Sipuleucel-T and Low-protein Diet in Patients With Metastatic Castrate-resistant Prostate Cancer

Not Applicable

Completed

Brief Summary: This is a single-center, randomized, open-label study to assess the feasibility of a low-protein diet intervention in patients with metastatic castrate-resistant prostate cancer (CRPC) who are receiving treatment with sipuleucel-T. Subjects will be randomized (1:1 ratio) to either Arm 1 or Arm 2 (Fig. 1).

Arm 1: Subjects randomized to Arm 1 will be treated with sipuleucel-T infusion on Day 1, every two weeks for a total of three infusions. Subjects on this arm will receive a control diet containing 20% protein.

Arm 2: Subjects randomized to Arm 2 will be treated with sipuleucel-T infusion on Day 1, every two weeks for a total of three infusions. Subjects on this arm will receive a low-protein diet containing 10% protein.

Patients with metastatic, asymptomatic or minimally symptomatic CRPC that has progressed despite androgen deprivation therapy will be eligible for the study. After informed consent eligible patients will be scheduled to receive sipuleucel-T (three infusions two weeks apart) with normal-protein diet vs. low-protein diet. Each cycle will be every 14 days. Diet intervention will commence 1 week prior to the first apheresis (Day -7) and will continue until 10 days after the last infusion of sipuleucel-T (Day +42) (Fig. 2).

Detailed Description: Primary Objective To assess the feasibility of low-protein diet intervention in patients with metastatic CRPC receiving immunotherapy with sipuleucel-T. Change in blood urea nitrogen (BUN) and urine urea nitrogen (UUN) from baseline to 6 weeks will be measured to assess adherence of following the diet intervention. The expected changes (mean, standard deviation) in BUN are 5.5 ± 2.6 mg/dL with 10% protein diet arm and 2.5 ± 2.6 mg/dL with 20% protein diet arm (please see section 12.5.7).

Secondary Objectives

1. To assess whether low-protein diet intervention augments the immune response to sipuleucel-T in men with metastatic CRPC.

2. To assess the safety and tolerability of the combination of sipuleucel-T and low-protein diet intervention.

3. To obtain preliminary evidence of clinical efficacy of the combination of sipuleucel-T and low-protein diet compared to sipuleucel-T and control-diet, including objective response rate (partial + complete response), progression-free survival (PFS) and overall survival (OS), and changes in prostate-specific antigen (PSA).

Recruitment & Eligibility

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Arm && Interventions

Group	Intervention	Description
Low protein diet arm	Low protein diet	10% protein content
Control protein diet arm	Control protein diet	20% protein content

Primary Outcome Measures

Name	Time	Method
Adherence to diet intervention	6 weeks	BUN and UUN laboratory values

Secondary Outcome Measures

Name	Time	Method
Feasibility of diet intervention	6 weeks	Rate of enrollment
Safety and tolerability of diet intervention combined with sipuleucel-T treatment	6 weeks	Rate of adverse events per CTCAE
Overall survival	2 years	Length of time start of treatment that patients are still alive
Rate of immune response	6, 12, and 14 weeks	IFN-γ ELISpot specific for PA2024 laboratory values
Progression free survival	2 years	Length of time during and after the treatment that a patient lives with the disease but it does not get worse

Locations (2): Indiana University Hospital
🇺🇸
Indianapolis, Indiana, United States
Indiana University Melvin and Bren Simon Cancer Center
🇺🇸
Indianapolis, Indiana, United States