Kosan Biosciences Incorporated reported results from an early-phase clinical trial indicating their targeted agent alvespimycin may provide clinical benefit to patients with human epidermal growth factor receptor 2 (HER2)-positive breast or ovarian cancers who have received extensive prior therapies.
Human epidermal growth factor receptor 2 is part of a biological pathway that contributes to the growth and spread of cancer cells. Several types of cancers overexpress HER2, including approximately 25–30% of breast cancers.
Herceptin is an agent that is targeted against HER2 and helps to slow or stop the spread of cancer cells that overexpress HER2. Herceptin is often used in combination with chemotherapy for the treatment of breast cancer that overexpresses HER2. The success of Herceptin has motivated researchers to explore more targeted agents. Many of these agents are currently being evaluated in clinical trials for various types of cancers.
Alvespimycin is an investigative agent that can block the effects of several genes and cellular pathways, including HER2, implicated in the growth and spread of cancer cells. Alvespimycin is still in early clinical trials; however, results from trials appear promising.
Researchers recently conducted a clinical trial evaluating alvespimycin among 24 patients with HER2-positive breast cancer and three patients with ovarian cancer. Patients with breast cancer had received extensive prior therapy, including regimens containing Herceptin. Patients in the trial were treated with a combination of alvespimycin and Herceptin.
- Clinical benefit (regression or stabilization of cancer) was achieved in 42% of patients.
- Side effects were generally mild; the most common side effects were diarrhea, fatigue, nausea, headache, and joint pain.
- One out of three patients with ovarian cancer (HER2 status unknown) who had received 13 prior therapies achieved anticancer responses with alvespimycin and Herceptin.
The researchers concluded that the addition of alvespimvcin to Herceptin appears to provide clinical benefit to a significant percentage of patients with HER2-positive breast cancer who have stopped responding to standard therapies and have received extensive prior therapy. Researchers are expanding clinical trials to further evaluate alvespimvin in the treatment of cancer.
Patients with HER2-positive breast cancer or ovarian cancer whose disease has recurred or progressed following prior therapy may wish to speak with their physician regarding their individual risks and benefits of participation in a clinical trial evaluating alvespimycin or other promising therapeutic options. Two sources of ongoing clinical trials include the National Cancer Institute (www.cancer.gov) and www.eCancerTrials.com.
Reference: Kosan Biosciences Incorporated. Kosan’s Second-Generation Hsp90 Inhibitor, Alvespimycin, Shows 42% Clinical Benefit in Phase 1 HER2-Positive Metastatic Breast Cancer Trial. Available at:http://phx.corporate-ir.net/phoenix.zhtml?c=121014&p=irol-newsArticle&ID=1049521&highlight=. Accessed September 2007.