Immunotherapy With N 803, ETBX-071, and M-CENK in Combination With Radiation for Participants With High-Risk Prostate Cancer.

NCT06765954 | Withdrawn Phase 2 FDA Drug

• 1 other identifier: ResQ110B-PROS
• Study Type: interventional
• Target: N/A
• Locations: 0 countries
• Sites: N/A

Brief Summary

This study tests a new treatment for men with high-risk prostate cancer who can't have surgery. The treatment combines three experimental drugs and radiation therapy. Researchers will track how well the treatment works and how safe it is. The study will last about five years.

Conditions

High-risk Prostate Cancer

Keywords

high-risk prostate cancer; Prostate Cancer; N-803; ETBX-071; M-CENK; Radiation Therapy/EBRT; Combination Therapy

Outcome Measures

Primary Outcomes (2)

• Complete Pathologic Response (CPR) after pre-radiation immunotherapy.

  Complete Pathologic Response (CPR) after pre-radiation immunotherapy: Assesses the complete absence of cancer in tissue samples taken after the pre-radiation immunotherapy phase. This signifies a complete eradication of the cancer at that stage of the treatment process.

  CPR: Assessed within approximately 6 weeks of study start.

• PSA30 response at end-of-treatment (EOT) after post-radiation immunotherapy

  Measures a ≥30% reduction in Prostate-Specific Antigen (PSA) levels from baseline to the end of treatment. PSA is a common biomarker used to monitor prostate cancer treatment success. A decrease in PSA suggests successful treatment in reducing the cancer burden.

  Assessed at EOT, which occurs roughly 30 to 39 weeks after the study begins.

Secondary Outcomes (3)

• Clinical Pathologic Response (after pre-radiation immunotherapy)

  Within approximately 6 weeks of the study start.

• Time to Recurrence Interval (TTRI)

  Variable, ranging from the end of radiation therapy (around 2-9 weeks after pre-radiation immunotherapy, depending on individual schedules) to up to 5 years (260 weeks).

• Safety (AEs and SAEs)

  Continuous monitoring throughout the entire study duration (approximately 303 weeks).

Other Outcomes (6)

• Quality of Life (QoL)

  Approximately 5 years

• Sexual Function

  Approximately 13 Months

• Changes in Immune Subsets and Antigen-Specific Immune Responses

  Approximately 13 Months

Study Arms (1)

Standard of care + Radiation therapy

EXPERIMENTAL

Combination of N-803, ETBX-071, and M-CENK, along with radiation therapy.

Drug: N-803 (IL-15 Superagonist); Drug: ETBX-071 (PSA-based Oncolytic Virus); Drug: M-CENK (Activated NK Cells); Radiation: External Beam Radiation Therapy (EBRT); Radiation: Androgen Deprivation Therapy (ADT); Radiation: Post-radiation immunotherapy

Interventions

N-803 (IL-15 Superagonist) DRUG

Administered subcutaneously (SC) both before and after radiation therapy. The specific dosing schedule varies slightly depending on the cohort.

Standard of care + Radiation therapy

M-CENK (Activated NK Cells) DRUG

Administered intravenously (IV) before and after radiation therapy, also with variations in the timing and dosing across different cohorts.

Standard of care + Radiation therapy

ETBX-071 (PSA-based Oncolytic Virus) DRUG

Administered subcutaneously (SC) before and after radiation therapy. The specific dosing schedule varies slightly depending on the cohort.

Standard of care + Radiation therapy

External Beam Radiation Therapy (EBRT) RADIATION

This is a standard treatment administered to all participants. The specific dose and schedule (40 Gy in 5 fractions over 2 weeks or up to 9 weeks) are determined by the investigator based on clinical judgment.

Standard of care + Radiation therapy

Androgen Deprivation Therapy (ADT) RADIATION

May be used in conjunction with the other therapies. The specific type and duration of ADT are at the investigator's discretion, and it may be initiated up to 6 months after the completion of radiotherapy. This treatment is not part of the experimental treatment regimen.

Standard of care + Radiation therapy

Post-radiation immunotherapy RADIATION

The post-radiation immunotherapy phase in the ResQ110B-PROS study involves the continued administration of N-803, ETBX-071, and M-CENK, but with a specific schedule and after the completion of radiation therapy.

Standard of care + Radiation therapy

Eligibility Criteria

• Age: 18 Years+
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age: ≥18 years old.
• Ability to understand and provide informed consent: Participants must be able to understand the study and provide written informed consent fulfilling all relevant Institutional Review Board (IRB) or Independent Ethics Committee (IEC) guidelines.
• Histologically confirmed prostate adenocarcinoma: A diagnosis confirmed through a pathology report or a clinical course consistent with the disease, as determined by a local pathologist, if a pathology specimen is unavailable.
• ECOG performance status: 0 or 1 (fully active or restricted in strenuous activity but ambulatory).
• Life expectancy: \>5 years.
• Germline testing: Must have germline testing completed at the time of initial diagnosis and, if applicable, at recurrence.
• No evidence of distant metastasis: No evidence of soft tissue disease metastasis (visceral or lymph nodes) on CT/MRI scan.
• No active or organ-threatening autoimmune disease: Participants must not have an active or organ-threatening autoimmune disease.
• High-risk or very high-risk prostate cancer: Based on 2024 NCCN guidelines: PSA \>20 ng/mL or Gleason Grade Group ≥4 or ≥cT3a.
• Adequate hematologic and organ function: Defined by specific laboratory values (ANC, lymphocyte count, platelet count, hemoglobin, INR/aPTT, AST, ALT, alkaline phosphatase) obtained within 14 days prior to baseline, with specific exceptions stated in the protocol for participants with liver or bone metastases or those with known Gilbert disease.
• Ability to attend study visits and return for adequate follow-up.
• Agreement to practice effective contraception: Non-sterile males must agree to use effective contraception (condom, vasectomy, or other barrier methods) for up to 7 months after treatment.

You may not qualify if:

• Prior treatment for prostate cancer: Participants who have undergone any prior surgical, cryotherapy, or high-intensity focused ultrasound treatment for prostate cancer are excluded.
• Organ transplantation: Receipt of any organ transplantation (excluding those not requiring immunosuppression, such as corneal or hair transplants) excludes participants from the study.
• Chronic systemic corticosteroid use: Chronic administration (\>14 days) of systemic corticosteroids within 28 days of study treatment initiation excludes participants. However, minimal systemic absorption (inhaled steroids, nasal sprays, topical agents) is permitted.
• Active autoimmune disease: Active autoimmune diseases (Addison's disease, Hashimoto's thyroiditis, systemic lupus erythematosus, Sjögren syndrome, scleroderma, myasthenia gravis, Goodpasture syndrome, or active Grave's disease) exclude participants. However, a history of autoimmunity that did not require systemic immunosuppression and did not threaten vital organ function is permitted.
• Use of medications affecting PSA: Use of medications known to alter PSA levels (5-alpha reductase inhibitors, phytoestrogens, saw palmetto) within 28 days before study treatment initiation excludes participants.
• Major surgery: Major surgery within 28 days of study treatment initiation excludes participants.
• Allergic reactions: A history of allergic reactions to compounds with similar chemical or biologic composition to the study drugs excludes participants.
• Clinically significant cardiovascular/cerebrovascular disease: This includes cerebral vascular accident/stroke, myocardial infarction, or unstable angina, congestive heart failure, or uncontrolled hypertension within specific timeframes before study enrollment.
• Serious intercurrent medical illness: Any serious intercurrent medical illness that could interfere with treatment participation.
• Active infections: Active HIV, hepatitis B (positive HBsAg), or hepatitis C infections exclude participation.
• Live attenuated vaccine administration: Administration of a live, attenuated vaccine within 3 weeks prior to study entry or anticipated during the study.
• Inability or unwillingness to comply: Participants assessed by the investigator as unable or unwilling to comply with the study requirements are excluded.

Sponsors & Collaborators

• ImmunityBio, Inc.: lead

MeSH Terms

Conditions

Prostatic Neoplasms

Interventions

ALT-803; Androgen Antagonists

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Intervention Hierarchy (Ancestors)

Hormone Antagonists; Hormones, Hormone Substitutes, and Hormone Antagonists; Physiological Effects of Drugs; Pharmacologic Actions; Chemical Actions and Uses

Study Officials

• Bruce Brown

  ImmunityBio, Inc.

  STUDY CHAIR

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: While the treatment involves multiple stages (pre-radiation immunotherapy, radiation, post-radiation immunotherapy), participants are assigned to one arm of the study and receive the complete treatment regimen within that arm. There's no crossover or other complex design element described; participants receive a consistent set of interventions according to their assigned group.

Study Record Dates

• First Submitted: December 20, 2024
• First Posted: January 9, 2025
• Study Start: December 1, 2025
• Primary Completion (Estimated): January 31, 2031
• Study Completion (Estimated): June 30, 2031
• Last Updated: May 5, 2026

Record last verified: 2026-04