[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"trial:NCT05435495":3,"trial-entities:NCT05435495":117,"trial-summary:NCT05435495":122},{"id":4,"nct_id":4,"org_study_id":5,"brief_title":6,"official_title":7,"overall_status":8,"completion_date":9,"status_verified_date":10,"last_update_date":11,"start_date":12,"sponsor_name":13,"lead_sponsor_class":14,"has_dmc":15,"brief_summary":16,"detailed_description":17,"conditions":18,"keywords":20,"study_type":22,"primary_purpose":23,"phases":24,"enrollment_info":25,"interventions":28,"primary_outcomes":47,"secondary_outcomes":55,"sex":56,"minimum_age":57,"maximum_age":23,"healthy_volunteers":15,"eligibility_criteria":58,"std_ages":62,"locations":65,"central_contacts":110,"overall_officials":113,"references":115,"see_also_links":116},"NCT05435495","19553","Mechanisms of Resistance to PSMA Radioligand Therapy","Mechanisms of Resistance to PSMA Radioligand Therapy: Radiation Resistance Versus Dose","RECRUITING","2026-12-31","2026-03","2026-03-18","2021-10-21","University of California, San Francisco","OTHER",false,"This is a multicenter, correlative study to existing Lutetium based prostate-specific membrane antigen (PSMA)-targeted radioligand therapy (RLT) trials and uses.","PRIMARY OBJECTIVES:\n\nI. To determine the relationship between whole body tumor absorbed dose and response Lutetium based prostate-specific membrane antigen-targeted radioligand therapy (177Lu-PSMA-RLT).\n\nII. To determine the relationship between Post-Operative Radiation Therapy Outcomes Score (PORTOS) score and response to 177Lu-PSMA-RLT.\n\nIII. To determine the relative importance of radiation dose (whole body tumor absorbed dose) and radiation sensitivity (PORTOS score) as a marker of response to 177Lu-PSMA-RLT.\n\nEXPLORATORY OBJECTIVES:\n\nI. To develop novel signature of radiation sensitivity.\n\nII. To evaluate tumor biopsies to understand mechanisms of resistance.\n\nIII. To understand utility of post-cycle 4 single-photon emission computed tomography (SPECT\u002FCT) to evaluate treatment response.\n\nStudy participants will undergo a biopsy and blood draw prior to the initiation of planned therapy, as well as SPECT\u002FCT imaging performed after the first and fourth treatments. One SPECT\u002FCT scan will be performed 24 (+\u002F- 6) after the first treatment, and after the fourth treatment, a 24 +\u002F- 6-hour post-treatment SPECT\u002FCT will be performed. Additionally, study participants may choose to undergo optional biopsy and blood draw at time of progression.",[19],"Prostate Cancer",[21],"Radioligand Therapy","OBSERVATIONAL",null,[],{"count":26,"type":27},125,"ESTIMATED",[29,37,41],{"type":30,"name":31,"description":32,"armGroupLabels":33,"otherNames":35},"PROCEDURE","Single-photon emission computed tomography","Imaging procedure",[34],"Participants undergoing 177Lu-PSMA-617 treatment",[36],"SPECT\u002FCT",{"type":30,"name":38,"description":39,"armGroupLabels":40},"Blood Draw","Blood draw for future research tests (45-60 mL).",[34],{"type":30,"name":42,"description":43,"armGroupLabels":44,"otherNames":45},"Tumor Biopsy","Guided biopsy of lesion",[34],[46],"Biopsy",[48,52],{"measure":49,"description":50,"timeFrame":51},"Mean whole body tumor absorbed dose (WB Dose) across all metastatic lesions","The unit density sphere model will be implemented using OLINDA, a second-generation personal computer software for internal dose assessment in nuclear medicine to measure mean dose across all metastatic lesions. This approach uses the three time-point SPECT\u002FCTs to create a whole-body dose map, which can then be segmented. Using OLINDA, the total dose to each tumor will be calculated as the integral of activity over time estimated out to 500 hours. Dose will be calculated in gray (Gy).","Up to 6 months",{"measure":53,"description":54,"timeFrame":51},"Median PORTOS score","PORTOS is a gene signature that predicts salvage radiation success. A PORTOS score of zero (called a \"low\" PORTOS) means it predicts no benefit from salvage radiotherapy. A PORTOS greater than zero (called a \"high\" PORTOS score) predicts a benefit from salvage radiation.",[],"ALL","18 Years",{"inclusion":59,"exclusion":60,"raw_text":61},[],[],"Inclusion Criteria:\n\n1. Initiating treatment with Lutetium based PSMA-targeted RLT.\n2. Participants must have a PSMA-avid lesion that is accessible to biopsy. Biopsy of newly emerging radiographic metastases is desired and preferable to the biopsy of previously existing lesions whenever possible. Newly emerging lesions are defined as those that are absent on a previous scan, or those demonstrating unequivocal progression since initiation of the last treatment. Biopsies will be performed according to local institutional standards.\n3. Patients on warfarin, aspirin, or other anti-coagulants are eligible provided they are deemed able to tolerate discontinuation of anti-coagulation for at least five days prior to the biopsy. Conversion to low molecular weight heparin prior to biopsy is permitted per local standard operating procedures, provided there is approval by the interventional radiologist or the PI.\n4. Age \\>=18 years.\n5. Ability to understand and the willingness to sign a written informed consent document.\n\nExclusion Criteria:\n\n1. Patients with significant congenital or acquired bleeding disorders (eg von Wildebrand's disease, acquired bleeding factor inhibitors).\n2. Patients who are not able to undergo additional study related imaging procedures.",[63,64],"ADULT","OLDER_ADULT",[66,81,98],{"facility":67,"status":8,"city":68,"state":69,"zip":70,"country":71,"contacts":72,"geoPoint":78},"University of California, Los Angeles","Los Angeles","California","90095","United States",[73,76],{"name":74,"role":75},"Johannes Czernin, MD","PRINCIPAL_INVESTIGATOR",{"name":77,"role":75},"Matthew Rettig, MD",{"lat":79,"lon":80},34.05223,-118.24368,{"facility":13,"status":8,"city":82,"state":69,"zip":83,"country":71,"contacts":84,"geoPoint":95},"San Francisco","94143",[85,90,93],{"name":86,"role":87,"phone":88,"email":89},"Maya Aslam","CONTACT","415-514-8987","Maya.Aslam@ucsf.edu",{"role":87,"phone":91,"email":92},"877-827-3222","cancertrials@ucsf.edu",{"name":94,"role":75},"Thomas Hope, MD",{"lat":96,"lon":97},37.77493,-122.41942,{"facility":99,"status":8,"city":100,"state":100,"zip":101,"country":71,"contacts":102,"geoPoint":107},"Memorial Sloan Kettering","New York","10065",[103,105],{"name":104,"role":75},"Lisa Bodei, MD",{"name":106,"role":75},"Michael Morris, MD",{"lat":108,"lon":109},40.71427,-74.00597,[111],{"name":86,"role":87,"phone":112,"email":89},"(415) 514-8987",[114],{"name":94,"affiliation":13,"role":75},[],[],{"nct_id":4,"conditions":118,"biomarkers":120},[119],"Prostate Carcinoma",[121],"FOLH1 Gene",{"nct_id":4,"found":123,"summary":124,"prompt_version":134},true,{"design":125,"status":126,"heading":127,"summary":128,"follow_up":129,"word_count":130,"commitments":131,"compensation":132,"drugs_mentioned":133},"This is an observational study, meaning researchers will collect information without giving new treatments. It aims to enroll 125 participants.","completed","Understanding Resistance to Lutetium-based PSMA Radioligand Therapy for Prostate Cancer","This study is looking at why Lutetium-based PSMA-targeted radioligand therapy (RLT) might stop working for some people with prostate cancer. Researchers want to understand the relationship between the amount of radiation absorbed by tumors (whole body tumor absorbed dose) and how well the treatment works. They also want to see if a score called PORTOS (Post-Operative Radiation Therapy Outcomes Score) can predict treatment response. You could be eligible if you are starting Lutetium-based PSMA-targeted RLT and have a PSMA-avid lesion (a spot that shows up on a PSMA scan) that can be biopsied. The study aims to enroll 125 participants. The current recruitment status is unclear.","The primary endpoints, which measure the study's success, are tracked for up to 6 months.",106,"You will have a biopsy and blood draw before starting treatment, and SPECT\u002FCT imaging after your first and fourth treatments. You may also choose to have an optional biopsy and blood draw if your cancer progresses.","Not stated in the trial record.",[],"v2"]