Cambridge, MA
May 16, 2007

Gloucester Pharmaceuticals, Inc., an oncology focused biopharmaceutical company, announced today that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation for its novel histone deacetylase inhibitor, romidepsin, for the monotherapy of previously treated peripheral T-cell lymphoma (PTCL). The Company had previously announced that it has reached an agreement with the FDA under the FDA's Special Protocol Assessment (SPA) process for the design of its registration-directed trial of romidepsin in patients with PTCL, and that it has received Orphan Drug Status covering this indication in both the United States and Europe.

" The receipt of Fast Track Designation for PTCL is an important component of our overall product development strategy for romidepsin," commented John McBride, Executive Vice President and Chief Operating Officer at Gloucester. "We now are extremely well positioned to move forward with clinical development of romidepsin for PTCL, having previously secured Orphan Drug Designation and finalized a Special Protocol Assessment with the FDA for this indication. As a novel agent in a new class of drugs, histone deacetylase inhibitors, we believe romidepsin has significant potential as a treatment for a variety of hematological cancers as well as solid tumors," he concluded.

At the American Society of Hematology Annual Meeting held in December 2006 an interim analysis of the NCI's phase II study of romidepsin as a treatment for PTCL was presented. The interim results reported on 36 patients with PTCL. An overall response rate of 30% (11/36) was reported, with 3 complete responses (8%) and 8 partial responses (22%). The overall median duration of response has not yet been reached but was reported as being greater than 12 months. The most common adverse events reported were fatigue, nausea, and vomiting.

About Fast Track Designation
The Fast Track program is designed to facilitate and expedite the development and review of new products that demonstrate the potential to address an unmet medical need for serious or life-threatening conditions. A New Drug Application (NDA) for a Fast Track product may be submitted in sections on a rolling basis, rather than simultaneously. Fast Track designation may further lead to a priority review of an NDA within a 6 month timeframe.

About Special Protocol Assessment
A Special Protocol Assessment is a request for feedback from the FDA that allows a company to receive official evaluation and guidance on the design and size of pivotal clinical trial protocols. A company can request this formal assessment on a pivotal trial that is intended to form the primary basis of an efficacy claim in a New Drug Application (NDA).

About PTCL
Peripheral T-cell lymphoma is a term which encompasses a number of different malignancies of T-cell origin that account for about 10-15% of all cases of non-Hodgkin's lymphoma. PTCL can occur at any age from young adulthood to old age and is slightly more common in men than in women. It is a particularly aggressive form of lymphoma with a short median duration of life expectancy (approximately two years) from diagnosis.

About Romidepsin
Romidepsin is a novel agent in a new class of anti-cancer drugs known as histone deacetylase inhibitors. The Company is conducting a pivotal phase II study of romidepsin for patients with cutaneous T-cell lymphoma (CTCL) and has initiated a pivotal phase II study for patients with peripheral T-cell lymphoma (PTCL). Romidepsin has received both Fast Track and Orphan Drug Designation by the Food and Drug Administration (FDA), and Orphan Drug Designation from the European Agency for the Evaluation of Medicinal Products (EMEA) for CTCL. It has also received Orphan Drug Designation for PTCL from both the FDA and EMEA. Romidepsin is in clinical trials for a variety of other hematologic malignancies and solid tumors including hormone refractory prostate cancer, pancreatic cancer and multiple myeloma. These trials and others are being conducted by the Company or the National Cancer Institute (NCI), under a Cooperative Research and Development Agreement (CRADA) with the Company.

About Gloucester Pharmaceuticals, Inc.
Gloucester Pharmaceuticals, Inc. is a privately-held, venture-backed company that develops and commercializes innovative products for the treatment of cancer patients. Gloucester is headquartered in Cambridge, MA. For more information on Gloucester and our clinical development program visit our website at www.gloucesterpharma.com or call 888-474-2825.