Vaccination of prostatectomized prostate cancer patients in biochemical relapse, with autologous dendritic cells pulsed with recombinant human PSA.

This study was conducted in prostate cancer patients in biochemical relapse after radical prostatectomy, to assess the feasibility, safety, and immunogenicity of therapeutic vaccination with autologous dendritic cells (DCs) pulsed with human recombinant prostate-specific antigen (PSA) (Dendritophage-rPSA). Twenty-four patients with histologically proven prostate carcinoma and an isolated postoperative rise of serum PSA (>1 ng/ml to 10 ng/ml) after radical prostatectomy were included. The patients received nine administrations of PSA-loaded DCs by combined intravenous, subcutaneous, and intradermal routes over 21 weeks. Postbaseline blood tests were performed at months 1, 3, 6, 9, and 12 (PSA levels), at months 6 and 12 (circulating prostate cancer cells), at month 6 (anti-PSA IgG and IgM antibodies), and at up to eight time points before, during, and after immunization (PSA-specific T cells). Circulating prostate cancer cells detected in six patients at baseline were undetectable at 6 months and remained undetectable at 12 months. Eleven patients had a postbaseline transient PSA decrease on one to three occasions, predominantly occurring at month 1 (7 patients) or month 3 (2 patients). Maximum PSA decrease ranged from 6% to 39%. PSA decrease on at least one occasion was more frequent in patients with low Gleason score ( p=0.016) at prostatectomy and with positive skin tests at study baseline ( p=0.04). PSA-specific T cells were detected ex vivo by ELISpot for IFN-gamma in 7 patients before vaccination and in 11 patients after vaccination. Of the latter 11 patients, 5 had detectable T cells both before and during the vaccination period, 4 only during the vaccination period, while 2 patients could for technical reasons not be assessed prevaccination. No induction of anti-PSA IgG or IgM antibodies was detected. There were no serious adverse events or otherwise severe toxicities observed during the trial. Immunization with Dendritophage-rPSA was feasible and safe in this cohort of patients. An immune response specific for PSA could be detected in some patients. A notable effect was the disappearance of circulating prostate cells in all patients who were RT-PCR positive before vaccination.

Subcutaneous interleukin-2 and interferon alfa administration in patients with metastatic renal cell carcinoma: final results of SCAPP III, a large, multicenter, phase II, nonrandomized study with sequential analysis design--the Subcutaneous Administration Propeukin Program Cooperative Group.

PURPOSE: This outpatient multicenter trial tested the hypothesis that subcutaneous administration of an interleukin-2 (IL-2)/interferon alfa (IFN alpha) combination produces a response rate greater than 20% in patients with renal cell carcinoma (RCC). PATIENTS AND METHODS: Patients with metastatic RCC received a 12-week induction treatment with subcutaneous IL-2 (5 days/wk, 9 and 18 million U/d)/IFN alpha (3 days/wk, 6 million U/d). After evaluation, patients with objective response or stable disease were randomly assigned to maintenance treatment or short consolidation treatment. RESULTS: Lack of benefit was shown at the 12th sequential analysis, and the trial was closed. At the end of the induction period, 26 (21%) of 122 patients had objective responses (including six complete responses). Thirty-three patients (27%) developed severe toxicity requiring dose reductions, delayed treatment, or treatment termination. Survival rates at one, two, and four years were 63%, 38%, and 17%, respectively. Three-year survival was 20% in patients with two poor prognosis factors and 37% in patients with one or no poor prognosis factors (P =.016). Three-year survival was significantly better (P < 10-3) in patients with erythrocyte sedimentation rate less than 35 mm (43%) compared with those with 1-hour sedimentation rate greater than 35 mm (19%). CONCLUSION: This study confirms the importance of prognostic factors when initiating cytokine immunotherapy in patients with metastatic RCC and underlines the prognostic value of erythrocyte sedimentation rate before treatment initiation. Nonetheless, this subcutaneous IL-2/IFN alpha combination does not improve response rate or survival compared with subcutaneous IL-2 alone, although a definitive conclusion cannot be drawn in the absence of a randomized study comparing the two treatments.