The FDA has approved gallium 68 PSMA-11 (Ga 68 PSMA-11) for positron emission tomography (PET) imaging of prostate-specific membrane antigen (PSMA)-positive lesions in men with prostate cancer (PCa).
The radioactive diagnostic agent is indicated for patients with suspected PCa recurrence or metastasis and is administered by intravenous injection.
“Ga 68 PSMA-11 is an important tool that can aid health care providers in assessing prostate cancer,” Alex Gorovets, MD, acting deputy director of the Office of Specialty Medicine in FDA’s Center for Drug Evaluation and Research stated in a press release from the agency. “With this first approval of a PSMA-targeted PET imaging drug for men with prostate cancer, providers now have a new imaging approach to detect whether or not the cancer has spread to other parts of the body.”
The FDA’s approval is based on data from 2 recent trials. In the first trial, 325 patients with higher-risk PCa underwent PET/computed tomography (CT) or PET/magnetic resonance imaging (MRI) scans performed with Ga 68 PSMA-11 prior to radical prostatectomy and lymph node dissection. Surgery patients with positive readings in the pelvic lymph nodes on Ga 68 PSMA-11 PET had a “clinically important” rate of metastases confirmed by surgical pathology. Obtaining this information from Ga 68 PSMA-11 PET imaging may spare certain patients from undergoing unnecessary surgery, according to the FDA.
In the second trial, 635 men with biochemical recurrence received a single Ga 68 PSMA-11 PET/CT scan or PET/MR scan. Three-quarters of these patients showed at least 1 positive lesion on Ga 68 PSMA-11 PET in the bone, prostate bed, pelvic lymph node, or extra-pelvic soft tissue. Biopsy pathology, conventional imaging, serial PSA levels generally corroborated recurrence or metastasis in an estimated 91% of cases.
Ga 68 PSMA-11 binding may occur in other types of cancer as well as non-malignant processes that may lead to misdiagnosis, the FDA pointed out. Ga 68 PSMA-11 also contributes to cumulative radiation exposure. The most common adverse events with Ga 68 PSMA-11 were nausea, diarrhea, and dizziness.
FDA approves first PSMA-targeted PET imaging drug for men with prostate cancer [news release]. FDA; December 1, 2020.