Curium has announced the completion of enrollment for the phase 3 SOLAR-RECUR trial (NCT06235099), which is designed to evaluate the diagnostic performance of copper Cu 64 prostate-specific membrane antigen (PSMA) I&T PET/CT in men with suspected biochemical recurrence of prostate cancer following radical prostatectomy or radiation therapy. The trial reached its target enrollment ahead of schedule, marking a significant milestone in Curium's theranostic program for prostate cancer.
The SOLAR-RECUR trial is a prospective, open-label study that enrolled 235 adult patients with histologically confirmed prostate adenocarcinoma who had undergone radical prostatectomy (more than 6 weeks prior to screening) or radiation therapy (more than 1 year prior to screening) with curative intent. Participants were required to have recurrent disease, indicated by a prostate-specific antigen (PSA) level greater than 0.2 ng/mL with subsequent confirmation after radical prostatectomy, or a PSA rise of 2 ng/mL over post-treatment nadir after radiation therapy. Each patient will receive 8 mCi (± 10%) of copper Cu 64 PSMA I&T via intravenous injection.
The primary outcome measures for the SOLAR-RECUR trial are the patient-level correct detection rate (CDR) and the region-level correct localization rate (CLR). Secondary outcome measures include CDR and CLR by PSA level and histopathology status, inter- and intra-reader agreement of PET/CT interpretation, and the incidence of adverse events (AEs). Final completion of the trial is anticipated for July 2025.
SOLAR-STAGE Trial
In parallel with SOLAR-RECUR, Curium is also conducting the SOLAR-STAGE trial, another phase 3 study evaluating copper Cu 64 PSMA I&T PET/CT. SOLAR-STAGE is focused on assessing the performance of this imaging technique in the staging of men with newly diagnosed unfavorable intermediate-risk, high-risk, or very-high-risk prostate cancer who are candidates for radical prostatectomy with pelvic lymph node dissection (PLND). This trial plans to enroll 323 adult patients and is actively enrolling patients across clinical trial sites in the US, with plans to expand to Europe.
To be eligible for the SOLAR-STAGE trial, patients must have histologically proven adenocarcinoma, be scheduled for prostatectomy with PLND, and have unfavorable intermediate- to very-high-risk disease according to National Comprehensive Cancer Network Guidelines. Similar to SOLAR-RECUR, patients will receive 8 mCi (± 10%) of copper Cu 64 PSMA I&T via intravenous injection.
The primary outcome measures for SOLAR-STAGE are sensitivity and specificity at 4 hours post-injection. Secondary outcome measures include inter- and intra-reader agreement of PET/CT interpretation and the incidence of adverse events (AEs). Additional outcome measures include the detection rate, sensitivity and specificity by risk group, and the impact of copper Cu 64 PSMA I&T PET/CT on clinical management. The final completion of SOLAR-STAGE is also expected in July 2025.
Sakir Mutevelic, MD, Curium’s Chief Medical Officer, stated that “Cu 64 PSMA I&T represents an important pillar in the development of our theranostic program for prostate cancer patients and the health care professionals treating them.”
