Antigen-presenting cells 8015 (Provenge) in patients with androgen-dependent, biochemically relapsed prostate cancer.

Abstract

BACKGROUND:

Antigen-presenting cells 8015 (APC8015; Provenge) is an immunotherapeutic product designed to initiate a T-cell-mediated immune response against prostatic acid phosphatase, an antigen overexpressed in 95% of prostate cancer cells. In phase I/II trials, APC8015 has shown immunologic and clinical responses in patients with androgen-independent prostate cancer. This phase II trial was conducted to assess the prostate-specific antigen (PSA)-modulating effects of APC8015 in patients with androgen-dependent prostate cancer (ADPC) with biochemical progression.

PATIENTS AND METHODS:

Patients with nonmetastatic recurrent disease as manifested by increasing PSA levels (0.4-6.0 ng/mL) and who had undergone previous definitive surgical or radiation therapy were enrolled. Therapy consisted of APC8015 infusion on weeks 0, 2, and 4 (ie, 3 infusions). Prostate-specific antigen was measured at baseline and monthly until disease progression, defined as a doubling of the baseline or nadir PSA value (whichever was lower) to > or = 4 ng/mL or development of distant metastases.

RESULTS:

Thirteen of 18 patients demonstrated an increase in PSA doubling time (PSADT), with a median increase of 62% (4.9 months before treatment vs. 7.9 months after treatment; P = 0.09; signed-rank test).

CONCLUSION:

Therapy was well tolerated. APC8015 as single-agent immunotherapy for patients with ADPC and biochemical progression did not result in > or = 50% decrease in PSA from baseline levels but did appear to modulate PSADT in some patients. Further manipulations of host immunity may be required to achieve a significant antitumor effect.

• Authors: Garth Beinart, Brian I Rini, Vivian Weinberg, Eric J Small
• Journal: Clinical prostate cancer (Clin Prostate Cancer) Vol. 4 Issue 1 Pg. 55-60 (Jun 2005) ISSN: 1540-0352 [Print] United States
• PMID: 15992463 (Publication Type: Clinical Trial, Journal Article)

Chemical References

• Prostate-Specific Antigen

Topics

• Adenocarcinoma (immunology, pathology, therapy)
• Aged
• Antigen-Presenting Cells
• Disease Progression
• Humans
• Immunotherapy (methods)
• Male
• Middle Aged
• Neoplasm Recurrence, Local
• Prostate-Specific Antigen (blood)
• Prostatic Neoplasms (immunology, pathology, therapy)