[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-study-detail:100658366":3},{"organization":4,"outcomesModule":7,"designInfo":50,"detailedDescription":49,"studyPopulation":49,"armGroups":56,"interventions":67,"overallOfficials":86,"centralContacts":90,"locations":49,"responsibleParty":96,"collaborators":49,"id":98,"slug":99,"hasResults":100,"nctId":101,"briefTitle":102,"officialTitle":103,"acronym":49,"eligibilityCriteria":104,"healthyVolunteers":100,"sex":105,"minAge":106,"maxAge":49,"enrollmentInfo":107,"targetDuration":49,"studyType":110,"phases":111,"briefSummary":114,"conditions":115,"keywords":118,"overallStatus":132,"whyStopped":49,"lastUpdateSubmitDate":133,"lastUpdatePostDateStruct":134,"startDateStruct":137,"completionDateStruct":139,"leadSponsor":141,"locationsCount":49},{"fullName":5,"class":6},"Regeneron Pharmaceuticals","INDUSTRY",{"primaryOutcomes":8,"secondaryOutcomes":23,"otherOutcomes":49},[9,13,16,18,20],{"measure":10,"description":11,"timeFrame":12},"Occurrence of Treatment Emergent Adverse Events (TEAEs)","Dose escalation","Up to 5 years",{"measure":14,"description":11,"timeFrame":15},"Occurrence of Dose-Limiting Toxicities (DLTs)","Up to 42 days",{"measure":17,"description":11,"timeFrame":12},"Occurrence of Serious Adverse Events (SAEs)",{"measure":19,"description":11,"timeFrame":12},"Occurrence of Adverse Events of Special Interests (AESIs)",{"measure":21,"description":22,"timeFrame":12},"Composite Response Rate (CRR) of ≥50% decline of prostate specific antigen (PSA) and\u002For confirmed radiographic response of complete response (CR) or partial response (PR)","Dose expansion",[24,26,28,30,32,35,37,39,41,43,45,47],{"measure":25,"description":11,"timeFrame":12},"(CRR) of ≥50% decline of prostate specific antigen (PSA) and\u002For confirmed radiographic response of complete response (CR) or partial response (PR)",{"measure":27,"description":22,"timeFrame":12},"Occurrence of TEAEs",{"measure":29,"description":22,"timeFrame":12},"Occurrence of SAEs",{"measure":31,"description":22,"timeFrame":12},"Occurrence of AESIs",{"measure":33,"description":34,"timeFrame":12},"Percentage of participants with ≥50% reduction in PSA confirmed by a second PSA test ≥3 weeks later","Dose Escalation and Dose Expansion",{"measure":36,"description":34,"timeFrame":12},"Percentage of participants with ≥90% reduction in PSA confirmed by a second PSA test ≥3 weeks later",{"measure":38,"description":34,"timeFrame":12},"REGN21353 serum concentrations",{"measure":40,"description":34,"timeFrame":12},"Nezastomig serum concentrations",{"measure":42,"description":34,"timeFrame":12},"Occurrence of Anti-Drug Antibodies (ADA) to REGN21353",{"measure":44,"description":34,"timeFrame":12},"Occurrence of ADA to nezastomig",{"measure":46,"description":34,"timeFrame":12},"Magnitude of ADA to REGN21353",{"measure":48,"description":34,"timeFrame":12},"Magnitude of ADA to nezastomig",null,{"allocation":51,"interventionModel":52,"interventionModelDescription":49,"primaryPurpose":53,"observationalModel":49,"timePerspective":49,"maskingInfo":54},"NON_RANDOMIZED","SEQUENTIAL","TREATMENT",{"masking":55,"maskingDescription":49,"whoMasked":49},"NONE",[57,63],{"label":58,"type":59,"description":49,"interventionNames":60},"Module 1: monotherapy","EXPERIMENTAL",[61,62],"Drug: REGN21353","Drug: Sarilumab Prophylaxis (Contingency)",{"label":64,"type":59,"description":49,"interventionNames":65},"Module 2: combination",[61,66,62],"Drug: Nezastomig",[68,73,78],{"type":69,"name":70,"description":71,"armGroupLabels":72,"otherNames":49},"DRUG","REGN21353","Administered per the protocol",[58,64],{"type":69,"name":74,"description":71,"armGroupLabels":75,"otherNames":76},"Nezastomig",[64],[77],"REGN5678",{"type":69,"name":79,"description":80,"armGroupLabels":81,"otherNames":82},"Sarilumab Prophylaxis (Contingency)","May be administered as pretreatment, per the protocol",[58,64],[83,84,85],"REGN88","SAR153191","KEVZARA®",[87],{"name":88,"affiliation":5,"role":89},"Clinical Trial Management","STUDY_DIRECTOR",[91],{"name":92,"role":93,"phone":94,"phoneExt":49,"email":95},"Clinical Trials Administrator","CONTACT","844-734-6643","clinicaltrials@regeneron.com",{"type":97,"investigatorFullName":49,"investigatorTitle":49,"investigatorAffiliation":49,"oldNameTitle":49,"oldOrganization":49},"SPONSOR","100658366","phase-1-regn21353-alone-or-in-combination-with-nezastomig-for-metastatic-castration-resistant-prostate-cancer-in-adult-participants-100658366",false,"NCT07850921","REGN21353 Alone or in Combination With Nezastomig for Metastatic Castration-Resistant Prostate Cancer in Adult Participants","Phase 1\u002F2 Trial of REGN21353 (a STEAP1xCD3 Bispecific Antibody) Administered Alone or in Combination With Nezastomig (a PSMAxCD28 Bispecific Antibody) in Participants With Metastatic Castration-Resistant Prostate Cancer (mCRPC)","Key Inclusion Criteria:\n\n1. Is male with histologically or cytologically confirmed adenocarcinoma of the prostate without pure small cell carcinoma\n2. Has metastatic castration-resistant prostate cancer with prostate-specific antigen value as described in the protocol and that has progressed within 6 months prior to screening\n3. Has received ≥2 lines of prior systemic therapy approved in the metastatic and\u002For castration-resistant setting (in addition to androgen deprivation therapy) including at least one androgen receptor pathway inhibitor (eg, abiraterone, enzalutamide, apalutamide, or darolutamide)\n4. Has had either orchiectomy or be on luteinizing hormone-releasing hormone (LHRH) agonist or antagonist therapy with serum testosterone levels as described in the protocol and agree to stay on LHRH agonist or antagonist therapy during the trial\n5. Is able and willing to provide tumor tissue, either archival or newly obtained\n6. Has an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1\n7. Has adequate organ, bone marrow, renal and hepatic function\n\nKey Exclusion Criteria:\n\n1. Has not recovered (ie, grade ≤1 or baseline) from immune-mediated adverse event within 3 months prior to initiation of trial intervention therapy except for endocrinopathies adequately managed with hormone replacement\n2. Has permanently discontinued anti-cancer immune modulating therapies due to immune-mediated adverse events\n3. Has another malignancy that is progressing or requires active treatment, except non-melanoma skin cancer that has undergone potentially curative therapy or any tumor that has been deemed to be effectively treated with definitive local control\n4. Has ongoing or recent (within 5 years) evidence of significant autoimmune disease (including any history of systemic vasculitis) that required treatment with systemic immunosuppressive treatments\n5. Has active liver metastases\n6. Has current evidence of or history of central nervous system metastases as described in the protocol\n7. Has encephalitis, meningitis, neurodegenerative disease (with the exception of mild dementia that does not interfere with activities of daily living), or uncontrolled seizures in the year prior to first dose of trial intervention\n8. Has a known history of, or any evidence of, interstitial lung disease or active, noninfectious pneumonitis (past 5 years). A history of radiation pneumonitis in the radiation field is permitted\n9. Has active or recent infection requiring hospitalization or treatment with intravenous anti-infectives within 2 weeks of first dose of trial intervention\n10. Has significant cardiovascular disease\n\nNote: Other protocol defined Inclusion\u002F Exclusion criteria apply","MALE","18 Years",{"count":108,"type":109},192,"ESTIMATED","INTERVENTIONAL",[112,113],"PHASE1","PHASE2","This study will test an experimental Regeneron drug called REGN21353 (\"study drug\") to see if it can help treat previously treated prostate cancer that has spread (also called metastatic castration-resistant prostate cancer or mCRPC). Some participants may get additional experimental drugs in combination with REGN21353. These additional drugs are nezastomig and sarilumab. \"Experimental\" means that the drugs are being tested and have not been approved for use in prostate cancer by a country's national health agency that gives approval for new medicines to be prescribed.\n\nThe study is looking at:\n\n* What is the best dose of REGN21353 alone and together with nezastomig for treating prostate cancer\n* What side effects REGN21353 alone and together with nezastomig might cause\n* How well REGN21353 alone and together with nezastomig works\n* How much REGN21353 alone and together with nezastomig is in the blood at different times\n* If the body reacts to REGN21353 alone or together with nezastomig, in a way that may cause them to not work as well\n* How REGN21353 alone and together with nezastomig could affect prostate cancer, which can help researchers understand why REGN21353 alone or together with nezastomig work better in some than others",[116,117],"Metastatic Castration-Resistant Prostate Cancer","mCRPC",[119,120,121,122,123,124,125,126,127,128,129,130,131],"Prostate cancer","Metastatic prostate cancer","Castration resistant prostate cancer","Advanced prostate cancer","Stage 4 prostate cancer","Prostate cancer that has spread","Hormone refractory prostate cancer","Androgen-resistant prostate cancer","Androgen-independent prostate cancer","PSA progression","Androgen receptor pathway inhibitor (ARPI)","Luteinizing hormone-releasing hormone (LHRH)","Androgen deprivation therapy (ADT)","NOT_YET_RECRUITING","2026-09-23",{"date":135,"type":136},"2026-09-30","ACTUAL",{"date":138,"type":109},"2027-06-28",{"date":140,"type":109},"2031-07-28",{"name":5,"class":6}]