October 14, 2011
For immediate release
Toray Industries, Inc.
Mitsubishi Tanabe Pharma Corporation
Toray, Mitsubishi Tanabe Pharma Reach North American License Agreement on
Antipruritic Agent, TRK-820
Toray Industries, Inc. (headquarters: Chuo-ku, Tokyo; President, CEO and COO:
Akihiro Nikkaku; hereinafter referred to as “Toray”) and Mitsubishi Tanabe Pharma
Corporation (headquarters: Chuo-ku, Osaka; President and CEO: Michihiro Tsuchiya;
hereinafter referred to as “Mitsubishi Tanabe Pharma”) today announced that thecompanies signed an agreement regarding exclusive development and marketing ofTRK-820 (Toray development code; generic name: nalfurafine hydrochloride), an
innovative antipruritic agent developed by Toray, in North America.
TRK-820 is a highly selective κ (kappa) opioid receptor agonist. In Japan, it waslaunched in March 2009 as a treatment for hemodialysis-related uremic pruritus underthe brand name REMITCH® CAPSULES 2.5μg (manufactured and marketing approval
held by Toray; distributed by Torii Pharmaceutical Co., Ltd.; in alliance with Japan
Tobacco Inc.). Clinical development is currently underway also for a treatment ofpruritus caused by chronic liver disease and atopic dermatitis.
Toray and Mitsubishi Tanabe Pharma agreed to start clinical development in North
America for a treatment of hemodialysis-related uremic pruritus, an indication for which
the drug already has been approved and marketed in Japan.
Pruritus experienced by hemodialysis patients is non-inflammatory but generalized andsevere, and it is known to be less related to histamine, a generally known substance forcausing itching. Some patients suffer from lack of sleep due to severe itching, which
worsens their quality of life (QOL). In addition, scratching results in skin inflammationand infections, which aggravate systemic symptoms. It is well known that conventional
antipruritic agents including antihistamines cannot fully suppress this itching; anddevelopment of an effective drug has been long awaited also in North America.
By licensing in TRK-820, Mitsubishi Tanabe Pharma enhances its development pipeline
in North America for renal diseases area, and will actively drive forward its clinicaldevelopment to bring it to the market as early as possible.
Toray hopes that TRK-820 will become a successful global product by synergistic effect1

with Mitsubishi Tanabe Pharma’s business strategy in the renal disease area in NorthAmerica.
See an accompanying material for TRK-820 details.

Contacts for inquiries:
Toray Industries, Inc
Corporate Communications Dept.
Phone: +81-3-3245-5179
Mitsubishi Tanabe Pharma Corporation
Corporate Communications Dept
Phone: +81-6-6205-5211

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<Accompanying material>
1. Pruritus
Pruritus is the severe itching caused by certain diseases or background. Primarydiseases which often cause such itching include chronic renal failure, chronic liverdiseases such as cholestatic cirrhosis and atopic dermatitis.
2. TRK-820 features
TRK-820 is a novel selective κ(kappa) opioid receptor agonist, with a different
mechanism from existing antipruritic drugs such as antihistamine. The drug isthought to suppress the pruritus mediated by the opioid-related mechanism and hence
is expected to be effective in treating itching that is resistant to existing treatments
such as antihistamine drugs. It is also thought to significantly contribute toimprovement in the quality of life (QOL) of hemodialysis patients.
3. Opioid receptors
Receptors are the molecules located on the cell membranes. When receptors arebound by the medical compounds, a biological response is triggered. There are a wide
variety of receptors in the human body and each of them has a different specificity toits binding compounds and pharmacological functions expressed by such bindings.
An opiate is one such medical compound that binds to a receptor and expresses a
response, and its receptors are known as opioid receptors. Whereas it was thoughtthat there was only one type of opioid receptor when it was initially discovered, thesubsequent evolution of the research in the area revealed that it is largely classified
into three receptor types indicated as μ(mu), δ(delta) and κ(kappa).
4. Agonists
Pharmacological molecules which target receptors are divided into agonists andantagonists. An agonist activates or stimulates, and thereby induces either an increase ordecrease in the biological activities by the cell.

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