Safety and Targeting of Anti-hk2 Antibody in mCRPC

SpectronRX

Status and phase: Terminated; Early Phase 1

Conditions: Metastatic Disease; Castration-Resistant Prostatic Cancer

Treatments: Drug: 111In-DOTA-h11B6

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT04116164

GID5490

Details and patient eligibility

About

This is an imaging trial, to develop h11B6 as a therapeutic radiopharmaceutical for men with mCRPC.

This imaging study will be conducted to confirm the safety and estimate the mass amount of antibody h11B6, and confirm in vivo tumor targeting of the antibody, using Indium-111 (111In) radiolabeled h11B6 in subjects with advanced prostate cancer. This study will also provide the dosimetric information crucial for Phase 1 therapy.

Full description

It is the intent to develop h11B6 as a therapeutic radiopharmaceutical for men with mCRPC. This Phase 0 study will be conducted to confirm the safety, estimate the mass amount, and confirm in vivo tumor targeting of the antibody. This study will use Indium-111 (111In) radiolabeled h11B6 in subjects with mCRPC to image known sites of disease and identify a favorable mass amount of antibody for satisfactory tumor targeting with minimal/no accumulation off-target. In cohort 1, In-111 labeled h11B6 will remain fixed at 2 mg, and additional h11B6 will be added in 2 sub-cohorts (8 mg and 18 mg respectively); up to 6 patients may be entered into a sub-cohort. Additional patients (up to 6) will be studied once the most favorable mass and imaging time point have been established, to establish targeting of antibody to known disease.

This study will provide the dosimetric information crucial for Phase 1 therapy.

Enrollment: 27 patients

Sex: Male

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Subjects with mCRPC will be eligible if they meet the following criteria:
• Eastern Cooperative Oncology Group (ECOG) ≤ 1
• Histologically or cytologically confirmed adenocarcinoma of the prostate
• Castrate levels of testosterone (<50 ng/dL [1.74 nmol/L])
• Metastatic disease documented by imaging
• Documented progressive mCRPC with androgen involvement as defined by - Prostate Cancer Working Group 3
• Acceptable laboratory parameters
• At least 28 days since administration of any therapeutic radioactive isotope
• Able to tolerate the conditions required to perform imaging studies (e.g., lying flat for at least 1 hour).

Exclusion criteria

• Known hypersensitivity to proteins, or other allergic diathesis that, in the opinion of the investigator, makes an immune response to humanized antibody likely
• Radiotherapy or immunotherapy within 30 days, or single fraction of palliative radiotherapy within 14 days of administration of study agent
• Any condition that, in the opinion of the Investigator, would impair the subject's ability to comply with study procedures and required study visits
• Active, symptomatic, or untreated brain metastases.

Trial design

Primary purpose: Other

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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27 participants in 1 patient group

Dosimetry and targeting

Experimental group

Description:

Three sub-cohorts in cohort 1 will receive one slow bolus IV injection of 2 mg 111In-DOTA-h11B6 with 0, 8 and 18 mg unlabeled h11B6 respectively. In cohort 2, up to 6 patients will receive a slow bolus IV injection of 2 mg 111In-DOTA_h11B6 with any unlabeled h11B6 as determined from cohort 1, and will be imaged at one time-point

Treatment:

Drug: 111In-DOTA-h11B6