Viela Bio Receives U.S. FDA Breakthrough Therapy Designation for Inebilizumab for Treatment of Neuromyelitis Optica Spectrum Disorder

Designation based on positive primary analysis of pivotal study,
N-MOmentum

GAITHERSBURG, Md.–(BUSINESS WIRE)–Viela Bio today announced that the U.S. Food and Drug Administration
(FDA) has granted Breakthrough Therapy Designation (BTD) for the
Company’s anti-CD19 monoclonal antibody inebilizumab, an investigational
monotherapy for neuromyelitis optica spectrum disorder (NMOSD). NMOSD is
a rare, life-threatening autoimmune disease affecting the central
nervous system.

“The Breakthrough Therapy Designation for inebilizumab is based on
results from the largest monotherapy study ever conducted in NMOSD,”
said Jorn Drappa, M.D., Ph.D., Chief Medical Officer and Head of
Research & Development at Viela Bio. “Inebilizumab is a humanized
monoclonal antibody designed to bind with high affinity to CD19 and
deplete a broad range of B cells, including autoantibody-secreting
plasmablasts and CD19-expressing plasma cells. We continue our efforts
to bring inebilizumab to patients suffering from this devastating
disease for which there are currently no approved medicines.”

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.

About Breakthrough Therapy

Breakthrough Therapy Designation (BTD) is a U.S. FDA program 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 program, access to a
scientific liaison to help accelerate review time and organizational
commitment from FDA.

About Neuromyelitis Optica Spectrum Disorders (NMOSD)

NMOSD is a recently proposed unifying term for neuromyelitis optica
(NMO)—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 (AQP4). 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.

About Inebilizumab

Inebilizumab is a humanized 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.

About N-MOmentum

The N-MOmentum study enrolled 231 NMOSD patients, including patients
with and without AQP4-IgG antibodies. Patients were randomized 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 6
months. The primary endpoint was time from treatment initiation to
occurrence of an NMOSD attack. NMOSD attack diagnosis was standardized
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 6 months. More information can be found on clinicaltrials.gov.

About Viela Bio

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.

For more information, please visit www.vielabio.com.

Contacts

Investors:
Solebury Trout
Chad Rubin
646-378-2947
[email protected]

Media:
Solebury Trout
Amy Bonanno
914-450-0349
abonanno@soleburytrout.com