According to a recent on-line publication of the Journal of Clinical Oncology, the treatment combination consisting of two targeted therapeutic agents, Tarceva plus Avastin provides some of the highest levels of anti-cancer activity ever reported in the treatment of advanced kidney cancer.
The kidneys are a pair of bean-shaped organs located on each side of the spine that filter the blood and eliminate waste in the urine through a complex system of filtration tubules. All of the blood in the body passes through the kidneys approximately 20 times an hour.
Renal cell cancer (RCC) is an uncommon form of cancer that is most often characterized by the presence of cancer cells in the lining of the filtration tubules of the kidney. Cancer that has spread outside the kidney to several and/or distant sites in the body is referred to as metastatic RCC.
At this point, the only agent approved for the treatment of metastatic RCC is Proleukin®, a biologic agent that enhances the immune system to help fight cancer. However, recent advances in clinical trials involving targeted therapy-a treatment that has been designed to target a specific component of a cell-are showing promise.
Recently, the FDA has approved targeted therapeutic agents such as Iressa®, Gleevec®, Herceptin®, Avastin and Erbitux® which have demonstrated a therapeutic benefit with relatively mild side effects in patients. Newer targeted agents are progressing through clinical trials, and researchers continue to evaluate these agents in various types of cancers, either alone or in combination with other drugs or treatment modalities.
One such agent is Tarceva (erlotinib), which is currently approved for the treatment of advanced lung cancer that has progressed following prior therapy. Tarceva is targeted against the epidermal growth factor receptor (EGFR) pathway, which is involved in the replication of cells. By blocking the action of the EGFR, Tarceva reduces or prevents cancer cells from reproducing.
Avastin (bevacizumab) is an additional targeted agent, recently approved for the treatment of colorectal cancer. Avastin is targeted against the vascular endothelial growth factor (VEGF), which is involved in the spread of cancer. Researchers have been evaluating the effectiveness of the combination of Tarceva and Avastin in several types of cancer, in the hopes of preventing growth or spread through different mechanisms of action.
Researchers from the Sarah Cannon Center in Tennesserecently conducted a clinical trial to evaluate Tarceva and Avastin in the treatment of advanced RCC. This trial included 59 patients with recurrent RCC. All patients had surgery to remove their kidney (nephrectomy). Following treatment with Tarceva/Avastin, researchers reported the following results:86% of patients achieved a clinical benefit, with 25% of patients achieving a 50% reduction in their cancer size and 61% achieving either disease stabilization.
- Only 13% of patients had a progression of their cancer while on treatment.
- At 18 months, 60% of patients were still alive.
- Side effects caused by treatment were generally mild, with the most common side effects being high blood pressure, diarrhea, rash, nausea and vomiting.
The researchers concluded that the combination of Tarceva and Avastin achieves high rates of disease responses or stabilization, resulting in high levels of survival at 18 months recurrent RCC with manageable side effects. The researchers added that these rates are some of the highest rates ever achieved in patients with this stage of RCC.
Further evaluation of Tarceva and Avastin are warranted, including a comparison against standard therapy. Patients with recurrent RCC may wish to speak with their physician about the risks and benefits of participating in a clinical trial further evaluating Tarceva/Avastin or other promising therapeutic approaches.
Reference: Hainsworth J, Sosman J, Spigel D, et al. Treatment of Metastatic Renal Cell Carcinoma With a Combination of Bevacizumab and Erlotinib. Journal of Clinical Oncology. 2005. Early on-line publication. DOI: 10.1200/JCO.2005.01.8234