Recruiting
Early Phase 1

HP 13C Bicarbonate

Sponsor:

Robert Flavell, MD, PhD

Code:

NCT05851365

Conditions

Prostate Cancer

Localized Prostate Carcinoma

Eligibility Criteria

Sex: Male

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Hyperpolarized Bicarbonate (13C)

Magnetic Resonance imaging

Study Details

Brief summary:

This is a single site, prospective pilot study to determine the feasibility and safety of the administration of HP 13C bicarbonate in 10 patients with prostate cancer to determine potential hydrogen (pH) values in surrounding tissue. The proposed study will evaluate pre-surgical participants with histologically confirmed localized prostate cancer who receive infusion of hyperpolarized 13C injection prior to MR imaging with endorectal coil.

Conditions

Prostate Cancer

Localized Prostate Carcinoma

Study ID

NCT05851365

Start date

Jul 6, 2023

Status verified date

Oct, 2026

Completion date

Dec 31, 2027

Anticipated

Primary completion date

Dec 31, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: Male

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

1. Patients age >=18 years.
2. Patients must have biopsy-proven adenocarcinoma of the prostate; biopsy may be performed outside of University of California, San Francisco (UCSF) if detailed results of sextant biopsy are available.
3. Tumor size of at least 1.0 cm in long axis on Magnetic resonance imaging (MRI) or ultrasound; if no prior imaging is available, at least 3 cores positive on biopsy.
4. Patients must have planned radical prostatectomy at UCSF within 12 weeks following protocol MRI/ magnetic resonance spectroscopy imaging) (MRSI).
5. Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1.
6. Demonstrates adequate organ function as defined below:

1. Adequate bone marrow function:

  • Absolute neutrophil count >=1,500 cells/µL.
  • Platelets >=75,000 cells/µL.
  • Hemoglobin >=9.0 gm/dL.
2. Adequate hepatic function:

  • Total bilirubin <1.5x upper limits of normal (ULN) (within normal institutional limits, unless elevated due to Gilbert's syndrome and direct bilirubin is within normal limits).
  • Aspartate aminotransferase (AST)/serum glutamic-oxaloacetic transaminase (SGOT) <=1.5 X institutional upper limit of normal.
  • Alanine aminotransferase (ALT)/serum glutamic-pyruvic transaminase (SGPT) <=1.5 X institutional upper limit of normal.
3. Adequate renal function:

  • Creatinine clearance >= 50 calculated using the Cockcroft-Gault equation, unless data exists supporting safe use at lower kidney function values, no lower than 30 mL/min/1.73 m\^2.
7. Ability to understand and the willingness to sign a written informed consent document.

Exclusion Criteria:

1. Patients who because of general medical or psychiatric condition, or physiologic status, cannot give valid informed consent.
2. Patients unwilling or unable to undergo MR imaging, including patients with contraindications to Magnetic resonance imaging (MRI) as per UCSF radiology departmental guidelines.
3. Patients who cannot tolerate or have contra-indications to endorectal coil insertion, for example, patients with a prior abdominoperineal resection of the rectum or latex allergy.
4. Patients with contra-indications to injection of gadolinium contrast as per UCSF radiology departmental guidelines.
5. Patients who take carbonic anhydrase inhibitors (e.g. acetazolamide, dichlorphenamide, methazolamide).
6. Metallic hip implant or any other metallic implant or device that distorts local magnetic field and compromises the quality of MR imaging.
7. Cryosurgery, surgery for prostate cancer, prostatic or pelvic radiotherapy prior to study enrollment. No limit on number of prior prostate biopsies. Prior Transurethral Resection of the Prostate (TURP) is not allowed.
8. Poorly controlled hypertension, with blood pressure at study entry >160/100. The addition of anti-hypertensives to control blood pressure is allowed for eligibility determination.
9. Congestive heart failure or New York Heart Association (NYHA) status >= 2. A history of clinically significant electrocardiogram (EKG) abnormalities, including QT prolongation, a family history of prolonged QT interval syndrome, or myocardial infarction (MI) within 6 months of study entry. Patients with rate-controlled atrial fibrillation/flutter will be allowed on study.

Study Design

Enrollment

10 participants

Anticipated

Intervention Model

Single group

Primary purpose

Diagnostic

Interventions and Outcome Measures

Arms

experimental: Pre-surgical participants with prostate cancer

The hyperpolarized 13C bicarbonate injection includes the administration of 35 mL injected intravenously (IV) at a rate of 5 mL/second followed by a 20 mL saline flush at 5 mL/second, followed by magnetic resonance (MR) imaging. The intervention will include routine and safety assessments 5 to 9 days after the injection.

Interventions

Hyperpolarized Bicarbonate (13C)

Given IV

Magnetic Resonance imaging

Magnetic resonance imaging is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body

Primary outcome measure

  • Proportion of participants with a signal to noise ratio > 2 [ Time Frame: Day of MR imaging (1 day) ]

Central Contacts and Locations

Central contacts

Locations

University of California, San Francisco

Recruiting

San Francisco, California, United States, 94143

Contacts

Principal Investigator:

Robert Flavell, MD, PhD

More Information

Sponsor

Robert Flavell, MD, PhD

Last update posted

Oct 13, 2026

Last verified

Oct, 2026

Keywords

  • Tissue pH
  • Magnetic Resonance (MR) Imaging

Trial information was received from ClinicalTrials.gov and was last updated on 2026-10-14. This information was provided to ClinicalTrials.gov by Robert Flavell, MD, PhD on 2026-10-13. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.