BENZEFOAM Emollient Foam Demonstrates Significant Reduction inPropionibacterium acnes in Study Presented at the Fall Clinical Dermatology Conference

First study to focus on reduction of P. acnes on the back
CUMBERLAND, R.I.--(Business Wire)--
Onset Therapeutics, a specialty pharmaceutical company focused on dermatology,
today announced that positive data on the reduction of the acne-causing bacteria
Propionibacterium acnes with BenzEFoam (benzoyl peroxide) 5.3% Emollient Foam
was presented at a poster session during the Fall Clinical Dermatology
Conference in Las Vegas, October 15 - 18th. The results were from an
investigator-initiated study by James J. Leyden, MD, Emeritus Professor of
Dermatology at the University of Pennsylvania School of Medicine, assessing
BenzEFoam Emollient Foam, the first prescription foam formulation of benzoyl
peroxide, and a commercially available benzoyl peroxide 8% wash in patients with
P. acnes colonization on their backs.

As an acne treatment, benzoyl peroxide works primarily through its potent
antibacterial effect. In previous studies of patients with P. acnes colonization
on their faces, benzoyl peroxide has demonstrated a 1.0 to 2.0 logarithmic
reduction (equivalent to a 90% to 99% reduction) of P. acnes. Prior to this
study, no data was available that specifically examined P. acnes reduction on
the back with benzoyl peroxide. This five-week, open-label, crossover study
included 20 subjects (>18 years old) with P. acnes colonization on their backs
(>10,000 colonies per cm2).

The study results demonstrated that total P. acnes colony counts were reduced by
>99% after 2 weeks of treatment with BenzEFoam; P. acnes were reduced 1.9 log
after one week of treatment and by 2.1 log after two weeks of treatment with
BenzEFoam. In contrast, the benzoyl peroxide 8% wash did not reduce P. acnes
counts at all after two full weeks of treatment.

"The foam formulation of benzoyl peroxide clearly was effective in reducing P.
acnes counts on the back to the level associated with a therapeutic effect when
it was applied in our study center," said Dr. Leyden.

"BenzEFoam Emollient Foam is effective in reducing P. acnes on the back and is
easy to spread over broad surface areas when acne presents on the chest, back,
and shoulders," said Doug Abel, General Manager of Onset Therapeutics. "Wash-off
formulations of benzoyl peroxide are commonly utilized for the treatment of acne
on the trunk, due to patient convenience of application in the shower. However,
the results of this study may cause a clinician to reconsider that approach and,
in turn, increase their use of a leave-on treatment, such as BenzEFoam, which is
specifically formulated for the treatment of body acne."

Both treatments were well tolerated by the study subjects. Neither treatment
caused skin dryness, redness, scaling, or burning and neither treatment resulted
in any patients discontinuing from the study.

BenzEFoam is indicated for the topical treatment of mild to moderate acne
vulgaris and was designed for patients experiencing acne symptoms on their
backs, shoulders, and chests. This study was supported by a grant from Onset
Therapeutics.

About Acne

Acne vulgaris is a common skin disease, affecting 40 to 50 million Americans.
Approximately 50% of all acne patients have both facial and non-facial acne
symptoms. In the U.S. in the past year, more than five million patients with
acne sought treatment from a physician, resulting in over 17 million
prescriptions filled, according to data from Verispan and IMS.

Indication and Important Safety Information for BenzEFoam Emollient Foam

BenzEFoam (benzoyl peroxide) 5.3% Emollient Foam is indicated for use in the
topical treatment of mild to moderate acne vulgaris. BenzEFoam Emollient Foam
should not be used in patients who have shown hypersensitivity to benzoyl
peroxide or to any of the other ingredients in the product. Allergic contact
dermatitis and dryness have been reported with topical benzoyl peroxide therapy.
When using this product, avoid unnecessary sun exposure and use a sunscreen.
BenzEFoam, like all benzoyl peroxide containing products, may bleach hair or
colored fabrics.

About Onset Therapeutics

Onset Therapeutics is a specialty pharmaceutical company focused on the
development and commercialization of dermatology products formulated with the
Company`s innovative proprietary topical formulation technologies and unique
delivery systems. The Company utilizes its novel DELEVO Foam Technology that is
designed to deliver enhanced penetration of proven active ingredients in
cosmetically elegant, hydrating formulations with the goal of enhancing patient
compliance.

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

For Onset Therapeutics
Mary Theriault, 401-762-2000 ext. 21
mtheriault@onsettx.com

Copyright Business Wire 2009