RIF1 acts in DNA repair through phosphopeptide recognition of 53BP1.

The chromatin-binding protein 53BP1 promotes DNA repair by orchestrating the recruitment of downstream effectors including PTIP, RIF1, and shieldin to DNA double-strand break sites. While we know how PTIP recognizes 53BP1, the molecular details of RIF1 recruitment to DNA-damage sites remains undefined. Here, we report that RIF1 is a phosphopeptide-binding protein that directly interacts with three phosphorylated 53BP1 epitopes. The RIF1-binding sites on 53BP1 share an essential LxL motif followed by two closely apposed phosphorylated residues. Simultaneous mutation of these sites on 53BP1 abrogates RIF1 accumulation into ionizing-radiation-induced foci, but surprisingly, only fully compromises 53BP1-dependent DNA repair when an alternative mode of shieldin recruitment to DNA-damage sites is also disabled. Intriguingly, this alternative mode of recruitment still depends on RIF1 but does not require its interaction with 53BP1. RIF1 therefore employs phosphopeptide recognition to promote DNA repair but also modifies shieldin action independently of 53BP1 binding.

Top advances of the year: Ovarian cancer.

Although cure rates remain low and effective screening strategies are elusive, the recent advances in systemic therapies over the past year highlighted in this review have prolonged survival for women with ovarian cancer. In 2022, the first antibody-drug conjugate for platinum-resistant ovarian cancer received accelerated US Food and Drug Administration (FDA) approval. Confirmatory studies examining the efficacy of mirvetuximab and other antibody-drug conjugates are underway. In the upfront setting, the first data establishing an overall survival benefit from poly(ADP-ribose) polymerase inhibitor maintenance was demonstrated after a 7-year follow-up period. In contrast, long-term updates from poly(ADP-ribose) polymerase inhibitor trials in the noncurative setting reported survival detriments, and the FDA withdrew the respective indications. Several trials attempted to improve upon the standard of care for platinum-sensitive ovarian carcinoma and those with rare ovarian cancer histologies (carcinosarcoma, clear cell carcinoma) but failed to demonstrate a clinically or statistically meaningful benefit. This leaves the open question of how to further optimize systemic therapy for advanced ovarian carcinoma to improve long-term survival and cure rates.

The efficacy and safety of PARP inhibitors in mCRPC with HRR mutation in second-line treatment: a systematic review and bayesian network meta-analysis.

BACKGROUND: Poly (ADP- ribose) polymerase inhibitors (PARPi) has been increasingly adopted for metastatic castration-resistance prostate cancer (mCRPC) patients with homologous recombination repair deficiency (HRD). However, it is unclear which PARPi is optimal in mCRPC patients with HRD in 2nd -line setting. METHOD: We conducted a systematic review of trials regarding PARPi- based therapies on mCRPC in 2nd -line setting and performed a Bayesian network meta-analysis (NMA). Radiographic progression-free survival (rPFS) was assessed as primary outcome. PSA response and adverse events (AEs) were evaluated as secondary outcomes. Subgroup analyses were performed according to specific genetic mutation. RESULTS: Four RCTs comprised of 1024 patients (763 harbored homologous recombination repair (HRR) mutations) were identified for quantitative analysis. Regarding rPFS, olaparib monotherapy, rucaparib and cediranib plus olaparib showed significant improvement compared with ARAT. Olaparib plus cediranib had the highest surface under cumulative ranking curve (SUCRA) scores (87.5%) for rPFS, followed by rucaparib, olaparib and olaparib plus abiraterone acetate prednisone. For patients with BRCA 1/2 mutations, olaparib associated with the highest probability (98.1%) of improved rPFS. For patients with BRCA-2 mutations, olaparib and olaparib plus cediranib had similar efficacy. However, neither olaparib nor rucaparib showed significant superior effectiveness to androgen receptor-axis-targeted therapy (ARAT) in patients with ATM mutations. For safety, olaparib showed significantly lower ≥ 3 AE rate compared with cediranib plus olaparib (RR: 0.72, 95% CI: 0.51, 0.97), while olaparib plus cediranib was associated with the highest risk of all-grade AE. CONCLUSION: PARPi-based therapy showed considerable efficacy for mCRPC patients with HRD in 2nd -line setting. However, patients should be treated accordingly based on their genetic background as well as the efficacy and safety of the selected regimen. TRIAL REGISTRATION: CRD42023454079.

Evaluation of Homologous Recombination Deficiency in Ovarian Cancer.

OPINION STATEMENT: Homologous recombination deficiency (HRD) is an important biomarker guiding selection of ovarian cancer patients who will derive the most benefit from poly(ADP-ribose) polymerase inhibitors (PARPi). HRD prevents cells from repairing double-stranded DNA damage with high fidelity, PARPis limit single-stranded repair, and together these deficits induce synthetic lethality. Germline or somatic BRCA mutations represent the narrowest definition of HRD, but do not reflect all patients who will have a durable PARPi response. HRD can also be defined by its downstream consequences, which are measured by different metrics depending on the test used. Ideally, all patients will undergo genetic counseling and germline testing shortly after diagnosis and have somatic testing sent once an adequate tumor sample is available. Should barriers to one test be higher, pursuing germline testing with reflex to somatic testing for BRCA wildtype patients or somatic testing first strategies are both evidence-based. Ultimately both tests offer complementary information, germline testing should be pursued for any patient with a history of ovarian cancer, and somatic testing is valuable at recurrence if not performed in the upfront setting. There is a paucity of data to suggest superiority of one germline or somatic assay; therefore, selection should optimize turnaround time, cost to patients, preferred result format, and logistical burden. Each clinic should implement a standard testing strategy for all ovarian cancer patients that ensures HRD status is known at the time of upfront chemotherapy completion to facilitate comprehensive counseling about anticipated maintenance PARPi benefit.

Prevalence of germline BRCA1/2 pathogenic variants in Japanese patients treated with castration-resistant prostate cancer and efficacy of CRPC treatment in real-world clinical practice.

OBJECTIVE: The companion diagnosis for olaparib, a poly (ADP-ribose) polymerase inhibitor for prostate cancer, aims to detect BRCA1/2 gene variants. In clinical practice, the frequency of germline BRCA1/2 variants in patients receiving castration-resistant prostate cancer treatment is unknown. We aimed to evaluate the prevalence of germline BRCA1/2 variants and their relationship to prognosis and treatment efficacy in castration-resistant prostate cancer. METHODS: Between June 2021 and 2023, 92 patients receiving castration-resistant prostate cancer treatment were examined for germline BRCA1/2 variants using BRACAnalysis CDx®. Furthermore, the associations between BRCA1/2 pathogenic variants and clinical outcomes were assessed. RESULTS: Of the 92 patients referred for genetic testing, 6 (6.5%) carried germline pathogenic variants in BRCA1/2. The BRCA2 variant was the most frequent (n = 5), followed by BRCA1 variant (n = 1). Among the five variants in BRCA2, the p.Asp427Thrfs*3 variant was identified for the first time in prostate cancer. Overall survival from castration-resistant prostate cancer for patients with BRCA1/2 variants was significantly shorter than for patients without BRCA1/2 variants (P = 0.043). Progression-free survival of androgen receptor signaling inhibitors for patients with BRCA1/2 variants was significantly shorter than for those without (P = 0.003). Progression-free survival of taxane chemotherapy was significantly shorter in patients with BRCA1/2 variants than in those without (P = 0.0149). CONCLUSIONS: In clinical practice, 6.5% of patients treated with castration-resistant prostate cancer carried germline BRCA1/2 pathogenic variants. Japanese castration-resistant prostate cancer patients with germline BRCA1/2 mutants have a poor prognosis and may be less responsive to treatment with androgen receptor signaling inhibitors and taxane-based chemotherapy for castration-resistant prostate cancer.

CA-125 KELIM as an Alternative Predictive Tool to Identify Which Patients Can Benefit from PARPi in High-Grade Serous Advanced Ovarian Cancer: A Retrospective Pilot Diagnostic Accuracy Study.

BRCA mutation and homologous recombination deficiency (HRD) are the criteria for the administration of PARP inhibitor (PARPi) maintenance therapy. It is known that PARPi efficacy is related to platinum sensitivity and that the latter can be demonstrated from the CA-125 elimination rate constant (KELIM). This study aims to investigate if KELIM can be another tool in the identification of patients that could be benefit from PARPi therapy. Retrospective analysis of patients with high-grade serous advanced ovarian cancer that underwent cytoreduction and was further tested for HRD status. The HRD status was tested either by myChoice HRD CDx assay or by RediScore assay. KELIM score was measured in both neoadjuvant and adjuvant settings with the online tool biomarker-kinetics.org. A total of 39 patients had available data for estimating both HRD status and KELIM score. When assuming KELIM as a binary index test with the value 1 as the cut-off point, the sensitivity was 0.86, 95% CI (0.64-0.97) and the specificity was 0.83, 95% CI (0.59-0.96). On the other hand, when assuming KELIM as a continuous index test, the area under the curve (AUC) was 81% and the optimal threshold, using the Youden index, was identified as 1.03 with a sensitivity of 85.7% and a specificity of 83.3%. KELIM score seems to be a new, cheaper, and faster tool to identify patients that can benefit from PARPi maintenance therapy.

Prospective evaluation of the tolerability and efficacy of niraparib dosing based on baseline body weight and platelet count: Results from the PRIMA/ENGOT-OV26/GOG-3012 trial.

BACKGROUND: The PRIMA/ENGOT-OV26/GOG-3012 (NCT02655016) trial was amended to prospectively evaluate the safety and efficacy of an individualized starting dose (ISD) regimen of niraparib for first-line maintenance therapy in patients with newly diagnosed advanced ovarian cancer. METHODS: In the phase 3 PRIMA trial, patients with newly diagnosed advanced ovarian cancer with a complete/partial response to first-line platinum-based chemotherapy (N = 733) were initially treated with a fixed starting dose (FSD) regimen of 300 mg once daily. Subsequently, the protocol was amended so newly enrolled patients received an ISD: 200 mg once daily in patients with baseline body weight < 77 kg or baseline platelet count < 150,000/µL, and 300 mg once daily in all other patients. Efficacy and safety outcomes were assessed by starting dose. RESULTS: Overall, 475 (64.8%) patients were assigned to an FSD (niraparib, n = 317; placebo, n = 158) and 258 (35.2%) were assigned to an ISD (niraparib, n = 170; placebo, n = 88). Efficacy in patients who received FSD or ISD was similar for the overall (FSD hazard ratio [HR], 0.59 [95% CI, 0.46-0.76] vs. ISD HR, 0.69 [95% CI, 0.48-0.98]) and the homologous recombination-deficient (FSD HR, 0.44 [95% CI, 0.30-0.64] vs. ISD HR, 0.39 [95% CI, 0.22-0.72]) populations. In patients with low body weight/platelet count, rates of grades ≥3 and 4 hematologic treatment-emergent adverse events, dose interruptions, and dose reductions were lower for those who received ISD than for those who received FSD. CONCLUSIONS: In PRIMA, similar dose intensity, similar efficacy, and improved safety were observed with the ISD compared with the FSD regimen.

Neoadjuvant Talazoparib in Patients With Germline BRCA1/2 Mutation-Positive, Early-Stage Triple-Negative Breast Cancer: Results of a Phase II Study.

BACKGROUND: The undetermined efficacy of the current standard-of-care neoadjuvant treatment, anthracycline/platinum-based chemotherapy, in patients with early-stage triple-negative breast cancer (TNBC) and germline BRCA mutations emphasizes the need for biomarker-targeted treatment, such as poly(ADP-ribose) polymerase inhibitors, in this setting. This phase II, single-arm, open-label study evaluated the efficacy and safety of neoadjuvant talazoparib in patients with germline BRCA1/2-mutated early-stage TNBC. PATIENTS AND METHODS: Patients with germline BRCA1/2-mutated early-stage TNBC received talazoparib 1 mg once daily for 24 weeks (0.75 mg for moderate renal impairment) followed by surgery. The primary endpoint was pathologic complete response (pCR) by independent central review (ICR). Secondary endpoints included residual cancer burden (RCB) by ICR. Safety and tolerability of talazoparib and patient-reported outcomes were assessed. RESULTS: Of 61 patients, 48 received ≥80% talazoparib doses, underwent surgery, and were assessed for pCR or progressed before pCR assessment and considered nonresponders. pCR rate was 45.8% (95% confidence interval [CI], 32.0%-60.6%) and 49.2% (95% CI, 36.7%-61.6%) in the evaluable and intent-to-treat (ITT) population, respectively. RCB 0/I rate was 45.8% (95% CI, 29.4%-63.2%) and 50.8% (95% CI, 35.5%-66.0%) in the evaluable and ITT population, respectively. Treatment-related adverse events (TRAE) were reported in 58 (95.1%) patients. Most common grade 3 and 4 TRAEs were anemia (39.3%) and neutropenia (9.8%). There was no clinically meaningful detriment in quality of life. No deaths occurred during the reporting period; 2 deaths due to progressive disease occurred during long-term follow-up (>400 days after first dose). CONCLUSIONS: Neoadjuvant talazoparib monotherapy was active despite pCR rates not meeting the prespecified threshold; these rates were comparable to those observed with combination anthracycline- and taxane-based chemotherapy regimens. Talazoparib was generally well tolerated. CLINICALTRIALS.GOV IDENTIFIER: NCT03499353.

Niraparib and dostarlimab for the treatment of recurrent platinum-resistant ovarian cancer: results of a Phase II study (MOONSTONE/GOG-3032).

OBJECTIVE: This study assessed the efficacy, safety, and health-related quality of life (HRQoL) of the treatment regimen of dostarlimab, a programmed death-1 inhibitor, combined with niraparib, a poly (ADP-ribose) polymerase inhibitor, in patients with BRCA wild type (BRCAwt) recurrent platinum-resistant ovarian cancer (PROC) who had previously received bevacizumab treatment. METHODS: This Phase II, open-label, single-arm, multicenter study, conducted in the USA, enrolled patients with recurrent PROC to receive niraparib and dostarlimab until disease progression or unacceptable toxicity (up to 3 years). A preplanned interim futility analysis was performed after the first 41 patients had undergone ≥1 radiographic evaluation (approximately 9 weeks from the first treatment). RESULTS: The prespecified interim futility criterion was met and the study was therefore terminated. For the 41 patients assessed, the objective response rate (ORR) was 7.3% (95% confidence interval: 1.5-19.9); no patients achieved a complete response, 3 patients (7.3%) achieved a partial response (duration of response; 3.0, 3.8, and 9.2 months, respectively), and 9 patients (22.0%) had stable disease. In total, 39 patients (95.1%) experienced a treatment-related adverse event, but no new safety issues were observed. HRQoL, assessed using FOSI, or Functional Assessment of Cancer Therapy - Ovarian Symptom Index scores, worsened over time compared with baseline scores. CONCLUSIONS: The study was terminated due to the observed ORR at the interim futility analysis. This highlights a need for effective therapies in treating patients with recurrent BRCAwt PROC.

Poly(adenosine diphosphate-ribose) polymerase inhibitor combinations in first-line metastatic castrate-resistant prostate cancer setting: a systematic review and meta-analysis.

OBJECTIVES: To compare radiographic progression-free survival (rPFS), overall survival (OS), and treatment-emergent adverse events (TEAEs) among patients with metastatic castrate-resistant prostate cancer (mCRPC) receiving a combination of first-line poly(adenosine diphosphate-ribose) polymerase inhibitors (PARPi) plus androgen receptor axis-targeted agents (ARAT) vs placebo/ARAT. MATERIALS AND METHODS: We conducted a systematic review/meta-analysis of all published Phase III randomised controlled trials using EMBASE, MEDLINE, and Cochrane (inception until 6 June 2023). Published full-text manuscripts and conference abstracts were inclusion eligible. Study selection/data extraction were independently performed by two authors. The Cochrane Risk-of-Bias 2 Tool was used, and certainty of evidence assessed using the Grading of Recommendations, Assessment, Development, and Evaluations framework. Pooled hazard ratios (HRs) and relative risks, with corresponding confidence intervals (CIs), were generated using random-effects models. RESULTS: Three trials were identified: PROpel, MAGNITUDE, and TALAPRO-2. Compared to placebo/ARAT, the PARPi/ARAT combination was associated with a 35% rPFS improvement in the overall cohort (HR 0.65, 95% CI 0.56-0.76), with 68%, 45%, and 26% improvements in the BReast CAncer gene 1/gene 2 (BRCA1/2)-mutated (BRCA1/2m; P < 0.001), homologous recombination repair-mutated (HRRm; P < 0.001), and non-HRRm cohorts (P = 0.003), respectively. OS data maturity ranged from 31% to 48%, with overall cohort OS data unavailable from MAGNITUDE. The PROpel/TALAPRO-2 pooled analysis demonstrated a 16% OS improvement in the overall cohort (HR 0.84, 95 CI 0.72-0.98; P = 0.02). OS in the HRRm (HR 0.76, 95% CI 0.61-0.95) and the BRCA1/2m cohorts (HR 0.53, 95% CI 0.18-1.56) were improved, with a higher effect magnitude compared to the overall cohort. This combination was associated with a 45% relative risk increase in Grade ≥3 TEAEs, including 6.22-fold for Grade ≥3 anaemia (31.9% vs 4.9%). CONCLUSIONS: The addition of PARPi to ARAT in the first-line mCRPC setting is associated with rPFS benefits across subgroups, with the greatest magnitude of benefit in BRCA1/2m patients. OS benefits remain inconsistent irrespective of HRRm status, with significant increases in Grade ≥3 TEAEs, particularly anaemia. Currently, we suggest this combined approach be selectively offered to HRRm patients, preferentially BRCA1/2m.

ISO 15189 is a sufficient instrument to guarantee high-quality manufacture of laboratory developed tests for in-house-use conform requirements of the European In-Vitro-Diagnostics Regulation.

The EU In-Vitro Diagnostic Device Regulation (IVDR) aims for transparent risk-and purpose-based validation of diagnostic devices, traceability of results to uniquely identified devices, and post-market surveillance. The IVDR regulates design, manufacture and putting into use of devices, but not medical services using these devices. In the absence of suitable commercial devices, the laboratory can resort to laboratory-developed tests (LDT) for in-house use. Documentary obligations (IVDR Art 5.5), the performance and safety specifications of ANNEX I, and development and manufacture under an ISO 15189-equivalent quality system apply. LDTs serve specific clinical needs, often for low volume niche applications, or correspond to the translational phase of new tests and treatments, often extremely relevant for patient care. As some commercial tests may disappear with the IVDR roll-out, many will require urgent LDT replacement. The workload will also depend on which modifications to commercial tests turns them into an LDT, and on how national legislators and competent authorities (CA) will handle new competences and responsibilities. We discuss appropriate interpretation of ISO 15189 to cover IVDR requirements. Selected cases illustrate LDT implementation covering medical needs with commensurate management of risk emanating from intended use and/or design of devices. Unintended collateral damage of the IVDR comprises loss of non-profitable niche applications, increases of costs and wasted resources, and migration of innovative research to more cost-efficient environments. Taking into account local specifics, the legislative framework should reduce the burden on and associated opportunity costs for the health care system, by making diligent use of existing frameworks.

Pharmacologic induction of innate immune signaling directly drives homologous recombination deficiency.

Poly(ADP ribose) polymerase inhibitors (PARPi) have efficacy in triple negative breast (TNBC) and ovarian cancers (OCs) harboring BRCA mutations, generating homologous recombination deficiencies (HRDs). DNA methyltransferase inhibitors (DNMTi) increase PARP trapping and reprogram the DNA damage response to generate HRD, sensitizing BRCA-proficient cancers to PARPi. We now define the mechanisms through which HRD is induced in BRCA-proficient TNBC and OC. DNMTi in combination with PARPi up-regulate broad innate immune and inflammasome-like signaling events, driven in part by stimulator of interferon genes (STING), to unexpectedly directly generate HRD. This inverse relationship between inflammation and DNA repair is critical, not only for the induced phenotype, but also appears as a widespread occurrence in The Cancer Genome Atlas datasets and cancer subtypes. These discerned interactions between inflammation signaling and DNA repair mechanisms now elucidate how epigenetic therapy enhances PARPi efficacy in the setting of BRCA-proficient cancer. This paradigm will be tested in a phase I/II TNBC clinical trial.

RAD51D Secondary Mutation-Mediated Resistance to PARP-Inhibitor-Based Therapy in HGSOC.

Ovarian cancer is the leading cause of gynecologic cancer-related death, and PARP inhibitors (PARPis) are becoming a promising treatment option, as demonstrated by recent clinical trials. After PARPi exposure, somatic reversion mutations in the homologous recombination genes may be a mechanism of PARPi resistance in ovarian carcinoma. We present an ovarian cancer case of a 61-year-old woman, who underwent routine tumor reduction surgery followed by platinum and PARPis. She demonstrated a good response to PARPis for 15 months before recurrence and secondary tumor reduction surgery. However, post-surgery platinum and PARPi treatment only kept the disease stable for 5 months. A potential molecular mechanism for PARPi resistance was investigated using next-generation sequencing, immunohistochemical (IHC) staining, and other functional assays. A germline RAD51D loss-of-function mutation was found in the reported case (LRG_516t1:c.270_271dup p1:p.(Lys91fs*13)). Subsequently, a secondary mutation (LRG_516t1:c.271_282 del) was identified in the same locus of the germline duplication in the post-progression biopsies and ctDNA. The IHC staining supported low expression of RAD51D in the initial tumor tissue, but the expression was restored after the correction of the open reading frame by the secondary mutation. The in vitro results supported that the loss-of-function mutation of RAD51D was the basis for the initial response to the platinum and PARPi therapy, while the newly acquired reversion mutation could be attributed to the observed PARPi resistance. An acquired mutation can reverse a loss-of-function change in RAD51D and can result in PARPi resistance in a hereditary ovarian cancer patient. Liquid biopsy could be considered for longitudinal monitoring in ovarian patients under PARPi-based therapy, which can identify acquired resistant mutations earlier and facilitate precision management.

[Chinese expert consensus on drug interaction management of poly ADP-ribose polymerase inhibitors].

Poly ADP-ribose polymerase inhibitors (PARPi), which approved in recent years, are recommended for ovarian cancer, breast cancer, pancreatic cancer, prostate cancer and other cancers by The National Comprehensive Cancer Network (NCCN) and Chinese Society of Clinical Oncology (CSCO) guidelines. Because most of PARPi are metabolized by cytochrome P450 enzyme system, there are extensive interactions with other drugs commonly used in cancer patients. By setting up a consensus working group including pharmaceutical experts, clinical experts and methodology experts, this paper forms a consensus according to the following steps: determine clinical problems, data retrieval and evaluation, Delphi method to form recommendations, finally formation expert opinion on PARPi interaction management. This paper will provide practical reference for clinical medical staff.

JASPER: Phase 2 trial of first-line niraparib plus pembrolizumab in patients with advanced non-small cell lung cancer.

BACKGROUND: Poly(ADP-ribose) polymerase (PARP) inhibitors may synergize with programmed cell death receptor-1 (PD-1) inhibitors to enhance adaptive and innate antitumor immune responses. In the phase 2 JASPER study (NCT04475939), the PARP inhibitor niraparib was evaluated in combination with the PD-1 inhibitor pembrolizumab in patients with metastatic and/or locally advanced non-small cell lung cancer (NSCLC). METHODS: Patients whose tumors had programmed cell death ligand 1 (PD-L1) tumor proportion scores (TPS) ≥50% (cohort 1) or 1%-49% (cohort 2) received first-line niraparib (200 mg once daily) plus pembrolizumab (200 mg every 3 weeks). The primary end point was investigator-assessed objective response rate (ORR). Secondary end points included duration of response (DoR), progression-free survival (PFS), overall survival (OS), safety, and pharmacokinetics. RESULTS: Thirty-eight patients were enrolled in cohorts 1 and 2. In cohort 1, ORR (95% confidence interval [CI]) was 56.3% (9 of 16 patients; 29.9%-80.2%); 2 of 16 patients had complete responses and 7 of 16 had partial responses (PRs). In cohort 2, ORR was 20.0% (5.7%-43.7%) with 4 of 20 PRs. In cohorts 1 and 2, the median DoR was 19.7 months (95% CI, 4.2 months to not estimable [NE]) and 9.4 months (95% CI, 4.2 months to NE), the median PFS was 8.4 months (95% CI, 3.9-22.1 months) and 4.2 months (95% CI, 2.0-6.2 months), and the median OS was NE (95% CI, 6.0 months to NE) and 7.7 months (95% CI, 4.0-12.5 months), respectively. Grade ≥3 treatment-emergent adverse events occurred in 88.2% and 85.7% of patients in cohorts 1 and 2, respectively. Safety was consistent with known profiles of single-agent niraparib and pembrolizumab. CONCLUSIONS: Niraparib plus pembrolizumab showed clinical activity in patients with advanced and/or metastatic NSCLC. LAY SUMMARY: The JASPER clinical trial studied a new combination treatment for advanced or metastatic non-small cell lung cancer (NSCLC). Pembrolizumab, a drug approved for NSCLC, was given with niraparib. Previous research showed that these 2 drugs together might work better than either drug alone. This study found that more than half of patients with high levels of a tumor marker responded to the combination, and one-fifth of patients with lower levels of the marker responded. The types of side effects from the combination were similar to side effects from both drugs alone. These results support more research on this combination.

Homologous Recombination Deficiency: Concepts, Definitions, and Assays.

BACKGROUND: Homologous recombination deficiency (HRD) is a phenotype that is characterized by the inability of a cell to effectively repair DNA double-strand breaks using the homologous recombination repair (HRR) pathway. Loss-of-function genes involved in this pathway can sensitize tumors to poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitors and platinum-based chemotherapy, which target the destruction of cancer cells by working in concert with HRD through synthetic lethality. However, to identify patients with these tumors, it is vital to understand how to best measure homologous repair (HR) status and to characterize the level of alignment in these measurements across different diagnostic platforms. A key current challenge is that there is no standardized method to define, measure, and report HR status using diagnostics in the clinical setting. METHODS: Friends of Cancer Research convened a consortium of project partners from key healthcare sectors to address concerns about the lack of consistency in the way HRD is defined and methods for measuring HR status. RESULTS: This publication provides findings from the group's discussions that identified opportunities to align the definition of HRD and the parameters that contribute to the determination of HR status. The consortium proposed recommendations and best practices to benefit the broader cancer community. CONCLUSION: Overall, this publication provides additional perspectives for scientist, physician, laboratory, and patient communities to contextualize the definition of HRD and various platforms that are used to measure HRD in tumors.

Real-world patient-reported outcomes and physician satisfaction with poly (ADP-ribose) polymerase inhibitors versus chemotherapy in patients with germline BRCA1/2-mutated human epidermal growth factor receptor 2-negative advanced breast cancer from the United States, Europe, and Israel.

BACKGROUND: In clinical trials, poly (ADP-ribose) polymerase inhibitors (PARPi) versus chemotherapy resulted in significantly improved progression-free survival, manageable adverse event profiles, and favorable patient-reported outcomes (PROs) in patients with human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) and germline BRCA1/2 mutations (gBRCA1/2mut). The objective of this study was to evaluate PROs and physician satisfaction with treatment in patients with gBRCA1/2mut HER2- ABC receiving PARPi or physician's choice of chemotherapy in a multi-country, real-world setting. METHODS: This retrospective analysis used data from the Adelphi Real World ABC Disease Specific Programmes in the United States, European Union, and Israel. PROs were assessed at a single timepoint using the EuroQol 5-Dimensions 5-Level (EQ-5D-5L) scale, Cancer Therapy Satisfaction Questionnaire (CTSQ), and European Organization for Research and Treatment of Cancer Quality-of-Life Questionnaire Core 30 (EORTC QLQ-C30) and the breast cancer-specific module (QLQ-BR23). Baseline PROs were not assessed. Physician satisfaction with treatment scores was dichotomized to a 0/1 variable (0 = very dissatisfied/dissatisfied/moderately satisfied; 1 = satisfied/very satisfied). Scores were compared using inverse-probability-weighted regression adjustment, controlling for multiple confounding factors. RESULTS: The study included 96 patients (PARPi, n = 38; platinum/non-platinum-based chemotherapy, n = 58). Patients receiving PARPi versus chemotherapy reported significantly better scores on the EQ-5D-5L Health Utility Index. On the EORTC QLQ-C30 functional scales, patients receiving PARPi reported significantly better scores (mean ± SE) for physical functioning (80.0 ± 2.4 vs 71.9 ± 3.4; p < 0.05) and social functioning (82.0 ± 6.2 vs 63.6 ± 3.7; p < 0.05) and, on the symptom scales, reported significantly better scores for constipation (1.9 ± 1.8 vs 18.7 ± 3.2; p < 0.001), breast symptoms (0.4 ± 3.9 vs 13.3 ± 2.6; p < 0.01), arm symptoms (2.6 ± 1.3 vs 11.4 ± 2.4; p = 0.001), and systemic therapy side effects (13.5 ± 1.8 vs 29.4 ± 2.3; p < 0.001). In contrast, patients receiving chemotherapy scored significantly better on the nausea/vomiting scale (18.3 ± 2.8 vs 34.5 ± 5.1; p < 0.01). Patients receiving PARPi reported numerically better satisfaction scores on the CTSQ scales. Physicians were more likely to be satisfied/very satisfied with PARPi versus chemotherapy (95.4% ± 7.3% vs 40.8% ± 6.2%; p < 0.001). CONCLUSIONS: The PRO findings in this real-world population of patients with gBRCA1/2mut HER2- ABC complement those from the pivotal clinical trials, providing further support for treatment with PARPi in these patients.

Bevacizumab versus PARP-inhibitors in women with newly diagnosed ovarian cancer: a network meta-analysis.

BACKGROUND: In women with newly diagnosed ovarian cancer, bevacizumab and poly (ADP-ribose) polymerase inhibitors (PARPi) exhibit improved progression-free survival (PFS) when administered concurrent with chemotherapy and/or maintenance therapy, but no study has directly compared their effects. Therefore, this study aimed to compare the efficacy and safety of bevacizumab and PARPi in women with newly diagnosed ovarian cancer using a network meta-analysis. METHODS: PubMed, Medline, and Embase databases were searched, and five randomized trials assessing PFS in women with newly diagnosed ovarian cancer treated with either bevacizumab, PARPi, or placebo or no additional agent (controls) were identified. PFS was compared in the overall population with ovarian cancer, women with a BRCA1/2 mutation (BRCAm) and women with homologous-recombination deficiency (HRD). Adverse events (grade ≥ 3) were compared in all populations of the included studies. RESULTS: PARPi improved PFS significantly more than bevacizumab in women with a BRCAm (HR 0.47; 95% CI 0.36-0.60) and with HRD (HR 0.66; 95% CI 0.50-0.87). However, in the overall population with ovarian cancer, no significant difference in PFS was observed between women treated with PARPi and those treated with bevacizumab. PARPi exhibited the highest surface under the cumulative ranking probabilities value as the most effective treatment for PFS (PARPi vs. bevacizumab: 98% vs. 52% in the overall population with ovarian cancer; 100% vs. 50% in women with BRCAm; 100% vs. 50% in women with HRD). For adverse events, the risk of all treatments was similar. However, PARPi had a higher adverse risk than the control group (relative risk 2.14; 95% CI 1.40-3.26). CONCLUSIONS: In women with newly diagnosed ovarian cancer, PARPi might be more effective in terms of PFS compared to bevacizumab. The risk of serious adverse events was similar for PARPi and bevacizumab.

Homologous recombination deficiency (HRD) signature-3 in ovarian and uterine carcinosarcomas correlates with preclinical sensitivity to Olaparib, a poly (adenosine diphosphate [ADP]- ribose) polymerase (PARP) inhibitor.

OBJECTIVES: Carcinosarcoma (CS) of the ovary and uterus are highly aggressive malignancies associated with poor survival. Poly(ADP-ribose)-polymerase inhibitors (PARPi) are targeted agents impairing DNA repair via homologous-recombination-deficiency (HRD) mechanisms. We used whole-exome-sequencing (WES) data from a cohort of fresh tumor samples of ovarian (OCS) and uterine carcinosarcoma (UCS), primary cell lines and xenografts to investigate the role for olaparib in CSs. METHODS: WES data from 73 CS samples (48 UCS and 25 OCS) were analyzed for HRD signatures. Olaparib activity was evaluated using cell-viability, cell-cycle, apoptosis and cytotoxicity assays against primary CS cell lines. Olaparib antitumor activity was tested in vivo against HRD CS xenografts. RESULTS: Signature-3 (i.e. HRD-related signature) was identified in 60% of OCS (15 of 25) vs 25% of UCS (12 of 48) (p = 0.005). CS cell lines harboring Signature-3/HRD (3 OCS/1 UCS) were significantly more sensitive to olaparib when compared to HRP cell lines (5 UCS/1 OCS) [mean IC50 ± SEM = 2.94 µM ± 0.07 vs mean ± SEM = 23.3 µM ± 0.09, (p = 0.02), respectively]. PARPi suppressed CS cell growth through cell cycle arrest in the G2/M phase and caused more apoptosis in HRD vs HRP primary tumors (p < 0.0001). In vivo, olaparib significantly impaired HRD CS xenografts tumor growth (p = 0.0008) and increased overall animal survival (p < 0.0001). CONCLUSIONS: OCS and UCS cell lines harboring HRD signature-3 were significantly more sensitive to olaparib in vitro and in vivo when compared to HRP CS. Clinical studies with PARPi in CS patients with a dominant signature 3 (HRD-related) are warranted.

Assessing cognitive toxicity in early phase trials - What are we missing?

OBJECTIVES: Novel therapies, such as, small protein molecule inhibitors and immunotherapies are first tested clinically in Phase I trials. Moving on to later phase trials and ultimately standard practice. A key aim of these early clinical trials is to define a toxicity profile; however, the emphasis is often on safety. The concern is cognitive toxicity is poorly studied in this context and may be under-reported. The aim of this review is to map evidence of cognitive assessment, toxicity, and confounding factors within reports from Phase I trials and consider putative mechanisms of impairment aligned with mechanisms of novel therapies. METHODS: A scoping review methodology was applied to the search of databases, including Embase, MEDLINE, Clinicaltrials.gov. A [keyword search was conducted, results screened for duplication then inclusion/exclusion criteria applied. Articles were further screened for relevance; data organised into categories and charted in a tabular format]. Evidence was collated and summarised into a narrative synthesis. RESULTS: Despite the availability of robust ways to assess cognitive function, these are not routinely included in the conduct of early clinical trials. Reports of cognitive toxicity in early Phase I trials are limited and available evidence on this shows that a proportion of patients experience impaired cognitive function over the course of participating in a Phase I trial. Links are identified between the targeted action of some novel therapies and putative mechanisms of cognitive impairment. CONCLUSION: The review provides rationale for research investigating cognitive function in this context. A study exploring the cognitive function of patients on Phase I trials and the feasibility of formally assessing this within early clinical trials is currently underway at the Royal Marsden.