Patients with advanced melanoma experienced higher response rates and longer survival without cancer progression when treated with an experimental anticancer vaccine in addition to standard therapy. These were the preliminary findings from a Phase III clinical trial presented at the 2009 annual meeting of the American Society of Clinical Oncology.
Skin cancer is the most common form of cancer in the United States, with more than one million new cases each year. Skin cancer is often divided into two broad categories: melanoma and non-melanoma. Non-melanoma skin cancer refers to several different types of skin cancer, but the most common types are basal cell carcinoma and squamous cell carcinoma.
Melanoma is less common than non-melanoma skin cancer, but tends to be much more aggressive. Of the more than one million new diagnoses of skin cancer each year, roughly 68,000 involve melanoma. More than 8,000 people die of melanoma each year in the United States. What makes melanoma so dangerous is that it is more likely than other types of skin cancer to spread (metastasize) to other parts of the body. Melanoma can occur anywhere on the body. The first signs of melanoma may be a mole that changes in appearance, bleeds, or has more than one color or an irregular shape.
Treatment of advanced melanoma is challenging, and researchers continue to search for new and more-effective approaches. In the current study, researchers evaluated an experimental anticancer vaccine known as gp100:209-217(210M) peptide. The vaccine acts by stimulating T cells (a type of white blood cell) to attack melanoma cells.
The study enrolled 185 patients with Stage IV or locally advanced Stage III melanoma. Study participants were assigned to receive treatment with IL-2 alone (standard therapy) or with IL-2 plus the vaccine.
Follow-up is not yet complete, but the following results were presented at ASCO:
- Tumor shrinkage occurred in 22% of patients treated with IL-2 plus the vaccine compared with 9.7% of patients treated with IL-2 alone.
- Survival without cancer progression was 2.9 months among patients treated with IL-2 plus the vaccine compared with 1.6 months among patients treated with IL-2 alone.
- Overall survival was17.6 months among patients treated with IL-2 plus the vaccine compared with 12.8 months among patients treated with IL-2 alone. The difference between groups in overall survival did not meet the criteria for statistical significance, suggesting that it could have occurred by chance alone.
- The vaccine was well tolerated. Side effects were swelling and redness at the injection site.
This study is one of the first to show promising results for an anticancer vaccine in melanoma. Researchers will continue to follow the patients enrolled in the study to assess longer-term results.
Reference: Schwartzentruber DJ, Lawson D, Richards J et al. A phase III multi-institutional randomized study of immunization with the gp100:209-217(210M) peptide followed by high-dose IL-2 compared with high-dose IL-2 alone in patients with metastatic melanoma. Presented at the 2009 annual meeting of the American Society of Clinical Oncology, May 29-June 2, 2009, Orlando, FL. Abstract CRA9011.
Copyright © CancerConsultants. All Rights Reserved.