Pilot Immunotherapy Study of Combination Prostate Specific Membrane Antigen (PSMA) and T-cell receptor γ alternate reading frame protein (TARP) Peptide With Poly IC-LC Adjuvant in Human Leukocyte Antigens (HLA)-A2 (+) Patients With Elevated prostatic specific antigen (PSA) After Initial Definitive Treatment The purpose of the study is to see if the PSMA/TARP proteins in the vaccine, along with the Hiltonol, can arouse and train the immune system to kill the prostate cancer cells. Prostate cancer is the most common cancer and is the second leading cause of cancer deaths in U.S. males. It is curable when it is confined to the prostate (kept from spreading) using surgery or radiation treatments. In some patients the cancer can come back after these treatments. Treatment options for prostate cancer that comes back include procedures or medications which may have significant risks and side effects. Another plan is being looked at that uses the body's immune system to attack prostate cancer cells. A vaccine has been developed that has proteins found in prostate cancer cells. One of the proteins is called PSMA and the other is called TARP. In addition to these proteins, another substance called Poly IC-LC (Hiltonol) will be added to the vaccine to boost its ability to start the immune system.
Detailed Objectives: 1. Estimate the frequency of immunological efficacy of the vaccine by comparison of the in vitro enzyme-linked immunosorbent spot (ELISpot) test results, for each antigen (PSMA, TARP) from peripheral blood specimens collected during the periods of time defined as "before", "during" and "after" vaccination. 2. Study the safety and toxicity of varying doses of polypeptide vaccines: PSMA27-35-PSMA687-701 (VLAGGFFLLYRHVIYAPSSHNKYA) and TARP13-35 (LQLLKQSSRRLEHTFMFLRNFSL) administered with a fixed dose of Poly IC-LC (2 mg total/treatment) as adjuvant. 3. Describe the impact of the vaccine on the pattern of PSA change in 2 subsets of patients: with castrate testosterone; with non-suppressed testosterone level/not on hormone therapy. 4. Identify if there is a basis for selection of a dose of the PSMA and the TARP polypeptide vaccines for future phase II development of this vaccination strategy, considering the dose range tested.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
NONE
Enrollment
29
Peptide vaccine (PSMA and TARP peptide vaccine with Poly IC-LC adjuvant). Pilot study using three treatment arms of increasing peptide dose levels (100 mcg, 300 mcg, and 1 mg) with a fixed dose of Poly IC-LC as an adjuvant. Patients were randomly assigned to one of the 3 arms upon enrollment.
Administered subcutaneously, one 2 mg/ml vial,(divided into two equal portions for each injection site).
H. Lee Moffitt Cancer Center & Research Institute
Tampa, Florida, United States
Ponce School of Medicine
Ponce, Puerto Rico
Occurrence of Related Adverse Events - Grade 3 or Higher
Number of participants with related Grade 3 or higher adverse events. Establish the safety and toxicity of varying doses of polypeptide vaccines PSMA and TARP administered with a fixed dose of Poly IC-LC as an adjuvant.
Time frame: Up to 48 months
Number of Participants With Prostatic Specific Antigen (PSA) Doubling
Number of Participants Who Had a Doubling of the PSA or Proceeded to Another Therapy. Assess the impact of the vaccine on the pattern of PSA change in patients with castrate testosterone level and in patients with non-suppressed testosterone level not on hormone therapy.
Time frame: Up to 48 months
Number of Participants Who Did Not Have PSA Doubling
Number of participants who did not have a PSA doubling before their last study visit, median 458 days from baseline PSA (55-613).
Time frame: Up to 48 months
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