NCT03541928

Phase II High Risk Prostate Cancer Trial Using Gene & Androgen Deprivation Therapies, Radiotherapy, & Surgery

Phase II Study Evaluating HSV-tk + Valacyclovir Gene Therapy in Combination With Androgen Deprivation Therapy, Brachytherapy, External Beam Radiotherapy, and Prostatectomy for High-Risk Prostate Cancer

• Status: Unknown
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 60 (estimated)
• Sponsor: The Methodist Hospital Research Institute · Academic / Other
• Sex: Male
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This is a prospective phase II study to assess the efficacy and toxicity of HSV-tk+ valacyclovir gene therapy in combination with androgen deprivation therapy, brachytherapy, external beam radiotherapy, and prostatectomy in previously untreated high-risk prostate cancer.

Detailed description

This phase II study plans to assess efficacy and toxicity of HSV-tk+ valacyclovir gene therapy in combination with androgen deprivation therapy, brachytherapy, external beam radiotherapy, and prostatectomy in previously untreated high-risk prostate cancer patients. Clinical response as evaluated by changes in serum PSA level and digital rectal examination as well as by histological alterations on re-biopsy and prostatectomy such as the presence of apoptosis, necrosis, tumor proliferation and immunologic response, will be assessed following HSV-tk + valacyclovir treatment. Blood samples will be taken for systemic immunological response, blood counts and liver functions tests. Toxicity will be graded by the Common Terminology Criteria for Adverse Events (CTCAE) and Radiation Therapy Oncology Group (RTOG) neuro-toxicity scores (See Appendices). Additionally, patients will be followed closely to assess nadir PSA, freedom from PSA-progression, and freedom from local and distant progression and overall survival.

Conditions

• High-risk Prostate Cancer
• Prostate Cancer

Interventions

Type	Name	Description
DRUG	HSV-Tk	Injection of the HSV-tk gene therapy product in four quadrants of prostate to enhance the immune system via "bystander effect" in which cytotoxicity is conferred to non-transduced neighboring cells. In vivo bystander effects are likely due to a combination of host immunological responses and to gap junction-mediated transport of phosphorylated prodrug metabolites to surrounding cells.
DRUG	Valacyclovir	The recommended dose for this trial is 2 g orally t.i.d. for 14 days (day 1 to day 15 and days 31 to 45). This dose has been calculated to give a similar AUC as 10 mg/kg of intravenous acyclovir administered every 8 hours. This is the same dose regimen used in a previous phase I clinical trial of ADV/HSV-tk plus acyclovir and topotecan in patients with recurrent ovarian cancer.
DRUG	Bicalutamide	The recommended dose for Bicalutamide therapy in combination with an LHRH analogue is one 50 mg tablet once daily (morning or evening), with or without food. It is recommended that Bicalutamide be taken at the same time each day. The use of an oral antiandrogen with medical castration for the treatment of prostate cancer is referred to as combined androgen blockade (CAB). Compared with LHRH-agonist monotherapy, CAB with bicalutamide did not reduce overall QoL but provided an early improvement in QoL related to lower urinary tract symptoms and pain.
DRUG	Leuprolide Acetate	Leuprolide acetate 7.5 mg depot injection will be injected monthly for a total of 2 months.
RADIATION	Brachytherapy, External beam radiotherapy	On day 60, patient will undergo high dose rate (HDR) Brachytherapy. The patient will have 8-14 needle catheters inserted under ultrasound guidance. CT simulation and radiation treatment planning will be performed. The needle catheters will be connected to an HDR afterloader containing an Iridium 192 source. A single dose of 1250cGy will be delivered.
PROCEDURE	Radical prostatectomy	approximately 2-3 weeks after radiotherapy completion, patient will undergo radical retropubic prostatectomy. Use of laparoscopy or robotic assistance will be at the urologist's discretion. Lymph node dissection will be performed.

Timeline

• Start date: 2018-08-02
• Primary completion: 2023-07-01
• Completion: 2023-07-01
• First posted: 2018-05-31
• Last updated: 2021-04-06

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study