Results from a phase III trial reveal that men with advanced prostate cancer can significantly benefit from a new medication, abiraterone acetate, called Zytiga.

The researchers found that the drug maintained patients’ quality of life, slowed down the spread of cancer, and delayed the development of pain and deterioration of the patients’ overall condition.

During the trial, individuals assigned to placebo were allowed to switch to zytiga because of the favorable results. According to the researcher zytiga could provide new treatment options to individuals suffering from prostate cancer.

Charles J. Ryan, MD, an associate professor of clinical medicine at the UCSF Helen Diller Family Comprehensive Cancer Center, and lead researcher of the international trial, presented the study on June 2 at the 48th annual meeting of the American Society of Clinical Oncology in Chicago.

Ryan explained:

“This drug extended lives and gave patients more time when they weren’t experiencing significant pain from the disease.

This is an interim analysis, the final analysis should be available in 2014. But it appears that this medication may lay a foundation for the use of this drug at an earlier stage of prostate cancer, and its benefits may be able to be delivered to a much wider population of patients as a result.”

Prostate cancer is the second most prevalent form of cancer in men. Each year around 30,000 people die from the disease. According to the researchers around 33% of prostate cancer patients do not need treatment as their cancer does not metastasize, while another third of patients are treated and cured. However, for some patients the disease will recur after treatment and metastasize to the lymph nodes, bones, or other parts of the body. The disease can become deadly once it metastasizes and rejects standard treatment.

Eric J. Small, M.D., a UCSF professor and chief of hematology and oncology at the UCSF Helen Diller Family Comprehensive Cancer Center, explained: “These results are the culmination of years of research, and will truly transform the way we take care of patients with advanced prostate cancer. This is a wonderful milestone in our progress in treating prostate cancer, and provides advanced prostate cancer patients everywhere with an important new weapon to fight their cancer.”

Abiraterone acetate was approved by the U.S. Food and Drug Administration in 2011, for men with prostate cancer whose disease has metastasized and who were also resistant to standard hormonal therapy, known as castration-resistant prostate cancer (CRPC) and had received chemotherapy with docetaxel.

The Phase III trial involved 1,088 men at 151 cancer facilities in North America, Europe and Australia, whose cancer had metastasized and had become resistant to initial hormone therapy. The study participants did not display significant symptoms from the disease and had also not yet received any chemotherapy. On average, the study participants had been diagnosed with prostate cancer five years earlier.

Patients were assigned to receive either Zytiga in combination with low-dose prednisone or placebo. However, those assigned to placebo were offered Zytiga after the drug showed to delay the need for chemotherapy and pain medications, improve survival and quality of life.

In addition, the researchers found that the drug slowed the spread of cancer by an average of 16 months.

Ryan explained:

“This trial with a well-tolerated oral agent slowed the progression of the disease while helping to delay suffering and maintaining quality of life in patients with advanced prostate cancer. These are the goals that we are moving toward in cancer treatment. The treatment of advanced prostate cancer is undergoing a rapid transformation, and this drug is a key component of that transformation.”

The drug was developed by Janssen Research & Development, LLC and works by blocking the production of hormones produced by the cancer that stimulate its growth. The medication should be used with caution in individuals who have a history of fluid retention, high blood pressure, cardiovascular disease, and low blood potassium.

Written By Grace Rattue