177Lu-BetaBart in Patients With Relapsed/Refractory, Locally Advanced Inoperable, or Metastatic Solid Tumors

NCT07189871 | Recruiting Phase 1 DMC FDA Drug

• 1 other identifier: BetaBart-US-101
• Study Type: interventional
• Target: 61
• Locations: 1 country
• Sites: 4

Brief Summary

A Phase 1/2a Dose Escalation and Expansion Study of the Safety, Tolerability, and Preliminary Clinical Activity of 177LuBetaBart, a 177Lu-Labeled Anti-B7-H3 Monoclonal Antibody, in Patients with Relapsed/Refractory, Locally Advanced Inoperable, or Metastatic Solid Tumors

Conditions

Castration-Resistant Prostate Cancer (CRPC); Colorectal Cancer; NSCLC (Non-small Cell Lung Cancer); Ovarian Cancer; Cervical Cancer; Endometrial Cancer; TNBC, Triple Negative Breast Cancer; Small Cell Lung Cancer (SCLC ); Head &Amp; Neck Squamous Cell Carcinoma (HNSCC); Esophageal Squamous Cell Carcinoma (ESCC)

Keywords

Castration-resistant prostate cancer (CRPC); colorectal cancer (CRC); non-small-cell lung cancer (NSCLC); small-cell lung cancer (SCLC); head and neck squamous cell carcinoma (HNSCC); ovarian cancer; cervical cancer; endometrial cancer; triple negative breast cancer (TNBC); esophageal squamous cell carcinoma (ESCC); B7-H3; 177Lu; radiotheranostics; radioligand therapy; radioimmunotherapy; monoclonal antibody; metastatic solid tumors

Outcome Measures

Primary Outcomes (4)

• Recommended dose(s) of 177Lu-BetaBart for future exploration (phase 1)

  Incidence of dose-limiting toxicities (DLTs) during the 6 weeks following the first 177Lu-BetaBart injection

  6 weeks

• Incidence of treatment emergent adverse events of 177-Lu-BetaBart (phase 1) (Safety and Tolerability)

  As defined per Common Terminology Criteria for Adverse Events (CTCAE) v5.0

  6 weeks

• To assess the preliminary anti-tumor activity of 177Lu-BetaBart at the RP2D (phase 2a)

  Objective response rates (ORR) as assessed by RECIST v1.1

  Up to 30 weeks

• To assess preliminary anti-tumor activity, as defined by biochemical response, in CRPC participants who are treated with 177Lu-BetaBart at the RP2D (phase 2a)

  Proportion of participants who achieve a best response of prostate-specific antigen (PSA)50

  Up to 30 weeks

Secondary Outcomes (9)

• To assess the preliminary anti-tumor activity of 177Lu-BetaBart (phase 1)

  Up to 30 weeks

• To assess preliminary anti-tumor activity, as defined by biochemical response, in castration-resistant prostate cancer (CRPC) participants treated with 177Lu-BetaBart (phase 1)

  Up to 30 weeks

• Incidence of treatment emergent adverse events of 177-Lu-BetaBart at the RP2D (phase 2a) (Safety & Tolerability)

  6 weeks

• Pharmacokinetics of 177Lu-BetaBart (phase 1)

  72 Hours

• Radiation dosimetry of 177Lu-BetaBart (phase 1)

  72 hours

Study Arms (1)

177 Lu-BetaBart - Dose escalation and Phase 2a expansion

EXPERIMENTAL

Dose escalation and treatment and imaging period

Drug: 177Lu-BetaBart

Interventions

177Lu-BetaBart DRUG

BetaBart administered by intravenous (IV) infusion every 6 weeks

Also known as: RV-01, B335 177Lu-DOTA-anti-B7-H3

177 Lu-BetaBart - Dose escalation and Phase 2a expansion

Eligibility Criteria

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

You may qualify if:

• Willing and able to provide informed consent prior to start of any study procedures and assessments and must be willing to comply with all study procedures.
• Participants ≥ 18 years of age.

You may not qualify if:

• a. \*Progressive CRPC defined as castrate levels of testosterone and progressing by at least one of the following criteria: i. Serum PSA progression consisting of two consecutive increases in PSA measured at least 1 week apart. The minimal baseline value is 2.0 ng/mL.
• ii. Soft tissue progression defined as a ≥20% increase in the sum of the diameter (short axis for nodal lesions and long axis for non-nodal lesions) of all target lesions based on the smallest sum of the diameter since the previous treatment was started or the appearance of one or more new lesions by computed tomography (CT)/magnetic resonance imaging (MRI).
• iii. Progression of bone disease defined by Prostate Cancer Working Group 3 (PCWG3) as evaluable disease or new bone lesions by bone scan.
• iv. Identification of new soft tissue or bone lesions on prostate-specific membrane antigen (PSMA) positron emission tomography (PET) imaging.
• b. \*Metastatic disease defined as either or both of the following: i. Documented M1 disease on conventional imaging (CT/MRI of the chest/abdomen/pelvis and/or Technetium 99m \[99mTc\] whole-body bone scan) ii. Identification of bone lesion(s), extra-pelvic soft tissue lesion(s), or visceral metastases on PSMA PET imaging with an FDA-approved imaging agent (e.g., 68Ga-PSMA-11, 18F-DCFPyL, or 18F-rhPSMA-7.3) c. \*Progression following treatment with ADT and at least one ARSI (e.g., enzalutamide, apalutamide, darolutamide, and/or abiraterone acetate). If a participant is currently on ADT, they should continue ADT for the duration of their participation in the study but will not be permitted to start a new therapy or ADT regimen. If a participant has progressed on an ARSI, they will have the option to remain on the same ARSI or discontinue therapy. If they discontinue the ARSI, a 28-day washout period will be required prior to initiating study intervention.
• d. Prior definitive and palliative external beam radiation therapy and stereotactic body radiation therapy is allowed.
• Note: Participants with extended external beam radiation therapy to the axial skeleton, which in the opinion of the Investigator may pose a risk for increased myelotoxicity, will be discussed with the Sponsor to determine eligibility.
• e. Participants with liver metastases are eligible if they meet the following criteria: i. ≤3 lesions i. All lesions must be ≤2 cm in the short axis ii. SUVmean ≥2 x that of liver parenchyma f. \*Prior treatment with one taxane-based chemotherapy is allowed but not required. A taxane-based chemotherapy is defined as a minimum exposure of two cycles of a taxane chemotherapy.
• Participants must have documented disease progression during or after their most recent line of anticancer therapy. Participants must be refractory to or intolerant of standard of care therapy or have no standard of care therapy available that is likely to provide clinical benefit. Any number of prior treatment lines are allowed.
• Must have at least 1 measurable target lesion according to RECIST v1.1. (Note: this does not apply for CRPC)
• Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2
• Participants must have a life expectancy of ≥ 4 months in the opinion of the Investigator.
• Participants of child-bearing potential (CBP) must have a negative β-hCG test and must not be breastfeeding. Participants of CBP are defined as those who are not surgically sterile or post-menopausal. Participants will be considered post-menopausal if they have been amenorrheic for 12 months without an alternative medical cause. Participants \< 50 years of age who meet the criteria for post-menopausal status without previous surgical sterilization should be considered for further investigation with luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels to confirm serological post-menopausal status.
• Participants of CBP must agree to use a highly effective method of contraception during the study and for 6 months after the last dose of 177Lu-BetaBart, as described in Appendix 4.
• Male participants who are able to father a child must agree to avoid impregnating a partner and to adhere to a highly effective method of contraception during the study and for 6 months after the last dose of 177Lu-BetaBart, as described in Appendix 4. All male participants must agree to not donate sperm during the study and for 6 months after the last dose of 177Lu-BetaBart.

Sponsors & Collaborators

• Radiopharm Theranostics, Ltd: lead
• Medpace, Inc.: collaborator

Study Sites (4)

Dothan Hematology & Oncology

Dothan, Alabama, 36303, United States

RECRUITING

BAMF Health

Grand Rapids, Michigan, 49503, United States

RECRUITING

Nebraska Cancer Specialists

Omaha, Nebraska, 68130, United States

RECRUITING

XCancer

Omaha, Nebraska, 68130, United States

RECRUITING

MeSH Terms

Conditions

Colorectal Neoplasms; Carcinoma, Non-Small-Cell Lung; Ovarian Neoplasms; Uterine Cervical Neoplasms; Endometrial Neoplasms; Triple Negative Breast Neoplasms; Small Cell Lung Carcinoma; Esophageal Squamous Cell Carcinoma; Squamous Cell Carcinoma of Head and Neck

Condition Hierarchy (Ancestors)

Intestinal Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Colonic Diseases; Intestinal Diseases; Rectal Diseases; Carcinoma, Bronchogenic; Bronchial Neoplasms; Lung Neoplasms; Respiratory Tract Neoplasms; Thoracic Neoplasms; Lung Diseases; Respiratory Tract Diseases; Endocrine Gland Neoplasms; Ovarian Diseases; Adnexal Diseases; Genital Diseases, Female; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Genital Neoplasms, Female; Urogenital Neoplasms; Genital Diseases; Endocrine System Diseases; Gonadal Disorders; Uterine Neoplasms; Uterine Cervical Diseases; Uterine Diseases; Breast Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases; Carcinoma, Squamous Cell; Carcinoma; Neoplasms, Glandular and Epithelial; Neoplasms by Histologic Type; Neoplasms, Squamous Cell; Esophageal Neoplasms; Head and Neck Neoplasms; Esophageal Diseases

Central Study Contacts

Dimitris Voliotis, MD

CONTACT

646-535-5017; dv@radiopharmtheranostics.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: BOIN dose escalation during Phase 1 followed by dose expansion at RP2D during Phase 2a

Study Record Dates

• First Submitted: September 11, 2025
• First Posted: September 24, 2025
• Study Start: February 23, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2027
• Last Updated: March 27, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (4)