New patent filing covering a novel class of drugs and their use in the treatment of a wide range of skin diseases and certain cancers

20th March 2006: York Pharma plc, the AIM-listed strategic acquirer, developer and marketer of pharmaceutical products in the field of dermatology, announces the filing of a new patent, further extending the Company’s ownership of a novel class of drugs having anti-proliferative activity. The new class of drugs may prove useful in the treatment of a wide range of chronic diseases including psoriasis, acne vulgaris, actinic keratosis, solar keratosis, squamous cell carcinoma, ichthyoses, hyperkeratosis and disorders of keratinisation such as Darrier’s disease and certain cancers.

Following the discovery and identification of a chemical structure that confers anti-proliferative activity to novel molecules, York Pharma’s research team has described a new class of drugs for the treatment of hyperproliferative diseases.

Included in the new class of drugs known as the Vitamin A Metabolic Pathway (VAMP) Inhibitors is VampexTM (carbenoxolone), York Pharma’s lead candidate for the treatment of psoriasis and referred to previously as YP003 in the Company’s portfolio. The Company reported positive phase II clinical results with Vampex™ in psoriasis earlier in the year.

Pivotal research findings demonstrated that blocking the vitamin A metabolic pathway in mammalian cells had the same beneficial inhibitory effect on cell proliferation as exposure to high levels of vitamin A derivatives, an approach taken by existing vitamin A therapies but associated with frequent adverse effects limiting their use. York Pharma has identified a specific method of blocking this pathway using a compound that inhibits one of the key enzymes involved in the conversion of vitamin A to its active derivatives. This discovery enables York Pharma’s VAMP Inhibitors to embrace the benefits of existing vitamin A therapies whilst avoiding their wide range of adverse effects.

Further investigation into the chemistry of Vampex™, in combination with in silico (computer) modelling, has led to the discovery of a critical region of the molecule (a pharmacophore) that is responsible for its anti-proliferative activity.

Subsequent screening of several derivatives of the molecule has now resulted in the selection of several novel compounds that comprise a new group of anti-proliferative drugs that belong to the VAMP Inhibitor class of drugs. Promising results demonstrate that these compounds limit the proliferation of human keratinocytes (skin cells) in vitro. A new patent has now been filed to provide York Pharma with commercial ownership over these molecules thereby further extending the Company’s exclusive position in this promising new class of medicines.

Terry Sadler York Pharma’s CEO commented: ‘This extension of our IP position establishes York as the leader in treating a wide range of hyperproliferative diseases as well as some cancers using VAMP Inhibitors. This opens the way for the development of new and effective treatments for these distressing and intractable diseases’

-ENDS-

For further information please contact:

York Pharma plc +44 (0)870 066 4453

Terry Sadler, CEO

Northbank Communications +44 (0)207 886 8150

Annabel Entress/Sue Charles

Notes to editors:

About VAMP inhibitors

Vitamin A and its derivatives are crucial regulators of critical cell processes such as proliferation and differentiation and, as such, are vital for the maintenance of normal function in many body tissues, including the skin. Hyperproliferative diseases such as psoriasis are characterised by an imbalance in proliferation and differentiation. Current treatments for hyperproliferative disease based on the vitamin A pathway involve exposure to high levels of vitamin A derivatives, to which many patients experience side-effects or resistance to therapy. In contrast, VAMP inhibitors reduce the levels of vitamin A derivatives in the cell but retain the same anti-proliferative effects.

About VampexTM

As reported on the 30th January 2006, the Company has identified a class of Vitamin A Metabolic Pathway (VAMP) inhibitors from which the well-established cytoprotectant drug, VampexTM, previously known as carbenoxolone, was selected as the lead candidate for clinical development as a novel treatment for psoriasis. The discovery of novel VAMP inhibitors further extends York Pharma’s exclusive position in this area.

About Psoriasis

Psoriasis affects about 2% of the world’s population (ranging from 0.5% in Japan up to 2.5 % in Scandinavia). The condition can arise at any age but appears most often between the ages of 15 to 40. The market is valued presently at approximately $630m but expected to grow to $2bn by 2008. Therapy of mild to moderate psoriasis is dominated at present by topically applied Vitamin D analogues, all of which are prescription therapies. The objective of therapy is to clear all the psoriatic plaques but achievement of that objective by Vitamin D analogues is limited by their propensity to cause skin irritation, a safety profile that limits the amount that can be applied and a tendency to lose efficacy with continuous use.

A study conducted by the National Psoriasis Foundation in the USA found that twenty three percent of Americans having the disease were very dissatisfied with their overall treatment. Seventy eight percent of respondents with moderate to severe psoriasis stated that they did not use the more aggressive therapies to treat their disease due to associated side effects or lack of efficacy. Therefore, psoriasis represents a large dermatology market for which there is an attractive opportunity for products that provide more effective and better tolerated therapeutic options than those available presently.

About York Pharma plc

York Pharma is an AIM-listed strategic acquirer, developer and marketer of pharmaceutical products in the field of dermatology. Its portfolio now embraces skin diseases that make up approximately 75% of the global $10.4 bn dermatology market, and its lead product, Abasol for the treatment of fungal infections of the skin was filed for its first marketing approval in July 2005. For further information, please go to www.yorkpharma.com