Reviews/Targeted Therapy Prostate Cancer/Lu-PSMA-617 overall survival in metastatic castration-resistant prostate cancer (VISION)
Psma · PC-PSMA-01 · v2
Borderline: within 4 points of the Established/Likely boundary, so a re-grade could land either side.
A large international trial [1] tested this radioactive drug added to standard care against standard care alone in men with advanced prostate cancer whose disease carried the PSMA target and who had already been treated with a hormone-pathway drug and chemotherapy. On both measures the claim names — how long people lived and how long before their scans showed the cancer growing — the drug arm did significantly better [1]. A very large real-world French program [18] saw a similar time-to-scan-progression, and an early small series [12] saw longer survival than an untreated comparison group. The main cautions the panel noted are that the trial was open-label, that the control arm was deliberately stripped of other active treatments, and that a separate trial reported in [17] found no survival difference against an active chemotherapy. These are reasons to read the survival benefit as being against that specific restricted comparator, not as proof over every alternative.
The pivotal phase 3 trial [1] reports significantly longer imaging-based progression-free survival (median 8.7 vs. 3.4 months; HR 0.40; P<0.001) and overall survival (median 15.3 vs. 11.3 months; HR 0.62; P<0.001) in the exact population the claim names. The large prospective real-world cohort [18] records a closely matching imaging PFS of 7.6 months versus 8.7 months in VISION. An early retrospective series [12] reports median survival of 29.4 weeks versus 19.7 weeks for a historical best-supportive-care group (HR 0.44; P=0.031). Supporting retrospective work [2] shows a PFS benefit when the agent is combined with an AR-pathway inhibitor (11 vs. 5.6 months; HR 0.47; p<0.01). Direction and significance of both named endpoints are consistent across the corpus. The contested point: The division is over how far the survival benefit generalises: [1] shows it against a comparator that explicitly excluded chemotherapy, immunotherapy and radium-223, while [17] reports the TheraP trial found no statistically significant OS difference against active cabazitaxel (16.4 vs. 19.4 months). The within-trial significance in [1] is not in question; what the OS benefit is benchmarked against is.
All 18 papers behind this claim with their DOIs and what each does to it, the panel’s arbitration, the evidence gap map and the open research questions. Free, and sent to your inbox.
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One reviewer's only job is to attack the finding. The challenges below were weighed before the grade was set.
VISION [1] was open-label, which raises risk of bias in the investigator-assessed radiographic PFS endpoint; overall survival is more robust to this.
The claim is carried essentially by one pivotal RCT [1]; the corroborating corpus ([12], [18], [2]) is retrospective or single-arm real-world data of lower evidential quality.
Where it remains uncertain. The benefit is measured against a comparator that excluded other active therapies [1]; against active cabazitaxel, [17] reports no significant OS difference (16.4 vs. 19.4 months).
Aleatory
The independent OS signal rests on [12], a 28-patient retrospective series whose weeks-based estimate carries wide sampling variability (HR 0.44; 95% CI 0.20-0.95).
Epistemic
One trial [1] carries both named endpoints; the rest of the corpus ([2], [3], [4], [12], [18]) is retrospective or single-arm, so independent randomised replication is absent.
Inferential
The imaging-based PFS endpoint in [1] was assessed in an open-label trial, so knowledge of assignment could influence the progression determination.
The load-bearing papers from a corpus of 18, each classified by what it does to the claim. Every DOI is taken from the corpus the claim was graded on.
Directly establishes both endpoints of the claim (rPFS and OS) as statistically significant in the VISION RCT.
“patients who had metastatic castration-resistant prostate cancer previously treated with at least one androgen-receptor-pathway inhibitor and one or two taxane regimens and who had PSMA-positive gallium-68 (68Ga)-labeled PSMA-11 positron-emission tomographic-computed tomographic scans”
Panel auditInternal validity: high · scope of inference: PSMA-positive mCRPC patients previously treated with at least one AR-pathway inhibitor and one or two taxane regimens.Key limitations: open-label design · standard care in control arm excluded chemotherapy, radium-223 and other active agents
Independent retrospective OS signal favouring Lu-PSMA versus a historical control arm.
“The estimated median survival was 29.4 weeks, significantly longer than survival in the historical best supportive care group (19.7 weeks [hazard ratio, 0.44; 95% confidence interval, 0.20-0.95]; P = 0.031).”
Panel auditInternal validity: low · scope of inference: mCRPC patients with exhausted conventional options treated with Lu-PSMA-617, compared to an earlier BSC cohort.Key limitations: historical control not randomized · small sample · retrospective · survival reported in weeks
Independent large real-world cohort corroborating the radiographic PFS magnitude seen in VISION.
“Median imaging PFS was 7.6 mo versus 8.7 mo in VISION.”
Panel auditInternal validity: medium · scope of inference: Real-world mCRPC patients progressing after ≥1 AR-pathway inhibitor and taxane, treated with 177Lu-PSMA-617 in France.Key limitations: single-arm descriptive · no concurrent comparator · population differs from VISION (older, more pretreated)
The comparison is combination versus monotherapy, with no untreated or standard-care arm, so it does not report whether the drug improves survival over standard care.
Panel auditInternal validity: low · scope of inference: mCRPC patients receiving Lu-177 PSMA-617 RLT at one institution, comparing addition of ARPI.Key limitations: retrospective · no standard-care arm · small combination subgroup
4 of 18 papers shown. The full review lists all of them, with the panel’s arbitration →
Claims are graded at each quarterly release, and re-graded between releases only when a pivotal trial lands. Every change is a new version of the claim.
A pivotal, well-powered RCT reports exactly the claimed significant OS and rPFS benefits in the named population, with independent corroboration and only design-level caveats.
Release 2026-q4 re-graded every claim from its corpus under protocol v0.19. An earlier release's grade is shown for the record; it came from an earlier protocol and is not a movement.
Assumptions that carry weight but are not themselves established.
The panel records the gap that would most move the claim, and the study that would close it.
Randomised comparison against an active alternative. The survival benefit in [1] is against a restricted control; [17] indicates no OS difference versus cabazitaxel, leaving superiority over active therapy open. The panel rates this the highest-importance open gap for the claim, and names the study design that would close it: A head-to-head randomised trial versus an active comparator such as cabazitaxel with overall survival as the primary endpoint.
Open question: Does 177Lu-PSMA-617 improve overall survival relative to an active comparator rather than restricted standard care? Why it is still open: [1] used a control excluding other active therapies and [17] reports no significant OS difference against cabazitaxel (16.4 vs. 19.4 months).
Priors is a sceptical first reader, not peer review, and not medical advice.
Release 2026-q4 · graded 26 Oct 2026 · protocol v0.19