Pembrolizumab Plus Docetaxel Versus Docetaxel for Previously Treated Metastatic Castration-Resistant Prostate Cancer: The Randomized, Double-Blind, Phase III KEYNOTE-921 Trial
Bibliographic record
Abstract
PURPOSE The standard of care for metastatic castration-resistant prostate cancer (mCRPC) after second-generation androgen receptor pathway inhibitor (ARPI) therapy is still docetaxel. The randomized, double-blind, phase III KEYNOTE-921 trial (Clinicaltrials.gov identifier: NCT03834506 ) evaluated the efficacy and safety of pembrolizumab or placebo plus docetaxel for previously treated mCRPC. METHODS Adults with mCRPC who progressed after androgen-deprivation therapy and one ARPI were randomly assigned 1:1 to pembrolizumab or placebo plus docetaxel with concomitant prednisone. Dual primary end points were radiographic progression-free survival (rPFS) by blinded independent central review per Prostate Cancer Working Group 3–modified RECIST 1.1 and overall survival (OS). Safety was a secondary end point. RESULTS Between May 30, 2019, and June 17, 2021, 515 participants were randomly assigned to pembrolizumab plus docetaxel and 515 to placebo plus docetaxel. Median time from random assignment to data cutoff date (June 20, 2022) at final analysis (FA) was 22.7 months (range, 12.1-36.7). At first interim analysis (data cutoff date: September 27, 2021), median rPFS was 8.6 months (95% CI, 8.3 to 10.2) with pembrolizumab plus docetaxel versus 8.3 months (95% CI, 8.2 to 8.5) with placebo plus docetaxel (hazard ratio [HR], 0.85 [95% CI, 0.71 to 1.01]; P = .03). At FA, median OS was 19.6 months (95% CI, 18.2 to 20.9) versus 19.0 months (95% CI, 17.9 to 20.9), respectively (HR, 0.92 [95% CI, 0.78 to 1.09]; P = .17). Grade ≥3 treatment-related adverse events occurred in 43.2% of participants who received pembrolizumab plus docetaxel and 36.6% of participants who received placebo plus docetaxel. Two and seven participants, respectively, died due to a treatment-related adverse event. Pneumonitis was the most common immune-mediated adverse event (7.0% v 3.1%). CONCLUSION The addition of pembrolizumab to docetaxel did not significantly improve efficacy outcomes for participants with previously treated mCRPC. The current standard of care remains unchanged.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.002 |
| Meta-epidemiology (narrow) | 0.002 | 0.001 |
| Meta-epidemiology (broad) | 0.002 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.002 | 0.003 |
| Insufficient payload (model declined to judge) | 0.007 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".