Table 2.
Primary and secondary efficacy endpoints (mITT population)
| Radium-223 monotherapy (n = 19) | Radium-223 + abiraterone/prednisone (n = 22) | Radium-223 + enzalutamide (n = 22) | |
|---|---|---|---|
| BSLA RR at week 24, % (80% CI),a P value |
22 (10-40); P = 0.0109b | 58 (41-74); P < 0.0001b | 50 (32-68); P < 0.0001b |
| Median rPFS, months (80% CI)c | 4 (4-12) | NE (19-NE) | NE (10-NE) |
| Median time to radiologic disease (non-bone) progression, months (80% CI)c | 5 (4-NE) | NE (NE-NE) | NE (NE-NE) |
| Median time to radiologic bone progression, months (80% CI)c | 12 (4-12) | NE (NE-NE) | NE (NE-NE) |
| Patients with an SSE, n (%) | 6 (32) | 7 (32) | 7 (32) |
| Median SSE-FS, months (80% CI) | 12 (10-25) | NE (17-NE) | 20 (12-28) |
| Median time to first SSE, months (80% CI) | NE (13-NE) | NE (17-NE) | NE (20-NE) |
| Median OS, months (80% CI) | 36 (21-41) | 38 (36-NE) | 30 (27-NE) |
BSLA, bone scan lesion area; CI, confidence interval; mITT, modified intention-to-treat; NE, not estimable; OS, overall survival; rPFS, radiologic progression-free survival; RR, response rate; SSE, symptomatic skeletal event; SSE-FS, SSE-free survival.
a
Imaging population: radium-223 + abiraterone/prednisone, n = 19; radium-223 + enzalutamide, n = 16; radium-223 monotherapy, n = 18.
b
Test of the null hypothesis of BSLA RR ≤5% at week 24 using an exact single-arm binomial test in each treatment group with one-sided alpha = 0.10.
c
Central review.