Astex Pharmaceuticals Announces That Tolinapant (ASTX660), a Novel Antagonist of Cellular and X-linked Inhibitors of Apoptosis Proteins, Has Been Granted Orphan Drug Designation for the Treatment of T-cell Lymphomas by the US FDA

Pleasanton, CA, August 31st, 2020. Astex Pharmaceuticals, Inc., a wholly owned subsidiary of Otsuka Pharmaceutical Co., Ltd., based in Tokyo, Japan, announces that the US Food & Drug Administration (FDA) has granted orphan drug designation for the company’s novel, orally administered non-peptidomimetic antagonist of the cellular and X-linked inhibitors of apoptosis proteins (cIAP1/2 and XIAP), tolinapant (formerly known as ASTX660), for the treatment of T-cell lymphoma. Orphan drug designation is granted to drugs intended to treat a rare disease or condition.  In the US an orphan disease is defined as one affecting fewer than 200,000 people. The designation provides for seven years of marketing exclusivity in the US following product approval, as well as certain tax incentives and grants.

“T-cell lymphoma remains a challenging disease area with poor prognosis and high unmet medical need,” said Mohammad Azab, MD, Astex Pharmaceuticals’ president and chief medical officer.  “Astex’s development of tolinapant is aimed at bringing a new therapeutic option for patients with this type of cancer. We are delighted that the FDA has granted the orphan drug designation which recognizes the continued need for development of new treatments for patients with rare diseases such as peripheral T-cell lymphoma and cutaneous T-cell lymphoma.”

ASTX660 is an investigational compound and is not currently approved in any country.


About Tolinapant (ASTX660)

Tolinapant is a novel, orally administered, non-peptidomimetic antagonist of the cellular and X-linked inhibitors of apoptosis proteins (cIAP1/2 and XIAP). Inhibitors of apoptosis proteins (IAPs) are frequently overexpressed in tumor cells and contribute to tumor cell survival and chemo-resistance. By inhibiting IAPs, tolinapant promotes cell death. Tolinapant also acts via a newly described immunomodulatory mechanism which works to enhance an anti-tumor immune response in T-cell lymphomas.  Tolinapant was designed using Astex’s fragment-based drug design technology.

Tolinapant is being evaluated in a phase 1/2 clinical study for the treatment  of advanced solid tumors and lymphomas (see NCT02503423)


About T-Cell Lymphomas

T-cell lymphomas are a rare and heterogeneous group of blood cancers arising from abnormal T-lymphocytes. Approximately 6-10% of non-Hodgkin’s lymphomas (NHL) are T-cell lymphomas.  The American Cancer Society estimates there will be 77,240 new cases of NHL diagnosed in the U.S. in 2020. Tumors of mature T-cell origin are usually referred to as peripheral T-cell lymphomas (PTCL).  The World Health Organization’s 2016 classification describes 29 discrete subtypes of peripheral T-cell lymphoma. T-cell lymphomas generally affect people aged 60 or older, and are more common in men than in women.  While some T-cell lymphomas follow an indolent course, many are aggressive and have poor prognosis.


About Astex Pharmaceuticals, Inc.

Astex Pharmaceuticals, Inc. is a leader in innovative drug discovery and development, committed to the fight against cancer.  Astex is developing a proprietary pipeline of novel therapies and has multiple partnered products in development under collaborations with leading pharmaceutical companies.  Astex is a wholly owned subsidiary of Otsuka Pharmaceutical Co., Ltd., based in Tokyo, Japan.

Otsuka Pharmaceutical Co., Ltd. is a global healthcare company with the corporate philosophy: “Otsuka–people creating new products for better health worldwide.” Otsuka researches, develops, manufactures and markets innovative and original products, with a focus on pharmaceutical products for the treatment of diseases and nutraceutical products for the maintenance of everyday health.

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Contact Details

Martin Buckland
Chief Corporate Officer
Astex Pharmaceuticals, Inc.
4420 Rosewood Drive, Suite 200
Pleasanton 94588, CA, USA
Tel: +1-925-560-2857