Table 3:
Secondary and exploratory efficacy endpoints for niraparib in patients with mCRPC
| Endpoint |
BRCA (n = 142) |
Measurable BRCA (n = 76) |
Non-BRCA (n = 81) |
|---|---|---|---|
| CTC response (CTC0) b , n/N (%) | 31/131 (23·7) | 18/71 (25.4) | 6/71 (8·5) |
| OS, mo, median (95% CI) | 13·01 (11·04 – 14·29) | 10·87 (9·49 – 13·77) | 9·63 (8·05 – 13·44) |
| rPFS, mo, median (95% CI) | 8·08 (5·55 – 8·38) | 5·52 (5·29 – 7·59) | 3·71 (1·97 – 5·49) |
| Time to radiographic progression, mo, median (95% CI) | 8·08 (5·75 – 8·97) | 5·55 (5·36 – 8·08) | 3·78 (2·00 – 5·55) |
| Time to PSA progression, mo, median (95% CI) | 5·13 (4·60 – 5·59) | 5·55 (4·60 – 8·31) | 3·65 (2·83 – 3·71) |
| Time to SSE, mo, median (95% CI) | 13·80 (10·41 – NE) | 13·80 (9·07 – NE) | 10·35 (8·18 – NE) |
| DOR, mo, median (95% CI) | 6·28 (3·65 – 9·23) | 5·55 (3·91 – 7·20) | 5·16 (2·14 – NE) |
|
CRRa, n/N (%)
(95% CI) |
82/142 (57·7) (49·2 – 66·0) |
46/76 (60·5) (48·7 – 71·6) |
12/81 (14·8) (7·9 – 24·5) |
|
CTC conversionc, n/N (%)
(95% CI) |
55/117 (47·0) (37·7 – 56·5) |
28/64 (43·8) (31·4 – 56·7) |
9/60 (15·0) (7·1 – 26·6) |
|
PSA50, n/N (%)
(95% CI) |
61/142 (43·0) (34·7 – 51·5) |
31/76 (40·8) (29·7 – 52·7) |
4/81 (4·9) (1·4 – 12·2) |
Defined as either an objective response for patients with measurable disease, CTC conversion (defined as CTC count ≥5 per 7·5 mL blood at baseline and <5 per 7·5 mL blood post-therapy nadir), or PSA50.
Defined per protocol and SAP as CTC=0 per 7·5 mL blood at 8 weeks post-baseline in patients with baseline CTC >0.
Among patients with baseline CTC ≥5.
mCRPC=metastatic castration-resistant breast cancer. BRCA=breast cancer gene. CTC=circulating tumour cells. CTC0=CTC count >0 at baseline to 0/7·5 mL blood at week 8. OS=overall survival. CI=confidence interval. rPFS=radiographic progression-free survival. PSA=prostate-specific antigen. SSE=symptomatic skeletal event. NE=not estimable. DOR=duration of objective response. CRR=composite response rate. CTC conversion=CTC count ≥5/7·5 mL blood at baseline to <5/7·5 mL blood at nadir. PSA50=≥50% decline in prostate-specific antigen.