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A Trial to Find Out if REGN5678 is Safe and How Well it Works Alone or in Combination With Cemiplimab for Adult Participants With Metastatic Castration-Resistant Prostate Cancer and Other Tumors

Phase 1
Recruiting
Conditions
Metastatic Castration-resistant Prostate Cancer (mCRPC)
Clear Cell Renal Cell Carcinoma (ccRCC)
Interventions
Registration Number
NCT03972657
Lead Sponsor
Regeneron Pharmaceuticals
Brief Summary

The main purpose of this study is to determine the safety, tolerability (how your body reacts to the drug) and effectiveness (ability to treat your cancer) of REGN5678 alone, or in combination with cemiplimab.

The study has 2 parts. The goal of Part 1 (dose escalation) is to determine a safe dose(s) of REGN5678 when it is given alone or in combination with cemiplimab. The goal of Part 2 (dose expansion) is to use the REGN5678 drug dose(s) found in Part 1 to see how well REGN5678 alone or in combination with cemiplimab works to shrink tumors.

This study is looking at several other research questions, including:

1. Side effects that may be experienced by taking REGN5678 alone or in combination with cemiplimab

2. How REGN5678 alone or in combination with cemiplimab works in the body

3. How much REGN5678 and/or cemiplimab are present in the blood

4. To see if REGN5678 alone or in combination with cemiplimab works to reduce the size of the tumor by helping the immune system destroy the tumor

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
Male
Target Recruitment
345
Inclusion Criteria

mCRPC cohorts:

  1. Men with histologically or cytologically confirmed adenocarcinoma of the prostate without pure small cell carcinoma.

  2. Prostate specific antigen (PSA) value at screening ≥4 ng/mL that has progressed within 6 months prior to screening as defined in the protocol.

  3. Has received ≥2 lines prior systemic therapy approved in the metastatic and/or castration-resistant setting (in addition to androgen deprivation therapy [ADT]) including at least:

    1. one second-generation anti-androgen therapy (eg, abiraterone, enzalutamide, apalutamide, or darolutamide)
    2. post-177Lu-PSMA-617 radiotherapy expansion cohort only. Must have received at least 2 doses of 177Lu-PSMA-617.

ccRCC cohorts:

  1. Men and women with histologically or cytologically confirmed RCC with a clear-cell component.
  2. Diagnosis of metastatic ccRCC with at least one measurable lesion via RECIST 1.1 criteria
  3. Has progressed on or after ≥1 line prior systemic therapy approved in the metastatic setting. Prior treatment must include an anti-programmed death-1 (receptor) [PD-1]/programmed death-ligand 1 (PD-L1) therapy and either ipilimumab and/or a tyrosine kinase inhibitor

Key

Exclusion Criteria
  1. Has received treatment with an approved systemic therapy within 3 weeks of dosing or has not yet recovered (ie, grade ≤1 or baseline) from any acute toxicities, as described in the protocol
  2. Has received any previous systemic biologic therapy within 5 half-lives of first dose of study therapy, as described in the protocol
  3. Has received prior PSMA-targeting therapy with the exception of approved radiopharmaceutical therapy (eg. 177Lu-PSMA-617) in mCRPC patients
  4. Dose Escalation: Has had prior anti-cancer immunotherapy (other than sipuleucel-T) within 5 half-lives prior to study therapy.
  5. Dose Expansion (mCRPC only): Has had prior anti-cancer immunotherapy, as describe in the protocol
  6. Any condition that requires ongoing/continuous corticosteroid therapy (>10 mg prednisone/day or anti-inflammatory equivalent) within 1 week prior to the first dose of study therapy
  7. Ongoing or recent (within 5 years) evidence of significant autoimmune disease that required treatment with systemic immunosuppressive treatments
  8. Encephalitis, meningitis, neurodegenerative disease (with the exception of mild dementia that does not interfere with activities of daily living [ADLs]) or uncontrolled seizures in the year prior to first dose of study therapy
  9. Uncontrolled infection with human immunodeficiency virus (HIV), hepatitis B or hepatitis C infection; or diagnosis of immunodeficiency

NOTE: Other protocol defined Inclusion/Exclusion Criteria apply

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
mCRPC - dose expansion cohortREGN5678Participants will receive the REGN5678 presumptive RP2D(s)
ccRCC - dose expansion cohortREGN5678Participants will receive the REGN5678 presumptive RP2D(s)
mCRPC - dose escalation cohortREGN5678Participants will receive REGN5678 monotherapy for presumptive recommended phase 2 dose(s) (presumptive RP2D) identification Note: Dose escalation on monotherapy lead-in of REGN5678 followed by combination therapy of REGN5678 with full dose cemiplimab is no longer actively enrolling new participants. The prophylactic use of sarilumab is no longer in use.
ccRCC - dose escalation cohortREGN5678Participants will receive REGN5678 monotherapy for presumptive RP2D identification Note: Dose escalation on monotherapy lead-in of REGN5678 followed by combination therapy of REGN5678 with full dose cemiplimab is no longer actively enrolling new participants. The prophylactic use of sarilumab is no longer in use.
mCRPC - dose escalation cohortCemiplimabParticipants will receive REGN5678 monotherapy for presumptive recommended phase 2 dose(s) (presumptive RP2D) identification Note: Dose escalation on monotherapy lead-in of REGN5678 followed by combination therapy of REGN5678 with full dose cemiplimab is no longer actively enrolling new participants. The prophylactic use of sarilumab is no longer in use.
ccRCC - dose escalation cohortCemiplimabParticipants will receive REGN5678 monotherapy for presumptive RP2D identification Note: Dose escalation on monotherapy lead-in of REGN5678 followed by combination therapy of REGN5678 with full dose cemiplimab is no longer actively enrolling new participants. The prophylactic use of sarilumab is no longer in use.
Primary Outcome Measures
NameTimeMethod
Incidence and severity of adverse event of special interests (AESIs)Through study completion, Up to 5 years

Dose Escalation Phase

Incidence and severity of serious adverse events (SAEs)Through study completion, Up to 5 years

Dose Escalation Phase

ORR per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteriaThrough study completion, Up to 5 years

Dose Expansion Phase - ccRCC cohort

Number of participants with Grade ≥3 laboratory abnormalitiesThrough study completion, Up to 5 years

Dose Escalation Phase

Objective response rate (ORR) per modified Prostate Cancer Working Group 3 (PCWG3) criteriaThrough study completion, Up to 5 years

Dose Expansion Phase - mCRPC cohort

Incidence and severity of treatment-emergent adverse events (TEAEs)Through study completion, Up to 5 years

Dose Escalation Phase

Concentration of REGN5678 in serum over timeThrough study completion, Up to 5 years

Dose Escalation Phase

Incidence of dose-limiting toxicities (DLTs)First dose through day 42 of last participant in each dose level

Dose Escalation Phase

Concentration of REGN5678 in combination with cemiplimab in serum over timeThrough study completion, Up to 5 years

Dose Escalation Phase

Secondary Outcome Measures
NameTimeMethod
Concentration of REGN5678 in combination with cemiplimab in serum over timeThrough study completion, Up to 5 years

Dose Expansion Phase

Presence or absence of antibodies against REGN5678Through study completion, Up to 5 years

Dose Escalation and Dose Expansion Phases

ORR per RECIST 1.1 criteriaThrough study completion, Up to 5 years

Dose Escalation Phase - ccRCC cohort

ORR based upon prostate specific antigen (PSA) responseThrough study completion, Up to 5 years

Dose Escalation and Dose Expansion Phases - mCRPC cohorts

Presence or absence of antibodies against cemiplimabThrough study completion, Up to 5 years

Dose Escalation and Dose Expansion Phases

Incidence and severity of AESIsThrough study completion, Up to 5 years

Dose Expansion Phase

ORR per modified PCWG3 criteriaThrough study completion, Up to 5 years

Dose Escalation Phase - mCRPC cohort

Concentration of REGN5678 in serum over timeThrough study completion, Up to 5 years

Dose Expansion Phase

Incidence and severity of TEAEsThrough study completion, Up to 5 years

Dose Expansion Phase

Incidence and severity of SAEsThrough study completion, Up to 5 years

Dose Expansion Phase

Percentage of participants with ≥90% decline of PSAThrough study completion, Up to 5 years

Dose Escalation and Dose Expansion Phases- mCRPC cohorts

Number of participants with grade ≥3 laboratory abnormalitiesThrough study completion, Up to 5 years

Dose Expansion Phase

Trial Locations

Locations (17)

University of Arizona

🇺🇸

Tucson, Arizona, United States

John Wayne Cancer Institute (JWCI)

🇺🇸

Santa Monica, California, United States

Sarah Cannon Research Institute (SCRI)

🇺🇸

Denver, Colorado, United States

Yale University Hospital

🇺🇸

New Haven, Connecticut, United States

Banner MD Anderson Cancer Center

🇺🇸

Gilbert, Arizona, United States

Moffitt Cancer Center - McKinley Drive

🇺🇸

Tampa, Florida, United States

Icahn School of Medicine at Mount Sinai

🇺🇸

New York, New York, United States

Columbia University - The Trustees of Columbia University in the City of New York

🇺🇸

New York, New York, United States

Oregon Health & Science University (3485 S. Bond)

🇺🇸

Portland, Oregon, United States

Lifespan Cancer Institute

🇺🇸

Providence, Rhode Island, United States

MD Anderson Cancer Center

🇺🇸

Houston, Texas, United States

Emily Couric Clinical Cancer Center

🇺🇸

Charlottesville, Virginia, United States

Massachusetts General Hospital

🇺🇸

Boston, Massachusetts, United States

NYU Langone Health Perlmutter Cancer Center

🇺🇸

New York, New York, United States

Montefiore Medical Center

🇺🇸

New York, New York, United States

Providence Portland Medical Center

🇺🇸

Portland, Oregon, United States

Thomas Jefferson University Hospital

🇺🇸

Philadelphia, Pennsylvania, United States

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