A Neoadjuvant Study of Androgen Ablation Combined With Cyclophosphamide and GVAX Vaccine for Localized Prostate Cancer

Phase 1

Completed

Conditions: Prostate Cancer Adenocarcinoma in Situ

Interventions: Drug: degarelix acetate
Drug: Cyclophosphamide
Drug: GVAX

Registration Number: NCT01696877

Lead Sponsor: Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins

Brief Summary: This research is being done to see if an investigational prostate cancer vaccine, called GVAX, can safely be given together with a single intravenous injection of a drug called cyclophosphamide to men that will undergo surgery to remove their cancerous prostate glands who have also received standard hormonal therapy.

Detailed Description: Cancer immunotherapy refers broadly to approaches which attempt to treat cancer by activating immune responses directed against malignant tissue. Prostate GVAX is an allogeneic cell-based prostate cancer vaccine composed of two irradiated cell lines (PC3 and LNCaP) that have been genetically modified to secrete granulocyte-macrophage colony-stimulating factor (granulocytemacrophage-colony stimulating factor). The release of granulocytemacrophage-colony stimulating factor by these modified tumor cells serves to recruit dendritic cells which then present tumor antigens to T-cells, thus initiating antitumor immune responses.

However, abundant preclinical data show that, when used alone, cell-based immunotherapy is unable to break specific T-cell tolerance in tumor-bearing hosts. Studies in an autochthonous prostate cancer mouse model have shown that giving low-dose cyclophosphamide prior to a cell-based granulocytemacrophage-colony stimulating factor-secreting vaccine abrogates immune tolerance through augmentation of CD8+ T cell infiltration in the prostate, transient depletion of regulatory T cells (Tregs), and increased expression of dendritic cell maturation markers. Enhancement of antitumor immunity has also been observed in other preclinical models where cyclophosphamide was given in sequence with granulocytemacrophage-colony stimulating factor-secreting immunotherapy for the treatment of breast and pancreatic cancers. These preclinical data are supported by early-phase clinical trials combining GVAX with low-dose cyclophosphamide in pancreatic and breast cancers.

Furthermore, emerging evidence suggests that androgen deprivation therapy (ADT) itself has profound effects on the host immune system, resulting in thymic regeneration and enhancement of antitumor immunity. In addition, preclinical and clinical studies demonstrate that ADT augments prostate cancer-specific immune responses induced by immunotherapy, suggesting that ADT may act synergistically with immunotherapy. Based on data from mouse models as well as human clinical trials, it has been suggested that prostate cancer immunotherapy may be most effective when administered in the setting of an androgen-suppressed environment.

Building on these findings, investigators have designed a study to assess the use of ADT given alone or administered following immunization with low-dose cyclophosphamide and prostate GVAX, in patients undergoing radical prostatectomy. Investigators aim (1) to determine whether ADT is immunogenic in men with localized prostate cancer by evaluating T-cell infiltration in harvested prostate glands; (2) to determine whether administering ADT after low-dose cyclophosphamide and prostate GVAX augments immune infiltration into the prostate gland; and (3) to investigate whether this combinatorial immuno-hormonal approach is safe and feasible. Investigators hypothesize that the combination of ADT and cyclophosphamide/GVAX will produce significantly greater antitumor immune responses than would ADT used alone.

Recruitment & Eligibility

Status: COMPLETED

Sex: Male

Target Recruitment: 29

Inclusion Criteria

Histologically confirmed adenocarcinoma of the prostate (clinical stage T1c-T3b, N0, M0) without involvement of lymph nodes, bone, or visceral organs
Initial prostate biopsy is available for central pathologic review, and is confirmed to show at least 2 positive cores and a maximum Gleason sum of ≥ 7
Radical prostatectomy has been scheduled at Johns Hopkins Hospital
Age ≥ 21 years
Eastern Cooperative Oncology Group performance status 0-1, or Karnofsky score ≥ 70%
Adequate bone marrow, hepatic, and renal function:
- White Blood Count > 3,000 cells/mm3
- Absolute neutrophil count > 1,500 cells/mm3
- Hemoglobin > 9.0 g/dL
- Platelet count > 100,000 cells/mm3
- Serum creatinine < 2.0 mg/dL
- Serum bilirubin < 2 mg/dL
- Alanine aminotransferase < 2 × upper limit of normal (ULN)
- Aspartate aminotransferase < 2 × ULN
- Alkaline phosphatase < 2 × ULN
Willingness to provide written informed consent and HIPAA authorization for the release of personal health information, and the ability to comply with the study requirements (note: HIPAA authorization will be included in the informed consent)
Willingness to use barrier contraception from the time of cyclophosphamide and/or GVAX administration until the time of prostatectomy.

Exclusion Criteria

Presence of known lymph node involvement or distant metastases
Other histologic types of prostate cancers such as ductal, sarcomatous, lymphoma, small cell, and neuroendocrine tumors
Prior radiation therapy, hormonal therapy, biologic therapy, or chemotherapy for prostate cancer
Prior immunotherapy/vaccine therapy for prostate cancer
Previous or concurrent use of cyclophosphamide
Concomitant treatment with other hormonal therapy or 5a-reductase inhibitors
Current use of systemic corticosteroids or use of corticosteroids within 4 weeks of enrollment (inhaled corticosteroids for asthma or Chronic obstructive pulmonary disease are permitted)
Use of experimental agents for prostate cancer within the past 3 months
Known allergy to cyclophosphamide or G-colony stimulating factor /granulocytemacrophage-colony stimulating factor
Known hypersensitivity to materials of bovine origin (e.g. fetal bovine serum), or other components of GVAX which include Dimethyl sulfoxide and hydroxyethyl starch as well as small amounts of porcine trypsin and DNase
History or presence of autoimmune disease requiring systemic immunosuppression (including but not limited to: inflammatory bowel disease, systemic lupus erythematosus, vasculitis, rheumatoid arthritis, scleroderma, multiple sclerosis, hemolytic anemia, Sjögren syndrome, and sarcoidosis)
Other concurrent malignancies, with the exception of non-melanoma skin cancers and superficial bladder cancer
Uncontrolled major active infectious, cardiovascular, pulmonary, hematologic, or psychiatric illnesses that would make the patient a poor study candidate
Known prior or current history of HIV and/or hepatitis B/C

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Cyclophosphamide, GVAX and Degarelix	degarelix acetate	Cyclophosphamide will be given at a dose of 200 mg/m2 as a single intravenous infusion. 1 day later, prostate GVAX will be administered as five 0.8-mL intradermal injections of PC3 (2.5 × 108 cells) and five 0.5-mL intradermal injections of LNCaP (2.5 × 108 cells), for a total dose of 5 × 108 cells. On day 14, Degarelix will be administered as three 80 mg subcutaneous injections, for a total dose of 240 mg.
Degarelix	degarelix acetate	Degarelix will be administered as three 80 mg subcutaneous injections, for a total dose of 240 mg at 14 (±3) days prior to surgery. A telephone follow-up interview (or an in-person clinic visit) to evaluate for adverse events will occur 28 (±21) days after prostatectomy. Patients will then be followed by their urologists according to standard institutional practices, but will require prostate-specific antigen evaluations every 3 (±1) months during year 1 and every 6 (±2) months during years 2-3.
Cyclophosphamide, GVAX and Degarelix	GVAX	Cyclophosphamide will be given at a dose of 200 mg/m2 as a single intravenous infusion. 1 day later, prostate GVAX will be administered as five 0.8-mL intradermal injections of PC3 (2.5 × 108 cells) and five 0.5-mL intradermal injections of LNCaP (2.5 × 108 cells), for a total dose of 5 × 108 cells. On day 14, Degarelix will be administered as three 80 mg subcutaneous injections, for a total dose of 240 mg.
Cyclophosphamide, GVAX and Degarelix	Cyclophosphamide	Cyclophosphamide will be given at a dose of 200 mg/m2 as a single intravenous infusion. 1 day later, prostate GVAX will be administered as five 0.8-mL intradermal injections of PC3 (2.5 × 108 cells) and five 0.5-mL intradermal injections of LNCaP (2.5 × 108 cells), for a total dose of 5 × 108 cells. On day 14, Degarelix will be administered as three 80 mg subcutaneous injections, for a total dose of 240 mg.

Primary Outcome Measures

Name	Time	Method
Intraprostatic CD8+ T Cell Infiltration	2 years	CD8+ T cell infiltration (quantified as log\[CD8 density\]) into the prostate from harvested prostate glands in men with localized prostate cancer receiving neoadjuvant Androgen deprivation therapy alone (2 weeks prior to surgery), or cyclophosphamide and GVAX followed by Androgen deprivation therapy, (with cyclophosphamide/GVAX administered 4 weeks prior to prostatectomy, and Androgen deprivation therapy administered 2 weeks prior to prostatectomy).

Secondary Outcome Measures

Name	Time	Method
Quantification of Tissue Androgen Concentrations	2 years	Tissue androgen concentrations (testosterone, dihydrotestosterone), and androgen receptor (AR) protein expression in prostate specimens
Percentage of Participants Without Prostate Specific Antigen Recurrence at 24 Months After Surgery	2 years	Percentage of participants in each arm who were free of prostate specific antigen recurrence (i.e. prostate specific antigen remained undetectable after prostatectomy) at 24 months after undergoing surgery.
Intraprostatic CD4+ T Cell and Treg Infiltration	2 years	Number of participants with CD4+ T cell and Treg infiltration into the prostate.
Quantification of Markers of Apoptosis	2 years	Amount of apoptosis (activated caspase 3) and proliferation (Ki-67) in prostate tumor specimens
Pathological Complete Responses	2 years	Number of participants with pathological complete response (pCR)
Serum Antibodies to Prostate-associated Antigens	2 years	Number of participants with generation of novel antibodies to prostate-associated antigens in the serum of patients, after the initiation of protocol therapy
Prostate-specific Antigen Response Rate	2 years	Number of participants with Prostate-specific antigen response