Idera Pharmaceuticals Announces Initiation of a Phase 2 Trial of IMO-8400 in Patients with Moderate to Severe Plaque Psoriasis

  Idera Pharmaceuticals Announces Initiation of a Phase 2 Trial of IMO-8400 in
  Patients with Moderate to Severe Plaque Psoriasis

Business Wire

CAMBRIDGE, Mass. -- June 5, 2013

Idera Pharmaceuticals (NASDAQ: IDRA) today announced that it has initiated
dosing in a randomized, double-blind, placebo-controlled Phase 2 trial of
IMO-8400 in patients with moderate to severe plaque psoriasis. IMO-8400, an
antagonist of the Toll-like receptors (TLRs) 7, 8, and 9, is a lead clinical
candidate in Idera’s autoimmune disease program. In a Phase 1 trial involving
single escalating doses and multiple doses, IMO-8400 was well tolerated and
inhibited TLRs 7, 8, and 9-mediated immune responses. Data from the Phase 1
study will be presented at a scientific meeting in June 2013.

"This Phase 2 trial of IMO-8400 will enable us to evaluate over a 12-week
treatment period the continued trajectory of Psoriasis Area Severity Index
(PASI) score improvement that we observed in the previous 4-week study of our
TLR 7 and 9 antagonist, IMO-3100,” said Robert Arbeit, M.D., Vice President of
Clinical Development at Idera. “We anticipate top-line data from the Phase 2
trial of IMO-8400 to be available by the end of 2013.”

“In our proof-of-concept study with IMO-3100 in patients with psoriasis, we
observed PASI score improvement, which correlated with significant improvement
in psoriasis disease-associated gene profile, including downregulation of the
IL-17 pathway. We believe the inclusion of TLR8 activity with IMO-8400 would
further enhance the clinical activity observed with IMO-3100 in patients with
psoriasis,” said Sudhir Agrawal, D.Phil., Chairman and Chief Executive Officer
of Idera. “We expect that data from the present Phase 2 trial will help inform
our decision on further development of IMO-8400 in patients with psoriasis. In
addition, during the fourth quarter of 2013, we expect to be in a position to
initiate Phase 2 clinical trials in additional autoimmune disease indications,
including lupus.”

About the IMO-8400 Phase 2 Trial in Patients with Moderate to Severe Plaque
Psoriasis

The Phase 2 trial is a randomized, double-blind, placebo-controlled trial of
IMO-8400 monotherapy in patients with moderate to severe plaque psoriasis. In
this trial, 32 patients with PASI scores of 12.5 or greater will be randomized
1:1:1:1 to receive weekly subcutaneous doses of IMO-8400 at 0.075, 0.15, or
0.3 mg/kg/week or placebo for 12 weeks. Safety and improvements in PASI score
will be monitored throughout the trial. The trial is being conducted in the
Netherlands.

About TLRs and Idera's Pipeline

Toll-like Receptors (TLRs) play a key role in immunity and inflammation. Using
a chemistry-based approach, Idera has created compounds targeted to endosomal
TLRs 3, 7, 8, and 9. In autoimmune diseases, immune complexes containing host
DNA/RNA activate TLRs 7, 8, and 9, which induces multiple cytokines that
further exacerbate the disease. Inhibition of these TLRs is a novel approach
for the potential treatment of autoimmune diseases. IMO-8400 is an antagonist
of TLRs 7, 8, and 9, and has shown therapeutic activity in preclinical models
of psoriasis, lupus, and arthritis. In a Phase 1 trial involving single
escalating doses and multiple doses, IMO-8400 was well tolerated and inhibited
TLRs 7, 8, and 9-mediated immune responses. A proof-of-concept Phase 2 study
of TLR antagonism in patients with psoriasis using Idera’s antagonist of TLRs
7 and 9, IMO-3100, showed PASI score improvements which correlated with
significant improvement in psoriasis disease associated gene profile,
including downregulation of the IL-17 pathway.

About Idera Pharmaceuticals, Inc.

Idera Pharmaceuticals applies its proprietary Toll-like receptor (TLR) drug
discovery platform to create immunomodulatory drug candidates and is
conducting clinical development in autoimmune and inflammatory diseases.
Additionally, Idera has a collaboration with Merck & Co. for the use of
TLR-targeted candidates as vaccine adjuvants. For more information, visit
http://www.iderapharma.com.

Idera Forward Looking Statements

This press release contains forward-looking statements concerning Idera
Pharmaceuticals, Inc. that involve a number of risks and uncertainties. For
this purpose, any statements contained herein that are not statements of
historical fact may be deemed to be forward-looking statements. Without
limiting the foregoing, the words "believes," "anticipates," "plans,"
"expects," "estimates," "intends," "should," "could," "will," "may," and
similar expressions are intended to identify forward-looking statements. There
are a number of important factors that could cause Idera's actual results to
differ materially from those indicated by such forward-looking statements,
including whether Idera’s cash resources will be sufficient to fund the
Company’s continuing operations and the further development of the Company’s
autoimmune disease program including the additional clinical trials of
IMO-8400 referred to in this release; whether results obtained in preclinical
studies and early clinical trials will be indicative of results obtained in
future clinical trials; whether products based on Idera's technology will
advance into or through the clinical trial process on a timely basis or at all
and receive approval from the United States Food and Drug Administration or
equivalent foreign regulatory agencies; whether, if the Company's products
receive approval, they will be successfully distributed and marketed; whether
the Company will be able to license any of its TLR target candidates on a
timely basis or at all; whether the Company's collaboration with Merck & Co,
Inc., will be successful; whether the patents and patent applications owned or
licensed by the Company will protect the Company's technology and prevent
others from infringing it; and such other important factors as are set forth
under the caption "Risk Factors" in Idera's Quarterly Report on Form 10-Q for
the quarter ended March 31, 2013 which important factors are incorporated
herein by reference. Idera disclaims any intention or obligation to update any
forward-looking statements.

Contact:

Idera Pharmaceuticals, Inc.
Lou Arcudi, 617-679-5517
larcudi@iderapharma.com