Exicure to Present Data at the Cure Spinal Muscular Atrophy Annual Conference in Dallas

Exicure’s three-dimensional spherical nucleic acid containing the
nusinersen sequence prolongs survival and reduces toxicity compared to
nusinersen in a spinal muscular atrophy mouse model

SKOKIE, Ill.–(BUSINESS WIRE)–Exicure, Inc. (OTCQB:XCUR), the pioneer in gene regulatory and
immunotherapeutic drugs utilizing three-dimensional, spherical nucleic
acid (SNA™) constructs, announced today that Exicure and its
collaborators at The Ohio State University Wexner Medical Center will
show preclinical data demonstrating the performance of Exicure’s SNA
compound designed for use in spinal muscular atrophy (SMA). These data
will be presented at the Cure SMA Annual Conference in Dallas, Texas on
June 14, 2018.

Exicure’s spherical nucleic acid version of nusinersen demonstrates
increased survival and decreased toxicity in the
translationally-relevant SMA mouse model,” said David Giljohann, PhD,
CEO of Exicure. “We believe these results are important for developing
improved treatments for patients with SMA. These data also suggest that
Exicure’s technology platform could potentially create more potent
therapies for other disorders of the central nervous system, including
Huntington’s disease, Alzheimer’s disease, and Parkinson’s disease.”

At the meeting, Arthur Burghes, PhD, from Ohio State’s Wexner Medical
Center, and Exicure will present data from preclinical studies in a SMA
mouse model. The poster is titled “Nusinersen in spherical nucleic acid
(SNA) format improves efficacy both in vitro in SMA patient
fibroblasts and in Δ7 SMA mice and reduces toxicity in mice.” The
presentation will highlight that Exicure’s proprietary technology:

  • Prolonged survival by four-fold (maximal survival of 115 days compared
    to 28 days for nusinersen-treated mice);
  • Doubled the levels of healthy full-length SMN2 mRNA and protein in SMA
    patient fibroblasts when compared to nusinersen;
  • Doubled the quantity of healthy full-length SMN mRNA levels in spinal
    cord tissue compared to untreated mice;
  • Mitigated toxicity of nusinersen at the highest dose tested in mice.

In August 2017, Exicure and The Ohio State University established a
collaboration to further validate and characterize the pharmacology of
Exicure’s nusinersen-SNA compound in mouse models. This collaboration’s
ongoing in vivo research is conducted by Dr. Burghes, an
internationally known researcher, leading basic and clinical research on
SMA and other genetic neuromuscular disorders.

About Exicure, Inc.

Exicure, Inc. is a clinical stage biotechnology company developing a new
class of immunomodulatory and gene regulating drugs against validated
targets. Exicure’s proprietary 3-dimensional, spherical nucleic acid
(SNA™) architecture unlocks the potential of therapeutic
oligonucleotides in a wide range of cells and tissues. Exicure’s lead
programs address oncology, inflammatory diseases and genetic disorders.
Exicure is based outside of Chicago, IL. For more information, please
visit www.exicuretx.com.

About Spinal Muscular Atrophy (SMA)

SMA is the most common genetic cause of death for infants. SMA results
from the loss of the SMN1 gene and an inability of SMN2 to produce
sufficient full-length protein to make up for the loss of SMN1. The SMN1
gene, in a healthy person, produces a full-length protein that is
essential to the function of the nerves that control muscles. Without
sufficient SMN protein, the nerve cells cannot properly function and
eventually die. This leads to debilitating and even fatal muscle
weakness.

About Nusinersen

Nusinersen, marketed as Spinraza® by Biogen, is a modified
antisense oligonucleotide. In December of 2016, nusinersen was approved
by the US FDA for the treatment of SMA in pediatric and adult patients.

Forward Looking Statements

This press release contains forward-looking statements (including within
the meaning of Section 21E of the United States Securities Exchange Act
of 1934, as amended, and Section 27A of the United States Securities Act
of 1933, as amended) concerning the Company, the Company’s technology,
potential therapies, pre-clinical results, and other matters.
Forward-looking statements generally include statements that are
predictive in nature and depend upon or refer to future events or
conditions, and include words such as “may,” “will,” “should,” “would,”
“expect,” “plan,” “believe,” “intend,” “look forward,” and other similar
expressions among others. Statements that are not historical facts are
forward-looking statements. Forward-looking statements are based on
current beliefs and assumptions that are subject to risks and
uncertainties and are not guarantees of future performance. Actual
results could differ materially from those contained in any
forward-looking statement as a result of various factors, including,
without limitation: that Exicure’s pre-clinical programs do not advance
into the clinic or result in approved products on a timely or cost
effective basis or at all; regulatory developments; and the ability of
Exicure to obtain sufficient funding for its programs and to protect its
intellectual property rights. Exicure’s pipeline programs are in various
stages of pre-clinical and clinical development, and the process by
which such pre-clinical or clinical therapeutic candidates could
potentially lead to an approved therapeutic is long and subject to
significant risks and uncertainties. Risks facing the Company and its
programs are set forth in the Company’s filings with the SEC. Except as
required by applicable law, the Company undertakes no obligation to
revise or update any forward-looking statement, or to make any other
forward-looking statements, whether as a result of new information,
future events or otherwise.

Contacts

Media
For Exicure, Inc.
Karen Sharma, 781-235-3060
ksharma@macbiocom.com
or
Investor
The
Del Mar Consulting Group, Inc.
Robert B. Prag, 858-794-9500
President
bprag@delmarconsulting.com