The poly (ADP ribose) polymerase inhibitor niraparib: Management of toxicities.

Niraparib is an oral poly(ADP ribose) polymerase (PARP) inhibitor that is currently approved by the United States Food and Drug Administration (US FDA) as well as recently approved by the European Medicines Agency (EMA) for the maintenance treatment of women with recurrent ovarian cancer who are in complete or partial response to platinum-based chemotherapy. The mechanisms of action of niraparib include inhibition of PARP enzymatic activity as well as increased formation of PARP-DNA complexes through "trapping" the PARP enzyme on damaged DNA. Phase I and III studies have demonstrated activity and benefit of niraparib in both BRCA mutated (BRCAm) and BRCA wild-type (BRCAwt) cancers. Phase I testing of niraparib established the maximally tolerated dose of 300mg by mouth (PO) daily, and the phase 3 ENGOT-OV16/NOVA study demonstrated the benefit of niraparib maintenance therapy compared to placebo after completion of and response to platinum-based chemotherapy in both BRCAm and BRCAwt ovarian cancer patient populations. Toxicities seen with niraparib include hematologic, gastrointestinal, fatigue, and cardiovascular. Hematologic toxicities include thrombocytopenia, anemia, neutropenia and leukopenia; upfront dose modification to 200mg niraparib for patients with baseline weight of ≤77kg and/or baseline platelets of ≤150,000K/uL should be considered to avoid significant hematologic toxicity, especially thrombocytopenia, based on recent analyses of the ENGOT-OV16/NOVA study. Cardiovascular toxicities include hypertension, tachycardia, as well as palpitations, and patients should be monitored for hypertension. PARP inhibitors have been associated with low risks of acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS), and the overall risk of AML and MDS is 0.9% of all patients treated with niraparib. Niraparib testing is ongoing in newly diagnosed ovarian cancer patients as maintenance therapy following completion of platinum-based chemotherapy, in BRCAwt cancers as treatment, as well as in combinations with other biologic drugs such as immunotherapy and anti-angiogenic agents.

A phase II study of combination chemotherapy in early relapsed epithelial ovarian cancer using gemcitabine and pegylated liposomal doxorubicin.

OBJECTIVE: Treatment of epithelial ovarian cancer patients relapsing with a short treatment-free interval (TFI) after prior chemotherapy is unsatisfactory. This phase II trial evaluated the activity and feasibility of pegylated liposomal doxorubicin (PLD) plus gemcitabine in this setting. METHODS: Patients who had received prior platinum and paclitaxel with a TFI 0-12 months received PLD 25 mg/m(2)day 1 plus gemcitabine 800 mg/m(2)day 1, 8 every 21 days. Gemcitabine was dose escalated to 1000 mg/m(2)day 1, 8 from course 2 in the absence of grade 3/4 toxicity. The primary endpoint was progression-free survival (PFS). Patients were stratified according to response to primary chemotherapy. RESULTS: Seventy-nine patients (n=26 with CR on prior chemotherapy and TFI 6-12 months; n=20 with CR and TFI 0-6 months; n=33 with PR/SD and TFI 0-12 months) were enrolled. The median age was 59 years (range 31-77 years), and 33 patients had received ≥ 2 prior treatments. A median of five courses was delivered per patient (total 389 courses). Gemcitabine was dose escalated in 124 courses and reduced in 105 courses. No PLD dose reductions occurred. Grade 3/4 toxicities were febrile neutropenia (n=4), PPE (n=2), and mucositis (n=2). One toxic death occurred (pneumonitis/alveolitis). Responses were complete in 5.1%, partial in 27.9%, and stable disease in 55.7%. Median OS and PFS were 12.5 and 6.4 months, respectively. CONCLUSIONS: The PLD-gemcitabine combination is an effective and well-tolerated salvage treatment for relapsed epithelial ovarian cancer and is a valid candidate for evaluation in a phase III trial.

MILO/ENGOT-ov11: Binimetinib Versus Physician's Choice Chemotherapy in Recurrent or Persistent Low-Grade Serous Carcinomas of the Ovary, Fallopian Tube, or Primary Peritoneum.

PURPOSE: Low-grade serous ovarian carcinomas (LGSOCs) have historically low chemotherapy responses. Alterations affecting the MAPK pathway, most commonly KRAS/BRAF, are present in 30%-60% of LGSOCs. The purpose of this study was to evaluate binimetinib, a potent MEK1/2 inhibitor with demonstrated activity across multiple cancers, in LGSOC. METHODS: This was a 2:1 randomized study of binimetinib (45 mg twice daily) versus physician's choice chemotherapy (PCC). Eligible patients had recurrent measurable LGSOC after ≥ 1 prior platinum-based chemotherapy but ≤ 3 prior chemotherapy lines. The primary end point was progression-free survival (PFS) by blinded independent central review (BICR); additional assessments included overall survival (OS), overall response rate (ORR), duration of response (DOR), clinical-benefit rate, biomarkers, and safety. RESULTS: A total of 303 patients were randomly assigned to an arm of the study at the time of interim analysis (January 20, 2016). Median PFS by BICR was 9.1 months (95% CI, 7.3 to 11.3) for binimetinib and 10.6 months (95% CI, 9.2 to 14.5) for PCC (hazard ratio,1.21; 95%CI, 0.79 to 1.86), resulting in early study closure according to a prespecified futility boundary after 341 patients had enrolled. Secondary efficacy end points were similar in the two groups: ORR 16% (complete response [CR]/partial responses[PRs], 32) versus 13% (CR/PRs, 13); median DOR, 8.1 months (range, 0.03 to ≥ 12.0 months) versus 6.7 months (0.03 to ≥ 9.7 months); and median OS, 25.3 versus 20.8 months for binimetinib and PCC, respectively. Safety results were consistent with the known safety profile of binimetinib; the most common grade ≥ 3 event was increased blood creatine kinase level (26%). Post hoc analysis suggests a possible association between KRAS mutation and response to binimetinib. Results from an updated analysis (n = 341; January 2019) were consistent. CONCLUSION: Although the MEK Inhibitor in Low-Grade Serous Ovarian Cancer Study did not meet its primary end point, binimetinib showed activity in LGSOC across the efficacy end points evaluated. A higher response to chemotherapy than expected was observed and KRAS mutation might predict response to binimetinib.

ENGOT-ov-6/TRINOVA-2: Randomised, double-blind, phase 3 study of pegylated liposomal doxorubicin plus trebananib or placebo in women with recurrent partially platinum-sensitive or resistant ovarian cancer.

AIMS: Trebananib, a peptide-Fc fusion protein, inhibits angiogenesis by inhibiting binding of angiopoietin-1/2 to the receptor tyrosine kinase Tie2. This randomised, double-blind, placebo-controlled phase 3 study evaluated whether trebananib plus pegylated liposomal doxorubicin (PLD) improved progression-free survival (PFS) in patients with recurrent epithelial ovarian cancer. METHODS: Women with recurrent ovarian cancer (platinum-free interval ≤12 months) were randomised to intravenous PLD 50 mg/m2 once every 4 weeks plus weekly intravenous trebananib 15 mg/kg or placebo. PFS was the primary end-point; key secondary end-points were objective response rate (ORR) and duration of response (DOR). Owing to PLD shortages, enrolment was paused for 13 months; the study was subsequently truncated. RESULTS: Two hundred twenty-three patients were enrolled. Median PFS was 7.6 months (95% CI, 7.2-9.0) in the trebananib arm and 7.2 months (95% CI, 4.8-8.2) in the placebo arm, with a hazard ratio of 0.92 (95% CI, 0.68-1.24). However, because the proportional hazards assumption was not fulfilled, the standard Cox model did not provide a reliable estimate of the hazard ratio. ORR in the trebananib arm was 46% versus 21% in the placebo arm (odds ratio, 3.43; 95% CI, 1.78-6.64). Median DOR was improved (trebananib, 7.4 months [95% CI, 5.7-7.6]; placebo, 3.9 months [95% CI, 2.3-6.5]). Adverse events with a greater incidence in the trebananib arm included localised oedema (61% versus 32%), ascites (29% versus 9%) and vomiting (45% versus 33%). CONCLUSIONS: Trebananib demonstrated anticancer activity in this phase 3 study, indicated by improved ORR and DOR. Median PFS was not improved. No new safety signals were identified. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01281254.

Patient-reported outcome results from the open-label phase III AURELIA trial evaluating bevacizumab-containing therapy for platinum-resistant ovarian cancer.

PURPOSE: To determine the effects of bevacizumab on patient-reported outcomes (PROs; secondary end point) in the AURELIA trial. PATIENTS AND METHODS: Patients with platinum-resistant ovarian cancer were randomly assigned to chemotherapy alone (CT) or with bevacizumab (BEV-CT). PROs were assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Ovarian Cancer Module 28 (EORTC QLQ-OV28) and Functional Assessment of Cancer Therapy-Ovarian Cancer symptom index (FOSI) at baseline and every two or three cycles (8/9 weeks) until disease progression. The primary PRO hypothesis was that more patients receiving BEV-CT than CT would achieve at least a 15% (≥ 15-point) absolute improvement on the QLQ-OV28 abdominal/GI symptom subscale (items 31-36) at week 8/9. Patients with missing week 8/9 questionnaires were included as unimproved. Questionnaires from all assessments until disease progression were analyzed using mixed-model repeated-measures (MMRM) analysis. Sensitivity analyses were used to determine the effects of differing assumptions and methods for missing data. RESULTS: Baseline questionnaires were available from 89% of 361 randomly assigned patients. More BEV-CT than CT patients achieved a ≥ 15% improvement in abdominal/GI symptoms at week 8/9 (primary PRO end point, 21.9% v 9.3%; difference, 12.7%; 95% CI, 4.4 to 20.9; P = .002). MMRM analysis covering all time points also favored BEV-CT (difference, 6.4 points; 95% CI, 1.3 to 11.6; P = .015). More BEV-CT than CT patients achieved ≥ 15% improvement in FOSI at week 8/9 (12.2% v 3.1%; difference, 9.0%; 95% CI, 2.9% to 15.2%; P = .003). Sensitivity analyses gave similar results and conclusions. CONCLUSION: Bevacizumab increased the proportion of patients achieving a 15% improvement in patient-reported abdominal/GI symptoms during chemotherapy for platinum-resistant ovarian cancer.

Bevacizumab combined with chemotherapy for platinum-resistant recurrent ovarian cancer: The AURELIA open-label randomized phase III trial.

PURPOSE: In platinum-resistant ovarian cancer (OC), single-agent chemotherapy is standard. Bevacizumab is active alone and in combination. AURELIA is the first randomized phase III trial to our knowledge combining bevacizumab with chemotherapy in platinum-resistant OC. PATIENTS AND METHODS: Eligible patients had measurable/assessable OC that had progressed < 6 months after completing platinum-based therapy. Patients with refractory disease, history of bowel obstruction, or > two prior anticancer regimens were ineligible. After investigators selected chemotherapy (pegylated liposomal doxorubicin, weekly paclitaxel, or topotecan), patients were randomly assigned to single-agent chemotherapy alone or with bevacizumab (10 mg/kg every 2 weeks or 15 mg/kg every 3 weeks) until progression, unacceptable toxicity, or consent withdrawal. Crossover to single-agent bevacizumab was permitted after progression with chemotherapy alone. The primary end point was progression-free survival (PFS) by RECIST. Secondary end points included objective response rate (ORR), overall survival (OS), safety, and patient-reported outcomes. RESULTS: The PFS hazard ratio (HR) after PFS events in 301 of 361 patients was 0.48 (95% CI, 0.38 to 0.60; unstratified log-rank P < .001). Median PFS was 3.4 months with chemotherapy alone versus 6.7 months with bevacizumab-containing therapy. RECIST ORR was 11.8% versus 27.3%, respectively (P = .001). The OS HR was 0.85 (95% CI, 0.66 to 1.08; P < .174; median OS, 13.3 v 16.6 months, respectively). Grade ≥ 2 hypertension and proteinuria were more common with bevacizumab. GI perforation occurred in 2.2% of bevacizumab-treated patients. CONCLUSION: Adding bevacizumab to chemotherapy statistically significantly improved PFS and ORR; the OS trend was not significant. No new safety signals were observed.

Early decline in cancer antigen 125 as a surrogate for progression-free survival in recurrent ovarian cancer.

We used data from 886 patients from the CAELYX in Platinum Sensitive Ovarian Patients (CALYPSO) trial, recruited between April 2005 and September 2007, to examine the role of early decline in cancer antigen 125 (CA125) and early tumor response as prognostic factors and surrogates for superiority of treatment with carboplatin-pegylated liposomal doxorubicin (CPLD) compared with carboplatin-paclitaxel (CP) in a landmark analysis. Progression-free survival (PFS) was estimated by Kaplan-Meier analyses. We used univariate and multivariable Cox proportional hazards analyses to assess early decline and early response as surrogates for CPLD treatment benefit compared with CP. All statistical tests were two-sided. Early decline (defined as rate of CA125 decrease of at least 50% per month) was associated with improved PFS (adjusted hazard ratio [HR] for progression = 0.81, 95% confidence interval [CI] = 0.67 to 0.97, P = .02) but early response (complete or partial responses) was not. CPLD was associated with improved PFS compared with CP (HR = 0.82, 95% CI = 0.69 to 0.96, P = .01). However, fewer CPLD patients had an early decline (161 [37.4%] vs 233 [51.2%], P < .001) or an early response (146 [33.9%] vs 176 [38.7%], P = .14) compared with CP patients. The PFS for CPLD patients did not change statistically significantly after adjustment for early decline (adjusted HR = 0.80, 95% CI = 0.68 to 0.94, P = .007). These findings are opposite to what would be expected if these markers were good surrogates for treatment benefit.