ECOG: The Eastern Cooperative Oncology  Group

E7897 ECOG Trial Results Summary


Title
PSA Vaccine Therapy to Treat Advanced Prostate Cancer (A Phase II Trial)

Sponsor
Eastern Cooperative Oncology Group through the NCI-sponsored Cancer Cooperative Group Program

Purpose of the Study
To evaluate the effectiveness of three different prostate-specific antigen (PSA) vaccine treatments in men with advanced prostate cancer. Vaccination with one or two different substances were studied to see if and to what extent they activate an immune response that may help the body fight the growth of tumor cells.

Results
All three vaccine treatments were well tolerated. There was no increase in PSA level in 45.3 percent of men in the study after 19.1 months. Cancer did not progress in 78.1 percent of participants during that time. Additional clinical trials of PSA vaccines in the treatment of advanced prostate cancer are supported by these results. The results of a follow-up review of the trial after four years further supported additional studies.

Conclusion
Based on these data two follow-up clinical trials have been developed. In the E9802 trial men with rising PSA after completing initial therapy for localized prostate cancer (similar to the patient population in E7897) will be vaccinated with a prim-boost poxvirus vaccine and will begin hormone therapy in the face of biochemical progression. This trial will attempt to determine the effects of combining vaccine and standard hormonal therapy in men with advanced prostate cancer. A randomized Phase III clinical trial comparing vaccine to placebo vaccine in men with androgen independent advanced prostate cancer (E1805) has also been planned. These studies are based on the initial results of E7897 and will contribute to our understanding of how best to administer vaccines in relation to hormonal manipulation and will determine clinical outcomes in a larger randomized clinical trial design.

Start Date
August 1999

Stop Date
September 2000

Number of Participating Patients
70

Eligibility Requirements
Study participants had been diagnosed with prostate cancer and had completed cancer treatment. Their levels of PSA had increased following treatment, indicating a high probability of a recurrence of cancer.

Study Design
Participants were randomly assigned to one of three treatment groups. One group received four injections of a vaccine called fowlpox-PSA alone. Another group received three injections of fowlpox-PSA followed by one of another vaccine called vaccinia-PSA. The third group received a single injection of vaccinia-PSA vaccine followed by three injections of fowlpox-PSA vaccine. Treatment was given every six weeks.

Side Effects
Most side effects were mild to moderate, including mild to moderate skin irritation at the injection site, muscle aches, and elevated blood sugar levels.

References
Kaufman HL, Wang W, Manola J, DiPaola RS, Ko Y, Sweeney CJ, Whiteside TL, Schlom J, Wilding G, Weiner LM. Phase II Randomized Study of Vaccine Treatment of Advanced Prostate Cancer (E7897): A Trial of the Eastern Cooperative Oncology Group. J Clin Oncol 2004 Jun 1;22(11):2122-32. (E7897) [Manuscript published 6/1/2004]

Kaufman, H.L., Wang, W., Manola, J., DiPaola, R., Ko, Y.-J., Williams, S.D., Whiteside, T.L., Schlom, J., and Weiner, L.M. Phase II prime/boost vaccination using poxviruses expressing PSA in hormone dependent prostate cancer: Follow-up clinical results from ECOG 7897 (abstract). American Society of Clinical Oncology 23:378s, 2005.

National Cancer Institute Patient Summary
http://www.cancer.gov/clinical_trials/view_clinicaltrials.aspx?version=patient&cdrid=67036

Reviewed by
Howard Kaufman, MD, Columbia University; Cheryl K. Rutledge, BSN, Indiana University Cancer Center; Mike Katz, ECOG Patient Representative

Released February 16, 2005 (Revised July 5, 2006)