Soliris (eculizumab) has been approved in China for the treatment of adult patients with refractory generalised myasthenia gravis (gMG) who are anti-acetylcholine receptor (AChR) antibody-positive. Soliris is the first and only complement inhibitor approved for the treatment of gMG in China.

The approval by the National Medical Products Administration (NMPA) in China was based on comprehensive results from the Phase III REGAIN trial.[1] In the trial, Soliris demonstrated clinical benefit for patients with anti-AChR antibody-positive gMG who had previously failed immunosuppressive treatment and continued to suffer from significant unresolved disease symptoms.[1] These patients are at an increased risk of disease exacerbations and crises that may require hospitalisation and intensive care and may be life-threatening.[2-7]

Additionally, improvements demonstrated during the initial six-month duration of the REGAIN trial were sustained over a treatment period of more than 130 weeks in the long-term open-label extension trial.[1]

gMG is a rare, debilitating, chronic, autoimmune neuromuscular disease that leads to a loss of muscle function and severe weakness.[8 ]

Yan Chuanzhu, MD, Deputy President and Director of the Department of Neurology at Qilu Hospital of Shandong University, Jinan, China, said: "For some gMG patients, standard treatments such as immunosuppressants may not sufficiently control the disease, leaving patients at risk of serious complications. The approval of Soliris is an important milestone for the gMG community in China, offering a targeted treatment option with significant clinical data and extensive real-world evidence shown to improve the ability to perform activities of daily living and support quality of life."

Marc Dunoyer, Chief Executive Officer, Alexion, said: "Symptoms of gMG, including difficulties seeing, walking, talking, swallowing and breathing, can have a debilitating impact on daily life for patients and their families, representing a critical need for therapeutic advances. We are proud to offer Soliris in China, a first-in-class C5 complement inhibitor and globally established treatment for gMG. We remain committed to expanding access to innovative therapies for rare disease patients in China and around the world."

The safety and tolerability profile of Soliris were consistent throughout the primary treatment period and open-label extension.[1 ]The most common adverse events in the primary treatment period were headache and upper respiratory tract infection.[1,9]

Soliris recently became available in China (https://www.astrazeneca.com/media-centre/press-releases/2022/astrazeneca-expands-global-footprint-in-rare-disease-with-availability-of-first-alexion-rare-disease-therapy-for-patients-in-china.html) for the treatment of paroxysmal nocturnal haemoglobinuria (PNH) and atypical haemolytic uraemic syndrome (aHUS) in adults and children. Soliris is also approved for multiple indications in many countries around the world.

AstraZeneca established a rare disease business unit in China in September 2021. In the future, the company aims to continue introducing more innovative medicines in China, targeting the complement system and beyond, for the treatment of rare diseases including PNH, aHUS, gMG, neuromyelitis optica spectrum disorder (NMOSD), hypophosphatasia, immunoglobulin A nephropathy, lupus nephritis and amyloidosis.

Notes

gMG
gMG is a rare autoimmune disorder characterised by loss of muscle function and severe muscle weakness.[8]

Eighty percent of people with gMG are AChR antibody-positive meaning they produce specific antibodies (anti-AChR) that bind to signal receptors at the neuromuscular junction (NMJ), the connection point between nerve cells and the muscles they control.[8,10-13] This binding activates the complement system, which is essential to the body's defence against infection, causing the immune system to attack the NMJ.[8] This leads to inflammation and a breakdown in communication between the brain and the muscles.[8]

gMG can occur at any age, but it most commonly begins for women before the age of 40 and for men after the age of 60.[4, 14,15] Initial symptoms may include slurred speech, double vision, droopy eyelids and lack of balance; these can often lead to more severe symptoms as the disease progresses, such as impaired swallowing, choking, extreme fatigue and respiratory failure.[16,17]

REGAIN Phase III Trial and Open-Label Extension
The global Phase III randomised, double-blind, placebo-controlled, multicentre 26-week trial evaluated the safety and efficacy of Soliris in adults with refractory gMG. The trial enrolled 125 patients across North America, South America, Europe and Asia with a confirmed diagnosis of refractory gMG with positive serologic test for antibodies against AChR. All patients were required to have previously failed treatment with at least two immunosuppressive agents or failed treatment with at least one immunosuppressive agent and required chronic plasma exchange or IVIg, and had a Myasthenia Gravis-Activities of Daily Living Profile (MG-ADL) total score ≥6 at trial entry.[18]

Patients were randomised 1:1 to receive Soliris or placebo for a total of 26 weeks. Patients initially received 900 mg of Soliris or placebo weekly for 4 weeks followed by 1200 mg of Soliris or placebo 1 week later, and then 1200 mg of Soliris or placebo every 2 weeks. The primary efficacy endpoint of change from baseline in MG-ADL total score at week 26, as well as the three secondary endpoints - changes from baseline in Quantitative Myasthenia Gravis (QMG), Myasthenia Gravis Composite score and Myasthenia Gravis Quality of Life 15-item scale - were assessed using a worst-rank analysis.[9]

Patients who completed the randomised control period were eligible to continue into an open-label extension period evaluating the safety and efficacy of Soliris. 94% (117/125) of patients who completed the REGAIN trial enrolled in the open-label extension, of which 56 continued to receive Soliris and 61 were switched from placebo to Soliris within two weeks of completing the REGAIN trial. The extension trial was completed in January 2019.[19]

Soliris
Soliris (eculizumab) is a first-in-class C5 complement inhibitor. The medication works by inhibiting the C5 protein in the terminal complement cascade, a part of the body's immune system. When activated in an uncontrolled manner, the terminal complement cascade over-responds, leading the body to attack its own healthy cells. Soliris is administered intravenously every two weeks, following an introductory dosing period.

Soliris is approved in the US, EU, Japan and China for the treatment of PNH, aHUS and certain adults with gMG. Additionally, Soliris is approved in the US, EU and Japan for the treatment of certain adults with NMOSD.

Soliris is not indicated for the treatment of patients with Shiga-toxin E. coli-related haemolytic uraemic syndrome.

Alexion
Alexion, AstraZeneca Rare Disease, is the group within AstraZeneca focused on rare diseases, created following the 2021 acquisition of Alexion Pharmaceuticals, Inc. As a leader in rare diseases for more than 30 years, Alexion is focused on serving patients and families affected by rare diseases and devastating conditions through the discovery, development and commercialisation of life-changing medicines. Alexion focuses its research efforts on novel molecules and targets in the complement cascade and its development efforts on haematology, nephrology, neurology, metabolic disorders, cardiology and ophthalmology. Headquartered in Boston, Massachusetts, Alexion has offices around the globe and serves patients in more than 50 countries.

AstraZeneca
AstraZeneca (LSE/STO/Nasdaq: AZN) is a global, science-led biopharmaceutical company that focuses on the discovery, development, and commercialisation of prescription medicines in Oncology, Rare Diseases, and BioPharmaceuticals, including Cardiovascular, Renal & Metabolism, and Respiratory & Immunology. Based in Cambridge, UK, AstraZeneca operates in over 100 countries and its innovative medicines are used by millions of patients worldwide. Please visit astrazeneca.com (http://www.astrazeneca.com/) and follow the Company on Twitter @AstraZeneca (https://twitter.com/AstraZeneca).

Contacts
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References

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