Therapy Areas: Central Nervous System
Viela Bio Receives US FDA Breakthrough Therapy Designation for Inebilizumab for Treatment of Neuromyelitis Optica Spectrum Disorder
23 April 2019 - - The US Food and Drug Administration has granted Breakthrough Therapy Designation for US-based Viela Bio's anti-CD19 monoclonal antibody inebilizumab, an investigational monotherapy for neuromyelitis optica spectrum disorder (NMOSD), the company said.

NMOSD is a rare, life-threatening autoimmune disease affecting the central nervous system.

Breakthrough Therapy Designation is designed to expedite the development and regulatory review of medicines intended to treat a serious condition that have shown encouraging early clinical results which may demonstrate substantial improvement on a clinically significant endpoint over available medicines.

The designation for inebilizumab is based on data from the pivotal N-MOmentum study evaluating inebilizumab as monotherapy.

The FDA and the European Medicines Agency granted Orphan Drug Designation for inebilizumab for the treatment of patients with NMOSD in March 2016 and March 2017, respectively.

NMOSD is a rare, life-threatening autoimmune disease of the central nervous system in which the body's immune system attacks healthy cells, most commonly in the optic nerves and spinal cord, resulting in severe damage.

NMOSD may cause severe muscle weakness and paralysis, loss of vision, respiratory failure, problems with bowel and bladder function and neuropathic pain.1 There is currently no cure or approved treatment for NMOSD.

Breakthrough Therapy Designation is a US FDA programme designed to expedite the development and review of drugs intended for serious or life-threatening conditions.

In order to receive a BTD, preliminary clinical evidence must demonstrate that the drug may provide substantial improvement over currently available therapy on at least one clinically significant endpoint.

The benefits of BTD include more intensive guidance from FDA on an efficient drug development programme, access to a scientific liaison to help accelerate review time and organizational commitment from FDA.

Neuromyelitis Optica Spectrum Disorders (NMOSD) is a recently proposed unifying term for neuromyelitis optica, also known as Devic's disease, and related syndromes. NMOSD is a rare, severe, relapsing, neuroinflammatory autoimmune disease that can be fatal.

In NMOSD, about 80% of patients have autoantibodies to a water channel protein called aquaporin-4.

These AQP4-IgG autoantibodies are thought to be produced by plasmablasts and plasma cells and bind primarily to astrocytes in the central nervous system.

Binding of AQP4-IgG antibodies to central nervous system cells is believed to trigger attacks, which can damage the optic nerves, spinal cord and brain.

Loss of vision, paralysis, loss of sensation, bladder and bowel dysfunction, nerve pain, and respiratory failure can all be manifestations of the disease.

Each NMOSD attack leads to further damage and disability. 

NMOSD occurs more commonly in women and it may be more common in non-Caucasians. There is currently no cure or approved treatment for NMOSD.

Inebilizumab is a humanised monoclonal antibody that binds with high affinity to CD19, a protein expressed on a broad range of B cells, including antibody-secreting plasmablasts and some plasma cells.

After binding to CD19, these cells are rapidly depleted from the circulation.

The N-MOmentum study enrolled 231 NMOSD patients, including patients with and without AQP4-IgG antibodies. Patients were randomised to receive two intravenous doses of inebilizumab monotherapy or placebo and followed for 6.5 months.

Patients were subsequently placed into open label extension in which all patients received inebilizumab every six months.

The primary endpoint was time from treatment initiation to occurrence of an NMOSD attack. NMOSD attack diagnosis was standardised using 18 clinically meaningful criteria that were developed for the study.

These criteria were defined and established prospectively.

An independent, blinded external adjudication committee reviewed all NMOSD attacks. An open-label study is ongoing, with patients receiving an inebilizumab infusion every six months.

Viela Bio, headquartered in Gaithersburg, Maryland, is a clinical-stage biotechnology company pioneering and advancing treatments for severe inflammation and autoimmune diseases by selectively targeting shared critical pathways that are the root cause of disease.