Doctors have developed a successful new treatment for prostate cancer that slows down the condition and helps patients avoid relapse and live longer. The fantastic new result was possible by adding a drug called abiraterone acetate (zytiga) to a standard hormone therapy.
The result is based on a clinical trial of almost 2,000 people. It shows that adding abiraterone lowered the relative risk of death by 37 percent and the 3-year survival rate to 83 percent from 76 percent based on the standard therapy alone.
The study was presented at the 2017 American Society of Clinical Oncology Annual meeting by lead author Professor Nicholas James from the Queen Elizabeth Hospital in Birmingham, UK.
“Abiraterone not only prolonged life, but also lowered the chance of relapse by 70% and reduced the chance of serious bone complications by 50%,” Professor James said in a statement. “We believe that the upfront care for patients newly diagnosed with advanced prostate cancer should change.”
The combined therapies fight the production of testosterone around the body. Testosterone stimulates the growth of prostate cancer cells so the standard treatment, known as androgen deprivation therapy (ADT), acts on the testicles and stops the production of hormones. Unfortunately, other organs, including the prostate glands, continue to produce small quantities of testosterone and this is where abiraterone comes in. The substance target the enzyme that produces testosterone and similar hormones everywhere.
The patients were followed up on average 40 months after the two types of treatment started. According to the study, over that time 262 deaths occurred in the group using standard therapy and 184 in the group using abiraterone. Of these deaths, two in the abiraterone group and one in the standard were due to the treatment.
While the therapy is promising in term of survival rate, abiraterone had more severe side effects than the standard approach. Forty-one percent of patients complained of severe side effects when taking abiraterone, compared to 29 percent from the standard group. Side effects included cardiovascular and liver problems.
Previous studies showed successful results in fighting a particularly aggressive form of prostate cancers by using a mixture of hormonal therapy and a chemotherapy drug known as docetaxel. There is a chance that some patients might benefit by including abiraterone into the mix but more studies are necessary to confirm that. The team is currently planning molecular analysis of tissue samples from patients that could benefit from the new cocktail but, for now, it’s too early to tell.