Enzalutamide With or Without Vaccine Therapy for Advanced Prostate Cancer

Clinical Trial Summary

Background: - Enzalutamide is a hormone therapy that is used to treat advanced prostate cancer. It is given after chemotherapy and surgery to help the body destroy the cancer cells. A new possible way of treating prostate cancer is using a vaccine that may help stimulate the immune system. It will help white blood cells recognize and kill the cancer cells in and around the prostate. Researchers want to see whether this vaccine, given with enzalutamide, is more effective at treating advanced prostate cancer than enzalutamide alone. Objectives: - To compare the safety and effectiveness of enzalutamide with and without vaccine therapy for advanced prostate cancer. Eligibility: - Men at least 18 years of age who have advanced castration-resistant prostate cancer. Design: - Participants will be screened with a physical exam and medical history. Blood and urine samples will be collected. Imaging studies will be used to monitor the cancer before treatment. - Participants will be separated into two groups. One group will have enzalutamide and the study vaccine. The other group will have enzalutamide alone. - All participants will take enzalutamide once a day. They will take the drug during 4-week cycles of treatment. - Treatment will be monitored with frequent blood tests and imaging studies. Participants will continue to take the study drug for as long as the cancer does not grow, and the side effects are not severe. - The vaccine group of participants will also have the new study vaccine. They will have a single injection on the first day of the first study cycle. There will be regular booster injections afterward. There will be one on day 15 of the first cycle, the first day of the second cycle. The vaccine will then be given every 4 weeks for the next four cycles, and then every 12 weeks (every 3 cycles) thereafter. Participants will continue to have the study vaccine for as long as the cancer does not grow, and the side effects are not severe.

Background: - Enzalutamide is a well-tolerated, modern androgen receptor antagonist (ARA) with more enhanced anti-tumor activity compared to previous ARAs. Phase III trial has demonstrated a 4.8 month improvement in survival and a 37% risk reduction in death in metastatic castration resistant prostate cancer (mCRPC) patients who have had previous docetaxel. - PROSTVAC is a therapeutic cancer vaccine which is designed to induce an anti-tumor immune response. In a randomized controlled Phase 2 trial, PROSTVAC (rilimogene galvacirepvec/rilimogene glafolivec) therapy was associated with a prolongation of survival by 8.5 months in men with metastatic castrate-resistant prostate cancer. An international Phase 3 trial is on-going. - Preclinical data has demonstrated that hormonal therapies such as ARAs can enhance the immune response through multiple mechanisms. Specifically, our group has shown that enzalutamide can increase thymic production of na(SqrRoot) ve T-cells, which could be activated by a cancer vaccine. Together, these data provide an important rationale to combine enzalutamide with PSA-TRICOM in mCRPC. - Data from the clinical trials with these therapies suggest that they are very well tolerated and without overlapping toxicity. Objective: -Determine if prostate-specific antigen (PSA)-TRICOM combined with enzalutamide will increase time to progression (as defined by Prostate Cancer Clinical Trials Working Group 2 criteria, incorporated in section 5.2) in chemotherapy-naive metastatic castration resistant prostate cancer patients compared to enzalutamide alone. Design: - The study will randomize chemotherapy-naive, mCRPC patients to either enzalutamide alone or enzalutamide with PSA-TRICOM. Enzalutamide will be given at the standard dose of 160 mg daily. - PSA-TRICOM will be administered identical to the Phase III dosing with vaccine given week 1 (vaccinia-PSA-TRICOM, 2x10(8) units subcutaneously) and then week 3, 5 and then monthly fowlpox-vaccine (1x10(9) units subcutaneously). - After completing 6 months of vaccine, fowlpox-vaccine (1x10(9) units subcutaneously will be administered every 3 months. Patients will be treated until radiographic progression on scans using Prostate Cancer Working Group Criteria. Eligibility: - mCRPC patients with rising PSA or progressive disease despite castration levels of testosterone. - Chemotherapy-na(SqrRoot) ve with minimal or no symptoms related to prostate cancer. - Patients with history of autoimmune disease, brain/leptomeningeal metastasis, a second malignancy within 3 years of enrollment, or a severe co-morbid condition will be excluded. - Patients who have received abiraterone will be excluded - Patients will be stratified based on previous immunotherapy used as cancer treatment. ;

Study Design

Related Conditions & MeSH terms

• Prostate Cancer
• Prostatic Neoplasms