Optimising the treatment of the partially platinum-sensitive relapsed ovarian cancer patient

Efficacy and safety of rucaparib treatment in patients with BRCA-mutated, relapsed ovarian cancer: final results from Study 10

BACKGROUND

Study 10, a four-part Phase 1/2 study, evaluated oral rucaparib monotherapy in patients with advanced solid tumours. Here we report the final efficacy and safety results in heavily pretreated patients with ovarian cancer who received rucaparib in Study 10 Parts 2A and 2B.

METHODS

Parts 2A and 2B (Phase 2 portions) enrolled patients with relapsed, high-grade, platinum-sensitive or platinum-resistant, BRCA-mutated ovarian cancer who had received 2-4 (Part 2A) or 3-4 (Part 2B) prior chemotherapies. Patients received oral rucaparib 600 mg twice daily (starting dose). The primary endpoint was the investigator-assessed objective response rate (ORR) by RECIST v1.1.

RESULTS

Fifty-four patients were enrolled: 42 in Part 2A (all had platinum-sensitive disease) and 12 in Part 2B (4 with platinum-sensitive disease; 8 with platinum-resistant disease). ORR was 59.3% (95% CI 45.0-72.4%). The median time to onset of the most common nonhaematological treatment-emergent adverse events (TEAEs) was typically early (<56 days) and was later for haematological TEAEs (53-84 days). The median duration of grade ≥3 TEAEs was ≤13 days.

CONCLUSIONS

In patients with relapsed, platinum-sensitive or platinum-resistant germline BRCA-mutant high-grade ovarian cancer who had received ≥2 prior chemotherapies, rucaparib had robust antitumour activity with a safety profile consistent with prior reports.

CLINICAL TRIAL REGISTRATION

NCT01482715.

Chemotherapeutic Regimens and Chemotherapy-Free Intervals Influence the Survival of Patients with Recurrent Advanced Epithelial Ovarian Carcinoma: A Retrospective Population-Based Study

We aimed to evaluate factors influencing the outcomes of patients with platinum-sensitive recurrent epithelial ovarian carcinoma (EOC). Patients with advanced-stage EOC, who received debulking surgery and adjuvant chemotherapy for recurrence, were obtained from the National Health Insurance Research database of Taiwan between 2000 and 2013. A total of 1038 patients with recurrent advanced-stage EOC were recruited. The platinum + paclitaxel (PT) group had the best five-year overall survival (OS) compared with the other three groups (p < 0.001). The hazard ratios (HRs) of five-year OS for the platinum + liposomal doxorubicin (PD), topotecan (TOP), and pegylated liposomal doxorubicin (PLD) groups were 1.21 (p = 0.07), 1.35 (p = 0.016), and 1.80 (p < 0.001), respectively, compared with the PT group. The PT group also had lower hazard ratios of five-year OS for patients with platinum therapy-free interval (TFIp) between 6 and 12 months compared with the other three groups (p < 0.0001). However, the HRs of five-year OS did not differ between the PT and PD groups in patients with TFIp >12 months. Patients with TFIp >12 months had lower HRs of five-year OS compared with those with TFIp of 6–12 months, regardless of whether they were treated with platinum-based (p = 0.001) or non-platinum-based (p = 0.003) regimens. Chemotherapeutic regimens and TFIp influenced the outcomes of patients with recurrent EOC. For patients with TFIp of 6–12 months, the PT regimen is the first choice based on their best overall survival result. For patients with TFIp >12 months, either platinum-based or non-platinum regimens could be used because of their similar excellent overall survival.

Rucaparib maintenance treatment for recurrent ovarian carcinoma: the effects of progression-free interval and prior therapies on efficacy and safety in the randomized phase III trial ARIEL3

INTRODUCTION

In ARIEL3 (NCT01968213), the poly(adenosine diphosphate-ribose) polymerase inhibitor rucaparib significantly improved progression-free survival versus placebo regardless of biomarker status when used as maintenance treatment for recurrent ovarian cancer. The aim of the current analyses was to evaluate the efficacy and safety of rucaparib in subgroups based on progression-free interval following penultimate platinum, number of prior chemotherapies, and prior use of bevacizumab.

METHODS

Patients were randomized 2:1 to rucaparib 600 mg twice daily or placebo. Within subgroups, progression-free survival was assessed in prespecified, nested cohorts: BRCA-mutant, homologous recombination deficient (BRCA-mutant or wild-type BRCA/high genomic loss of heterozygosity), and the intent-to-treat population.

RESULTS

In the intent-to-treat population, median investigator-assessed progression-free survival was 8.2 months with rucaparib versus 4.1 months with placebo (n=151 vs n=76; HR 0.33, 95% CI 0.24 to 0.46, p<0.0001) for patients with progression-free interval 6 to ≤12 months, and 13.6 versus 5.6 months (n=224 vs n=113; HR 0.39, 95% CI 0.30 to 0.52, p<0.0001) for those with progression-free interval >12 months. Median progression-free survival was 10.4 versus 5.4 months (n=231 vs n=124; HR 0.42, 95% CI 0.32 to 0.54, p<0.0001) for patients who had received two prior chemotherapies, and 11.1 versus 5.3 months (n=144 vs n=65; HR 0.28, 95% CI 0.19 to 0.41, p<0.0001) for those who had received ≥3 prior chemotherapies. Median progression-free survival was 10.3 versus 5.4 months (n=83 vs n=43; HR 0.42, 95% CI 0.26 to 0.68, p=0.0004) for patients who had received prior bevacizumab, and 10.9 versus 5.4 months (n=292 vs n=146; HR 0.35, 95% CI 0.28 to 0.45, p<0.0001) for those who had not. Across subgroups, median progression-free survival was also significantly longer with rucaparib versus placebo in the BRCA-mutant and homologous recombination deficient cohorts. Safety was consistent across subgroups.

CONCLUSIONS

Rucaparib maintenance treatment significantly improved progression-free survival versus placebo irrespective of progression-free interval following penultimate platinum, number of lines of prior chemotherapy, and previous use of bevacizumab.

Virtual clinical trials identify effective combination therapies in ovarian cancer

A major issue in oncology is the high failure rate of translating preclinical results in successful clinical trials. Using a virtual clinical trial simulations approach, we present a mathematical framework to estimate the added value of combinatorial treatments in ovarian cancer. This approach was applied to identify effective targeted therapies that can be combined with the platinum-taxane regimen and overcome platinum resistance in high-grade serous ovarian cancer. We modeled and evaluated the effectiveness of three drugs that target the main platinum resistance mechanisms, which have shown promising efficacy in vitro, in vivo, and early clinical trials. Our results show that drugs resensitizing chemoresistant cells are superior to those aimed at triggering apoptosis or increasing the bioavailability of platinum. Our results further show that the benefit of using biomarker stratification in clinical trials is dependent on the efficacy of the drug and tumor composition. The mathematical framework presented herein is suitable for systematically testing various drug combinations and clinical trial designs in solid cancers.

Prospective Longitudinal ctDNA Workflow Reveals Clinically Actionable Alterations in Ovarian Cancer

PURPOSE

Circulating tumor DNA (ctDNA) detection is a minimally invasive technique that offers dynamic molecular snapshots of genomic alterations in cancer. Although ctDNA markers can be used for early detection of cancers or for monitoring treatment efficacy, the value of ctDNA in guiding treatment decisions in solid cancers is controversial. Here, we monitored ctDNA to detect clinically actionable alterations during treatment of high-grade serous ovarian cancer, the most common and aggressive form of epithelial ovarian cancer with a 5-year survival rate of 43%.

PATIENTS AND METHODS

We implemented a clinical ctDNA workflow to detect clinically actionable alterations in more than 500 cancer-related genes. We applied the workflow to a prospective cohort consisting of 78 ctDNA samples from 12 patients with high-grade serous ovarian cancer before, during, and after treatment. These longitudinal data sets were analyzed using our open-access ctDNA-tailored bioinformatics analysis pipeline and in-house Translational Oncology Knowledgebase to detect clinically actionable genomic alterations. The alterations were ranked according to the European Society for Medical Oncology scale for clinical actionability of molecular targets.

RESULTS

Our results show good concordance of mutations and copy number alterations in ctDNA and tumor samples, and alterations associated with clinically available drugs were detected in seven patients (58%). Treatment of one chemoresistant patient was changed on the basis of detection of ERBB2 amplification, and this ctDNA-guided decision was followed by significant tumor shrinkage and complete normalization of the cancer antigen 125 tumor marker.

CONCLUSION

Our results demonstrate a proof of concept for using ctDNA to guide clinical decisions. Furthermore, our results show that longitudinal ctDNA samples can be used to identify poor-responding patients after first cycles of chemotherapy. We provide what we believe to be the first comprehensive, open-source ctDNA workflow for detecting clinically actionable alterations in solid cancers.

Treatment of recurrent ovarian cancer with pegylated liposomal doxorubicin: a reappraisal and critical analysis

The vast majority of ovarian cancer relapses on front-line therapy and the optimal treatment of recurrent ovarian cancer remains controversial. This review is based on the relevant published literature indexed in PubMed on pegylated liposomal doxorubicin (PLD), either alone or in combination with other drugs, as one option in relapsed disease. PLD showed an improved pharmacokinetic profile, with a slower plasma clearance and a longer circulation time, compared to other conventional doxorubicin formulations. PLD is considered to have little potential for cardiotoxicity, even at prolonged and high cumulative doses, although there appears to be room for improvement in terms of maximal dose allowed. Notwithstanding, there remain some concerns about cardiac safety, and patient monitoring is generally advocated. No data are available on the possibility to rechallenge PLD treatment in recurrent ovarian cancer, as already known for other drugs. Optimization of treatment regimens with PLD will allow a more rational treatment in advanced ovarian cancers for which few therapeutic options are available.

Combination of weekly topotecan and gemcitabine as a salvage treatment in patients with recurrent ovarian cancer: a phase I study

BACKGROUND

Evaluation of safety of the weekly intravenous gemcitabine/topotecan combination as salvage treatment in patients with recurrent epithelial ovarian cancer.

METHODS

Twenty-four women with histologically-proven relapsed ovarian cancer (ROC) were enrolled in the study. Topotecan (1.75 mg/m2 IV) along with escalated doses of gemcitabine (starting dose 700 mg/m2 with increments of 100 mg/m2) were administered on days 1, 8, and 15 every 28 days. The maximum tolerated dose (MTD) and the dose-limiting toxicity of the combination were evaluated at the first cycle.

RESULTS

Twenty-four ROC patients were enrolled in six dose-levels. Most patients had high-grade serous metastatic ovarian cancer (41.7%) and performance status score of 0-1 (95.8%). For 12 patients (50%) treatment was 2nd line and for 12 >2nd line. Eighty-eight cycles were administered with a median of three cycles per patient. The MTD was not reached and grade 3-4 (3.4% and 2.3% of cycles, respectively) neutropenia and grade 4 (3.4% of cycles) thrombocytopenia were the main adverse events. There was no case of febrile neutropenia. Non-hematologic toxicity was mild with grade 2 fatigue being the most frequent complain. The recommended MTD doses of the combination were topotecan 1.75 mg/m2 and gemcitabine 1200 mg/m2 on days 1, 8, and 15 every 28 days. Two complete (8.3%) and three (12.5%) partial responses were achieved (ORR: 20.8%).

CONCLUSIONS

The weekly administration of gemcitabine/topotecan regimen in patients with pretreated metastatic ovarian cancer is an active chemotherapy combination, even in heavily pretreated patients, with a manageable toxicity profile which merits further investigation.

Pegylated liposomal doxorubicin re-challenge in patients with ovarian cancer relapse: a multicenter retrospective study

Background

Pegylated liposomal doxorubicin (PLD) is an active and well-tolerable treatment in ovarian cancer relapse, either alone or in combination with other drugs. No data are available on the possibility to rechallenge PLD treatment in long survivor patients with recurrent ovarian cancer, as evaluated for platinum agent, paclitaxel and gemcitabine. The aim of the present study was to evaluate the anti-tumor activity and the toxicity profile of re-challenge of PLD in recurrent ovarian cancer patients.

Methods

Data on 27 patients with epithelial ovarian cancer treated in the last ten years (2007-2017) with palliative PLD rechallenge were included in this multicenter retrospective Italian study.

Results

The objective response rate to PLD re-treatment were complete response in 19%, partial response in 30% and stable disease in 37%. Only 1 case of G4 hematological toxicity was reported. No patient experienced severe cardiac impairment (G2-4).

Conclusion

PLD rechallenge represents an active and safe possibility of treatment for long survivor ovarian cancer patients.

MAL gene overexpression as a marker of high-grade serous ovarian carcinoma stem-like cells that predicts chemoresistance and poor prognosis

BACKGROUND

The existence of cancer stem cells (CSCs) within a tumor bulk has been demonstrated for many solid tumors including epithelial ovarian carcinoma (EOC). CSCs have been associated to tumor invasion, metastasis and development of chemoresistant recurrences. In this context, we aim to characterize EOC CSCs from the molecular point of view in order to identify potential biomarkers associated with chemoresistance.

METHODS

We isolated a population of cells with stem-like characteristics (OVA-BS4 spheroids) from a primary human EOC cell line under selective conditions. OVA-BS4 spheroids were characterized for drug response by cytotoxicity assays and their molecular profile was investigated by microarray and RT-qPCR. Finally, we performed a gene expression study in a cohort of 74 high-grade serous EOC (HGSOC) patients by RT-qPCR.

RESULTS

Spheroids exhibited properties of self-renewal and a pronounced expression of well-known stem cell genes. Moreover, they demonstrated greater resistance towards several anticancer drugs compared to parent cell line, consistent with their higher ABCG2 gene expression. From microarray studies MAL (T-cell differentiation protein) emerged as the most up-regulated gene in spheroids, compared to parent cell line. In HGSOC patients, MAL was significantly overexpressed in platinum-resistant compared to platinum-sensitive patients and resulted as an independent prognostic marker of survival.

CONCLUSIONS

This investigation provides an important contribution to the identification of molecular markers of ovarian CSCs and chemoresistance. Successful translation of molecular findings would lead to a better comprehension of the mechanisms triggering chemoresistant recurrences, to the individuation of novel therapeutic targets and to the personalization of treatment regimens.

FOXM1 expression is significantly associated with chemotherapy resistance and adverse prognosis in non-serous epithelial ovarian cancer patients

BACKGROUND

Epithelial ovarian cancer (EOC) is a spectrum of different diseases, which makes their treatment a challenge. Forkhead box M1 (FOXM1) is an oncogene aberrantly expressed in many solid cancers including serous EOC, but its role in non-serous EOCs remains undefined. We examined FOXM1 expression and its correlation to prognosis across the three major EOC subtypes, and its role in tumorigenesis and chemo-resistance in vitro.

METHODS

Gene signatures were generated by microarray for 14 clear-cell and 26 endometrioid EOCs, and 15 normal endometrium snap-frozen biopsies. Validation of FOXM1 expression was performed by RT-qPCR and immunohistochemistry in the same samples and additionally in 50 high-grade serous EOCs and in their most adequate normal controls (10 luminal fallopian tube and 20 ovarian surface epithelial brushings). Correlations of FOXM1 expression to clinic-pathological parameters and patients' prognosis were evaluated by Kaplan-Meier and Cox proportional-hazards analyses. OVCAR-3 and two novel deeply characterized EOC cell lines (EOC-CC1 and OSPC2, with clear-cell and serous subtype, respectively) were employed for in vitro studies. Effects of FOXM1 inhibition by transient siRNA transfection were evaluated on cell-proliferation, cell-cycle, colony formation, invasion, and response to conventional first- and second-line anticancer agents, and to the PARP-inhibitor olaparib. Gene signatures of FOXM1-silenced cell lines were generated by microarray and confirmed by RT-qPCR.

RESULTS

A significant FOXM1 mRNA up-regulation was found in EOCs compared to normal controls. FOXM1 protein overexpression significantly correlated to serous histology (p = 0.001) and advanced FIGO stage (p = 0.004). Multivariate analyses confirmed FOXM1 protein overexpression as an independent indicator of worse disease specific survival in non-serous EOCs, and of shorter time to progression in platinum-resistant cases. FOXM1 downregulation in EOC cell lines inhibited cell growth and clonogenicity, and promoted the cytotoxic effects of platinum compounds, doxorubicin hydrochloride and olaparib. Upon FOXM1 knock-down in EOC-CC1 and OSPC2 cells, microarray and RT-qPCR analyses revealed the deregulation of several common and other unique subtype-specific FOXM1 putative targets involved in cell cycle, metastasis, DNA repair and drug response.

CONCLUSIONS

FOXM1 is up-regulated in all three major EOCs subtypes, and is a prognostic biomarker and a potential combinatorial therapeutic target in platinum resistant disease, irrespective of tumor histology.

Tumor Marker Ordering: Do Not Lose Control: A Prospective Clinical Trial

OBJECTIVES

In this study, we evaluated the extent of inappropriate tumor marker (TM) ordering in a secondary care setting, approximately 6 years after the introduction of local guidelines, and we identified the main factors potentially influencing clinicians when performing an inappropriate TM request.

METHODS

For this purpose, we regularly checked all requests containing more than two TMs. During the 21-month audit, the rate of rejected requests amounted to 3.6%. Several of those were performed for diagnostic purposes. The most frequent and inappropriately requested TMs were carcinoembryonic antigen and carbohydrate antigen 19.9.

RESULTS

The inappropriateness of requests appeared to be linked to the need for more education and knowledge on their clinical applicability and limitations. The clinical motivation was generally associated with patients displaying nonspecific signs/symptoms (ie, weight loss with worsening general conditions), having an incidentally positive result to some recently performed TM tests, or being tested by a TM to avoid more expensive diagnostic imaging procedures.

CONCLUSIONS

Our data show that real-time control and management of inappropriate requests by laboratory professionals may be relevant to increase the clinical efficacy of TM testing and useful in perspective to drive the introduction of new validated biomarkers.