Algeta and Affibody Initiate Anticancer Targeted Therapy Collaboration

Oslo, Norway, and Stockholm, Sweden, August 16, 2006 - Algeta ASA, a therapeutics company developing novel anticancer agents based on alpha-particle emitting radionuclides, and Affibody AB, which is building a pipeline of products based on tumor-targeting affinity molecules, today announced a research collaboration agreement to develop novel targeted radiotherapeutics.
The collaboration will combine Algeta’s TH-1 technology for attaching the alpha-particle emitting radionuclide thorium-227 to peptides and proteins, with Affibody® molecules that specifically target tumor cells over-expressing HER2, such as those present in breast and other cancers.

Targeted radiotherapeutics based on these leading-edge technologies will benefit from the proven high specificity and affinity of Affibody® molecules for their targets, which rivals that of antibodies but with significant physical and production advantages, and the high-energy, short-range alpha particle radiation from thorium-227. When thorium-227-labelled radiotherapeutics attach to tumor cells via unique molecular binding sites, a lethal dose of alpha-particle radiation destroys multiple tumor cells within a limited 2-10 cell diameter range of the binding site while leaving non-tumor tissue largely unaffected.

Clinical data confirm that Affibody® molecules can be engineered to have high tumor specificity. High affinity Affibody® molecules have been developed against a number of relevant therapy target proteins. These molecules will be used as carriers for different types of toxins in tumor therapy. Application of Affibody’s proprietary albumin-binding technology yields Affibody® fusion proteins with biodistribution properties that perfectly match the half-life of thorium-227 (t1/2 = 18.7 days).

“The Affibody® molecules ability to capture a specific tumor target in combination with our thorium-227 labeling technology offers great potential for developing a range of important new anticancer products with increased specificity and potency, and reduced side effects as a result of limited radiation to other tissues,” says Dr Thomas Ramdahl, CEO of Algeta.

Dr Ulf Boberg, CEO of Affibody, commented: “We are very pleased to collaborate with Algeta; it is regarded as a leader in the field of alpha-particle emitters and this collaboration fits well with Affibody’s overall HER2-targeting therapy strategy. Algeta’s nuclides are viewed as superior to gamma- and beta-radiating nuclides for tumor therapy and the combination with the Affibody® molecules’ exquisite target-finding capabilities make this collaboration really exciting.”

Notes to Editors

About Algeta ASA

Algeta ASA is a private therapeutics company built on world-leading expertise in nuclear medicine and oncology and dedicated to the development of novel anticancer therapeutics based on alpha particle emitting radionuclides.

By harnessing the unique characteristics of alpha emitters, such as high potency and short range, Algeta is developing new therapeutic candidates and technologies targeting metastatic and disseminated tumors and promising unrivalled potency without unacceptable toxicities.

Algeta’s lead product candidate, Alpharadin, is currently in Phase II clinical trials as a potential new treatment for bone metastases from prostate cancer. Alpharadin is a novel bone-seeking radiopharmaceutical based on the alpha particle emitter radium-223.

Algeta is also developing other technologies for delivering alpha-emitters including microparticles, liposomes and its TH-1 technology, which is designed to enhance the potency of therapeutic antibodies and other tumor-targeting molecules by linking them to the alpha-particle emitter thorium-227.

The Company is headquartered in Oslo, Norway, and was founded in 1997 as Anticancer Therapeutic Inventions.

For more information, visit www.algeta.com.

About Affibody AB

Affibody is a life sciences company focusing on oncology. The company has developed a late-stage pipeline of oncology products for molecular imaging, targeted therapy and biotechnology applications.

The key components of Affibody’s proprietary technology platform are unique and highly specific affinity ligands: Affibody® molecules. These small robust protein molecules are easy to produce and can be designed to bind to any target protein. The Affibody® molecules are ideal for molecular imaging. Importantly, the same Affibody® molecule can, with a cytotoxic payload, be used for targeted therapeutics. Affibody’s vision is to be a leading player in the emerging field of molecular imaging and targeted therapeutics.

The company’s lead product for molecular imaging is targeting HER2, a key receptor on e.g. certain breast cancer tumors. Affibody® molecules specific for other oncology targets are in development and will provide a steady stream of new molecular imaging products and subsequently, targeted therapeutic products. Affibody also develops Affibody® molecules for various biotechnology and research applications.

Affibody was founded in 1998 by researchers from the Royal Institute of Technology and the Karolinska Institute in Stockholm. Investors in Affibody AB include HealthCap, Schroder Ventures Life Sciences and Investor Growth Capital. Affibody is based in Stockholm, Sweden and has 50 employees. Further information is found on: www.affibody.com


Statements in this press release that are not strictly historical may be forward-looking and include risks and uncertainties. Therefore, though based on Affibody’s current expectations, it should be duly noted that a variety of factors could cause actual results and experiences to differ materially from what is herein expressed. Risks and uncertainties include, but are not limited to, risks associated with the management of growth and international operations (including effects of currency fluctuations), variability of operating results, unforeseen changes in the diagnostic and pharmaceutical markets, market competition, rapid or unexpected changes in technologies, fluctuations in product demand, difficulties to successfully develop, adapt, produce or commercialize products, the ability to identify and develop new products and to differentiate products from those of competitors, as well as various legal hazards.

Contact Information

Dr Thomas Ramdahl

CEO

Algeta ASA

Contact via E-mail