Algeta’s Alpharadin™ reduces PSA levels significantly in a placebo-controlled trial in prostate cancer patients

Oslo, Norway, October 23, 2006 – Algeta ASA, a therapeutics company dedicated to the development of novel anticancer agents based on alpha particle emitting radionuclides, today announced further positive results from a Phase II clinical trial of its lead product Alpharadin™ in patients with hormone-refractory prostate cancer (HRPC). The data were presented at the Prostate Cancer Foundation’s 13th Annual Scientific Retreat (Scottsdale, Arizona, USA, October 19-21, 2006).



The present trial was initiated to study therapeutic efficacy of Alpharadin in HRPC patients with painful skeletal metastases using biomarkers and clinical endpoints as outcome measures. Safety and changes in biomarkers are reported based on analyses at 12 months after start of treatment.

The results presented [Ref.1] show that treatment with Alpharadin, a novel bone-seeking radiopharmaceutical based on the alpha emitter Radium-223, demonstrated strong and consistent effects in this double-blind placebo-controlled trial in 64 HRPC patients. Statistically significant effects indicative of a positive therapeutic effect were shown on a range of biomarkers of bone turnover, including significantly reduced bone alkaline phosphatase (bone-ALP) levels from baseline compared with placebo (p>0.001). Reduction in bone-ALP levels was the primary endpoint of the trial.

Importantly, patients receiving Alpharadin also showed a significant decline in prostate-specific antigen (PSA) levels compared to those receiving placebo (saline). Of 31 evaluable patients receiving Alpharadin, 15 (48%) showed a PSA response ³50% decrease from baseline, compared to only 6 of 27 (22%) in the placebo group (p=0.03). Furthermore, the median time to PSA progression was 26 weeks with Alpharadin vs. 8 weeks with placebo (p=0.04).

PSA is a widely recognized disease biomarker for the diagnosis of prostate cancer, and the measurement of reduced PSA blood levels in response to treatment is indicative of a therapeutic effect.

The beneficial effects on PSA levels had duration of up to three months after the end of treatment. The favourable side effect profile of Alpharadin, i.e. limited reversible bone marrow suppression and low toxicity, may allow longer duration of treatment.

Professor Sten Nilsson, Head of the Urologic Oncology Group at the Karolinska Hospital and Institute in Stockholm and Principal Investigator of the trial, commented: “The results from this Phase II trial continue to demonstrate significant positive effects of Alpharadin (radium-223) treatment in patients with HRPC-associated bone metastases. The PSA response seen in treated patients is particularly promising given that it correlated with the beneficial effects on other markers of bone metastases by Alpharadin treatment. Overall, the biomarker and safety data analysed so far continue to support our view that Alpharadin has the potential to become an important new therapy in this indication.”

“We continue to be very pleased with the results coming out of this trial and excited about the therapeutic potential of Alpharadin,” said Dr Thomas Ramdahl, CEO of Algeta. “Patients will continue to be monitored over the next 12 months and we are excited to see if Alpharadin in this study demonstrates a clinical effect that validates the impressive biomarker data we have seen to date.”

These trial results confirm conclusions from earlier analysis of the biomarker data at four months follow-up, which were presented at the 2006 ASCO Prostate Cancer Symposium in San Francisco, CA, in February 2006.

Further details of the BC1-02 Alpharadin™ Phase II clinical trial

64 HRPC patients participating in the trial at 11 centers in Norway, Sweden and the UK all initially received palliative external beam radiotherapy before being randomized to receive four intravenous injections of Alpharadin (50 kBq per kg body weight) or saline, repeated at four-week intervals. Levels of bone-ALP (primary endpoint), S-PINP (serum procollagen I N propeptide), S-CTX-I (serum C-terminal crosslinking telopeptide of type I collagen), S-ICTP (serum type I collagen cross-linked C-telopeptide) and PSA were analysed (Alpharadin versus saline) at regular time points through out the study. The 12-month data are presented here and patients will be followed to 24 months post-first injection to assess clinical efficacy.

33 patients received Alpharadin and 31 patients received saline. Active treatment resulted in a statistically significant decrease in bone-ALP from baseline compared to placebo. The mean (± SD) change from baseline to four weeks after last injection for Alpharadin (33 patients) was -58% ± 37 versus +47% ± 107 in the placebo group (29 patients), p<0.001.

Algeta has two further pain palliation and therapeutic dose-finding Phase II trials ongoing during 2006.

References

1. Nilsson, S. et al. Double-blind, placebo-controlled trial of Radium-223 adjuvant to external beam radiotherapy demonstrates significant decline in bone-alkaline phosphatase and PSA in patients with hormone refractory prostate cancer (HRPC). Presented at the Prostate Cancer Foundation’s 13th Annual Scientific Retreat, Scottsdale, Arizona, USA, October 19-21, 2006. [The poster may be downloaded from here].

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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.

Contact Information

Dr Thomas Ramdahl

CEO

Algeta ASA

Contact via E-mail