789P - Real-world (RW) duration of treatment in first-line maintenance (1Lm) niraparib monotherapy in epithelial ovarian cancer (EOC): CHAR1ZMA study

Background

RW data on 1Lm niraparib use in patients (pts) with EOC are sparse. The CHAR1ZMA study described treatment (tx) discontinuation for pts with EOC prescribed 1Lm niraparib monotherapy using a US RW database.

Methods

Eligibility criteria were previously described [1]. Pts were selected from the nationwide electronic health record-derived de-identified Flatiron Health database. Time to tx discontinuation (TTD; index [start of 1Lm niraparib] to 1Lm niraparib end date) was estimated via Kaplan-Meier methods. Results were stratified by early discontinuers (pts discontinued ≤90 days) and persisters (pts discontinued >90 days post-initiation/censored), and by breast cancer gene (BRCA)/homologous recombination deficiency (HRD) status.

Results

Among 414 EOC pts, 83% had stage III/IV disease, 26% were HR-deficient (HRd), and median age at index was 67 yrs. Median follow-up was 12.4 mo. Median TTD was 7.5 mo (95% confidence interval [CI] 5.9, 9.0) overall and increased by 4.9 mo to 12.4 mo (95% CI 10.3, 17.3) for persisters (n=296). Drug toxicity was cited as a reason for tx discontinuation in 67% of early discontinuers (n=118) and 22% of persisters (n=133) (Table). Disease progression was cited as a reason for tx discontinuation in 32% of early discontinuers and 74% of persisters. Dose modifications varied by discontinuation status (no dose modification was reported in 28% of persisters and 59% of early discontinuers). In the HRd subgroup, median TTD was 13.1 mo (95% CI 9.2, 22.2) overall (n=106), and increased by 9.1 mo to 22.2 mo (95% CI 13.5, not reached) for persisters (n=83).

Conclusions

This RW study demonstrates pts with EOC on 1Lm niraparib for >90 days have a much longer TTD than all pts. Effective clinical management of drug toxicity among 1Lm niraparib pts in the first 90 days of tx may help pts stay on tx and experience full therapeutic benefit.

Table: 789P

*BRCA/HRD not mutually exclusive groups. ^†Of pts who discontinued, pts may report ≥1 reason for discontinuation. ^‡Other includes, but is not limited to, disease-related symptoms not specific to tx.

[1] Coleman RL, et al. Presented at ESMO Gyn 2023 (43P).

Clinical trial identification

Editorial acknowledgement

Medical writing support was provided by Claire Kelly, PhD at Fishawack Indicia, UK, part of Fishawack Health Ltd. and funded by GSK. Statistical programming support was provided by Ramsanjay RK at GSK.

Legal entity responsible for the study

GSK.

Funding

GSK219843.

Disclosure

F. Backes: Financial Interests, Personal, Advisory Board: GSK, AstraZeneca, Clovis, Agenus, ImmunoGen, Merck, Eisai, Myriad; Financial Interests, Institutional, Principal Investigator: Natera, Merck, Eisai, Clovis, Immunogen, BeiGene. T. Boyle, J. Lim, J. Hartman, J.M. Schilder, J. Hurteau, A. Golembesky: Financial Interests, Personal, Full or part-time Employment: GSK. J. Perhanidis: Financial Interests, Personal, Full or part-time Employment: GSK; Financial Interests, Personal, Stocks/Shares: GSK; Financial Interests, Personal, Stocks or ownership: Boston Scientific. R. Salani: Financial Interests, Personal, Advisory Board: Merck, Seagen, Mersana; Financial Interests, Personal, Speaker’s Bureau: Merck; Financial Interests, Personal, Writing Engagement: UpToDate; Non-Financial Interests, Personal and Institutional, Principal Investigator: Genentech.