The UCLA and UCSF scan study behind the first US approval of gallium PSMA PET: in men heading for prostate surgery it was very reliable when it called a pelvic lymph node positive, but it still missed about three in five of the nodes that pathology later found.
PSMA-PreRP is the US Illuccix label's name (Study 1) for the investigator-initiated, prospective, multicentre, single-arm, open-label phase 3 diagnostic-efficacy programme of 68Ga-PSMA-11 PET before planned radical prostatectomy at the University of California, San Francisco and the University of California, Los Angeles (Hope and colleagues, JAMA Oncology 2021; ClinicalTrials.gov NCT03368547, NCT02611882 and NCT02919111). From December 2015 to December 2019, men with intermediate- to high-risk prostate cancer had one PET scan with 3 to 7 mCi of 68Ga-PSMA-11. Each scan was read centrally by three blinded readers with a majority rule, and pelvic nodal findings were compared with histopathology after prostatectomy and pelvic lymph node dissection using nodal-region correlation.
Of 764 men imaged, 277 (36 percent) went on to prostatectomy with lymph node dissection and formed the efficacy cohort; 75 of them (27 percent) had pelvic nodal metastasis on pathology. PET was positive for pelvic nodal, extrapelvic nodal and bone disease in 14, 1 and 3 percent. Per-patient sensitivity for pelvic nodal metastasis was 0.40 (95 percent CI 0.34 to 0.46), specificity 0.95 (0.92 to 0.97), positive predictive value 0.75 (0.70 to 0.80) and negative predictive value 0.81 (0.76 to 0.85). Of the 487 men who did not have surgery, most had radiotherapy (69 percent of those with follow-up) or systemic therapy (22 percent).
The authors state that the collaboration formed the foundation of the New Drug Application for 68Ga-PSMA-11, approved in December 2020. Telix's Illuccix kit (FDA December 2021) cites the programme as Study 1 (NCT03368547 and NCT02919111) and states that its efficacy for initial staging rests on that study of another gozetotide formulation; the label's own summary reports a 325-patient two-centre cut with 123 evaluable, which is a different analysis set from the paper's and is not used for the outcome rows here.
Numbers are from the trial as recorded here; see the source links in the table below. This is orientation, not medical advice: ask your team how closely the trial population matches you.
764 registered.
Reported as 0.40; 95% CI 0.34 to 0.46; 75 of 277 men had nodal metastasis on pathology
SourceReported as 0.95; 95% CI 0.92 to 0.97
SourceReported as 0.75; 95% CI 0.70 to 0.80
SourceReported as 0.81; 95% CI 0.76 to 0.85
Source| Endpoint | Arm | n | Value | HR (95% CI) | p | Source |
|---|---|---|---|---|---|---|
| Sensitivity for pelvic nodal metastasis (per patient, nodal-region correlation, versus histopathology)primary | 68Ga-PSMA-11 PET | 277 | 40% | - | - | link |
| Specificity for pelvic nodal metastasis (per patient, nodal-region correlation, versus histopathology)primary | 68Ga-PSMA-11 PET | 277 | 95% | - | - | link |
| Positive predictive value for pelvic nodal metastasis | 68Ga-PSMA-11 PET | 277 | 75% | - | - | link |
| Negative predictive value for pelvic nodal metastasis | 68Ga-PSMA-11 PET | 277 | 81% | - | - | link |
Shares Gallium-68 gozetotide (PSMA-11), Illuccix (kit for Ga-68 gozetotide), PSMA, PSMA PET.
Shares UCLA Jonsson Comprehensive Cancer Center, PSMA, PSMA PET, Prostate cancer.
Shares UCLA Jonsson Comprehensive Cancer Center, PSMA, PSMA PET, Prostate cancer.
Shares Gallium-68 gozetotide (PSMA-11), PSMA PET, Prostate cancer.
Shares PSMA, Localised prostate cancer, high and very high risk, PSMA PET, PET/CT.
Shares UCSF Helen Diller Family Comprehensive Cancer Center, PSMA, PSMA PET, Prostate cancer.
Shares PSMA, PSMA PET, PET/CT, Prostate cancer.
Shares PSMA, PSMA PET, Prostate cancer.