The Safety and Tolerability of GT0918 in Subjects With mHSPC and mCRPC

Phase 2

Completed

Conditions: Metastatic Castrate Resistant Prostate Cancer (mCRPC)
Metastatic Hormone-Sensitive Prostate Cancer (mHSPC)

Brief Summary: This was a multiple-center, open-label, randomized, daily dose, two-sequence, expanded/phase II study in subjects with mHSPC or mCRPC who progressed after either abiraterone or enzalutamide treatment.

The objective of the study is to evaluate the safety and tolerability of proxalutamide and determine the RP2D for Ph III and/or other confirming studies.

Subjects will be randomized into the 2 treatment arms.

Detailed Description: This study is an open-label, randomized, expanded/phase II study in subjects with mHSPC or mCRPC who progressed after either abiraterone or enzalutamide. All subjects will be randomized to take 400 mg or 500 mg of GT0918 by oral administration once daily on an empty stomach (2-3 hours after a meal) for initial treatment of 6 months. Randomization of subjects will be stratified by prior therapy (abiraterone or enzalutamide).

Subjects will continue treatment with GT0918 (proxalutamide) at their assigned dose on an empty stomach until disease progression, intolerable toxicities (AEs), or withdrawn consent. A post-treatment period of 4 weeks will commence that concludes with an end-of-study visit.

Disease progression will be assessed by three methods over the duration of the study. Subjects will be assessed for biochemical (PSA) progression measured monthly, as well as radiographic progression by CT scan or/and bone progression by radionuclide bone scan every 12-weeks. Progressive disease will be considered on the occurrence of the first assessed progression event. Subjects with PSA progression only may continue the study until radiographic or bone progression at the discretion of the Investigator and with agreement by the sponsor or their authorized medical monitor.

Recruitment & Eligibility

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Arm && Interventions

Group	Intervention	Description
Arm 2: 500 mg/day of GT0918	GT0918	Group 1: Post enzalutamide failure Group 2: Post abiraterone failure
Arm 1: 400 mg /day of GT0918	GT0918	Group 1: Post enzalutamide failure Group 2: Post abiraterone failure

Primary Outcome Measures

Name	Time	Method
Evaluate the Safety and Tolerability of GT0918 and Select the RP2D for Future Clinical Trial Study.	Average of 24 weeks, up to a maximum of 30 weeks	To evaluate the safety and tolerability of GT0918 assessed by AEs, SAEs between 400 mg arm vs. 500 mg arm with mHSPC or mCRPC who failed either abiraterone or enzalutamide treatment The percetage of AE and SAE would be evaluated in subjects with mHSPC and to determine the recommended Phase II dose (RP2D) over 6 months or longer treatment

Secondary Outcome Measures

Name	Time	Method
Time to PSA Progression	24 weeks	Time to PSA Progression in 400mg group and 500mg group
The Percentage of Subjects Achieving a ≥50% Reduction in PSA at 12 Weeks and 24 Weeks	24 weeks	The percentage of subjects achieving a ≥50% reduction in PSA at 3 months (12 weeks) as compared to baseline (study entry) was determined.
PSA Maximum Change at 12 Weeks	24 weeks	The percentage of change of PSA from baseline at Week 12 was calculated. Maximum percentage change of PSA from baseline at any time was calculated.

Locations (9): G U Research Network
🇺🇸
Omaha, Nebraska, United States
Comprehensive Cancer Centers of Nevada
🇺🇸
Las Vegas, Nevada, United States
Greenville Health System
🇺🇸
Greenville, South Carolina, United States
University Cancer & Blood Center
🇺🇸
Athens, Georgia, United States
Norton Cancer Institute
🇺🇸
Louisville, Kentucky, United States
New York Cancer & Blood Specialists
🇺🇸
East Setauket, New York, United States
Chesapeake Urology Research Associates
🇺🇸
Towson, Maryland, United States
Gabrail Cancer Center Research
🇺🇸
Canton, Ohio, United States
Mary Crowley Cancer Research
🇺🇸
Dallas, Texas, United States