New treatments for a rare disease that affects the optic nerves and spinal cord

Drug names: Uplizna™ (inebilizumab-cdon)  and Enspryng™ (satralizumab-mwge)
Manufacturers: Viela Bio (Uplizna) and Genentech, Inc. (Enspryng)
Condition: Neuromyelitis optica spectrum disorder in adults (NOSD) with AQP4-IgG positive antibodies
Approved: June 2020 (Uplizna) and August 2020 (Enspryng)

Condition overview

Neuromyelitis optica spectrum disorder is a rare, relapsing, autoimmune, inflammatory disorder affecting the central nervous system (CNS). Estimates are 4,000 to 5,000 patients in the United States have NMOSD. NMOSD mainly affects the optic nerves and the spinal cord. Approximately:

• One third of patients sustain permanent motor disability
• One quarter become wheelchair-dependent
• One fifth suffer from permanent visual disability
• One in ten dies from NMOSD¹

Individuals with NMOSD typically have attacks that cause eye pain and vision loss. They may also have attacks resulting in numbness, weakness, or paralysis of the arms and legs, along with loss of bladder and bowel control. Most attacks occur in clusters, days to months to years apart. These clusters can be followed by partial recovery during periods of remission.² Approximately 50 percent of patients with NMOSD have permanent visual impairment and paralysis caused by NMOSD attacks.²

An estimated 80 to 90 percent of NMOSD patients are considered relapsing; 10 percent are considered highly active (having at least two relapses within 12 months).³ The primary goal of treatment is to prevent relapse as the attacks lead to progressive disability.³

Current treatments

Before 2019, there were no FDA-approved medications for the treatment of NMOSD. However, immunosuppressive therapies (e.g., glucocorticoids, azathioprine, mycophenolate mofetil, methotrexate, cyclophosphamide, tocilizumab, and rituximab) are used off-label to prevent NMOSD relapses.⁴

Soliris received FDA approval in June 2019 for the treatment of NMOSD with anti-aquaporin-4 (AQP4-IgG) positive antibodies. Soliris is given as an IV infusion in a health care setting at a wholesale average cost (WAC) of $700,000/year.⁴

Summary of Uplizna and Enspryng

Treatment for NMSOD in adults who are AQP4-IgG antibody positive (75 to 80 percent percent of those diagnosed) includes two new options.

• Enspryng:  Patients can be at home when they subcutaneously self-inject the first three doses of Enspryng™ over two weeks. Follow-on dosing of Enspryng continues once every four weeks. In the 2 pivotal trials, 76 and 91 percent of patients treated with Enspryng were relapse free at 96 weeks.⁵ The treatment cost affects the pharmacy benefit. First year cost is estimated at a WAC of $220,000.*
• Uplizna: A patient must go to a medical facility to get Uplizna infused intravenously.. The initial loading doses are two sessions over two weeks. Then Uplizna is infused once every six months. Each infusion session takes up to 90 minutes to complete. In the pivotal clinical trial, Uplizna reduced the risk of NMSOD relapse by 77 percent when compared to placebo.⁶ Cost affects the medical benefit. First year cost is estimated at a WAC of $393,000.*

Prime monitors the drug pipeline

There are many drugs to treat NMOSD in the pipeline, but none are expected to come up for FDA approval before 2024.⁷

The drug pipeline is full of new, groundbreaking specialty drugs that may help members feel better and live well. Prime focuses on clinical strategies designed to keep clients ahead of drug trends — because it’s easier to manage change when you see it coming.

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References

1. Alexion Press Releases. © 2020 Alexion Pharmaceuticals, Inc. Accessed on September 17, 2020 at: https://news.alexionpharma.com/press-release/product-news/fda-grants-priority-review-and-accepts-sbla-soliris-eculizumab-treatment-
2. FDA news release. June 17, 2019. U.S. Food and Drug Administration. Accessed on September 17, 2020: https://www.fda.gov/news-events/press-announcements/fda-approves-first-treatment-neuromyelitis-optica-spectrum-disorder-rare-autoimmune-disease-central
3. Ajmera MR, Boscoe A, Mauskopf J, Candrilli SD, and Levy M. Evaluation of comorbidities and health care resource use among patients with highly active neuromyelitis optica. J Neurological Sciences 2018; 384: 96-103.
4. Rare disease data base. NMOSD. © 2020. NORD – National Organization for Rare Disorders, Inc. Accessed September 17, 2020 https://rarediseases.org/rare-diseases/neuromyelitis-optica/
5. FDA Drug Trials Snapshots: Enspryng: https://www.fda.gov/drugs/drug-approvals-and-databases/drug-trials-snapshots-enspryng
6. FDA Drug Trials Snapshots: Uplinza. https://www.fda.gov/drugs/drug-approvals-and-databases/drug-trials-snapshots-uplizna
7. Cortellis.com Search term: neuromyelitis optica spectrum disorder. August 2020.

* Estimates were informed by health economics and outcomes research groups at Viela Bio and Roche.

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