DNA Damage Response Alterations in Ovarian Cancer: From Molecular Mechanisms to Therapeutic Opportunities

The DNA damage response (DDR), a set of signaling pathways for DNA damage detection and repair, maintains genomic stability when cells are exposed to endogenous or exogenous DNA-damaging agents. Alterations in these pathways are strongly associated with cancer development, including ovarian cancer (OC), the most lethal gynecologic malignancy. In OC, failures in the DDR have been related not only to the onset but also to progression and chemoresistance. It is known that approximately half of the most frequent subtype, high-grade serous carcinoma (HGSC), exhibit defects in DNA double-strand break (DSB) repair by homologous recombination (HR), and current evidence indicates that probably all HGSCs harbor a defect in at least one DDR pathway. These defects are not restricted to HGSCs; mutations in ARID1A, which are present in 30% of endometrioid OCs and 50% of clear cell (CC) carcinomas, have also been found to confer deficiencies in DNA repair. Moreover, DDR alterations have been described in a variable percentage of the different OC subtypes. Here, we overview the main DNA repair pathways involved in the maintenance of genome stability and their deregulation in OC. We also recapitulate the preclinical and clinical data supporting the potential of targeting the DDR to fight the disease.

Efficacy and safety of trabectedin for the treatment of advanced uterine or ovarian carcinosarcoma: Results of a phase II multicenter clinical trial (MITO-26)

OBJECTIVE

This open-label phase II clinical trial evaluated the antitumor activity and safety of trabectedin in patients with advanced ovarian (OC) or uterine carcinosarcomas (UC).

METHODS

Eligible patients were adults (≥18 years) with histologically proven recurrent OC/UC not amenable to surgery or radiotherapy who received up to two prior chemotherapy lines. Trabectedin 1.3 mg/m² was administered as a 3-h infusion every three weeks. The primary endpoint was objective response rate (ORR) as per RECIST v.1.1. If at least 8 of 43 patients (18.6%) achieve an objective response, trabectedin would be declared worthy for further investigations.

RESULTS

Forty-five patients with either OC (n = 32) or UC (n = 13) from seven MITO centers across Italy were enrolled. The ORR was 11.9% (90% CI: 6-23) and included two patients with a complete response and three with a partial response. Eight patients (19.0%) had disease stabilization for a disease control rate of 31.0% (90% CI: 20-44). Median progression-free survival was 2.01 months (95% CI: 1.78-2.30) and median overall survival was 4.64 months (95% CI: 3.19-8.29). Neutrophil count decreases (n = 8, 18.2%) and transaminase increases (n = 6, 13.6%) were the most common grade 3-5 adverse events related with trabectedin. Two patients died due to trabectedin-related grade 5 hematological toxicity.

CONCLUSION

Although trabectedin did not meet the prespecified activity criteria, it confers modest but clinically meaningful benefit to patients with advanced OC/UC as being as effective as any other available treatment for this indication. The toxicity profile appears in line with that previously reported for the drug.

Trabectedin in Cancers: Mechanisms and Clinical Applications

Trabectedin, a tetrahydroisoquinoline alkaloid, is the first marine antineoplastic agent approved with special anticancer mechanisms involving DNA binding, DNA repair pathways, transcription regulation and regulation of the tumor microenvironment. It has favorable clinical applications, especially for the treatment of patients with advanced soft tissue sarcoma, who failed in anthracyclines and ifosfamide therapy or could not receive these agents. Currently, trabectedin monotherapy regimen and regimens of combined therapy with other agents are both widely used for the treatment of malignancies, including soft tissue sarcomas, ovarian cancer, breast cancer, and non-small-cell lung cancer. In this review, we summarized the basic information and some updated knowledge on trabectedin, including its molecular structure, metabolism in various cancers, pharmaceutical mechanisms, clinical applications, drug combination, and adverse reactions, along with prospections on its possibly more optimal use in cancer treatment.

Trabectedin plus durvalumab in patients with advanced pretreated soft tissue sarcoma and ovarian carcinoma (TRAMUNE): an open-label, multicenter phase Ib study

PURPOSE

Trabectedin has shown pre-clinical synergy with immune-checkpoint inhibitors in pre-clinical models.

EXPERIMENTAL DESIGN

TRAMUNE is a phase Ib study investigating trabectedin combined with durvalumab trough a dose-escalation phase and two expansion cohorts (soft tissue sarcoma and ovarian carcinoma). Trabectedin was given at three dose levels (1 mg/m2, 1.2 mg/m2 and 1.5 mg/m2) on day 1, in combination with durvalumab, 1120 mg on day 2, every 3 weeks. The primary endpoints were the recommended phase II dose (RP2D) of trabectedin combined with durvalumab and the objective response rate (ORR) as per RECIST 1.1. The secondary endpoints included safety, 6-month progression-free rate (PFR), progression-free survival (PFS), overall survival, and biomarker analyses.

RESULTS

40 patients were included (dose escalation: n=9; STS cohort: n=16; ovarian cohort: n=15, 80% platinum resistant/refractory). The most frequent toxicities were grade 1-2 fatigue, nausea, neutropenia, and alanine/aspartate aminotransferase increase. One patient experienced a dose-limiting toxicity at dose level 2. Trabectedin at 1.2 mg/m2 was selected as the RP2D. In the STS cohort, 43% of patients experienced tumor shrinkage, the ORR was 7% (95% CI 0.2 - 33.9) and the 6-month PFR 28.6% (95% CI 8.4-58.1). In the ovarian carcinoma cohort, 43% of patients experienced tumor shrinkage, the ORR was 21.4% (95% CI 4.7 - 50.8) and the 6-month PFR 42.9% (95% CI 17.7 - 71.1). Baseline levels of PD-L1 expression and CD8-positive T-cell infiltrates were associated with PFS in ovarian carcinoma patients.

CONCLUSIONS

Combining trabectedin and durvalumab is manageable. Promising activity is observed in platinum-refractory ovarian carcinoma patients.

Trabectedin-Related Heart Failure: Case Report and a Systematic Review of the Literature

New drugs come not only with benefits but also with unexpected toxicities which need to be promptly recognized and managed. Starting from a scholar case of acute heart failure with preserved ejection fraction following the administration of trabectedin (ET-743, Yondelis^®) in a patient with a metastatic solitary fibrous tumor, we performed a systematic review of the literature encompassing the results of previous cardiac safety analysis published ten years ago, a review of clinical trials published during the last 10 years as well as single-case descriptions related to trabectedin cardiotoxicity. The estimated incidence of cardiac toxicity was 3,4% among patients receiving trabectedin, with recent data suggesting a higher rate of heart failure than previously recognized. Previous or concomitant anthracyclines exposure may represent a risk factor. Assaying for NT-pro-BNP may be useful for the early detection of individuals with trabectedin-induced heart failure.

Trabectedin (Yondelis®) as a Therapeutic Option in Gynecological Cancers: A Focus on its Mechanisms of Action, Clinical Activity and Genomic Predictors of Drug Response

The use of predictive biomarkers provides potential individualized cancer therapeutic options to prevent therapy failure as well as serious toxicities. Several recent studies showed that predictive and prognostic biomarkers are a notable personalized strategy to improve patients' care in several cancers. Trabectedin (Yondelis®) is a cytotoxic agent, derived from a marine organism, harbouring a significant antitumor activity against several cancers such as soft tissue sarcoma, ovarian, and breast cancers. Recently and with the advent of molecular genetic testing, BRCA mutational status was found as an important predictor of response to this anticancer drug, especially in gynecological cancers. The aim of this updated review is to discuss the mechanisms of action of trabectedin against the wellknown cancer hallmarks described until today. The current advances were also examined related to genomic biomarkers that can be used in the future to predict the efficacy of this potent anticancer natural molecule in various gynecological cancers.

Trabectedin for reversing platinum resistance and resensitization to platinum in patients with recurrent ovarian cancer

Aims: We evaluated trabectedin in patients with platinum-resistant/refractory and partially platinum-sensitive recurrent ovarian cancer and the outcomes after reintroduction of platinum. Methods: Twenty-seven patients (platinum-resistant/refractory n = 24/PPS; n = 3) treated with trabectedin were retrospectively analyzed. Results: Trabectedin resulted in an objective response rate (ORR) of 18.2% with a 59.1% of disease control rate (ORR plus stable disease). The median progression-free and overall survival were 3.0 and 21.3 months, respectively. Subsequently, 17 patients were retreated with platinum and yield an ORR of 41.2% and DCR of 47.0%. The median progression-free and overall survival after platinum rechallenge were 5.0 and 14.7 months, respectively. Conclusion: Our results suggest that trabectedin may contribute to resensitize tumor cells to platinum rechallenge.

Starvation tactics using natural compounds for advanced cancers: pharmacodynamics, clinical efficacy, and predictive biomarkers

The high mortality associated with oncological diseases is mostly due to tumors in advanced stages, and their management is a major challenge in modern oncology. Angiogenesis is a defined hallmark of cancer and predisposes to metastatic invasion and dissemination and is therefore an important druggable target for cancer drug discovery. Recently, because of drug resistance and poor prognosis, new anticancer drugs from natural sources targeting tumor vessels have attracted more attention and have been used in several randomized and controlled clinical trials as therapeutic options. Here, we outline and discuss potential natural compounds as salvage treatment for advanced cancers from recent and ongoing clinical trials and real-world studies. We also discuss predictive biomarkers for patients' selection to optimize the use of these potential anticancer drugs.

Restoring platinum sensitivity in recurrent ovarian cancer by extending the platinum-free interval: Myth or reality?

The platinum-free interval is the most important predictive factor of a response to subsequent lines of chemotherapy and the most important prognostic factor for progression-free and overall survival in patients with recurrent epithelial ovarian cancer. A nonplatinum regimen is generally considered the most appropriate approach when the disease recurs very early after the end of chemotherapy, whereas platinum-based chemotherapy is usually adopted when the platinum-free interval exceeds 12 months. However, the therapeutic management of patients with intermediate sensitivity (ie, when the relapse occurs between 6 and 12 months) remains debatable. Preclinical and clinical data suggest that the extension of platinum-free interval (using a nonplatinum-based regimen) might restore platinum sensitivity, thus allowing survival improvement. The objective of this review was to critically analyze preclinical and clinical evidences supporting this hypothesis. Cancer 2017;123:3450-9. © 2017 American Cancer Society.

Real-World Management of Trabectedin/Pegylated Liposomal Doxorubicin in Platinum-Sensitive Recurrent Ovarian Cancer Patients: A National Survey

BACKGROUND

Trabectedin (T) plus pegylated liposomal doxorubicin (PLD) is approved for treatment of platinum-sensitive recurrent ovarian cancer (ROC). Despite the recommendations and guidelines, variations in managing T/PLD administration in routine clinical practice cannot be excluded. We aimed at setting up an Italian survey collecting data about management of T/PLD administration in ROC patients.

METHODS

We carried out the development of a questionnaire-based survey on routine clinical practice in the management of ROC patients administered T/PLD. The survey registered the physicians' approach to modification/discontinuation of treatment, type of modifications, reasons why, and so on. The survey was transmitted to medical oncologists and gynecologic oncologists practicing in national centers/institutions.

RESULTS

Fifty-eight Italian centers/institutions returned the compiled questionnaire; participants practiced at community cancer centers or hospitals (56.9%), academic institutions (36.2%), and other settings (private clinics, etc) (6.9%). There was no statistically significant difference in the distribution of practice setting according to geographic areas. Most responders were medical oncologists (84.5%) and were members (82.8%) of at least 1 scientific society or cooperative group. Almost 31.5% of responders reported interruption of the whole treatment, mostly because of toxicity (41.2%), followed by patients' choice (29.4%), or achievement of clinical benefit (23.5%). Dose reduction was referred by 47.4% of responders. Reduction of dose for both drugs was referred by 88.5% of responders, and the extent of dose reduction ranged between 10% and 30%.

CONCLUSIONS

This survey highlights the gaps in transposing evidence-based or consensus guidelines in the real-world management of T/PLD administration; these findings could be useful in order to focus the attention on specific knowledge and/or experience gaps and plan pertinent educational programs.

Drug Monographs: Trabectedin and Trifluridine-Tipiracil

The complexity of cancer chemotherapy requires pharmacists be familiar with the complicated regimens and highly toxic agents used. This column reviews various issues related to preparation, dispensing, and administration of antineoplastic therapy, and the agents, both commercially available and investigational, used to treat malignant diseases.

Trabectedin for the treatment of breast cancer

INTRODUCTION

Trabectedin is an anti-tumor compound registered in Europe and in several other countries, for the second-line treatment of soft tissue sarcoma (STS) and for ovarian cancer in combination with liposomal doxorubicin. Trabectedin inhibits cancer cell proliferation mainly affecting the transcription regulation. Trabectedin also acts as a modulator of tumor microenvironment by reducing the number of tumor associated macrophages (TAM). Because of its unique mechanism of action, trabectedin has the potential to act as antineoplastic agent also in several solid malignancies, including breast cancer (BC).

AREAS COVERED

This article reviews the preclinical and clinical data of trabectedin focusing on development in metastatic BC (mBC). Comments regarding the nature and the results of these trials are included.

EXPERT OPINION

Trabectedin is thought to have a crucial activity with defective DNA-repair machinery and also in modulating the tumor micro-environment and the immune-system of cancer patients. From the current available data, we recognize a potential activity of trabectedin in mBC and support the renewed efforts to better elucidate the value of trabectedin in this indication.

Phase II trial of salvage therapy with trabectedin in metastatic pancreatic adenocarcinoma

PURPOSE

No standard salvage chemotherapy has been identified for metastatic pancreatic adenocarcinoma (mPA), and there is an urgent need for active agents against this disease. This phase II trial explored the activity of trabectedin in mPA progressing after gemcitabine-based first-line chemotherapy.

METHODS

Patients with gemcitabine-resistant disease received trabectedin 1.3 mg/m(2) as a 3-h intravenous continuous infusion every 3 weeks until disease progression or unacceptable toxicity or for a maximum of 6 months. The primary endpoint was progression-free survival rate at 6 months (PFS-6). Since trabectedin modulates the production of selected inflammatory mediators, this study also aimed to identify inflammatory biomarkers predictive for response to trabectedin.

RESULTS

Between February 2011 and February 2012, 25 patients received trabectedin. PFS-6 was 4%, median PFS 1.9 months (range 0.8-7.4), and median overall survival 5.2 months (range 1.1-24.3). Grade >2 toxicity consisted of neutropenia in 44% of patients, febrile neutropenia and thrombocytopenia both in 12%, anemia in 8%, fatigue in 12%, and AST and ALT increase in 8 and 4%, respectively. Trabectedin was shown to modulate the production of inflammatory mediators, and at disease progression, levels of a subgroup of cytokines/chemokines were modified. Furthermore, tissue analysis identified 30 genes associated with better prognosis.

CONCLUSIONS

Although it has shown some ability to modulate inflammatory process, single-agent trabectedin had no activity as salvage therapy for mPA.

A comprehensive safety evaluation of trabectedin and drug-drug interactions of trabectedin-based combinations

Trabectedin (Yondelis(®)) is a potent marine-derived antineoplastic drug with high activity against various soft tissue sarcoma (STS) subtypes as monotherapy, and in combination with pegylated liposomal doxorubicin (PLD) for the treatment of patients with relapsed platinum-sensitive ovarian cancer. This article reviews the safety and pharmacokinetic profiles of trabectedin. Records were identified using predefined search criteria using electronic databases (e.g. PubMed, Cochrane Library Database of Systematic Reviews). Primary peer-reviewed articles published between 1 January 2006 and 1 April 2014 were included. The current safety and tolerability profile of trabectedin, based on the evaluation in clinical trials of patients treated with the recommended treatment regimens for STS and recurrent ovarian cancer, was reviewed. Trabectedin as monotherapy or in combination with PLD, was not associated with cumulative and/or irreversible toxicities, such as cardiac, pulmonary, renal, or oto-toxicities, often observed with other common chemotherapeutic agents. The most common adverse drug reactions (ADRs) were myelosuppression and transient hepatic transaminase increases that were usually not clinically relevant. However, trabectedin administration should be avoided in patients with severe hepatic impairment. Serious and fatal ADRs were likely to be related to pre-existing conditions. Doxorubicin or PLD, carboplatin, gemcitabine, or paclitaxel when administered before trabectedin, did not seem to influence its pharmacokinetics. Cytochrome P450 (CYP) 3A4 has an important role in the metabolism of trabectedin, suggesting a risk of drug-drug interactions with trabectedin used in combination with other CYP3A4 substrates. Trabectedin has a favorable risk/efficacy profile, even during extended treatment in pretreated patients.

Trabectedin plus pegylated liposomal doxorubicin: retrospective analysis in heavily pretreated platinum-sensitive ovarian cancer

Purpose

This retrospective analysis evaluated treatment with trabectedin plus pegylated liposomal doxorubicin (PLD) in 34 heavily pretreated patients (median number of previous lines, 3; range, 2-10) with platinum-sensitive relapsed ovarian cancer (ROC) at a single center in Italy.

Methods

Trabectedin/PLD treatment consisted of trabectedin administered every 3 weeks as a 3-hour intravenous (i.v.) infusion at a dose of 1.1 mg/m², immediately after PLD 30 mg/m² i.v. infusion. Study objectives were the evaluation of the objective response rate (ORR), progression-free survival (PFS) and overall survival (OS).

Results

Three complete responses and 8 partial responses were observed, with an ORR of 32.4% (95% CI, 17.450.5%). Median PFS was 6.1 months (95% CI, 4.4-8.9 months). Median OS was 16.3 months (95% CI, 6.8-23.5). Most responses (9 of 11) were found in patients with partially platinum-sensitive disease (ORR 40.9% in this subset; median PFS 6.8 months and median OS 20.8 months). Grade 3 treatment-related adverse events consisted of nausea/vomiting (n = 5; 14.7%), mucositis (n = 2; 5.9%), alanine aminotransferase increase, anemia and neutropenia (n = 1 each; 2.9%).

Conclusions

The overall findings appear consistent with those previously observed in a randomized controlled clinical trial, and support the use of trabectedin/PLD in heavily pretreated patients with platinum-sensitive ROC, especially those with partially platinum-sensitive disease.

Trabectedin therapy as an emerging treatment strategy for recurrent platinum-sensitive ovarian cancer

Epithelial ovarian cancer (OC) is a common gynecologic malignancy in women. The standard treatment for OC is maximal cytoreductive surgical debulking followed by platinum-based chemotherapy. Despite the high response rate to primary therapy, approximately 85% of patients will develop recurrent ovarian cancer (ROC). This review identifies the clinical use of trabectedin in the treatment algorithm for ROC, with specific emphasis on platinum-sensitive ROC, for which trabectedin in combination with pegylated liposomal doxorubicin has been approved as a treatment protocol. The main mechanisms of action of trabectedin at the cellular level and in the tumor microenvironment is also discussed as bases for identifying biomarkers for selecting patients who may largely benefit from trabectedin-based therapies.

Clinical utility of trabectedin for the treatment of ovarian cancer: current evidence

Among the pharmaceutical options available for treatment of ovarian cancer, attention has been increasingly focused on trabectedin (ET-743), a drug which displays a unique mechanism of action and has been shown to be active in several human malignancies. Currently, single agent trabectedin is approved for treatment of patients with advanced soft tissue sarcoma after failure of anthracyclines and ifosfamide, and in association with pegylated liposomal doxorubicin for treatment of patients with relapsed partially platinum-sensitive ovarian cancer. This review aims at summarizing the available evidence about the clinical role of trabectedin in the management of patients with epithelial ovarian cancer. Novel perspectives coming from a better understanding of trabectedin mechanisms of action and definition of patients subgroups likely susceptible to benefit of trabectedin treatment are also presented.

Biology of ovarian cancer and trabectedin mechanism of action

More than 50% of patients with ovarian cancer have genetic alterations in the homologous repair pathway. Trabectedin appears to induce damage more readily in tumor cells with defects in the homologous repair system. Moreover, trabectedin inhibits monocyte differentiation into tumor-associated macrophages and inhibits the production of inflammatory mediators such as IL-6. In patients with platinum-sensitive, relapsed ovarian cancer, trabectedin plus pegylated liposomal doxorubicin was associated with a trend towards improved overall survival by extending the platinum-free interval. These clinical effects could possibly be attributed to actions of trabectedin on the tumor microenvironment (e.g., a reduction of IL-6). Thus, trabectedin is an agent with mechanisms of action especially appropriate for targeting key processes in the biology of ovarian cancer.

Trabectedin as single agent in the salvage treatment of heavily treated ovarian cancer patients: a retrospective, multicenter study

OBJECTIVE

The aim of this multicenter, retrospective study was to evaluate the efficacy and the safety of single agent Trabectedin (ET-743, Yondelis) in very heavily treated, relapsed ovarian cancer (ROC) patients.

PATIENTS AND METHODS

Response to treatment was classified according to RECIST criteria. Progression-free (PFS), and overall survival (OS) were also assessed.

RESULTS

98 patients were analyzed (originally 67 platinum sensitive, and 31 platinum refractory/resistant). Median number of previous regimens was 4 (range: 1-6). In the whole population, overall response rate (ORR) was 27.5%; stable disease (SD) was observed in 33 patients (33.6%), and clinical benefit was achieved in 60 cases (61.2%). ORR was 38.6% in fully platinum sensitive population, and 26.1% in partially platinum sensitive patients. In platinum refractory/resistant disease, ORR was 12.9%. Overall, median PFS and OS were 5, and 13 months, respectively. Patients responding to Trabectedin showed a more favorable PFS (median = 9 months) than patients with SD (median = 6 months), or progression (median = 2 months). Median OS of responding patients was 18 months compared to 14 months in SD patients, and 9 months in progressing patients. Grade 3-4 neutropenia was observed in 17 (17.3%) patients. Transient and non-cumulative Grade 3-4 AST and ALT level elevation was found in 7 (7.1%), and 13 (13.3%) cases, respectively. There was 1 case of Grade 3, and 1 case of Grade 4 cardiac toxicity.

CONCLUSIONS

Trabectedin, as a single agent, retains its efficacy in terms of rate of ORR and clinical benefit in heavily treated ROC patients, especially in the group of platinum sensitive disease.

Comparison of in vitro and in vivo biological effects of trabectedin, lurbinectedin (PM01183) and Zalypsis® (PM00104)

This study: (i) investigated the in vitro cytotoxicity and mode of action of lurbinectedin (PM01183) and Zalypsis® (PM00104) compared with trabectedin in cell lines deficient in specific mechanisms of repair, (ii) evaluated their in vivo antitumor activity against a series of murine tumors and human xenografts. The antiproliferative activity, the DNA damage and the cell cycle perturbations induced by the three compounds on tumor lines were very similar. Nucleotide Excision Repair (NER) deficient cells were approximately fourfold more resistant to trabectedin, lurbinectedin and Zalypsis®. Cells deficient in non-homologous end joining (NHEJ), MRN complex and translesion synthesis (TLS) were slightly more sensitive to the three compounds (approximately fivefold) while cells deficient in homologous recombination (HR) were markedly more sensitive (150-200-fold). All three compounds showed a good antitumor activity in several in vivo models. Lurbinectedin and trabectedin had a similar pattern of antitumor activity in murine tumors and in xenografts, whereas Zalypsis® appeared to have a distinct spectrum of activity. The fact that no relationship whatsoever was found between the in vitro cytotoxic potency and the in vivo antitumor activity, suggests that in addition to direct cytotoxic mechanisms other host-mediated effects are involved in the in vivo pharmacological effects.

Trabectedin as single agent in relapsed advanced ovarian cancer: results from a retrospective pooled analysis of three phase II trials

Three phase II studies evaluated trabectedin monotherapy as second-/third-line therapy in patients with refractory/recurrent ovarian cancer (ROC). Three different schedules were investigated: 3-h infusion every 3 weeks (3-h_q3w), 24-h infusion q3w (24-h_q3w), and 3-h weekly infusion for 3 weeks of a 4-week cycle. This retrospective pooled analysis evaluated the efficacy and the safety profile of trabectedin according to each administered regimen. Data from 295 patients were used to compare weekly versus q3w schedules, and 3-h versus 24-h infusion given q3w. Both q3w regimens showed higher overall response rate (36 vs. 16 %; p = 0.0001), disease control rate (66 vs. 46 %; p = 0.0007), and longer median progression-free survival (5.6 vs. 2.8 months; p < 0.0001) than the weekly schedule. Comparable activity was observed for the 3- and 24-h infusions q3w. Common adverse events were nausea, fatigue, vomiting, transient neutropenia, and transaminase increases. A better safety profile regarding neutropenia, fatigue, and vomiting was seen for the 3-h_q3w regimen as compared to the 24-h_q3w one. Trabectedin given as a single agent q3w as 3-h infusion is the schedule of choice for the treatment of ROC, and its efficacy and safety profile favorably compares with other active salvage treatments.

Growth modulation index as metric of clinical benefit assessment among advanced soft tissue sarcoma patients receiving trabectedin as a salvage therapy

BACKGROUND

The growth modulation index (GMI) is the ratio of time to progression with the nth line (TTP(n)) of therapy to the TTP(n)(-1) with the n-1th line. GMI >1.33 is considered as a sign of activity in phase II trials.

PATIENTS AND METHODS

This retrospective analysis evaluated the concordance between the GMI and the efficacy outcomes in 279 patients with advanced soft tissue sarcoma (ASTS) treated with trabectedin 1.5 mg/m² (24-h infusion every 3 weeks) in four phase II trials.

RESULTS

One hundred and forty-two (51%) patients received one prior line and 137 ≥ 2 lines. The median TTP(n) was 2.8 months (range 0.2-26.8), whereas the median TTP(n)(-1) was 4.0 months (0.3-79.5). The median GMI was 0.6 (0.0-14.4). Overall, 177 patients (63%) had a GMI <1; 21 (8%) a GMI equal to 1-1.33 and 81 (29%) a GMI >1.33, which correlated with the median overall survival in those patients (9.1, 13.9 and 23.8 months, respectively, P = 0.0005). A high concordance rate between the GMI and response rate (P < 0.0001) and progression-free survival (PFS, P < 0.0001) was observed. Good performance status (PS) was the only factor associated with GMI >1.33 (PS = 0; P < 0.04).

CONCLUSIONS

A high GMI was associated with favorable efficacy outcomes in patients treated with trabectedin. Further research is needed to assess GMI as an indicator in this setting.

A retrospective analysis of antitumour activity with trabectedin in translocation-related sarcomas

AIMS

Approximately 20% of soft tissue sarcomas (STS) have subtype-specific chromosomal translocations; these generate chimeric oncoproteins which can act as abnormal transcription factors. Since trabectedin can bind to DNA and displace transcription factors, antitumour activity was explored in translocation-related sarcoma (TRS) subtypes.

METHODS

The current retrospective pooled analysis includes data from 81 patients with TRS treated in 8 phase II trials.

RESULTS

TRS subtypes were: synovial sarcoma (SS, n=45), myxoid-round cell liposarcoma (MRC-L-sarcoma, n=27), alveolar soft part sarcoma (ASPS, n=4), endometrial stromal sarcoma (ESS, n=3) and clear cell sarcoma (CCS, n=2). All but one patient had received prior chemotherapy (median of 2 lines). Patients received a median of 4 trabectedin cycles (range, 1-48; median dose intensity=0.40 mg/m(2)/week). Partial responses according to Response Evaluation Criteria in Solid Tumours (RECIST) occurred in 8 patients (ORR=10%; 95% CI, 4-19%): four in MRC-L-sarcoma; three in SS and one in ESS. Tumour control rate (ORR plus stable disease) was 59% (95% CI, 48-70%). Median PFS was 4.1 months (6-month PFS rate=40%). Median overall survival was 17.4 months (survival rate at 12 months=60%). Trabectedin had a manageable safety profile.

CONCLUSION

Trabectedin demonstrates encouraging disease control in TRS. Since these promising results were generally noted in patients following chemotherapy, a phase III randomised trial in first-line is ongoing to compare trabectedin with doxorubicin-based chemotherapy in patients with TRS.

A systems biology approach to characterize the regulatory networks leading to trabectedin resistance in an in vitro model of myxoid liposarcoma

Trabectedin, a new antitumor compound originally derived from a marine tunicate, is clinically effective in soft tissue sarcoma. The drug has shown a high selectivity for myxoid liposarcoma, characterized by the translocation t(12;16)(q13; p11) leading to the expression of FUS-CHOP fusion gene. Trabectedin appears to act interfering with mechanisms of transcription regulation. In particular, the transactivating activity of FUS-CHOP was found to be impaired by trabectedin treatment. Even after prolonged response resistance occurs and thus it is important to elucidate the mechanisms of resistance to trabectedin. To this end we developed and characterized a myxoid liposarcoma cell line resistant to trabectedin (402-91/ET), obtained by exposing the parental 402-91 cell line to stepwise increases in drug concentration. The aim of this study was to compare mRNAs, miRNAs and proteins profiles of 402-91 and 402-91/ET cells through a systems biology approach. We identified 3,083 genes, 47 miRNAs and 336 proteins differentially expressed between 402-91 and 402-91/ET cell lines. Interestingly three miRNAs among those differentially expressed, miR-130a, miR-21 and miR-7, harbored CHOP binding sites in their promoter region. We used computational approaches to integrate the three regulatory layers and to generate a molecular map describing the altered circuits in sensitive and resistant cell lines. By combining transcriptomic and proteomic data, we reconstructed two different networks, i.e. apoptosis and cell cycle regulation, that could play a key role in modulating trabectedin resistance. This approach highlights the central role of genes such as CCDN1, RB1, E2F4, TNF, CDKN1C and ABL1 in both pre- and post-transcriptional regulatory network. The validation of these results in in vivo models might be clinically relevant to stratify myxoid liposarcoma patients with different sensitivity to trabectedin treatment.

A comprehensive safety analysis confirms rhabdomyolysis as an uncommon adverse reaction in patients treated with trabectedin

PURPOSE

This analysis determined the incidence of serious rhabdomyolysis events reported during trabectedin treatment since the first phase I clinical trial in April 1996 up to September 2010.

METHODS

Search was done in the Yondelis(®) Pharmacovigilance and Clinical Trials databases using a list of terms according to the Medical Dictionary for Regulatory Activities (MedDRA, v. 13.1), followed by a medical review of all cases retrieved. Total estimated sample was 10,841 patients: 2,789 from clinical trials; 3,926 from compassionate use programs; and 4,126 treated in the marketplace. Two groups were identified: (1) rhabdomyolysis and (2) clinically relevant creatine phosphokinase (CPK) increases without acute renal failure (ARF). Descriptive analysis included demographic, clinical/laboratory data, and contributing/confounding factors. Potential predictive factors were evaluated by multivariate stepwise logistic regression analysis. Possible changes of pharmacokinetics (PK) in patients with rhabdomyolysis were explored using a population PK model.

RESULTS

The global incidence of rhabdomyolysis was 0.7%, and most cases occurred in Cycle 2 of treatment. The incidence of fatal cases was 0.3%. None of the variables evaluated to detect potential risk factors of rhabdomyolysis were predictive. Additionally, CPK increases (without ARF) were detected in 0.4% of patients as an incidental finding with good prognosis.

CONCLUSIONS

Rhabdomyolysis is an uncommon event during trabectedin treatment. Multivariate analyses did not show any potential factor that could be predictive or represent a significantly higher risk of developing rhabdomyolysis. Nevertheless, close patient monitoring and adherence to drug administration guidelines may help to limit the incidence of this event.

Trabectedin plus pegylated liposomal doxorubicin in the treatment of patients with partially platinum-sensitive ovarian cancer: current evidence and future perspectives

The effectiveness of platinum re-treatment in relapsed ovarian cancer depends on relapse-free/treatment-free intervals. Platinum agents can be effectively readministered to platinum-sensitive patients (relapsing >12 months after platinum), but efficacy is lower in partially platinum-sensitive (PPS) disease (relapsing 6-12 months after platinum). There is no clear standard treatment challenging PPS patients. Survival data in this subset with chemotherapy combinations such as pegylated liposomal doxorubicin (PLD) plus carboplatin or gemcitabine plus PLD are available from phase II trials ranging from 16 to 21 months. Recent results from OVA-301 phase III randomized trial evaluating trabectedin plus PLD showed the longest median overall survival ever reported in PPS patients (23 months). Subsequent chemotherapy (including platinum-based regimens) was administered later and survival in patients receiving third-line platinum was longer in patients treated with trabectedin plus PLD compared with those treated with PLD alone. These results suggest that prolonging platinum-free interval (PFI) with an effective non-platinum regimen improves outcome with subsequent third-line platinum treatment. An ongoing phase III trial (INOVATYON) aims to demonstrate if the results observed with trabectedin plus PLD in PPS patients are due to PFI extension, and if PFI extension with non-platinum combination prolongs response to subsequent platinum and survival in this population.

Phase II clinical trial of neoadjuvant trabectedin in patients with advanced localized myxoid liposarcoma

BACKGROUND

To evaluate neoadjuvant trabectedin (1.5 mg/m(2) 24-h i.v. infusion every 3 weeks; three to six cycles) in patients with locally advanced myoxid liposarcoma (ML) previously untreated with chemotherapy or radiation.

PATIENTS AND METHODS

Primary efficacy end point was pathological complete response (pCR) or tumoral regression rate. Objective response according to RECIST (v.1.0) was a secondary end point.

RESULTS

Three of 23 assessable patients had pCR [13%; 95% confidence interval (CI), 3% to 34%]. Furthermore, very good and moderate histological responses were observed in another 2 and 10 patients, respectively. Histological decrement in the cellular and vascular tumor component and maturation of tumor cells to lipoblasts were observed in both myoxid and myoxid/round cell variants. Seven patients had partial response according to RECIST (objective response rate of 24%; 95% CI, 10% to 44%). No disease progression was reported. Neoadjuvant trabectedin was usually well tolerated, with a safety profile similar to that described in patients with soft tissue sarcoma or other tumor types.

CONCLUSION

Trabectedin 1.5 mg/m(2) given as a 24-h i.v. infusion every 3 weeks is a therapeutic option in the neoadjuvant setting of ML.

Trabectedin in patients with advanced non-small-cell lung cancer (NSCLC) with XPG and/or ERCC1 overexpression and BRCA1 underexpression and pretreated with platinum

BACKGROUND

Previous studies in sarcoma found that a composite gene signature, including high expression of nucleotide excision repair (NER) genes (XPG and/or ERCC1) and low expression of homologous recombination repair (HR) genes (BRCA1), identifies a highly sensitive population of patients with significantly improved outcome to trabectedin. This exploratory phase II trial evaluated a customized trabectedin treatment according to this gene signature in patients with non-small cell lung cancer (NSCLC) after the failure of standard platinum-based treatment.

METHODS

Patients were selected according to their mRNA expression (elevated XPG and/or ERCC1, with low BRCA1) using the following values as cutoff: XPG=0.99, ERCC1=3.47 and BRCA1=12.00. Trabectedin was administered as a 1.3mg/m(2) 3-hour intravenous infusion every 3 weeks (q3wk). The primary efficacy endpoint was the progression-free survival rate at 3 months. Objective response according to the Response Evaluation Criteria in Solid Tumors (RECIST) was a secondary efficacy endpoint.

RESULTS

Two of 18 evaluable patients (11.1%; 95% CI, 1.38-34.7%) achieved progression-free survival rate at 3 months. The primary efficacy objective (at least 3 of 18 patients being progression-free at 3 months) was not met, and therefore the trial was early finalized. No objective responses per RECIST were achieved. Four patients had stable disease. Median PFS was 1.3 months, and median overall survival was 5.9 months. Trabectedin was usually well tolerated, with a safety profile similar to that described in patients with other tumor types.

CONCLUSIONS

Customized treatment with trabectedin 1.3mg/m(2) 3-h q3wk according to composite gene signature (XPG and/or ERCC1 overexpression, and BRCA1 underexpression) was well tolerated, but had modest activity in NSCLC patients pretreated with platinum. Therefore, further clinical trials with trabectedin as single agent in this indication are not warranted.

Characterization of a new trabectedin-resistant myxoid liposarcoma cell line that shows collateral sensitivity to methylating agents

Myxoid Liposarcomas (MLS), characterized by the expression of FUS-CHOP fusion gene are clinically very sensitive to the DNA binding antitumor agent, trabectedin. However, resistance eventually occurs, preventing disease eradication. To investigate the mechanisms of resistance, a trabectedin resistant cell line, 402-91/ET, was developed. The resistance to trabectedin was not related to the expression of MDR related proteins, uptake/efflux of trabectedin or GSH levels that were similar in parental and resistant cells. The 402-91/ET cells were hypersensitive to UV light because of a nucleotide excision repair defect: XPG complementation decreased sensitivity to UV rays, but only partially to trabectedin. 402-91/ET cells showed collateral sensitivity to temozolomide due to the lack of O(6) -methylguanine-DNA-methyltransferase (MGMT) activity, related to the hypermethylation of MGMT promoter. In 402-91 cells chromatin immunoprecipitation (ChIP) assays showed that FUS-CHOP was bound to the PTX3 and FN1 gene promoters, as previously described, and trabectedin caused FUS-CHOP detachment from DNA. Here we report that, in contrast, in 402-91/ET cells, FUS-CHOP was not bound to these promoters. Differences in the modulation of transcription of genes involved in different pathways including signal transduction, apoptosis and stress response between the two cell lines were found. Trabectedin activates the transcription of genes involved in the adipogenic-program such as c/EBPα and β, in 402-91 but not in 402-91/ET cell lines. The collateral sensitivity of 402-91/ET to temozolomide provides the rationale to investigate the potential use of methylating agents in MLS patients resistant to trabectedin.

Phase I and pharmacokinetic study of trabectedin 3-hour infusion every three weeks in patients with advanced cancer and alteration of hepatic function

Maximum tolerated dose (MTD), recommended dose (RD), and pharmacokinetics (PK) were evaluated for trabectedin 3-h every-3-weeks schedule in 33 cancer patients stratified according to liver dysfunction degree as per baseline alkaline phosphatase (AP). Stratification was as follows: stratum I [upper limit of normal (ULN) < AP ≤ 1.5 × ULN; n = 16], stratum II [1.5 × ULN < AP ≤ 2.5 × ULN; n = 12], and stratum III [AP >2.5 × ULN; n = 5] (bilirubin <2.5 × ULN for all 3 strata). In each stratum, patients were treated in sequential cohorts at escalating doses. Dose-limiting toxicities (DLTs) were grade 3 transaminase increases not recovering baseline values on day 21, febrile neutropenia/grade 4 neutropenia lasting >5 days and AP increase more than twice over baseline. The MTD and RD for stratum I (mild baseline AP) was 1.3 mg/m(2). Recruitment was stopped early in strata II/III (moderate/severe baseline AP) without reaching the MTD due to slow accrual and difficulty in finding patients. Biochemical parameters other than AP (bilirubin, AST or ALT) were similar between strata. No relevant PK differences were found between strata. In conclusion, the MTD and RD (1.3 mg/m(2)) were confirmed only for stratum I. Stratification criteria based on baseline AP apparently did not segregate the patients according to their liver dysfunction degree. Antitumor activity was found in patients with pretreated ovarian cancer.

Introduction

Ovarian cancer is the second most common gynecological cancer, representing 5% of all cancers in women. It has the highest case-fatality rate of all gynecological malignancies. In the European Union, there are approximately 48,000 new cases of ovarian cancer and 31,000 deaths per year. Similarly, in the United States, there are approximately 25,500 new cases per year, with 16,000 deaths associated.

Trabectedin has a low cardiac risk profile: a comprehensive cardiac safety analysis

PURPOSE

This analysis provides a cross-study evaluation of the cardiac safety of trabectedin.

METHODS

Drug-related cardiac adverse events (CAEs) were retrieved from phase I-III clinical trials, pharmacovigilance databases, and spontaneously reported cases. Left ventricular ejection fraction (LVEF) was monitored in combination phase I studies with doxorubicin or pegylated liposomal doxorubicin (PLD) and in a phase III trial (with PLD).

RESULTS

CAEs [grade 4 cardiac arrest with severe pancytopenia and sepsis (n = 1 patient), grade 4 atrial fibrillation (n = 2), and grade 1 tachycardia (n = 1)] occurred in 4/283 patients (1.4%) in 6 single-agent phase I trials. CAEs (grade 1 sinus tachycardia in a hypertensive patient and grade 1 ventricular dysfunction) occurred in 2/155 patients (1.3%) in 4 phase I combination trials. Results from 19 single-agent phase II trials showed CAEs in 20/1,132 patients (1.8%): arrhythmias (tachycardia/palpitations; n = 13; 1.1%) were the most common. A rather similar rate of symptomatic CAEs was observed in both arms of a phase III trial in recurrent ovarian cancer: 6/330 patients (1.8%; PLD) and 11/333 patients (3.3%; trabectedin/PLD). No clinically relevant LVEF changes occurred in phase I combination trials. In the phase III trial, LVEF decreases from baseline were similar: 9% of patients (PLD) and 7% (trabectedin/PLD), with no relevant symptoms. During postmarketing experience in soft tissue sarcoma (2,046 patients treated), 4 CAEs (2 cardiac arrest, 2 cardiac failure; ~0.2%) occurred in patients with preexisting conditions.

CONCLUSIONS

Trabectedin has a low incidence of CAEs, consisting mainly of arrhythmias. This extensive data review indicates a low cardiac risk profile for trabectedin.

Trabectedin plus pegylated liposomal doxorubicin in relapsed ovarian cancer delays third-line chemotherapy and prolongs the platinum-free interval

BACKGROUND

OVA-301 is a large randomized trial that showed superiority of trabectedin plus pegylated liposomal doxorubicin (PLD; CentoCor Ortho Biotech Products L.P., Raritan, NJ, USA). over single-agent PLD in 672 patients with relapsed ovarian cancer, particularly in the partially platinum-sensitive subgroup [platinum-free interval (PFI) of 6-12 months]. This superiority has been suggested to be due to the differential impact of subsequent (platinum) therapy.

PATIENTS AND METHODS

a detailed analysis of subsequent therapies and survival outcomes in the overall population and in the subsets according to platinum sensitivity was therefore conducted.

RESULTS

similar proportions of patients received subsequent therapy in each arm (76% versus 77%), including further platinum-based regimens (49% versus 55%). Patients in the trabectedin/PLD arm received subsequent chemotherapy at a later time (median delay 2.5 months versus PLD arm). Overall survival from subsequent platinum was significantly prolonged in the partially platinum-sensitive disease subset (hazard ratio = 0.63; P = 0.0357).

CONCLUSION

the superiority of trabectedin/PLD over single-agent PLD in OVA-301 cannot be explained by differences in the extent or nature of subsequent therapies administered to these patients. On the other hand, these exploratory analyses support the hypothesis that the enhanced survival benefits in the partially platinum-sensitive subset might be due to an extended PFI leading to longer survival with subsequent platinum.

Trabectedin plus pegylated liposomal doxorubicin in relapsed ovarian cancer: outcomes in the partially platinum-sensitive (platinum-free interval 6-12 months) subpopulation of OVA-301 phase III randomized trial

BACKGROUND

OVA-301 is a large randomized trial that showed superiority of trabectedin plus pegylated liposomal doxorubicin (PLD) over PLD alone in relapsed ovarian cancer. The optimal management of patients with partially platinum-sensitive relapse [6-12 months platinum-free interval (PFI)] is unclear.

PATIENTS AND METHODS

within OVA-301, we therefore now report on the outcomes for the 214 cases in this subgroup.

RESULTS

Trabectedin/PLD resulted in a 35% risk reduction of disease progression (DP) or death [hazard ratio (HR) = 0.65, 95% confidence interval (CI), 0.45-0.92; P = 0.0152; median progression-free survival (PFS) 7.4 versus 5.5 months], and a significant 41% decrease in the risk of death (HR = 0.59; 95% CI, 0.43-0.82; P = 0.0015; median survival 23.0 versus 17.1 months). The safety of trabectedin/PLD in this subset mimicked that of the overall population. Similar proportions of patients received subsequent therapy in each arm (76% versus 77%), although patients in the trabectedin/PLD arm had a slightly lower proportion of further platinum (49% versus 55%). Importantly, patients in the trabectedin/PLD arm survived significantly longer after subsequent platinum (HR = 0.63; P = 0.0357; median 13.3 versus 9.8 months).

CONCLUSION

This hypothesis-generating analysis demonstrates that superior benefits with trabectedin/PLD in terms of PFS and survival in the overall population appear particularly enhanced in patients with partially sensitive disease (PFI 6-12 months).

New emerging drugs targeting the genomic integrity and replication machinery in ovarian cancer

INTRODUCTION

Ovarian cancer is a difficult to treat cancer entity with a high relapse rate. After initial surgery and chemotherapy, only a few options for therapeutic treatment remain in case of cancer recurrence. New treatment options with improved efficacies to circumvent acquired or pre-existing drug resistance are needed.

MATERIALS

This survey focuses on new prospective drugs for ovarian cancer treatment that either cause direct damage to the nuclear DNA or inhibit chromosome segregation by acting as mitotic spindle inhibitors.

RESULTS

Among a plethora of currently tested and proposed new drugs for ovarian cancer treatment, only a few appear to meet the criteria of sufficient and reliable efficacy with tolerable toxicity. These include the naturally occurring DNA-alkylating alkaloid trabectedin, the nitrogen mustard prodrug canfosfamide, and the synthetic kinase inhibitor ON-01910. The latter inhibits mitotic spindle formation without a direct tubulin interaction, avoiding adverse neurotoxic reactions common to the taxanes. Further, epothilones and oxaliplatin, already approved drugs for other cancer entities, show promising activity against ovarian cancer; they are even of interest as a first-line treatment option.

DISCUSSION

Although the current focus and interest of modern cancer drug design tends to be more specific and targeted therapies, including therapeutic antibodies and specific small molecules to inhibit growth-, apoptosis-, and angiogenesis-regulating signalling cascades, the main target for ovarian cancer treatment appears to remain its basic, though uncontrolled working proliferation machinery. This includes the current gold standard for ovarian cancer chemotherapy, carboplatin, and taxanes, as well as the few remaining alternatives, such as topotecan, doxorubicin, and gemcitabine, which all rely on their ability to bind to or to modify the DNA or the chromosome-separating spindle apparatus. Thus, the genomic integrity and replication machinery of ovarian cancer cells prove to represent an established, and obviously still effective target to be tackled for ovarian cancer treatment.

Emerging drugs for ovarian cancer

IMPORTANCE OF THE FIELD

Ovarian cancer has the highest mortality of all female reproductive tract cancers, which reflects both the absence of proven ovarian cancer screening tests and the development of drug-resistant cancer cell. Apart from varying the dosages, schedules, mode of delivery and combinations of existing drugs, efforts must continue to identify signaling pathways in tumor cells sufficiently different from normal cells that can be a target for maximizing tumor kill and minimizing toxicity.

AREAS COVERED IN THIS REVIEW

Some of the most important cellular pathways are analyzed and discussed and the most interesting clinical trials, both closed and ongoing, described.

WHAT THE READER WILL GAIN

The reader will gain a panoramic vision of all the most active drugs in clinical investigations in ovarian cancer. The reader will also better understand what the unresolved problems of molecular research are and how complicated the process 'from the bench to the bedside' is.

TAKE HOME MESSAGE

It is only with a strong commitment, cooperation and collaboration from the international ovarian cancer community that significant improvement in patient outcomes can be attained beyond the marginal gains achieved so far.

Wide-spectrum characterization of trabectedin: biology, clinical activity and future perspectives

Ecteinascidin-743 (trabectedin, Yondelis®; PharmaMar, Madrid, Spain), a 25-year-old antineoplastic alkylating agent, has recently shown unexpected and interesting mechanisms of action. Trabectedin causes perturbation in the transcription of inducible genes (e.g., the multidrug resistance gene MDR1) and interaction with DNA repair mechanisms (e.g., the nucleotide excision repair pathway) owing to drug-related DNA double strand breaks and adduct formation. Trabectedin was the first antineoplastic agent from a marine source (namely, the Caribbean tunicate Ecteinascidia turbinata) to receive marketing authorization. This article summarizes the mechanisms of action, the complex metabolism, the main toxicities, the preclinical and clinical evidences of its antineoplastic effects in different types of cancer and, finally, the future perspectives of this promising drug.