Algeta ASA has announced that with the results of the BC1-04 study reported today it has completed its comprehensive phase II clinical program evaluating Alpharadin (radium-223) as a new treatment for bone metastases in patients with hormone-refractory prostate cancer (HRPC).
The program provides strong evidence that Alpharadin can prolong patient survival times, improve quality of life and offer a placebo-like safety profile.
These exciting clinical results combined with Alpharadin's unique bone-targeting properties highlight the potential of this new cancer therapeutic to be a first-choice treatment for bone metastases that frequently arise from a number of high incidence cancers as well as HRPC (e.g. breast, lung and thyroid). Bone metastases are a serious consequence of certain advanced cancers causing intractable and debilitating pain as well as further reducing life expectancy.
In addition, the results, including data from the final trial in the program (BC1-04; outlined below), suggest that Alpharadin has an ideal profile to be used in combination with other cancer therapies.
The Alpharadin phase II program comprised three trials and involved 286 individuals. It was designed to provide detailed information on the safety and therapeutic efficacy of different doses of Alpharadin in HRPC patients, both symptomatic and asymptomatic for bone metastases, as well as evaluating its ability to relieve pain caused by bone metastases in symptomatic patients. In all three phase II trials completed, the primary efficacy endpoints were met while providing compelling evidence of the benign, placebo-like safety profile of Alpharadin. In addition, data from the BC1-04 study support an optimal therapeutic dose level of 50 kBq/kg as selected for use in the global phase III ALSYMPCA trial (see below for further details).
Furthermore, the successful completion of the phase II program also supports Algeta's strategy for targeting Alpharadin at patients with metastatic HRPC who are unsuitable or who have failed docetaxel chemotherapy and for first-line use in combination with docetaxel. A combination study is in preparation, which if successful will enable Algeta to market Alpharadin, either alone or in combination with docetaxel, to approximately 85% of the global HRPC market.
Algeta's President and CEO, Dr. Thomas Ramdahl, said: "The completion of the phase II program is an important milestone for Algeta that gives us great confidence in the potential of Alpharadin as a new, safe and effective treatment for metastatic prostate cancer. The program has demonstrated not only that Alpharadin can improve patient quality of life by successfully treating the painful and debilitating bone metastases arising from the primary cancer, but also that it has a proven survival benefit for patients. We believe there is not a single cancer therapeutic available today offering these patients such clinical benefits, let alone one which is so readily tolerated. We remain confident that the phase III clinical program will confirm these impressive results and support a strong case for regulatory approval in due course."
Dr Chris Parker, a prostate cancer specialist based at the Institute of Cancer Research and the Royal Marsden Hospital in Sutton, UK, and the study's principal investigator, said: "The clinical results generated so far for Alpharadin in treating metastatic prostate cancer are highly encouraging and offer patients the possibility of an effective treatment that both prolongs life while also maintaining quality of life. In addition, the results announced today further emphasize the remarkably favourable safety profile of Alpharadin compared to other products used in the treatment of HRPC. This major benefit of Alpharadin makes the ALSYMPCA phase III trial a very attractive option for suitable patients as they can continue to receive best standard care in addition to the study drug."
Results of phase II clinical study BC1-04
The BC1-04 study was a double-blind, randomized, dose-finding, repeat-dose study comparing three different dose levels of Alpharadin given three times with six weeks interval to HRPC patients with skeletal metastases. The drug was given by i.v. injection predominantly on an outpatient basis. The primary study objective was to investigate whether there was a dose-response relationship with respect to the proportion of patients showing a PSA response, and to investigate the six weeks' dosing schedule in order to prepare for possible combination trials with docetaxel.
The primary efficacy objective was met and this showed a dose-dependent effect across the three dose levels; 25 kBq/kg, 50 kBq/kg and 80 kBq/kg, respectively. The secondary, but important, endpoint of bone-specific alkaline phosphatase (b-ALP) also showed a significant dose-dependent effect between the lowest and the two higher dose levels, as well as confirming once more the strong bone-targeting nature of Alpharadin. ALP is a severity marker of metastatic bone disease and of prognostic importance. Again, the benign safety profile of Alpharadin was confirmed. Importantly for a drug in this clinical setting no significant bone marrow toxicity was observed in patients receiving Alpharadin, which suggests that in addition to being a product of choice for patients with bone metastases it may also have an ideal profile to be used in combination with other therapies.
Algeta began enrolling patients for the global phase III ALSYMPCA (ALpharadin in SYMptomatic Prostate CAncer) study in June 2008. Approximately 750 patients are expected to be enrolled in Europe, Asia, South America and Canada.
For more information on the ALSYMPCA trial, please go to http://www.algeta.com and click on the ALSYPMCA link in the menu bar.
Bone is the most common organ to be affected by metastatic cancer (Ref. 1). Approximately 1.5 million cancer patients suffer from bone metastases worldwide and there are some 300,000 new cases each year. Importantly, metastases may stay confined to the skeleton with subsequent morbidity and eventual death almost entirely due to skeletal complications and their treatment.
Some 80% of bone metastases are due to prostate and breast carcinomas. For these high incidence cancers, 65-75% patients with advanced disease will have bone metastases (Ref. 2). They may suffer multiple skeletal complications over several years because the clinical course of metastatic bone disease is relatively long. The effects are often debilitating (intractable bone pain, fractures, hypercalcaemia, and spinal cord compression) and profoundly impair a patient's quality of life.
Bone metastases also occur frequently in patients with lung, kidney and thyroid cancers - respectively in 30-40%, 20-25% and 60% of patients with advanced disease.