Tioga Pharmaceuticals' Asimadoline Demonstrates Positive Results in a Phase 2b Clinical...

Tioga Pharmaceuticals' Asimadoline Demonstrates Positive Results in a Phase 2b
Clinical Trial for the Treatment of Irritable Bowel Syndrome
Statistically Significant Reduction of IBS Pain and Normalizing Motility
Effect Observed

SAN DIEGO, May 20 /PRNewswire/ -- Tioga Pharmaceuticals, Inc. today
announced the results of a recent Phase 2b study of its oral kappa opioid
receptor agonist, asimadoline, which demonstrated statistically significant
results in the treatment of Irritable Bowel Syndrome (IBS). Asimadoline
produced significant improvement in diarrhea-predominant (D-IBS) and
alternating (A-IBS) patients across multiple parameters including the primary
endpoint of pain, as well as secondary endpoints of urgency, frequency and
bloating in both males and females. In D-IBS patients, therapeutic benefit was
observed within the first month of treatment and was sustained for the three
month duration of the trial. Asimadoline appeared to be well tolerated with
no adverse events occurring in a dose-dependent manner throughout the
randomized, double-blind, placebo-controlled, dose-ranging clinical trial
involving 596 subjects. These data were featured today in a late-breaking
oral presentation session at the Digestive Disease Week 2008 Annual Meeting.
Study Results
Of the 596 patients randomized in the trial, approximately 33 percent were
characterized as D-IBS, 37 percent constipation predominant (C-IBS) and 31
percent alternating between diarrhea and constipation (A-IBS).
-- In the overall patient group, patients with at least moderate pain
achieved a 17 percent improvement in percent number of months with
adequate relief of IBS pain compared to placebo (40 percent vs. 23
percent) with both the 0.5 mg (p=0.006) and the 1.0 mg (p=0.005) dose
of asimadoline.
- Evaluation by IBS subtype revealed benefit in D-IBS and A-IBS
patients.
- Benefit in C-IBS patients was not observed.
- The rate of adverse events was similar in asimadoline and placebo
treated subjects.

-- Patients with D-IBS with at least moderate pain achieved a 27 percent
improvement in the percent number of months with adequate relief of
IBS pain compared to placebo (47 percent vs. 20 percent, p=0.011) with
the 0.5mg dose of asimadoline.
- A 25 percent increase in pain free days was seen with 0.5 mg
asimadoline as compared with placebo (p=0.001) during the 12-week
dosing period. This represents an increase of approximately 20
pain free days over that seen with placebo.
- Statistically significant (p<0.05) improvement in pain was seen by
week three and persisted for the duration of treatment.
- Statistically significant improvements were also seen in D-IBS
patients receiving the 0.5 mg dose of asimadoline in all of the
following secondary endpoints: urgency, adequate relief of IBS
symptoms, stool frequency, bloating and daily pain. Statistically
significant improvement was also seen in urgency, adequate relief
of IBS symptoms, bloating and daily pain in patients receiving
the 1.0 mg dose.
- Benefit was seen in female and male patients.

-- Patients with A-IBS with at least moderate pain achieved a 23 percent
improvement in the percent number of months with adequate relief of
IBS pain compared to placebo (50 percent vs. 27 percent, p=0.022) with
a 1.0 mg dose of asimadoline.
- Statistically significant benefit was also seen in the secondary
endpoint of adequate relief of IBS symptoms in patients receiving
the 1.0 mg dose of asimadoline compared to placebo (57 percent vs.
33 percent, p=0.032).
- Benefit was seen in female and male patients.

Study Design
D-IBS, C-IBS, and A-IBS patients were recruited. Patients underwent a
two-week screening, a 12-week treatment and a four-week follow-up period, and
they received identical appearing placebo, 0.15 mg, 0.5 mg or 1.0 mg tablets
of asimadoline twice daily for the treatment period. Throughout the trial,
patients entered data daily by IVRS (interactive voice response system). The
primary endpoint was number of months a patient was a responder for adequate
relief of pain, where the primary measure was the question, "In the past 7
days have you had adequate relief of your IBS pain or discomfort?" asked once
every 7 days. A monthly responder replied "yes" at least three weeks per
month. The secondary endpoints were abdominal pain, stool frequency and
consistency, urgency, bloating, adequate relief of IBS symptoms and straining.
Secondary endpoints were also collected using IVRS. Adverse events, labs and
echocardiograms were also collected.
About Irritable Bowel Syndrome
Irritable bowel syndrome is a common, chronic gastrointestinal disorder
characterized by abdominal pain and discomfort associated with alterations in
bowel habits. The bowel abnormalities may manifest as diarrhea-predominant
disease, constipation-predominant disease, or alternation between diarrhea and
constipation. IBS is estimated to afflict approximately 12 percent of the
adult population in the United States and Europe, with roughly equal
prevalence of each subtype. For reasons that remain unknown, IBS is a
female-predominant disorder, with two-thirds to three-quarters of the subjects
being female.
Lotronex (alosetron), a selective 5-HT3 receptor antagonist, is the only
drug currently approved by the FDA for the treatment of D-IBS; however, due to
safety concerns, Lotronex was removed from the market in 2001 and re-launched
in 2002 under a strict risk management program. No treatment is currently
approved by the FDA for A-IBS. There is, therefore, an urgent unmet clinical
need for a safe and effective treatment for the 20 million Americans who
suffer from D-IBS and A-IBS.
About Asimadoline
Asimadoline is an orally administered small molecule that is a highly
selective kappa opioid receptor agonist. Kappa opioid receptors are found in
the digestive tract and are believed to play an important role in control of
visceral pain and bowel motility. Asimadoline was originally discovered by
Merck KGaA of Darmstadt, Germany. In 2005, Tioga purchased asimadoline from
Merck and acquired by assignment all worldwide rights. Asimadoline has been
tested in over 1100 subjects and has demonstrated a promising safety profile.
About Tioga
Tioga Pharmaceuticals, Inc. is a pharmaceutical company headquartered in
San Diego, CA focused on developing novel treatments for gastrointestinal
diseases. Tioga is currently planning Phase 3 development of asimadoline for
the treatment of D-IBS and A-IBS and a Phase 2b trial of asimadoline for the
treatment of functional dyspepsia. Both disorders represent a large unmet
medical need and a substantial market opportunity. For more information,
please visit http://www.tiogapharma.com.
Contact: David Urso, Chief Business Officer and General Counsel
Phone: 858-964-5021
Email: urso@tiogapharma.com

Media: Cory Tromblee, Porter Novelli Life Sciences
Phone: 617-897-8294
Email: ctromblee@pnlifesciences.com

SOURCE Tioga Pharmaceuticals, Inc.

David Urso, Chief Business Officer and General Counsel of Tioga
Pharmaceuticals, Inc., +1-858-964-5021, urso@tiogapharma.com; or media, Cory
Tromblee of Porter Novelli Life Sciences, +1-617-897-8294,
ctromblee@pnlifesciences.com, for Tioga Pharmaceuticals, Inc.