore strategies have been developed to prevent relapses. Initial off-label treatments have achieved variable levels of success in relapse prevention, but improved relapse prevention and quality of life remain a goal in the field. A better understanding of the underlying pathophysiology of NMOSD over the last 10 years has led to newer, more specific approaches in treatment, culminating in the first FDA approved treatments in the disease. In this review, we will discuss the seminal trials of PREVENT or Eculizumab in the treatment of aquaporin-4 (AQP4)-IgG positive NMOSD, N-Momentum or Inebilizumab in the study of NMOSD (both AQP4-IgG positive and negative) and SAkura Sky and SAkuraStar which studied satralizumab in AQP4-IgG seropositive and seronegative NMOSD patients. We will also discuss the extension trials of each of these medications and what lead to their approval in AQP4-IgG seropositive NMOSD patients. We will then examine treatments in the pipeline for adult and pediatric NMOSD patients and conclude with discussions on treatment considerations in pregnant patients and how to approach treatment of NMOSD patients during COVID.

Monoclonal antibody therapies for aquaporin-4-immunoglobulin G-positive neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody-associated disease

Monoclonal antibody therapies mark the new era of targeted treatment for relapse prevention in aquaporin-4 (AQP4)-immunoglobulin G (IgG)-positive neuromyelitis optica spectrum disorder (AQP4-IgG+NMOSD). For over a decade, rituximab, an anti-CD20 B-cell-depleting agent, had been the most effectiveness treatment for AQP4-IgG+NMOSD. Tocilizumab, an anti-interleukin-6 receptor, was also observed to be effective. In 2019, several randomized, placebo-controlled trials were completed that demonstrated the remarkable efficacy of eculizumab (anti-C5 complement inhibitor), inebilizumab (anti-CD19 B-cell-depleting agent), and satralizumab (anti-interleukin-6 receptor), leading to the Food and Drug Administration (FDA) approval of specific treatments for AQP4-IgG+NMOSD for the first time. Most recently, ravulizumab (anti-C5 complement inhibitor) was also shown to be highly efficacious in an open-label, external-controlled trial. Although only some patients with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) warrant immunotherapy, there is currently no FDA-approved treatment for relapse prevention in MOGAD. Observational studies showed that tocilizumab was associated with a decrease in relapses, whereas rituximab seemed to have less robust effectiveness in MOGAD compared to AQP4-IgG+NMOSD. Herein, we review the evidence on the efficacy and safety of each monoclonal antibody therapy used in AQP4-IgG+NMOSD and MOGAD, including special considerations in children and women of childbearing potential.

Monoclonal antibodies in neuro-ophthalmology

Neuro-ophthalmologic diseases include a broad range of disorders affecting the afferent and efferent visual pathways. Recently, monoclonal antibody (mAb) therapies have emerged as a promising targeted approach in the management of several of these complex conditions. Here, we describe the mechanism-specific applications and advancements in neuro-ophthalmologic mAb therapies. The application of mAbs in neuro-ophthalmologic diseases highlights our increasing understanding of disease-specific mechanisms in autoimmune conditions such as neuromyelitis optica, thyroid eye disease, and myasthenia gravis. Due to the specificity of mAb therapies, applications in neuro-ophthalmologic diseases have yielded exceptional clinical outcomes, including both reduced rate of relapse and progression to disability, visual function preservation, and quality of life improvement. These advancements have not only expanded the range of treatable neuro-ophthalmologic diseases but also reduced adverse events and increased the response rate to treatment. Further research into neuro-ophthalmologic disease mechanisms will provide accurate and specific targeting of important disease mediators through applications of future mAbs. As our understanding of these diseases and the relevant therapeutic targets evolve, we will continue to build on our understanding of how mAbs interfere with disease pathogenesis, and how these changes improve clinical outcomes and quality of life for patients.

Update on the diagnosis and treatment of neuromyelitis optica spectrum disorders (NMOSD) - revised recommendations of the Neuromyelitis Optica Study Group (NEMOS). Part II: Attack therapy and long-term management

This manuscript presents practical recommendations for managing acute attacks and implementing preventive immunotherapies for neuromyelitis optica spectrum disorders (NMOSD), a rare autoimmune disease that causes severe inflammation in the central nervous system (CNS), primarily affecting the optic nerves, spinal cord, and brainstem. The pillars of NMOSD therapy are attack treatment and attack prevention to minimize the accrual of neurological disability. Aquaporin-4 immunoglobulin G antibodies (AQP4-IgG) are a diagnostic marker of the disease and play a significant role in its pathogenicity. Recent advances in understanding NMOSD have led to the development of new therapies and the completion of randomized controlled trials. Four preventive immunotherapies have now been approved for AQP4-IgG-positive NMOSD in many regions of the world: eculizumab, ravulizumab - most recently-, inebilizumab, and satralizumab. These new drugs may potentially substitute rituximab and classical immunosuppressive therapies, which were as yet the mainstay of treatment for both, AQP4-IgG-positive and -negative NMOSD. Here, the Neuromyelitis Optica Study Group (NEMOS) provides an overview of the current state of knowledge on NMOSD treatments and offers statements and practical recommendations on the therapy management and use of all available immunotherapies for this disease. Unmet needs and AQP4-IgG-negative NMOSD are also discussed. The recommendations were developed using a Delphi-based consensus method among the core author group and at expert discussions at NEMOS meetings.

Urosepsis Risk in Neuromyelitis Optica Spectrum Disorder Patients Administered Satralizumab

Objective The interleukin-6 (IL-6) inhibitor satralizumab is an established treatment for neuromyelitis optica spectrum disorder (NMOSD). Although IL-6 inhibitors are generally well-tolerated, serious infections, including sepsis, can occur. In this study, we compared the sepsis characteristics in NMOSD patients administered satralizumab (NMOSD-satralizumab) to those in rheumatoid arthritis patients administered tocilizumab (RA-tocilizumab), another IL-6 inhibitor. Methods We examined adverse event reports from the Japanese Pharmaceuticals and Medical Devices Agency regarding NMOSD-satralizumab from August 2020 to March 2022 and RA-tocilizumab from April 2008 to November 2019 (term 1) and to March 2022 (term 2). Results We identified 6 sepsis cases in NMOSD-satralizumab, of which 5 (83%) developed from urinary tract infections (UTIs). Although data were unavailable for two patients, three cases had urologic complications in addition to recognized risk factors for serious infections, such as an older age, corticosteroid use, obesity, diabetes mellitus and motor disability. Urosepsis was relatively infrequent in RA-tocilizumab (term 1: 24.2%, term 2: 20.1%). Conclusion Safe satralizumab use requires risk factor assessment to minimize the incidence of severe infections. Management of UTIs is also recommended.

A Clinical Approach to Existing and Emerging Therapeutics in Neuromyelitis Optica Spectrum Disorder

PURPOSE OF REVIEW

Neuromyelitis optica spectrum disorder (NMOSD) is a rare but highly disabling disease of the central nervous system. Unlike multiple sclerosis, disability in NMOSD occurs secondary to relapses that, not uncommonly, lead to blindness, paralysis, and death. Recently, newer, targeted immunotherapies have been trialed and are now in the treatment arsenal. We have endeavoured to evaluate the current state of NMOSD therapeutics.

RECENT FINDINGS

This review provides a pragmatic evaluation of recent clinical trials and post-marketing data for rituximab, inebilizumab, satralizumab, eculizumab, and ravalizumab, contrasted to older agents. We also review contemporary issues such as treatment in the context of SARS-CoV2 infection and pregnancy. There has been a dramatic shift in NMOSD morbidity and mortality with earlier and improved disease recognition, diagnostic accuracy, and the advent of more effective, targeted therapies. Choosing a maintenance therapy remains nuanced depending on patient factors and accessibility. With over 100 putative agents in trials, disease-free survival is now a realistic goal for NMOSD patients.

Satralizumab: A Review in Neuromyelitis Optica Spectrum Disorder

Satralizumab (Enspryng^®) is a monoclonal antibody that blocks the interleukin-6 (IL-6) receptor and is approved for the treatment of neuromyelitis optica spectrum disorder (NMOSD) in patients who are aquaporin-4 immunoglobulin G (AQP4-IgG) seropositive. Patients with NMOSD are at risk of recurrent autoimmune attacks that primarily target the optic nerves and spinal cord but may also target other regions of the central nervous system; these attacks can lead to life-long disability. In the randomized, placebo-controlled phase III SAkuraSky and SAkuraStar trials, subcutaneous satralizumab as an add-on to immunosuppressive therapy or as a monotherapy, respectively, significantly reduced the risk of relapse compared with placebo in patients who were AQP4-IgG seropositive with NMOSD. Satralizumab was well tolerated; the most common adverse events were infection, headache, arthralgia, decreased white blood cell count, hyperlipidaemia and injection-related reactions. In the EU, satralizumab is the first IL-6 receptor blocker to be approved for treatment of AQP4-IgG-seropositive patients with NMOSD, has the potential advantage of subcutaneous administration, and is the only targeted treatment approved for adolescent patients with this disorder. Thus, satralizumab is a valuable treatment option for patients with NMOSD.

Severe febrile neutropenia associated with satralizumab in an Argentinian neuromyelitis optica spectrum disorder patient

BACKGROUND

Recently, satralizumab (interleukin-6 receptor blocker) was approved for seropositive neuromyelitis optica spectrum disorder (NMOSD) patients. In SAkuraSky trial, mild neutropenia was reported in 15% of patients under satralizumab. Most neutropenias were transient; grade 3-4 was not related to serious infections. So far, no severe neutropenia (<100 cell/mm³) has been reported worldwide.

METHODS

We present an aquaporin-4-antibody-positive NMOSD patient who developed severe febrile neutropenia 2 weeks after adding satralizumab to her azathioprine treatment.

CONCLUSION

Analytic control for satralizumab is recommended at 4 weeks. However, we recommend this control at week 2, in order to closely monitor neutrophil count and prevent further complications.

Long-term Efficacy of Satralizumab in AQP4-IgG-Seropositive Neuromyelitis Optica Spectrum Disorder From SAkuraSky and SAkuraStar

BACKGROUND AND OBJECTIVES

Satralizumab, an interleukin 6 receptor inhibitor, reduced the risk of protocol-defined relapse (PDR) vs placebo in 2 independent, double-blind studies in patients with neuromyelitis optica spectrum disorder (NMOSD). We assessed the long-term efficacy of satralizumab in patients with aquaporin-4-immunoglobulin G (IgG)-seropositive (AQP4-IgG+) NMOSD.

METHODS

Following the double-blind periods of SAkuraSky (satralizumab + baseline immunosuppressive treatment [IST]) and SAkuraStar (satralizumab monotherapy), patients could enter the open-label extension (OLE, satralizumab 120 mg Q4W ± IST). This analysis included all AQP4-IgG+ patients who received ≥1 dose of satralizumab in the double-blind and/or OLE periods, from patients' first dose to the data cutoff (February 22, 2021). PDR in the OLE period was determined by the investigator without external adjudication. We evaluated time to first investigator-reported PDR (iPDR), severe iPDR (≥2 point increase in the Expanded Disability Status Scale [EDSS] score), and sustained EDSS worsening (EDSS score increase of ≥2, ≥1, or ≥0.5 points for patients with baseline scores of 0, 1-5, or ≥5.5, respectively, confirmed ≥24 weeks post-initial worsening), plus the annualized iPDR rate (ARR).

RESULTS

Forty-six of 55 AQP4-IgG+ patients (84%) in SAkuraSky and 57/64 patients in SAkuraStar (89%) continued from the double-blind periods into the OLEs. In total, 111 AQP4-IgG+ patients received ≥1 dose of satralizumab in the double-blind and/or OLE periods and were included in these analyses (SAkuraSky: 49; SAkuraStar: 62). The median (range) duration of satralizumab exposure was 4.4 (0.1-7.0) years in SAkuraSky and 4.0 (0.1-6.0) years in SAkuraStar, with a combined 440.1 patient-years of treatment. Seventy-one of 111 patients (64%) received satralizumab for ≥192 weeks (3.7 years). At this time point, 71% (SAkuraSky) and 73% (SAkuraStar) of satralizumab-treated patients were free from iPDR, 91% (SAkuraSky) and 90% (SAkuraStar) were free from severe iPDR, and 90% (SAkuraSky) and 86% (SAkuraStar) had no sustained EDSS worsening. The overall adjusted ARR (95% CI) was 0.12 (0.08-0.18) in SAkuraSky and 0.08 (0.05-0.13) in SAkuraStar and remained stable over time.

DISCUSSION

These long-term results from the OLE periods of the SAkura studies demonstrate the continued efficacy of satralizumab over more than 3.5 years of treatment. High proportions of patients remained free from relapse, severe relapse, or worsening disease, with a consistently low ARR.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov registration numbers: NCT02028884 (SAkuraSky) and NCT02073279 (SAkuraStar).

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that satralizumab reduces the risk of relapse in patients with AQP4-IgG+ NMOSD beyond the first 96 weeks of treatment.