Phase I Study of 203Pb-RMX-VH-PIB Dosimetry and Biodistribution in Patients With Solid Tumors Like GBM and PDAC

NCT07733674 | Recruiting Phase 1 FDA Drug

• 1 other identifier: RMX-VH-02
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this Phase I clinical trial is to evaluate how the imaging drug 203Pb- RMX-VH-PIB distributes in the body and how much radiation different organs receive in patients with glioblastoma multiforme (GBM) or pancreatic ductal adenocarcinoma (PDAC). The main questions it aims to answer are: How does 203Pb-RMX-VH-PIB spread in the body (biodistribution)? What is the radiation dose delivered to organs (dosimetry)? Participants will: Receive a single IV injection of 203Pb-RMX-VH-PIB. Undergo multiple SPECT/CT imaging scans. Have blood, urine, vital signs, and ECG monitored for safety. Be followed for any side effects for up to 30 days.

Conditions

Glioblastoma Multiforme (GBM); Pancreatic Ductal Adenocarcinoma (PDAC)

Keywords

Glioblastoma Multiforme (GBM); Pancreatic Ductal Adenocarcinoma (PDAC); 203Pb-RMX-VH-PIB; SPECT/CT Imaging; Brain Tumor; Radiopharmaceutical; Pancreatic Cancer; RMX-VH-02; lead-203; radiolabeled peptide; investigational radiopharmaceutical; diagnostic radiopharmaceutical; tumor-targeted radiopharmaceutical; malignant glioma; high-grade glioma; malignant brain tumor; astrocytoma; IDH-wildtype glioblastoma; brain tumor targeting; Astrocytoma grad IV

Outcome Measures

Primary Outcomes (2)

• Whole-body and organ-specific absorbed radiation dose for 203Pb-RMX-VH-PIB

  Whole-body and organ-specific absorbed radiation doses will be estimated using serial quantitative SPECT/CT imaging and available blood and urine radioactivity data following a single intravenous administration of 203Pb-RMX-VH-PIB. Absorbed radiation doses will be summarized per unit of administered activity, such as mGy/MBq.

  From injection to up to 144 hours post-injection, multi-time-point SPECT/CT, e.g., ~1-2 h, 4-6 h, 24 h, 48 h, 120 h, 144h (conditional).

• Organ-Specific Absorbed Dose of 203Pb-RMX-VH-PIB

  For each subject, VOIs are drawn over critical organs (e.g., kidneys, liver, spleen, red marrow, pancreas, brain, thyroid, salivary glands) and target lesions. Time-activity curves are fit and residence times derived; absorbed dose per injected activity is computed with a standard MIRD schema (e.g., OLINDA/EXM or equivalent)

  From injection to up to 72 hours post-injection (multi-time-point SPECT/CT, e.g., ~1-2 h, 4-6h, 24 h, 48 h, 120h, 144h conditional)

Study Arms (1)

203Pb-RMX-VH-PIB Imaging

EXPERIMENTAL

All participants will receive a single intravenous injection of 203Pb-RMX-VH-PIB (5.0 ± 10% mCi). Following administration, participants will undergo multiple SPECT/CT scans to evaluate the biodistribution and radiation dosimetry of the investigational radiopharmaceutical. Safety assessments will include monitoring of vital signs, blood exams, and electrocardiograms (ECGs) before and after dosing, with adverse events recorded for up to 30 days.

Drug: 203Pb-RMX-VHPIB injection; Diagnostic Test: SPECT/CT Imaging

Interventions

203Pb-RMX-VHPIB injection DRUG

A single intravenous (IV) injection of the investigational radiopharmaceutical 203Pb-RMX-VHPIB administered to eligible patients.

203Pb-RMX-VH-PIB Imaging

SPECT/CT Imaging DIAGNOSTIC_TEST

Serial whole-body and region-specific SPECT/CT scans performed after IP administration to assess biodistribution and dosimetry

203Pb-RMX-VH-PIB Imaging

Eligibility Criteria

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

You may qualify if:

• Signed informed consent.
• Subjects aged ≥18 years.
• Karnofsky status ≥60.
• Negative urine pregnancy test in women of childbearing potential.
• Histologically confirmed and /or highly suspicious GBM (Adult type Astrocytoma grade IV both IDH-Mutant and IDH-Wild Type) including primary, recurrent or stable enhancing residual or primary, recurrent or stable enhancing residual PDAC.
• a. GBM group i. Contrast enhanced Brain MRI image with results compatible with GBM within the 2 weeks of dosing day.
• ii. Tumor size of ≥ 1.0 cm in any dimension by MRI. iii. No antiangiogenic therapy within 4 weeks of the day of dosing. iv. No chemotherapy within 2 weeks of the day of dosing. v. Subjects receiving corticosteroids must be on a stable or decreasing dose regimen prior to enrollment b. PDAC group i. No chemotherapy within 2 weeks of the day of dosing ii. Tumor size of ≥ 1.0 cm in any dimension by MRI or CT
• Recent blood test results (within 4 weeks pre-dose) as follows:
• WBC: ≥ 2 x 109/L
• Haemoglobin: ≥ 8 g/dL
• Platelets: ≥75 x 109/L
• ALT, AST, AP ≤ 5 times ULN
• Bilirubin: ≤ 2 times ULN
• Creatinine clearance ≥ 60 mL/min, calculated by the Cockcroft-Gault equation

You may not qualify if:

• Known hypersensitivity to RMX-VH peptide analogue, 203Pb-RMX-VH-PIB, 203Pb (Lead) , or any of the excipients of 203Pb-RMX-VH-PIB.
• Inability to undergo MRI or CT/SPECT/CT scans
• Current somatic or psychiatric disease/condition that may interfere with consent or the objectives and assessments of the study.
• Pregnancy or plans to conceive during the course of study participation.
• In GBM groups participants requiring MRI: History of hypersensitivity or contraindication to gadolinium-based contrast agents, including prior allergic or anaphylactoid reactions to gadolinium contrast media, or any condition (e.g., severe renal impairment, acute kidney injury) that, in the investigator's judgment, increases the risk associated with gadolinium administration.
• In PDAC groups participants requiring CT scans: Any contraindications to iodinated contrast agents include a history of severe hypersensitivity or allergic reaction to iodinated contrast media, significant renal impairment (e.g., eGFR \< 30 mL/min/1.73 m² or acute kidney injury), uncontrolled hyperthyroidism or other thyroid disorders that may worsen with iodine exposure, prior contrast-induced nephropathy, pregnancy, and any unstable medical condition such as severe heart failure or hemodynamic instability that, in the investigator's judgment, increases the risk of contrast administration.
• Male and female participants of childbearing potential who are unwilling or unable to use an acceptable method of contraception for the duration of the study.
• Women who are breastfeeding
• Participants who are currently receiving treatment with statins (HMG-CoA reductase inhibitors), including but not limited to atorvastatin, rosuvastatin, pitavastatin, simvastatin, lovastatin, pravastatin, or fluvastatin, are excluded unless the medication has been discontinued for at least four (4) drug half-lives prior to administration of the investigational product

Sponsors & Collaborators

• Radiomedix, Inc.: lead

Study Sites (1)

Excel Diagnostics & Nuclear Oncology Center

Houston, Texas, 77042, United States

RECRUITING

MeSH Terms

Conditions

Glioblastoma; Brain Neoplasms; Pancreatic Neoplasms; Glioma; Astrocytoma

Condition Hierarchy (Ancestors)

Neoplasms, Neuroepithelial; Neuroectodermal Tumors; Neoplasms, Germ Cell and Embryonal; Neoplasms by Histologic Type; Neoplasms; Neoplasms, Glandular and Epithelial; Neoplasms, Nerve Tissue; Central Nervous System Neoplasms; Nervous System Neoplasms; Neoplasms by Site; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Digestive System Neoplasms; Endocrine Gland Neoplasms; Digestive System Diseases; Pancreatic Diseases; Endocrine System Diseases

Central Study Contacts

Ebrahim Delpassand, MD, FACNM

CONTACT

713-499-9733; edelpassand@radiomedix.com

Izabela Tworowska, MS Pharm Clinical, Ph.D

CONTACT

832-868-2812; itworowska@radiomedix.com

Study Design

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

Model Details: This is a single group, open-label study in which all participants with glioblastoma multiforme (GBM) or pancreatic ductal adenocarcinoma (PDAC) will receive a single intravenous dose of 203Pb-RMX-VH-PIB. Participants will then undergo multiple SPECT/CT scans to evaluate biodistribution and dosimetry. Sub-groups (GBM vs PDAC; biodistribution vs dosimetry) are used for analysis purposes only, but all participants receive the same intervention.

Study Record Dates

• First Submitted: July 24, 2026
• First Posted: July 29, 2026
• Study Start (Estimated): August 15, 2026
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): June 30, 2027
• Last Updated: July 29, 2026

Record last verified: 2026-07

Locations

US (1)