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BACKGROUND: The authors performed a meta‐analysis to better quantify the benefit of maintenance poly(ADP‐ribose) polymerase inhibitor (PARPi) therapy to inform practice in platinum‐sensitive, recurrent, high‐grade ovarian cancer for patient subsets with the following characteristics: germline BRCA mutation (gBRCAm), somatic BRCA mutation (sBRCAm), wild‐type BRCA but homologous recombinant‐deficient (HRD), homologous recombinant‐proficient (HRP), and baseline clinical prognostic characteristics. METHODS: Randomized trials comparing a PARPi versus placebo as maintenance treatment were identified from electronic databases. Treatment estimates of progression‐free survival were pooled across trials using the inverse variance weighted method. RESULTS: Four trials included 972 patients who received a PARPi (olaparib, 31%; niraparib, 35%; or rucaparib, 34%) and 530 patients who received placebo. For patients who had germline BRCA1 mutation (gBRCAm1) (N = 471), the hazard ratio (HR) was 0.29 (95% CI, 0.23‐0.37); for those who had germline BRCA2 mutation (gBRCAm2) (N = 236), the HR was 0.26 (95% CI, 0.17‐0.39); and, for those who had sBRCAm (N = 123), the HR was 0.22 (95% CI, 0.12‐0.41). The treatment effect was similar between the gBRCAm and sBRCAm subsets (P =.48). In patients who had wild‐type BRCA HRD tumors (excluding sBRCAm; N = 309), the HR was 0.41 (95% CI, 0.31‐0.56); and, in those who had wild‐type BRCA HRP tumors (N = 346), the HR was 0.64 (95% CI, 0.49‐0.83). The relative treatment effect was greater for the BRCAm versus HRD (P =.03), BRCAm versus HRP (P <.00001), and HRD versus HRP (P <.00001) subsets. There was no difference in benefit based on age, response after recent chemotherapy, and prior bevacizumab. CONCLUSIONS: In platinum‐sensitive, recurrent, high‐grade ovarian cancer, maintenance PARPi improves progression‐free survival for all patient subsets. PARPi therapy has a similar magnitude of benefit for sBRCAm and gBRCAm. Although patients with BRCAm derive the greatest benefit, the absence of a BRCAm or HRD could not be used to exclude patients from maintenance PARPi therapy. BRCA mutation status is able to predict for the magnitude of PARP inhibitor benefit in platinum‐sensitive recurrent high‐grade ovarian tumor. However, the absence of a BRCA mutation or homologous recombinant deficiency in high‐grade ovarian tumor cannot be used to exclude patients from such therapy. [ABSTRACT FROM AUTHOR]

Background: Olaparib, a poly(ADP-ribose) polymerase (PARP) inhibitor, has previously shown efficacy in a phase 2 study when given in capsule formulation to all-comer patients with platinum-sensitive, relapsed high-grade serous ovarian cancer. We aimed to confirm these findings in patients with a BRCA1 or BRCA2 (BRCA1/2) mutation using a tablet formulation of olaparib.Methods: This international, multicentre, double-blind, randomised, placebo-controlled, phase 3 trial evaluated olaparib tablet maintenance treatment in platinum-sensitive, relapsed ovarian cancer patients with a BRCA1/2 mutation who had received at least two lines of previous chemotherapy. Eligible patients were aged 18 years or older with an Eastern Cooperative Oncology Group performance status at baseline of 0-1 and histologically confirmed, relapsed, high-grade serous ovarian cancer or high-grade endometrioid cancer, including primary peritoneal or fallopian tube cancer. Patients were randomly assigned 2:1 to olaparib (300 mg in two 150 mg tablets, twice daily) or matching placebo tablets using an interactive voice and web response system. Randomisation was stratified by response to previous platinum chemotherapy (complete vs partial) and length of platinum-free interval (6-12 months vs ≥12 months) and treatment assignment was masked for patients, those giving the interventions, data collectors, and data analysers. The primary endpoint was investigator-assessed progression-free survival and we report the primary analysis from this ongoing study. The efficacy analyses were done on the intention-to-treat population; safety analyses included patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, number NCT01874353, and is ongoing and no longer recruiting patients.Findings: Between Sept 3, 2013, and Nov 21, 2014, we enrolled 295 eligible patients who were randomly assigned to receive olaparib (n=196) or placebo (n=99). One patient in the olaparib group was randomised in error and did not receive study treatment. Investigator-assessed median progression-free survival was significantly longer with olaparib (19·1 months [95% CI 16·3-25·7]) than with placebo (5·5 months [5·2-5·8]; hazard ratio [HR] 0·30 [95% CI 0·22-0·41], p<0·0001). The most common adverse events of grade 3 or worse severity were anaemia (38 [19%] of 195 patients in the olaparib group vs two [2%] of 99 patients in the placebo group), fatigue or asthenia (eight [4%] vs two [2%]), and neutropenia (ten [5%] vs four [4%]). Serious adverse events were experienced by 35 (18%) patients in the olaparib group and eight (8%) patients in the placebo group. The most common in the olaparib group were anaemia (seven [4%] patients), abdominal pain (three [2%] patients), and intestinal obstruction (three [2%] patients). The most common in the placebo group were constipation (two [2%] patients) and intestinal obstruction (two [2%] patients). One (1%) patient in the olaparib group had a treatment-related adverse event (acute myeloid leukaemia) with an outcome of death.Interpretation: Olaparib tablet maintenance treatment provided a significant progression-free survival improvement with no detrimental effect on quality of life in patients with platinum-sensitive, relapsed ovarian cancer and a BRCA1/2 mutation. Apart from anaemia, toxicities with olaparib were low grade and manageable.Funding: AstraZeneca. [ABSTRACT FROM AUTHOR]

Background: In patients with platinum-sensitive recurrent serous ovarian cancer, maintenance monotherapy with the PARP inhibitor olaparib significantly improves progression-free survival versus placebo. We assessed the effect of maintenance olaparib on overall survival in patients with platinum-sensitive recurrent serous ovarian cancer, including those with BRCA1 and BRCA2 mutations (BRCAm).Methods: In this randomised, placebo-controlled, double-blind, phase 2 trial involving 82 sites across 16 countries, patients with platinum-sensitive recurrent serous ovarian cancer who had received two or more courses of platinum-based chemotherapy and had responded to their latest regimen were randomly assigned (1:1) using a computer-generated sequence to receive oral maintenance olaparib (as capsules; 400 mg twice a day) or a matching placebo by an interactive voice response system. Patients were stratified by ancestry, time to progression on penultimate platinum, and response to most recent platinum. Patients and investigators were masked to treatment assignment by the use of unique identifiers generated during randomisation. The primary endpoint of the trial was progression-free survival. In this updated analysis, we present data for overall survival, a secondary endpoint, from the third data analysis after more than 5 years' follow-up (intention-to-treat population). We did the updated overall survival analysis, described in this Article at 77% data maturity, using a two-sided α of 0·95%. As the study was not powered to assess overall survival, this analysis should be regarded as descriptive and the p values are nominal. We analysed randomly assigned patients for overall survival and all patients who received at least one dose of treatment for safety. This trial is ongoing and is registered with ClinicalTrials.gov, number NCT00753545.Findings: Between Aug 28, 2008, and Feb 9, 2010, 265 patients were randomly assigned to olaparib (n=136) or placebo (n=129). 136 patients had deleterious BRCAm. The data cutoff for this analysis was Sept 30, 2015. An overall survival advantage was seen with maintenance olaparib versus placebo in all patients (hazard ratio [HR] 0·73 [95% CI 0·55-0·96]; nominal p=0·025, which did not meet the required threshold for statistical significance [p<0·0095]; median overall survival was 29·8 months [95% CI 26·9-35·7] for those treated with olaparib vs 27·8 months [24·9-33·7] for those treated with placebo), and in patients with BRCAm (HR 0·62 [95% CI 0·41-0·94] nominal p=0·025; 34·9 months [95% CI 29·2-54·6] vs 30·2 months [23·1-40·7]). The overall survival data in patients with BRCA wild-type were HR 0·83 (95% CI 0·55-1·24, nominal p=0·37; 24·5 months [19·8-35·0] for those treated with olaparib vs 26·6 months [23·1-32·5] for those treated with placebo). 11 (15%) of 74 patients with BRCAm received maintenance olaparib for 5 years or more. Overall, common grade 3 or worse adverse events in the olaparib and placebo groups were fatigue (11 [8%] of 136 patients vs four [3%] of 128) and anaemia (eight [6%] vs one [1%]). 30 (22%) of 136 patients in the olaparib group and 11 (9%) of 128 patients in the placebo group reported serious adverse events. In patients treated for 2 years or more, adverse events in the olaparib and placebo groups included low-grade nausea (24 [75%] of 32 patients vs two [40%] of five), fatigue (18 [56%] of 32 vs two [40%] of five), vomiting (12 [38%] of 32 vs zero), and anaemia (eight [25%] of 32 vs one [20%] of five); generally, events were initially reported during the first 2 years of treatment.Interpretation: Despite not reaching statistical significance, patients with BRCA-mutated platinum-sensitive recurrent serous ovarian cancer receiving olaparib maintenance monotherapy after platinum-based chemotherapy appeared to have longer overall survival, supporting the reported progression-free survival benefit. Clinically useful long-term exposure to olaparib was seen with no new safety signals. Taken together, these data support both the long-term clinical benefit and tolerability of maintenance olaparib in patients with BRCA-mutated platinum-sensitive recurrent serous ovarian cancer.Funding: AstraZeneca. [ABSTRACT FROM AUTHOR]

Background: Maintenance treatment with the oral poly(adenosine diphosphate ribose) polymerase (PARP) inhibitor olaparib (Lynparza) in Study 19 (study number, D0810C00019; ClinicalTrials.gov identifier, NCT00753545) significantly improved progression-free survival in comparison with a placebo for patients with platinum-sensitive, relapsed serous ovarian cancer with a BRCA1/2 mutation (BRCAm), but an interim analysis revealed no statistically significant overall survival (OS) benefit. However, 23% of the patients receiving the placebo switched to a PARP inhibitor after progression. To investigate whether this had a confounding effect on OS, this article reports an exploratory post hoc analysis that excluded all patients from sites where 1 or more placebo patients received postprogression PARP inhibitor treatment.Methods: In Study 19, 136 of the 265 patients receiving olaparib or a placebo had a BRCAm. Sixteen patients treated at 11 of the 82 investigational sites received a PARP inhibitor after progression; these sites were excluded from this analysis, and 97 BRCAm patients at 50 sites were included. OS was assessed with a Cox proportional hazards model analogous to the primary study analysis. A supporting rank-preserving structural failure time (RPSFT) model analysis was undertaken for all 136 BRCAm patients.Results: The OS hazard ratio (HR) was 0.52 (95% confidence interval [CI], 0.28-0.97) for the 97 BRCAm patients, whereas for the interim OS analysis with all 136 BRCAm patients, it was 0.73 (95% CI, 0.45-1.17). The supportive RPSFT analysis HR was approximately 0.66.Conclusions: The numerical improvement in the OS HR suggests that in Study 19, postprogression PARP inhibitor treatment had a confounding influence on the interim OS analysis for BRCAm patients. There is a degree of uncertainty due to the small sample size and the lack of data maturity. Cancer 2016;122:1844-52. © 2016 American Cancer Society. [ABSTRACT FROM AUTHOR]

The discovery that PARP inhibitors block an essential pathway of DNA repair in cells harbouring a BRCA mutation has opened up a new therapeutic avenue for high-grade ovarian cancers. BRCA1 and BRCA2 proteins are essential for high-fidelity repair of double-strand breaks of DNA through the homologous recombination repair (HRR) pathway. Deficiency in HRR (HRD) is a target for PARP inhibitors. The first PARP inhibitor, olaparib, has now been licensed for BRCA-mutated ovarian cancers. While mutated BRCA genes are individually most commonly associated with HRD other essential HRR proteins may be mutated or functionally deficient potentially widening the therapeutic opportunities for PARP inhibitors. HRD is the first phenotypically defined predictive marker for therapy with PARP inhibitors in ovarian cancer. Several different PARP inhibitors are being trialled in ovarian cancer and this class of drugs has been shown to be a new selective therapy for high-grade ovarian cancer. Around 20% of high-grade serous ovarian cancers harbour germline or somatic BRCA mutations and testing for BRCA mutations should be incorporated into routine clinical practice. The expanded use of PARP inhibitors in HRD deficient (non-BRCA mutant) tumours using a signature of HRD in clinical practice requires validation. [ABSTRACT FROM AUTHOR]

Background: Rucaparib is an orally available potent selective small-molecule inhibitor of poly(ADP-ribose) polymerase (PARP) 1 and 2. Rucaparib induces synthetic lethality in cancer cells defective in the homologous recombination repair pathway including BRCA-1/2. We investigated the efficacy and safety of single-agent rucaparib in germline (g) BRCA mutation carriers with advanced breast and ovarian cancers.Methods: Phase II, open-label, multicentre trial of rucaparib in proven BRCA-1/2 mutation carriers with advanced breast and or ovarian cancer, WHO PS 0-1 and normal organ function. Intravenous (i.v.) and subsequently oral rucaparib were assessed, using a range of dosing schedules, to determine the safety, tolerability, dose-limiting toxic effects and pharmacodynamic (PD) and pharmacokinetic (PK) profiles.Results: Rucaparib was well tolerated in patients up to doses of 480 mg per day and is a potent inhibitor of PARP, with sustained inhibition ⩾24 h after single doses. The i.v. rucaparib (intermittent dosing schedule) resulted in an objective response rate (ORR) of only 2% but with 41% (18 out of 44) patients achieved stable disease for ⩾12 weeks and 3 patients maintaining disease stabilisation for >52 weeks. The ORR for oral rucaparib (across all six dose levels) was 15%. In the oral cohorts, 81% (22 out of 27) of the patients had ovarian cancer and 12 out of 13, who were dosed continuously, achieved RECIST complete response/partial response (CR/PR) or stable disease (SD) ⩾12 weeks, with a median duration of response of 179 days (range 84-567 days).Conclusions: Rucaparib is well tolerated and results in high levels of PARP inhibition in surrogate tissues even at the lowest dose levels. Rucaparib is active in gBRCA-mutant ovarian cancer and this activity correlates with platinum-free interval. The key lessons learned from this study is that continuous rucaparib dosing is required for optimal response, the recommended phase 2 dose (RP2D) for continuous oral scheduling has not been established and requires further exploration and, thirdly, the use of a PD biomarker to evaluate dose-response has its limitations. [ABSTRACT FROM AUTHOR]

Background: Olaparib, a poly (ADP-ribose) polymerase (PARP) inhibitor, has previously been shown to extend progression-free survival versus placebo when given to patients with relapsed high-grade serous or endometrioid ovarian cancer who were platinum sensitive and who had a BRCA1 or BRCA2 (BRCA1/2) mutation, as part of the SOLO2/ENGOT-Ov21 trial. The aim of this final analysis is to investigate the effect of olaparib on overall survival.Methods: This double-blind, randomised, placebo-controlled, phase 3 trial was done across 123 medical centres in 16 countries. Eligible patients were aged 18 years or older, had an Eastern Cooperative Oncology Group performance status at baseline of 0-1, had histologically confirmed, relapsed, high-grade serous or high-grade endometrioid ovarian cancer, including primary peritoneal or fallopian tube cancer, and had received two or more previous platinum regimens. Patients were randomly assigned (2:1) to receive olaparib tablets (300 mg in two 150 mg tablets twice daily) or matching placebo tablets using an interactive web or voice-response system. Stratification was by response to previous chemotherapy and length of platinum-free interval. Treatment assignment was masked to patients, treatment providers, and data assessors. The primary endpoint of progression-free survival has been reported previously. Overall survival was a key secondary endpoint and was analysed in all patients as randomly allocated. Safety was assessed in all patients who received at least one treatment dose. This trial is registered with ClinicalTrials.gov, NCT01874353, and is no longer recruiting patients.Findings: Between Sept 3, 2013 and Nov 21, 2014, 295 patients were enrolled. Patients were randomly assigned to receive either olaparib (n=196 [66%]) or placebo (n=99 [34%]). One patient, randomised in error, did not receive olaparib. Median follow-up was 65·7 months (IQR 63·6-69·3) with olaparib and 64·5 months (63·4-68·7) with placebo. Median overall survival was 51·7 months (95% CI 41·5-59·1) with olaparib and 38·8 months (31·4-48·6) with placebo (hazard ratio 0·74 [95% CI 0·54-1·00]; p=0·054), unadjusted for the 38% of patients in the placebo group who received subsequent PARP inhibitor therapy. The most common grade 3 or worse treatment-emergent adverse event was anaemia (which occurred in 41 [21%] of 195 patients in the olaparib group and two [2%] of 99 patients in the placebo group). Serious treatment-emergent adverse events were reported in 50 (26%) of 195 patients receiving olaparib and eight (8%) of 99 patients receiving placebo. Treatment-emergent adverse events with a fatal outcome occurred in eight (4%) of the 195 patients receiving olaparib, six of which were judged to be treatment-related (attributed to myelodysplastic syndrome [n=3] and acute myeloid leukaemia [n=3]).Interpretation: Olaparib provided a median overall survival benefit of 12·9 months compared with placebo in patients with platinum-sensitive, relapsed ovarian cancer and a BRCA1/2 mutation. Although statistical significance was not reached, these findings are arguably clinically meaningful and support the use of maintenance olaparib in these patients.Funding: AstraZeneca and Merck. [ABSTRACT FROM AUTHOR]

The impact of maintenance therapy with PARP inhibitors (PARPi) on progression-free survival (PFS) in patients with BRCA mutations and platinum-sensitive recurrent ovarian cancer (PSROC) varies widely. Individual prognostic factors do not reliably distinguish patients who progress early from those who have durable benefit. We developed and validated a prognostic nomogram to predict PFS in these patients. The nomogram was developed using data from a training patient cohort with BRCA mutations and high-grade serous PSROC on the placebo arm of two maintenance therapy trials, Study 19 and SOLO2/ENGOT-ov21. We performed multivariable Cox regression analysis based on pre-treatment characteristics to develop a nomogram that predicts PFS. We assessed the discrimination and validation of the nomogram in independent validation patient cohorts treated with maintenance olaparib. The nomogram includes four PFS predictors: CA-125 at randomisation, platinum-free interval, presence of measurable disease and number of prior lines of platinum therapy. In the training (placebo) cohort (internal validation C-index 0.64), median PFS in the model-predicted good, intermediate and poor-risk groups was: 7.7 (95% CI 5.3–11.3), 5.4 (4.8–5.8) and 2.9 (2.8–4.4) months, respectively. In the validation (olaparib) cohort (C-index 0.71), median PFS in the model-predicted good, intermediate and poor-risk groups was: not reached, 16.6 (13.1–22.4) and 8.3 (7.1–10.8) months, respectively. The nomogram showed good calibration in the validation cohort (calibration plot). This nomogram can be used to predict PFS and counsel patients with BRCA mutations and PSROC prior to maintenance olaparib and for stratification of patients in trials of maintenance therapies. • The impact of maintenance PARPi on PFS in women with BRCA-mutant PSROC varies widely. • Our nomogram includes CA-125, PFI, measurable disease and prior platinum therapy. • Our nomogram and online tool demonstrates good discrimination and is well-calibrated. • Our nomogram can help to predict PFS and counsel patients prior to olaparib therapy. [ABSTRACT FROM AUTHOR]

Limited evidence exists to support CA-125 as a valid surrogate biomarker for progression in patients with ovarian cancer on maintenance PARP inhibitor (PARPi) therapy. We aimed to assess the concordance between CA-125 and Response Evaluation Criteria in Solid Tumours (RECIST) criteria for progression in patients with BRCA mutations on maintenance PARPi or placebo. We extracted data on progression as defined by Gynecologic Cancer InterGroup CA-125, investigator- and independent central-assessed RECIST from the SOLO2/ENGOT-ov21(NCT01874353) trial. We excluded those with progression other than by RECIST, progression on date of randomisation, and no repeat CA-125 beyond baseline. We evaluated the concordance between CA-125 progression and RECIST progression, and assessed the negative (NPV) and positive predictive value (PPV). Of 295 randomised patients, 275 (184 olaparib, 91 placebo) were included. 171 patients had investigator-assessed RECIST progression. Of 80 patients with CA-125 progression, 77 had concordant RECIST progression (PPV 96%, 95% confidence interval 90–99%). Of 195 patients without CA-125 progression, 94 had RECIST progression (NPV 52%, 45–59%). Within treatment arms, PPV was similar (olaparib: 95% [84–99%], placebo: 97% [87–100%]) but NPV was lower in patients on placebo (olaparib: 60% [52–68%], placebo: 30% [20–44%]). Of 94 patients with RECIST but without CA-125 progression, 64 (68%) had CA-125 that remained within normal range. We observed similar findings using independent-assessed RECIST. Almost half the patients without CA-125 progression had RECIST progression, and most of these had CA-125 within the normal range. Regular computed tomography imaging should be considered as part of surveillance in patients treated with or without maintenance olaparib rather than relying on CA-125 alone. • There is poor concordance between CA-125 non-PD and RECIST progression. • Half the patients without CA-125 PD had RECIST PD, most had normal CA-125 levels. • CT imaging to be considered as part of follow-up rather than relying on CA-125 alone. [ABSTRACT FROM AUTHOR]

Objectives: The OPINION study (NCT03402841) demonstrated the activity of maintenance olaparib in patients (pts) with platinum-sensitive relapsed ovarian cancer (PSR OC) without a germline BRCA1 / BRCA2 mutation (non-g BRCA m), with an overall median progression-free survival (PFS) of 9.2 months (mo) (Poveda et al. ASCO 2021). We further explored clinical and molecular characteristics in pts with long-term (LT) and short-term (ST) PFS. Methods: Pts with non-g BRCA m PSR OC and ≥2 prior lines of platinum-based chemotherapy (PBC) incomplete/partial response (CR/PR) to their last PBC received maintenance olaparib (300 mg bid) until progression/unacceptable toxicity. Here, pts were grouped by time from the first dose until disease progression (RECIST v1.1) or death: >18 mo for the LT group and <4 mo for the ST group (chosen based on radiologic scan timings and follow up). Pts who discontinued the study >18 mo after the first dose were also in the LT group. Samples were analyzed using the Myriad myChoice HRD plus and BRACAnalysis CDx assays. Molecular analyses included: tumor BRCA m (t BRCA m); somatic BRCA m (s BRCA m), defined as the presence of a t BRCA m and no g BRCA m; homologous recombination deficiency (HRD), defined as a genomic instability score ≥42 and/or t BRCA m; homologous recombination repair (HRR) gene mutations, excluding BRCA m (non -BRCA HRRm), based on a prespecified 13-gene panel; and TP53 mutation status. Results: Of 279 pts in OPINION, 67 (24%) and 65 (23%) had LT and ST PFS, respectively. At diagnosis, 45/67 pts (67%) in the LT group had FIGO stage III and 15 (22%) had stage IV disease; 47/65 (72%) in the ST group had stage III and 12 (18%) had stage IV disease. Median (range) prior PBC regimens was 2 (2-5) and 2 (2-6) in the LT and ST groups, respectively. About 34/67 (51%) and 12/65 (18%) pts achieved CR to their last PBC, and 33/67 (49%) and 52/65 (80%) had PR in the LT and ST groups, respectively; 48/67 (72%) and 42/65 (65%) had a platinum-free interval of ≥12 mo in the LT and ST groups, respectively. Fifteen out of 67 (22%) and 5/65 pts (8%) were found to have a t BRCA m in the LT and ST groups, respectively; 47/67 (70%) and 25/65 pts (40%) had HRD-positive tumors. Fifteen (22%) and 5 (8%) pts had a non- BRCA HRRm in the LT and ST groups, respectively, although 65% of pts with a non- BRCA HRRm had HRD-positive tumors. Twenty-five (37%) and 32 (49%) had TP53 -disruptive mutations in the LT and ST groups, respectively. Overlap between t BRCA m, HRD, non- BRCA HRRm (including most frequently mutated genes), and TP53 mutations is shown in the Figure. Conclusions: Pts with LT PFS (>18 mo) in OPINION more commonly had HRD-positive tumors, with or without a t BRCA m, than pts with ST PFS (<4 mo), consistent with results showing longer PFS among pts with HRD-positive tumors in the overall population. A higher proportion of pts with LT than ST PFS achieved CR to their last PBC. However, pts could achieve LT PFS regardless of clinical and molecular factors, reinforcing the benefit of maintenance PARP inhibition in non-g BRCA m PSR OC. [ABSTRACT FROM AUTHOR]