Outcomes of men with high-risk biochemically recurrent prostate cancer who suspended enzalutamide monotherapy treatment in the phase 3 EMBARK study.
Bibliographic record
Abstract
15 Background: In the 3-arm EMBARK trial, enzalutamide (enza) + leuprolide acetate (leuprolide) and enza monotherapy (mono) showed statistically superior and clinically meaningful improvements in metastasis-free survival (MFS) vs placebo + leuprolide (alone) in patients (pts) with high-risk biochemically recurrent (BCR) prostate cancer. Based on serum prostate-specific antigen (PSA) response, treatment (tx) was suspended at week 37 in 304 (85.9%) pts in the enza mono arm and 240 (67.8%) in the leuprolide-alone arm; pts who did not meet suspension criteria continued tx. Outcomes with enza mono vs leuprolide alone by tx suspension status are presented. Methods: EMBARK is a double-blind phase 3 study of pts with high-risk BCR (i.e., PSA doubling time (PSADT) ≤9 months and PSA ≥2 ng/mL above nadir post-radiotherapy [RT] or ≥1 ng/mL after radical prostatectomy [RP] ± postoperative RT). Pts were randomized (1:1) to enza mono (160 mg/day, open-label) or leuprolide alone (22.5 mg every 12 weeks). PSA <0.2 ng/mL at week 36 triggered tx suspension at week 37; tx restarted when PSA reached ≥2 ng/mL or ≥5 ng/mL for pts with or without primary RP, respectively. The proportion of pts with undetectable PSA 2 years after tx suspension was a secondary endpoint. MFS (by blinded independent central review) was analyzed descriptively in each tx arm by suspension status. P-values were nominal. Results: In the suspension group, the 3-year MFS rate (95% CI) was 88.1% (83.8–91.4%) for enza mono and 90.0% (85.3–93.2%) for leuprolide alone; there was no difference in MFS (hazard ratio [HR] 0.840, 95% CI 0.575–1.226; P=0.3659). In the no suspension group, 3-year MFS rates were 88.5% (68.5–96.2%) and 66.9% (55.4–76.1%), respectively; MFS was longer with enza mono vs leuprolide alone (HR 0.340, 95% CI 0.118–0.985; P=0.0378). In the suspension group vs the no suspension group, a greater proportion had received prior RP (enza mono: 78.9 vs 41.9%; leuprolide alone: 78.3 vs 52.2%) or RP and RT (enza mono: 50.7 vs 16.1%; leuprolide alone: 55.0 vs 38.0%), while baseline median PSADT was similar (enza mono: 4.9 vs 5.9 months; leuprolide alone: 5.0 vs 4.8 months). The proportion (95% CI) of pts with undetectable PSA 2 years after tx suspension was 4.6% (2.5–7.6%) for enza mono and 9.6% (6.2–14.0%) for leuprolide alone ( P=0.0326). Conclusions: In pts with high-risk BCR who suspended tx, the tx effect on MFS with enza mono was not different compared with leuprolide alone, though more pts reached tx suspension criteria with enza mono. However, in the no suspension group, enza mono prolonged MFS vs leuprolide alone, though the number of MFS events was limited (n=4). Pts with prior RP were also more likely to reach the PSA threshold for tx suspension. Few pts who suspended tx had undetectable PSA after 2 years, regardless of tx. Clinical trial information: NCT02319837 .
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.002 | 0.002 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.003 | 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".