December 14, 2016 — Cancer Targeted Technology (CTT), a privately-held Seattle-based biotechnology firm focusing on small molecules that target pivotal enzyme targets on cancer, announced a Phase I clinical trial has commenced in men with high-risk metastatic prostate cancer. In late August, the U.S. Food and Drug Administration cleared CTT’s first Investigational New Drug Application (IND) for a positron emission tomography (PET) imaging agent, CTT1057, labeled with a two-hour half life radiolabel, fluorine-18, and targeting prostate-specific membrane antigen (PSMA).
PSMA is over-expressed on prostate cancer and this expression increases as the cancer metastasizes and becomes castrate-resistant. CTT’s phosphoramidate-based agents bind irreversibly to PSMA and unlike other agents targeting PSMA, this distinctive mode of binding enhances uptake and internalization by tumor cells, leading to increased accumulation of the drug and radiolabel within the tumor. The first patient in this trial was imaged in early November and the study is supported by a $2M Small Business Innovation Research (SBIR) grant.
In the trial, CTT1057 will either be used alone or with CTT’s companion radiotherapeutic drug, CTT1403, that targets metastatic prostate cancer, according to CTT CEO and SBIR principal investigator Beatrice Langston-Webster. CTT1403 is currently undergoing IND-enabling studies.”
Automated radiolabeling of the drug and the clinical trials are being conducted at the University of California, San Francisco (UCSF). The principal investigator for the clinical trial is Rahul Aggarwal, M.D. The radiolabeling is directed by UCSF collaborator Henry VanBrocklin, Ph.D., director of the Radiopharmaceutical Research Program, who worked with CTT on the initial development of CTT1057, along with Cliff Berkman, Ph.D., professor of chemistry at Washington State University, who first discovered and synthesized the drug.
VanBrocklin commented, “We are excited to initiate the clinical phase of development of this new imaging agent and look forward to the results of these key studies.”
This CTT-sponsored Phase I trial is entitled “A Phase 1 Trial for Evaluation of the Safety, Pharmacokinetics, and [18F] Radiation Dosimetry of CTT1057, a Small Molecule Inhibitor of Prostate Specific Membrane Antigen (PSMA).” The primary objective of this trial is to evaluate the safety and tolerability of CTT1057. An additional endpoint includes the assessment of sensitivity and specificity of CTT1057 PET imaging on a lesion-by-lesion basis as compared with standard imaging in metastatic prostate cancer. Twenty patients will be enrolled in parallel in two cohorts: Cohort A will enroll patients with prostate cancer prior to radical prostatectomy (N = 5) and Cohort B will enroll patients with evidence of metastatic castration-resistant prostate cancer (N = 15). The study is currently enrolling and is expected to conclude in mid 2017.
For more information: www.cancertargetedtechnology.com
January 28, 2026 
