According to the U.S. National Center for Health Statistics [1], heart disease, malignant neoplasms (cancer) and cerebrovascular diseases (stroke) are the three leading causes of death in the United States, representing 58.6 percent of the total deaths reported in the year 2001. While the leading cause of cancer death for both men and women is lung cancer, prostate cancer is the second cause of cancer death in men, behind lung cancer.

The Phase III clinical trials of potential oncology drug candidates, Tarceva™ and Provenge®, are underway to evaluate the safety and potential effectiveness in treating patients with non-small cell lung cancer (NSCLC) and prostate cancers. Successful development and commercialization of these two new drugs could mean significant revenue generation for the biotechnology and pharmaceutical companies involved. The National Institutes of Health estimates that Americans spend $61 billion in direct medical costs for cancer treatment each year.

Non-Small Cell Lung Cancer Drugs - NSCLC is a disease in which malignant cells form in the tissues of the lung, accounting for almost 80 percent of the total lung cancer cases. This year, the American Cancer Society estimated 173,770 new cases and 160,440 deaths from lung cancer in the United States alone [2]. According to the National Institutes of Health, the present standard treatments, including radiation therapy and chemotherapy, do not cure the cancer in most patients with NSCLC. However, patients who have relapsed after standard therapies can be subject to treatment options that are currently in clinical trials.

One of the treatment options is a target drug, taken orally, called Erlotinib. Erlotinib works by attaching itself to the epidermal growth factor receptor (EGFR), a protein found on the surface of cells, and thereby inhibiting the attachment of the EGFR to the epidermal growth factor (EGF). In cell biology, an attachment of the EGFR to the EGF activates the enzyme tyrosine kinase, which causes the cell to grow and multiply. Hence, an EGFR inhibitor will cause cells to stop growing. Human epidermal growth receptor 1 (HER1) is one of the several proteins which are found on the surface of many tumor cells.

Tarceva™ (Erlotinib HCl), co-developed and commercialized by OSI Pharmaceuticals, Inc. (NASDAQ: OSIP), Genentech (NYSE:DNA), and Switzerland's Roche Holdings, is a small molecule HER1/EGFR inhibitor. The drug is designed to inhibit the tyrosine kinase activity of HER1 and stop tumor cell growth.

Last month at the American Society of Clinical Oncology (ASCO) annual meeting, OSIP presented the results based upon 731 patients with advanced NSCLC whose disease had progressed after one or two courses of chemotherapy. It was found that the median survival among patients who took Erlotinib was 6.7 months compared to 4.7 months for those on a placebo. At one year, 31 percent of the patients taking Erlotinib were still alive compared to 22 percent of those taking the placebo.

Prior to the ASCO meeting, the company released a preliminary finding which then sent the OSIP share price to an all-time high of $98.70 on April 26. Without any additional exciting news, the OSIP share price could fall back to a support level of ~ $55. The mean 12-month price target for OSIP shares, based upon Thompson/First Call, is ~ $107.00.

Last month, Tarceva™ was accepted into the U.S. Food and Drug Administration's Pilot 1 Program for Continuous Marketing Applications. The Pilot 1 Program is designed for products that have been designated Fast Track status and have demonstrated significant promise in clinical trials as a therapeutic advance over available therapy for the disease or condition. 

Prostate Cancer Drugs - Prostate cancer is a malignant tumor that begins most often in the outer part of the prostate, affecting men aged 50 and older. In the United States, prostate cancer affects over one million men with an estimated 220,000 cases diagnosed and 28,900 deaths reported in 2003. Standard treatments for prostate cancer patients are surgery, radiation therapy using high-energy x-rays, and hormone therapy to block testosterone in the prostate in order to stop the cancer cells from growing. 

A combination of standard treatments and hormone therapy for early stage prostate cancer using designer drug "Casodex 150mg", has shown to be effective in reducing the risk of tumor progression by almost a half [3]. Casodex 150mg, which is manufactured by London, UK-based AstraZeneca (NYSE ADS :AZN) is however, not approved by the U.S. Food and Drug Administration. 

If the standard treatments fail, patients may have other treatment options that are currently in clinical trials. One of the treatment options is biotherapy or immunotherapy. Immunotherapy is the cancer treatment that uses the patient’s own immune system to fight cancer when standard therapies have failed.

 Provenge®, developed by Seattle, WA-based Dendreon Corporation (NASDAQ:DNDN), and DCVax-Prostate, developed by Bothell, WA-based Northwest Biotherapeutics, Inc. (NASDAQ:NWBT), are two potential immunotherapy vaccine candidates submitted into the Phase III clinical trials. The DCVax-Prostate vaccine clinical trials were suspended in November 2002 due to financial constraints [4].

Provenge® is a vaccine candidate designed to stimulate the immune system to attack cells that express prostatic acid phosphatase (PAP), a protein expressed on approximately 95 percent of prostate cancer cells. Provenge® vaccine works by activating the patient's antigen presenting cells (APCs) with small pieces of the PAP protein delivered to the patient's APCs using Dendreon's proprietary Antigen Delivery Cassette technology. Fully activated APCs, cells of the immune system that engulf dead or foreign cells and other material, alert other cells of the immune system, including T-cells, a type of white blood cell or leukocyte, to seek out and destroy PAP-containing prostate cancer cells.

A Phase III clinical trial of Provenge® (Trial P-11), is now underway to evaluate the safety and potential effectiveness of Provenge® in treating men with early stage, androgen dependent prostate cancer. Men whose prostate cancer is responsive to hormone treatment are considered androgen dependent. Dendreon has research and development alliances with Genentech, Inc., Abgenix, Inc. (NASDAQ:ABGX) and Dyax Corp (NASDAQ:DYAX). DNDN is now trading at a support level of ~ $10.55, with a 12-month price target of ~ $17.00, based upon Thompson/First Call.

REFERENCES

[1] U.S. National Center for Health Statistics, National Vital Statistics Report, vol. 51, no. 5, March 14, 2003.
[2] American Cancer Society: Cancer Facts and Figures 2004. Atlanta, Ga: American Cancer Society, 2004.
[3] AstraZeneca's Press Release, AstraZeneca responds to FDA Action on Supplemental New Drug Application for Casodex 150mg for Early Prostate Cancer, June 21, 2002.
[4] PRNewswire, Northwest Biotherapeutics, Inc. October 9, 2002.