PPL Therapeutics plc ("PPL") Announces Status of Phase III AAT Trial

December 5, 2001

Edinburgh, Scotland — In an announcement on 15 October PPL indicated that it expected its partner, Bayer, to meet with the U.S. regulator (the Food and Drug Administration or "FDA") in November to discuss the design of its Phase III trial in patients with congenital alpha-1 antitrypsin ("AAT") deficiency.

Today the companies announce updated information about the start of the Phase III clinical trial to evaluate transgenically produced recombinant alpha-1 antitrypsin ("recAAT") for the treatment of hereditary emphysema.

As stated previously, the FDA requested a Phase II study to confirm the safety and tolerability of an increased recAAT concentration together with Bayer’s improved inhalation device.

After a review of the preliminary data from this Phase II study, the FDA suggested that further analyses be conducted focussing on the small number of Phase II patients who did not complete the study.

These analyses are currently being conducted, but are taking longer than expected due to the companies’ desire to submit as full a data set in support of the safety of recAAT as possible. The research team aims to finalise all analyses arising from the Phase II study by the end of December, and be in a position to submit a complete report early in the New Year. The Phase III triail would then commence immediately following a successful meeting with the FDA.

Based on PPL’s initial analysis, and contingent on the outcome of the final discussions with the FDA, we do not expect this recent development to have a significant impact on the timeframe for launching recAAT.

recAAT offers the potential to greatly increase AAT supply because it is not dependent on the availability of human plasma. and convenience to patients. In addition, Tthe aerosol formulation of recAAT will be allow deliveryed directly to the lungs, the organ that is affected by AAT deficiency via a nebulizer, greatly increasing patient convenience and compliance. The formulation is expected to provide improved patient convenience and compliance. In addition, the transgenic source will increase supply of the product, making replacement therapy available for more AAT-deficient patients.

For more information contact:
PPL Therapeutics plc:
April D'Arcy
Tel +44 (0)131 440 4777

Financial PR Enquiries:
Alistair Mackinnon-Musson
Philip Dennis
Hudson Sandler
Tel +44 (0)20 7796 4133

Notes to Editors:

1. PPL Therapeutics is a biopharmaceutical company, which is one of the world’s leaders in the application of transgenic animal technologies to the development and production of human proteins for therapeutic and nutritional applications.
2. PPL’s patented transgenic production of human proteins involves the introduction of copies of human DNA into the genetic material of another species. The resulting transgenic animals express the human gene product (protein) in the mammary gland allowing its collection and purification during lactation. The technique, which offers the opportunity to produce human proteins economically and in potentially unlimited quantities, is based on patented technology developed by the Roslin Institute in the 1980s for which PPL holds an exclusive licence.
3. PPL’s three lead products are AAT, a fibrin sealant, and bile salt stimulated lipase (BSSL).
4. PPL is the only company to offer a wide range of animals for transgenic protein production, including sheep, cows, rabbits, and pigs.
5. Further information on PPL, its products, and technologies can be found at: www.ppl-therapeutics.com .