Abstract 44P
Background
NOVA was a randomized Phase 3 trial assessing the efficacy of niraparib maintenance for patients (pts) with platinum-sensitive recurrent ovarian cancer (OC); overall survival (OS) was the secondary endpoint. The aim of this real-world (RW) study was to compare OS in BRCA wild-type (BRCAwt) pts with recurrent OC receiving second-line maintenance (2Lm) niraparib monotherapy or active surveillance (AS) to complement NOVA trial results.
Methods
This study used the US nationwide Flatiron Health de-identified electronic health record-derived database. Pts diagnosed with epithelial OC from 1 Jan 2011–31 May 2021 and completed 2L therapy from 1 Jan 2017–2 Mar 2022 were eligible for inclusion. Pts were assigned to niraparib 2Lm or AS cohorts according to their treatment scenario after end of 2L therapy (≤120 days). Follow-up was measured from index date (end of 2L non-maintenance therapy) until end of study (31 May 2022), last activity or death, whichever came first. A target trial emulation cloned inverse probability of censoring weighting (IPCW) methodology was selected a priori to minimize bias. IPCW median OS and hazard ratios (HR) for 2Lm vs AS were estimated with Kaplan-Meier curves and Cox regression models.
Results
Overall, 199 and 707 BRCAwt pts received niraparib 2Lm or were under AS, respectively. Most pt characteristics were similar across cohorts. Median follow-up was 15.6 and 9.3 months, and median OS was 24.1 (95% confidence interval [CI]: 20.9, 29.5) and 18.4 (95% CI: 15.1, 22.8) months for niraparib 2Lm and AS cohorts, respectively (HR: 0.77 [95% CI: 0.66, 0.89]). Table: 44P
Patient characteristics and follow-up before adjustment
| 2Lm (N=199) | 2L AS (N=707) | |
| Characteristics, n (%) | ||
| Age | ||
| 18–74 | 146 (73) | 498 (70) |
| ≥75 | 53 (27) | 209 (30) |
| Race | ||
| White | 132 (66) | 508 (72) |
| Black | 9 (5) | 42 (6) |
| Other | 52 (26) | 115 (16) |
| NR | 6 (3) | 42 (6) |
| Practice type | ||
| Community | 168 (84) | 574 (81) |
| Academic | 18 (9) | 118 (17) |
| Both | 13 (7) | 15 (2) |
| Histology | ||
| Serous | 156 (78) | 545 (77) |
| Other | 20 (10) | 68 (10) |
| NR | 23 (12) | 94 (13) |
| ECOG | ||
| 0–1 | 167 (84) | 505 (71) |
| 2–4 | 18 (9) | 93 (13) |
| NR | 14 (7) | 109 (15) |
| Stage | ||
| I–II | 21 (11) | 77 (11) |
| III | 103 (52) | 353 (50) |
| IV | 56 (28) | 203 (29) |
| NR | 19 (10) | 74 (10) |
| HRD | ||
| HRd | 10 (5) | 38 (5) |
| HRp | 7 (4) | 56 (8) |
| NR | 182 (91) | 613 (87) |
| Median follow-up, months (quartile 1, quartile 2) | 15.6 (9.1, 27.1) | 9.3 (3.2, 21.0) |
HRp, HR proficient; NR, not reported
Conclusions
This RW study provides supportive evidence of niraparib's OS benefit in BRCAwt pts in the 2Lm setting. Homologous recombination deficiency (HRD) testing in the RW is limited and prevented examination of BRCAwt + HR deficient (HRd) subgroup.
Editorial acknowledgement
Editorial support provided by Claire Kelly, Fishawack Health, funded by GSK.
Legal entity responsible for the study
GSK.
Funding
GSK (study 219306).
Disclosure
K.N. Moore: Financial Interests, Personal, Advisory Role: Aravive, AstraZeneca, Alkermes, Addi, Blueprint Pharma, Clovis, Elevar, Eisai, Genentech/Roche, GSK, Hengrui, ImmunoGen, Imab, Mersana, Myriad, Novartis, Mereo, OncXerna, OncoNova, Verastem, Sorrento, VBL Therapeutics; Financial Interests, Personal and Institutional, Advisory Role: Merck, Lilly; Financial Interests, Personal and Institutional, Research Grant: Merck, Lilly; Financial Interests, Institutional, Research Grant: PTC Therapeutics; Financial Interests, Personal, Member of the Board of Directors: Gynecologic Oncology Group F; Financial Interests, Personal, Other, Associate Director: Gynecologic Oncology Group Partners; Financial Interests, Personal, Research Grant: Verastem. J. Perhanidis: Financial Interests, Personal, Full or part-time Employment: GSK. L. Kalilani: Financial Interests, Personal, Full or part-time Employment: GSK. N. Zimmerman: Financial Interests, Personal, Full or part-time Employment: GSK; Financial Interests, Personal, Stocks/Shares: GSK. A. Golembesky: Financial Interests, Personal, Full or part-time Employment: GSK. R.L. Coleman: Financial Interests, Personal, Advisory Role: AstraZeneca, Clovis Oncology, Janssen, Merck, Roche/Genentech, Arrivive, Eisai, Novocure, Oncomed/Mateo, OncoQuest, OncoSec, GSK; Financial Interests, Personal and Institutional, Advisory Role: AbbVie; Financial Interests, Institutional, Research Grant: Genmab, V-Foundation.