Table. Summary of Trial Outcomes.
| Characteristic | Men in the PREVAIL Trial | Men in the AFFIRM Trial | ||
|---|---|---|---|---|
| Responding to Enzalutamide With New Unconfirmed Bone Lesions (n = 177) | Responding to Enzalutamide Without New Unconfirmed Bone Lesions (n = 466) | Responding to Enzalutamide With New Unconfirmed Bone Lesions (n = 73) | Responding to Enzalutamide Without New Unconfirmed Bone Lesions (n = 331) | |
| Median rPFS (95% CI), mo | NR (12.3 to NR) | NR (14.1 to NR) | 13.6 (11.1 to 16.5) | 13.9 (13.6 to 16.5) |
| HR (95% CI) | 1.37 (0.81 to 2.30) | 1.21 (0.83 to 1.75) | ||
| P value | .23 | .32 | ||
| Median OS (95% CI), mo | NR (NR to NR) | 32.4 (31.5 to NR) | NR (16.5 to NR) | NR (NR to NR) |
| HR (95% CI) | 1.25 (0.85 to 1.83) | 1.94 (1.10 to 3.44) | ||
| Median time to PSA progression (95% CI), mo | 12.0 (11.1 to 13.9) | 13.9 (13.7 to 16.6) | 8.4 (8.3 to 11.0) | 11.0 (8.5 to 11.1) |
| HR (95% CI) | 1.16 (0.93 to 1.45) | 1.29 (0.93 to 1.81) | ||
| Decrease in PSA level ≥30% from baseline (95% CI), %a | 98.9 (96.0 to 99.9) | 98.1 (96.4 to 99.1) | 98.6 (92.6 to 100.0) | 97.3 (94.9 to 98.7) |
| Difference (95% CI), % | 0.8 (−1.2 to 2.8) | 1.4 (−1.8 to −4.5) | ||
| P value | .48 | .50 | ||
| Decrease in PSA level ≥50% from baseline (95% CI), %a | 93.8 (89.2 to 96.9) | 93.6 (90.9 to 95.6) | 94.5 (86.6 to 98.5) | 89.1 (85.3 to 92.3) |
| Difference (95% CI), % | 0.2 (−4.0 to 4.4) | 5.4 (−0.8 to 11.6) | ||
| P value | .92 | .16 | ||
| Decrease in PSA level ≥90% from baseline (95% CI), %a | 59.9 (52.3 to 67.2) | 60.9 (56.3 to 65.4) | 37.0 (26.0 to 49.1) | 49.8 (44.3 to 55.4) |
| Difference (95% CI), % | −1.1 (−9.5 to 7.4) | −12.9 (−25.2 to −0.6) | ||
| P value | .81 | .05 | ||
| Objective response rate (95% CI), %b | 67.5 (58.1 to 76.0) | 60.1 (54.2 to 65.9) | 50.0 (36.1 to 63.9) | 44.4 (37.7 to 51.3) |
| Difference (95% CI), % | 7.4 (−2.9 to 17.7) | 5.6 (−9.3 to 20.5) | ||
| P value | .17 | .46 | ||
Abbreviations: AFFIRM, Safety and Efficacy Study of MDV3100 in Patients With Castration-Resistant Prostate Cancer Who Have Been Previously Treated With Docetaxel-based Chemotherapy; HR, hazard ratio; NR, not reached; OS, overall survival; PREVAIL, A Safety and Efficacy Study of Oral MDV3100 in Chemotherapy-Naive Patients With Progressive Metastatic Prostate Cancer; PSA, prostate-specific antigen; rPFS, radiographic progression-free survival.
a
Includes confirmed and unconfirmed response.
b
Calculated by excluding nonevaluable patients (PREVAIL, n = 63 with new bone lesions and n = 180 without new bone lesions; and AFFIRM, n = 19 with new bone lesions and n = 115 without new bone lesions).