STRO-002-GM2: A phase 1, open-label, safety, pharmacokinetic, and preliminary efficacy study of STRO-002, an anti-folate receptor alpha (FolRα) antibody-drug conjugate (ADC), in combination with bevacizumab in patients with advanced epithelial ovarian cancer (EOC, including fallopian tube or primary peritoneal cancers)

TPS5622

Background: STRO-002 is a novel FolRα targeting ADC, generated using cell-free antibody production and site-specific conjugation technology. STRO-002 demonstrates potent in vitro cytotoxicity in EOC cell lines and anti-tumor activity in xenograft models, including induction of immunogenic cell death. STRO-002 is currently being studied as a single agent in ovarian and endometrial cancer (Phase 1 Study STRO-002-GM1; NCT03748186). Preliminary efficacy data in relapsed/progressive platinum resistant EOC compared favorably to standard chemotherapy (Naumann W., et al, ASCO 2021). Pre-clinical models tested with STRO-002/bevacizumab combinations demonstrated additive anti-tumor activity compared to monotherapy. This study is a first in human study of STRO-002 plus bevacizumab in patients with advanced ovarian cancer that have progressed on standard therapy. Methods: STRO-002-GM2 is a Phase 1, open-label, multicenter, dose escalation study with a standard 3+3 design with a 21-day dose-limiting toxicity (DLT) assessment period followed by dose expansion. The study will assess safety, establish recommended phase 2 dose (RP2D), and preliminary efficacy of STRO-002/bevacizumab combination in patients with recurrent high-grade EOC. Bevacizumab will be administered at the labeled dose of 15 mg/kg given with STRO-002 starting at 3.5 mg/kg, both administered IV q 3 weeks. Planned dose escalation doses of STRO-002 include 3.5, 4.3, and 5.2 mg/kg and will continue until MTD/MAD is reached. Additional intermediate dose level cohorts may be added for RP2D optimization. Once a cohort is cleared per dose escalation rules, up to 10 additional subjects may be enrolled and treated at that cleared dose level in order to obtain additional safety and efficacy data for RP2D determination and ungating of the expansion stage. Dose expansion will enroll approximately 40 patients treated at the RP2D. The patient population is relapsed high-grade EOC with up to 4 prior regimens. Subjects with primary platinum refractory disease will be enrolled in dose escalation only. Key inclusion criteria include: measurable disease, adequate bone marrow and renal function. Key exclusion criteria include: contraindication to receive bevacizumab and prior treatment with a FolRα ADC or ADC containing a tubulin inhibitor. Efficacy evaluation is per RECIST v1.1. Tumor tissue (archival or fresh biopsy) is required. Study oversight includes a Safety Evaluation Team. Samples will be collected to assess the PK and immunogenicity. No formal statistical hypothesis testing will be conducted in this study. This study is currently open for enrollment in the U.S. Clinical trial information: NCT05200364.

Phase Ia dose-escalation study of the anti-BTLA antibody icatolimab as a monotherapy in patients with advanced solid tumor

2643

Background: The B- and T-lymphocyte attenuator (BTLA) is an inhibitory receptor expressed on B, T and NK cells. Icatolimab (TAB004 or JS004) is a humanized IgG4 monoclonal antibody (mAb) with a hinge mutation (S228P) that binds BTLA and blocks its interaction with its ligand HVEM. In preclinical studies, icatolimab monotherapy suppressed tumor growth in murine tumor models using human BTLA knock-in mice. In this first-in-human dose-escalation study, we report the preliminary safety and efficacy of icatolimab as a single agent in patients with advanced solid tumors. Methods: Eligible patients with advance solid tumors refractory to standard therapies were enrolled in this study. Icatolimab was administered at escalating doses of 0.3, 1, 3 and 10 mg/kg intravenously Q3W and followed by dose expansion in 3 and 10 mg/kg cohorts until disease progression or intolerable toxicity. Dose-limiting toxicity (DLT) was evaluated by a safety monitoring committee. Study objectives included safety, pharmacokinetics, pharmacodynamics, and anti-tumor activity. Results: A total of 25 patients with solid tumor were enrolled in the Part A of this phase I study (NCT04137900). The median age was 62 (range 32-85) years with 16 (64%) male patients. Patients were heavily pretreated with a median of 4 prior lines of therapy. Fifteen (60%) patients received and progressed upon prior anti-PD-1/L1 therapy. By the data cutoff date of December 31, 2021, the median follow-up was 32 weeks. No DLT was observed. 24 (96%) patients experienced treatment emergent adverse event (TEAEs), with 7 (28%) experienced grade 3 TEAEs. No grade 4 or 5 TEAE occurred. The incidence or severity of AE was not associated with the dose. The most common TEAEs were fatigue (32%), abdominal pain (20%), diarrhea (16%), arthralgia (16%), aspartate aminotransferase increased (16%), constipation (16%), and contusion (16%). One (4%) TEAE led to discontinuation of study drug. Four (16%) patients experienced immune related AE. Among 19 evaluable patients by the cutoff date, 1 confirmed PR (melanoma) and 6 SD were observed as assessed by the investigator per RECIST v1.1. The response was still ongoing over 12 months in the melanoma patient who had progressed upon prior nivolumab and BRAF/MEK inhibitors treatments. BTLA receptor was fully occupied in the 3 and 10 mg/kg cohorts. The mean elimination half-life of icatolimab was 7.5 to 19.2 days in four dose cohorts. Biomarker analysis indicated co-expression of HVEM and CD8 was associated with favorable response. Conclusions: Icatolimab monotherapy were well tolerated in all doses evaluated and showed preliminary clinical efficacy as a monotherapy. Icatolimab in combination with toripalimab (anti-PD-1) for the treatment of patients with advanced solid tumors is currently ongoing. Clinical trial information: NCT04137900.

Phase 1 dose-escalation study of STRO-002, an antifolate receptor alpha (FRα) antibody drug conjugate (ADC), in patients with advanced, progressive platinum-resistant/refractory epithelial ovarian cancer (EOC)

5550

Background: STRO-002-GM1 is a Phase 1, open-label study in patients (pts) with advanced, platinum resistant or refractory EOC. STRO-002 is a novel FRα-targeting ADC with a precise DAR of 4 using site-specific conjugation technology to circumvent limitations of current ADCs. STRO-002 induces immunogenic cell death and contains the tubulin-targeting 3-aminophenyl hemiasterlin warhead SC209, a potent cytotoxin that is a weak substrate for P-gp. Methods: STRO-002 is given IV on Day 1 of each 21-day cycle until disease progression. Ocular exams are performed at baseline and every other cycle. Prophylactic corticosteroid eyedrops are not administered. FRα expression was not required for eligibility and retrospective analysis of FRα expression in archival tumor tissue is ongoing. Results: Enrollment has been completed with 39 pts treated at 9 dose levels (0.5 to 6.4 mg/kg). Data cut-off is Jan 30, 2021. Median age was 61 years (range 48-79). Median number of prior systemic therapies was 6 (range 2-11). 86% of treatment emergent adverse events (AEs) were Grade 1-2. The most common treatment related Grade 3 and 4 AEs were reversible neutrophil count decreased (36%) and neutropenia (33%), Grade 3 arthralgia (12.8%) and neuropathy (7.7%). Two pts developed neutropenic fever that resolved with antibiotic therapy. 34 pts were treated at clinically active doses (≥ 2.9 mg/kg) and 31/34 are evaluable for RECIST 1.1 response. Objective responses were seen in 10/31 pts - 1 CR, 4 confirmed PR, and 5 unconfirmed PR (imaging studies under review in 1 pt with uPR). Disease control rate (CR+PR+SD) is 74% at ≥ 12 weeks and 61% at ≥ 16 weeks. 5 pts remain on treatment with 3 ongoing at > 74 weeks. FRα-expression results are available in 14 pts treated at ≥ 2.9 mg/kg with 50% low, 21% medium and 29% high FRα-expressing tumors per PS2+ scoring algorithm. 12/13 pts with H-scores of ≥ 105 achieved disease control with PR or SD. Maximum plasma concentrations of STRO-002 were achieved at the end of the 1 hour infusion and exposure increased in an apparent dose proportionate/linear manner. Conclusions: STRO-002 is a novel FRα-targeting ADC with an encouraging emerging safety and efficacy profile in heavily pretreated relapsed/refractory EOC. No ocular toxicity signals have been observed. Durable responses and anti-tumor activity have been demonstrated across a broad range of FRα expression levels in evaluable pts treated at ≥ 2.9 mg/kg. 48% (15/31) of pts were on treatment without disease progression for ≥ 24 weeks and 13% (4/31) remain on treatment for over a year, suggesting that STRO-002 is well tolerated in long-term responding patients. A randomized expansion cohort comparing STRO-002 at 4.3 mg/kg vs 5.2 mg/kg dose levels in less heavily pretreated EOC pts is ongoing. Clinical trial information: NCT03748186.

Quality of Life in Adult and Pediatric Patients with Tropomyosin Receptor Kinase Fusion Cancer Receiving Larotrectinib

Neurotrophic tyrosine receptor kinase (NTRK) gene fusions lead to chimeric tropomyosin receptor kinase (TRK) fusion proteins, which act as primary oncogenic drivers in diverse tumor types in adults and children. Larotrectinib, a highly selective and central nervous system-active TRK inhibitor, has shown high objective response rates, durable disease control, and a favorable safety profile in patients with TRK fusion cancer. The impact of larotrectinib on health-related quality of life (HRQoL) was evaluated in adult and pediatric patients in two phase I/II clinical trials (NAVIGATE; NCT02576431 and SCOUT; NCT02637687). Patients completed HRQoL questionnaires (EORTC QLQ-C30, EQ-5D-5L, and PedsQL) at baseline and at planned treatment cycle visits. Changes in questionnaire scores were evaluated over time, and by tumor type and treatment response. Questionnaires from 40 adult and 17 pediatric (2-19 years of age) patients receiving larotrectinib were completed at baseline and at least one post-baseline timepoint. Meaningful within-patient HRQoL improvements occurred at one or more timepoints in 60% of adults and 76% of pediatric patients. Sustained improvements in EORTC QLQ-C30 and PedsQL scores were rapid, occurring within 2 months of treatment initiation in 68% and 71% of patients, respectively. Improvements were observed regardless of tumor type and appeared to correlate with clinical efficacy. The rapid within-patient HRQoL improvements in adult and pediatric patients with TRK fusion cancer are consistent with the clinical profile of larotrectinib. Our results provide valuable information for use of this agent in this patient population. A plain language summary of this article is available in the supplementary appendix.

Post hoc analyses of GOG 9923: Does BRCA status affect toxicities?: An NRG oncology study

OBJECTIVE

To evaluate how women with epithelial ovarian cancer (EOC), dichotomized by BRCA status, tolerate intravenous (IV) or intraperitoneal (IP) chemotherapy given with veliparib and bevacizumab (bev) on a GOG phase I study (GOG 9923, NCT00989651).

METHODS

This is an unplanned, post hoc analysis of an IRB approved, multi-institutional, prospective study (GOG 9923). Clinical characteristics and toxicity data based on BRCA status were evaluated and descriptive statistics were used to summarize baseline patient characteristics and toxicities. The Kaplan Meier method was used to generate survival estimates.

RESULTS

Four hundred twenty-four patients were evaluable. Patients were treated with IV carboplatin, paclitaxel, and bev every 21 days (regimen 1), weekly IV paclitaxel with carboplatin and bev (regimen 2) or IV paclitaxel and bev with IP cisplatin (regimen 3). Bev was continued as maintenance in all arms. Within each of these regimens, veliparib was given either twice daily for the entirety of each cycle (continuous) or on days -2 to 5 (intermittent). Ten percent of patients treated on regimen 1, 12% on regimen 2, and 19.8% on regimen 3 had BRCA-associated tumors. Patients with BRCA-associated tumors, when compared to wild type, experienced similar rates of anemia, febrile neutropenia (, abdominal pain, colonic perforation, nausea, vomiting, and peripheral sensory neuropathy. Median progression free survival (PFS) was not significantly different between BRCA-associated and wild type cancers (HR 0.96, CI 0.65-1.42), though this study's primary aim was not to evaluate outcomes.

CONCLUSIONS

Germline BRCA mutations positively affect chemosensitivity in EOC, but whether differences in toxicities among BRCA-associated and BRCA wild type tumors existed was previously not reported. In this population with newly diagnosed ovarian cancer no differences in reported toxicity between the two groups was observed.

Immune Activation in Patients with Locally Advanced Cervical Cancer Treated with Ipilimumab Following Definitive Chemoradiation (GOG-9929)

PURPOSE

A phase I clinical trial (GOG-9929) examined the safety and efficacy of adjuvant immune-modulation therapy with the checkpoint inhibitor ipilimumab [anti-CTL antigen-4 (anti-CTLA-4)] following chemoradiation therapy (CRT) for newly diagnosed node-positive human papillomavirus (HPV)-related cervical cancer. To better understand the mechanism of action and to identify predictive biomarkers, immunologic and viral correlates were assessed before, during, and after treatment.

PATIENTS AND METHODS

Twenty-one patients who received CRT and ≥2 doses of ipilimumab and 5 patients who received CRT only were evaluable for translational endpoints. Circulating T-cell subsets were evaluated by multiparameter flow cytometry. Cytokines were evaluated by multiplex ELISA. HPV-specific T cells were evaluated in a subset of patients by IFNγ ELISpot.

RESULTS

Expression of the activation markers ICOS and PD-1 significantly increased on T-cell subsets following CRT and were sustained or increased following ipilimumab treatment. Combined CRT/ipilimumab treatment resulted in a significant expansion of both central and effector memory T-cell populations. Genotype-specific E6/E7-specific T-cell responses increased post-CRT in 1 of 8 HPV16⁺ patients and in 2 of 3 HPV18⁺ patients. Elevation in levels of tumor-promoting circulating cytokines (TNFα, IL6, IL8) post-CRT was significantly associated with worse progression-free survival.

CONCLUSIONS

Our data indicate that CRT alone and combined with ipilimumab immunotherapy show immune-modulating activity in women with locally advanced cervical cancer and may be a promising therapeutic option for the enhancement of antitumor immune cell function after primary CRT for this population at high risk for recurrence and metastasis. Several key immune biomarkers were identified that were associated with clinical response.

Abstract CT125: STRO-002-GM1, a first in human, phase 1 study of STRO-002, an anti-folate receptor alpha (FRα) antibody drug conjugate (ADC), in patients with advanced platinum-resistant/refractory epithelial ovarian cancer (OC), including fallopian tube or primary peritoneal cancers

Introduction: FRα is overexpressed in 80% of OC with minimal expression in normal tissues. STRO-002 is a novel FRα-targeting ADC designed to circumvent limitations of current ADCs. STRO-002 was generated with a cell-free antibody production system (XpressCF™) and site-specific conjugation (XpressCF+™) platform. STRO-002 has a DAR of 4 and contains the tubulin-targeting 3-aminophenyl hemiasterlin warhead SC209, a potent cytotoxin that is rapidly cleared and a weak substrate for P-gp efflux pumps. STRO-002 demonstrated potent cytotoxic activity in multiple FRα-positive tumor cell lines and significant efficacy in OC xenograft models. Herein we report the results of our dose escalation study of STRO-002 in patients (pts) with OC. Methods: STRO-002-GM1 is a Phase I, open-label, multicenter, dose escalation study with dose expansion to identify the maximum tolerated dose (MTD), and recommended Phase II dose (RP2D) in pts with advanced, platinum resistant or refractory OC. There is no patient selection based on FRα expression. STRO-002 is given IV on Day 1 of each 21-day cycle (C) until disease progression. Ocular exams are performed at baseline and every other cycle. No prophylactic corticosteroid eye drops are used. Results: 20 pts have been dosed & 18 pts have completed at least 1 cycle of STRO-002 at 7 dose levels: 0.5, 1.0, 1.8, 2.9, 4.3, 5.2 and 6.0 mg/kg. Median age is 60.5 (r, 48-70). Median ECOG status is 0 (r, 0-1). Median # of prior therapies is 6 (r, 2-10). 55% of pts have prior PARP inhibitors, 85% have prior bevacizumab. Median # of STRO-002 cycles is 3 (r, 1-15). One DLT of grade 3 neuropathy was reported at the 6.0 mg/kg dose level. Two patients have experienced grade 4 neutropenia, an expected and reversible side effect of STRO-002 treatment. 92% of AEs are grade 1 or 2. The most common TEAEs in ≥ 30 % of pts includes fatigue, nausea, decreased appetite and dizziness. No ocular findings have been observed. Emerging PK profile: after 1 hour infusion, total antibody concentrations declined in a log-linear manner with a 22-84 h half-life, dose-exposure relationship appeared linear without accumulation after repeat administration. Six pts have discontinued due to disease progression. 14 pts remain on treatment and dose escalation is ongoing. One patient has achieved a confirmed partial response (PR); 2 patients have confirmed stable disease (cSD) at C5, 2 pts have cSD at C7 and 1 pt has cSD at C13; 3 patients have achieved a confirmed CA-125 response. Conclusions: STRO-002 is the first hemiasterlin-containing ADC generated with cell-free protein synthesis technology to be tested in pts with solid tumors. The preliminary safety profile and evidence of efficacy and clinical benefit in the first 20 OC pts treated with STRO-002 is encouraging, particularly in this heavily pre-treated, platinum resistant/refractory patient population. No ocular toxicity signals have been observed. MTD has not been reached. Updated results and the recommended phase 2 dose will be presented. This study is registered with clinicaltrials.gov identifier NCT03748186.

Citation Format: R. Wendel Naumann, Denise Uyar, John W. Moroney, Fadi S. Braiteh, Russell J. Schilder, John P. Diaz, Erika Hamilton, Sami Diab, Lainie P. Martin, David M. O'Malley, Richard T. Penson, Clifford DiLea, Michael Palumbo, Venita DeAlmeida, Shannon Matheny, Arturo Molina. STRO-002-GM1, a first in human, phase 1 study of STRO-002, an anti-folate receptor alpha (FRα) antibody drug conjugate (ADC), in patients with advanced platinum-resistant/refractory epithelial ovarian cancer (OC), including fallopian tube or primary peritoneal cancers [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT125.

Abstract LB-133: Correlative analysis of pharmacokinetics and pharmacodynamics of RGX-104, a first-in-class Liver-X-Receptor (LXR) agonist, and clinical outcomes in patients with advanced solid tumors

RGX-104, a first-in-class small-molecule LXR agonist modulates innate immunity and cancer progression via transcriptional activation of ApoE. ApoE protein suppresses tumor cell invasion and angiogenesis, and also depletes circulating and tumoral myeloid derived suppressor cells (MDSC), leading to T cell activation.A multivariate approach was used to address pharmacokinetic (PK) and pharmacodynamic relationships of RGX-104 in a phase 1 dose escalation study in patients with relapsed/refractory solid tumors. The study entailed multiple escalation arms with RGX-104 as monotherapy and in combination with nivolumab, ipilimumab, or docetaxel. Various markers including intratumoral ApoE and its receptor LRP1 in biopsy specimens, gene expression of LXR-targets in whole blood, serum markers including cytokines and lipids, as well as immune cell types such as MDSC, CD8 T-cells, and neutrophils in peripheral blood from patients were monitored at several time points. PK metrics were tracked to assess dose response relationships. Clinical outcomes such as objective response, time to disease progression, and duration on therapy were used for exploratory correlative analyses. A generally dose dependent increase in steady state exposure to RGX-104 was observed among all cohorts; the lowest efficacious exposure among patients with partial response was ~14,000 ng*h/mL. Treatment with RGX-104 at doses ranging from 120 mg BID to 240 mg BID induced expression of LXR targets, ApoE [2.7X (p=0.008) to 7.1X (p=0.007)] and ABCA1 [ 6.3X (p=1.20E-03) to 7X (p=8.1E-04] over baseline in a generally dose-dependent manner as assessed in whole blood. Similarly, MDSC depletion, ranging from 70%-90% relative to baseline, was observed in patients treated with RGX-104 along with concomitant CD8 T-cell activation; similar effects were noted in patients in combination cohorts. A model to explore dose dependency of change in immune cell types suggested that baseline levels of MDSC were most predictive of the magnitude of MDSC reduction after treatment, and that favorable clinical outcomes correlate with the extent of MDSC reduction and T cell activation. Low baseline levels of tumoral ApoE were associated with greater clinical benefit, with almost all patients with stable disease or partial response exhibiting ApoE tumor positive score of ≤20%; these patients also exhibited low/negative PD-L1 (<1%) staining, revealing a target specific tumor biomarker and PD-L1 subset that could support prospective patient selection. These and additional markers will be tracked in expansion cohorts of RGX-104 in combination with pembrolizumab and carboplatin/pemetrexed for 1st line treatment of patients with metastatic non-small cell lung cancer (PD-L1 <1%) and in combination with docetaxel for 2nd line treatment of patients with small cell lung cancer.

Citation Format: Monica Mita, Alan Mita, Erika Hamilton, Gerald S. Falchook, Michael Postow, Bartosz Chmielowski, Russell J. Schilder, James Strauss, Emerson Lim, Shubham Pant, Angela Jain, Oliver Rixe, Rebecca Redman, Kevin B. Kim, Tomislav Dragovich, R. Donald Harvey, Igor Puzanov, Nimisha Schneider, Renee Deehan, Tobi Guennel, Joe Lin, Sohail Tavazoie, Roger Waltzman, Eric Rowinsky, Michael Szarek, Subhasree Sridhar, Robert Busby, Narayan Lebaka, Celia Andreu, Isabel Kurth, David Darst, Masoud Tavazoie, Syed Raza, Robert Wasserman, Foster C. Gonsalves. Correlative analysis of pharmacokinetics and pharmacodynamics of RGX-104, a first-in-class Liver-X-Receptor (LXR) agonist, and clinical outcomes in patients with advanced solid tumors [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-133.

Abstract CT146: RGX-104, a first-in-class immunotherapy targeting the liver-X receptor (LXR): Initial results from the phase 1b RGX-104 plus docetaxel combination dose escalation cohorts

Background: RGX-104 is a small-molecule LXR agonist that modulates innate immunity via transcriptional activation of the ApoE gene. Binding of ApoE to its receptor LRP8 robustly inhibits angiogenesis and depletes myeloid derived suppressor cells (MDSC), thereby activating cytotoxic T-lymphocytes. MDSCs are associated with resistance to both checkpoint inhibitors (CPI) and chemotherapy, providing a rationale for combination therapy with RGX-104. We previously reported results of the RGX-104 monotherapy dose escalation for which 26 patients with refractory solid tumors were treated in 5 dose cohorts. On-target AEs included hyperlipidemia and neutropenia. Flow-cytometry demonstrated MDSC depletion with associated T cell activation, which correlated with clinical benefit. A 40% disease control rate (DCR; SD+PR) was observed with a confirmed partial response (PR) by irRC (>79% reduction in index lesions) in a patient with platinum-refractory small cell lung cancer (SCLC). Methods: Here, we present the safety, biomarker and efficacy results of the docetaxel combination arm of the RGX-104 trial. Cohort 1- RGX-104 80 mg BID, and docetaxel at 35 mg/m2 days 1, 8, and 15 of a 28-day cycle; Cohort 2- RGX-104 80 mg BID, 5 days-on/2 days-off (5/2), and docetaxel at 28 mg/m2 on above schedule. Cohort 3- RGX-104 100 mg BID (5/2), and docetaxel as per cohort 2. Results: As of February 7, 2020, 11 patients with refractory solid tumors have been treated in 3 dose escalation cohorts with RGX-104 plus docetaxel. AEs were consistent with the individual toxicity profiles of docetaxel and RGX-104, with neutropenia being the most common AE and dose-limiting in cohort 1. The 5/2 dosing regimen in cohorts 2 and 3 resulted in significantly fewer episodes of neutropenia and no DLTs, while maintaining pharmacodynamic effects including >50% sustained MDSC depletion. A 66% DCR was observed in 9 evaluable patients including 2 patients in cohort 2 with PRs, a CPI-refractory SCCHN patient and a CPI-refractory melanoma patient, who remains on treatment at 36 weeks. A patient with melanoma in Cohort 3 had an initial assessment of SD and continues on study at 14 weeks. Clinical responses were associated with increases in T cell activation markers exceeding that generally observed with RGX-104 alone (up to a 5-fold increase in total CD8 T cells, a 7-fold increase in LAG-3+ CD8 T cells, and a 75-fold induction of serum IFNγ). Conclusion: The safety profile and marked pharmacodynamic and clinical activity of the RGX-104/docetaxel combination in CPI-refractory patients supports further development of this regimen. Consequently, the RGX-104/docetaxel regimen will be evaluated in a Phase 1b/2 expansion cohort in patients with relapsed/refractory ES-SCLC/high grade-neuroendocrine tumors.

Citation Format: Emerson Lim, Erika P. Hamilton, Rebecca Redman, Michael A. Postow, Russell J. Schilder, Monica M. Mita, Alain C. Mita, Bartosz Chmielowski, James Strauss, Angela Jain, Shubham Pant, Olivier Rixe, Tomislav Dragovich, R. Donald Harvey, Igor Puzanov, Kevin B. Kim, Eric K. Rowinsky, Michael Szarek, Foster Gonsalves, Isabel Kurth, Celia Andreu, Robert W. Busby, David Darst, Masoud Tavazoie, Syed Raza, Narayan Lebaka16, Robert Wasserman, Gerald Falchook. RGX-104, a first-in-class immunotherapy targeting the liver-X receptor (LXR): Initial results from the phase 1b RGX-104 plus docetaxel combination dose escalation cohorts [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT146.

Berzosertib plus gemcitabine versus gemcitabine alone in platinum-resistant high-grade serous ovarian cancer: a multicentre, open-label, randomised, phase 2 trial

BACKGROUND

High-grade serous ovarian cancers show increased replication stress, rendering cells vulnerable to ATR inhibition because of near universal loss of the G1/S checkpoint (through deleterious TP53 mutations), premature S phase entry (due to CCNE1 amplification, RB1 loss, or CDKN2A mRNA downregulation), alterations of homologous recombination repair genes, and expression of oncogenic drivers (through MYC amplification and other mechanisms). We hypothesised that the combination of the selective ATR inhibitor, berzosertib, and gemcitabine could show acceptable toxicity and superior efficacy to gemcitabine alone in high-grade serous ovarian cancer.

METHODS

In this multicentre, open-label, randomised, phase 2 study, 11 different centres in the US Experimental Therapeutics Clinical Trials Network enrolled women (aged ≥18 years) with recurrent, platinum-resistant high-grade serous ovarian cancer (determined histologically) and Eastern Cooperative Oncology Group performance status of 0 or 1, who had unlimited previous lines of cytotoxic therapy in the platinum-sensitive setting but no more than one line of cytotoxic therapy in the platinum-resistant setting. Eligible patients were randomly assigned (1:1) to receive intravenous gemcitabine (1000 mg/m²) on day 1 and day 8, or gemcitabine plus intravenous berzosertib (210 mg/m²) on day 2 and day 9 of a 21-day cycle until disease progression or intolerable toxicity. Randomisation was done centrally using the Theradex Interactive Web Response System, stratified by platinum-free interval, and with a permuted block size of six. Following central randomisation, patients and investigators were not masked to treatment assignment. The primary endpoint was investigator-assessed progression-free survival, and analyses included all patients who received at least one dose of the study drugs. The study is registered with ClinicalTrials.gov, NCT02595892, and is active but closed to enrolment.

FINDINGS

Between Feb 14, 2017, and Sept 7, 2018, 88 patients were assessed for eligibility, of whom 70 were randomly assigned to treatment with gemcitabine alone (36 patients) or gemcitabine plus berzosertib (34 patients). At the data cutoff date (Feb 21, 2020), the median follow-up was 53·2 weeks (25·6-81·8) in the gemcitabine plus berzosertib group and 43·0 weeks (IQR 23·2-69·1) in the gemcitabine alone group. Median progression-free survival was 22·9 weeks (17·9-72·0) for gemcitabine plus berzosertib and 14·7 weeks (90% CI 9·7-36·7) for gemcitabine alone (hazard ratio 0·57, 90% CI 0·33-0·98; one-sided log-rank test p=0·044). The most common treatment-related grade 3 or 4 adverse events were decreased neutrophil count (14 [39%] of 36 patients in the gemcitabine alone group vs 16 [47%] of 34 patients in the gemcitabine plus berzosertib group) and decreased platelet count (two [6%] vs eight [24%]). Serious adverse events were observed in ten (28%) patients in the gemcitabine alone group and nine (26%) patients in the gemcitabine plus berzosertib group. There was one treatment-related death in the gemcitabine alone group due to sepsis and one treatment-related death in the gemcitabine plus berzosertib group due to pneumonitis.

INTERPRETATION

To our knowledge, this is the first randomised study of an ATR inhibitor in any tumour type. This study shows a benefit of adding berzosertib to gemcitabine in platinum-resistant high-grade serous ovarian cancer. This combination warrants further investigation in this setting.

FUNDING

US National Cancer Institute.

Larotrectinib in patients with TRK fusion-positive solid tumours: a pooled analysis of three phase 1/2 clinical trials

BACKGROUND

The selective TRK inhibitor larotrectinib was approved for paediatric and adult patients with advanced TRK fusion-positive solid tumours based on a primary analysis set of 55 patients. The aim of our analysis was to explore the efficacy and long-term safety of larotrectinib in a larger population of patients with TRK fusion-positive solid tumours.

METHODS

Patients were enrolled and treated in a phase 1 adult, a phase 1/2 paediatric, or a phase 2 adolescent and adult trial. Some eligibility criteria differed between these studies. For this pooled analysis, eligible patients were aged 1 month or older, with a locally advanced or metastatic non-CNS primary, TRK fusion-positive solid tumour, who had received standard therapy previously if available. This analysis set includes the 55 patients on which approval of larotrectinib was based. Larotrectinib was administered orally (capsule or liquid formulation), on a continuous 28-day schedule, to adults mostly at a dose of 100 mg twice daily, and to paediatric patients mostly at a dose of 100 mg/m² (maximum of 100 mg) twice daily. The primary endpoint was objective response as assessed by local investigators in an intention-to-treat analysis. Contributing trials are registered with ClinicalTrials.gov, NCT02122913 (active not recruiting), NCT02637687 (recruiting), and NCT02576431 (recruiting).

FINDINGS

Between May 1, 2014, and Feb 19, 2019, 159 patients with TRK fusion-positive cancer were enrolled and treated with larotrectinib. Ages ranged from less than 1 month to 84 years. The proportion of patients with an objective response according to investigator assessment was 121 (79%, 95% CI 72-85) of 153 evaluable patients, with 24 (16%) having complete responses. In a safety population of 260 patients treated regardless of TRK fusion status, the most common grade 3 or 4 larotrectinib-related adverse events were increased alanine aminotransferase (eight [3%] of 260 patients), anaemia (six, 2%), and decreased neutrophil count (five [2%]). The most common larotrectinib-related serious adverse events were increased alanine aminotransferase (two [<1%] of 260 patients), increased aspartate aminotransferase (two [<1%]), and nausea (two [<1%]). No treatment-related deaths occurred.

INTERPRETATION

These data confirm that TRK fusions define a unique molecular subgroup of advanced solid tumours for which larotrectinib is highly active. Safety data indicate that long-term administration of larotrectinib is feasible.

FUNDING

Bayer and Loxo Oncology.

Safety, Tolerability, and Potential Clinical Activity of a Glucocorticoid-Induced TNF Receptor-Related Protein Agonist Alone or in Combination With Nivolumab for Patients With Advanced Solid Tumors: A Phase 1/2a Dose-Escalation and Cohort-Expansion Clinical Trial

Importance

Multiple immunostimulatory agonist antibodies have been clinically tested in solid tumors to evaluate the role of targeting glucocorticoid-induced tumor necrosis factor (TNF) receptor-related protein in anticancer treatments.

Objective

To evaluate the safety and activity of the fully human glucocorticoid-induced TNF receptor-related protein agonist IgG1 monoclonal antibody BMS-986156 with or without nivolumab in patients with advanced solid tumors.

Design, Setting, and Participants

This global, open-label, phase 1/2a study of BMS-986156 with or without nivolumab enrolled 292 patients 18 years or older with advanced solid tumors and an Eastern Cooperative Oncology Group performance status of 1 or less. Prior checkpoint inhibitor therapy was allowed. Monotherapy and combination dose-escalation cohorts ran concurrently to guide expansion doses beginning October 16, 2015; the study is ongoing.

Interventions

The protein agonist BMS-986156 was administered intravenously at a dose of 10, 30, 100, 240, or 800 mg every 2 weeks as monotherapy, and in the combination group 30, 100, 240, or 800 mg plus 240 mg of nivolumab every 2 weeks; same-dose cohorts were pooled for analysis. One cohort also received 480 mg of BMS-986156 plus 480 mg of nivolumab every 4 weeks.

Main Outcomes and Measures

The primary end points were safety, tolerability, and dose-limiting toxic effects. Additional end points included antitumor activity per Response Evaluation Criteria in Solid Tumors, version 1.1, and exploratory biomarker analyses.

Results

With a follow-up range of 1.4 to 101.7 weeks (follow-up ongoing), 34 patients (16 women and 18 men; median age, 56.6 years [range, 28-75 years]) received monotherapy (4 patients completed initial treatment), and 258 patients (140 women and 118 men; median age, 60 years [range, 21-87 years]) received combination therapy (65 patients completed initial treatment). No grade 3 to 5 treatment-related adverse events occurred with BMS-986156 monotherapy; grade 3 to 4 treatment-related adverse events occurred in 24 patients (9.3%) receiving BMS-986156 plus nivolumab, with no grade 5 treatment-related adverse events. One dose-limiting toxic effect (grade 4 elevated creatine phosphokinase levels) occurred in a patient receiving 800 mg of BMS-986156 plus 240 mg of nivolumab every 2 weeks; BMS-986156 with or without nivolumab exhibited linear pharmacokinetics with dose-related increase after a single dose. Peripheral T-cell and natural killer-cell proliferation increased after administration of BMS-986156 with or without nivolumab. No consistent and significant modulation of intratumoral CD8+ T cells and FoxP3+ regulatory T cells was observed. No responses were seen with BMS-986156 alone; objective response rates ranged from 0% to 11.1% (1 of 9) across combination therapy cohorts, with a few responses observed in patients previously treated with anti-programmed death receptor (ligand) 1 therapy.

Conclusions and Relevance

Based on this cohort, BMS-986156 appears to have had a manageable safety profile, and BMS-986156 plus nivolumab demonstrated safety and efficacy comparable to historical data reported for nivolumab monotherapy.

Trial Registration

ClinicalTrials.gov identifier: NCT02598960.

Sequential Ipilimumab After Chemoradiotherapy in Curative-Intent Treatment of Patients With Node-Positive Cervical Cancer

Importance

Despite standard chemoradiotherapy (CRT), most women with lymph node (LN)-positive cervical cancer experience disease recurrence. Immunotherapy is being investigated in the up-front treatment setting.

Objectives

To assess the safety of sequential immunotherapy after CRT and to investigate human papillomavirus (HPV) genotype and HLA allele status on survival and programmed cell death 1 (PD-1) expression before and after CRT and sequential immunotherapy.

Design, Setting, and Participants

This prospective phase 1 trial conducted in 29 Gynecology Oncology Cooperative Group member institutions enrolled participants from December 18, 2012, to August 31, 2016, with a 14.8-month median follow-up and translational end points. Thirty-four women with International Federation of Gynecology and Obstetrics stage IB2 to IVA cervical cancer with positive pelvic LNs, para-aortic LNs, or both were enrolled; 13 did not receive ipilimumab and were excluded from the analysis. Data were analyzed from January 21 to April 4, 2018.

Interventions

Treatment consisted of 6 weekly doses of cisplatin, 40 mg/m2, concurrent with radiotherapy. After completion of chemotherapy, sequential ipilimumab was given every 21 days for 4 doses. Two dosage levels of ipilimumab, 3 mg/kg and 10 mg/kg, were studied to identify the maximum tolerated dose.

Main Outcomes and Measures

The primary end point was safety, and the secondary end points were overall survival and progression-free survival. Exploratory end points included HPV genotype, HLA allele status, and PD-1 expression measured in peripheral blood.

Results

The median age of the 32 participants included in the intent-to-treat analysis was 50 (range, 26-61) years, and 22 patients (69%) were white. Of the 21 patients who received ipilimumab, all had positive pelvic LN, and 6 (29%) had positive para-aortic LNs. All patients completed CRT, and of the 21 patients who received at least 2 cycles of ipilimumab, 18 (86%) completed 4 cycles of ipilimumab, and 3 (14%) completed 2 cycles. The maximum tolerated dose was 10 mg/kg. Two of the 21 patients (9.5%) who received ipilimumab had self-limiting grade 3 toxic effects (lipase increase; dermatitis). The 12-month overall survival was 90%, and progression-free survival was 81%. Human papillomavirus genotype and HLA subtype were not associated with progression-free survival or overall survival. T cells expressing PD-1 increased after CRT, and levels were sustained with ipilimumab.

Conclusions and Relevance

This study's findings suggest that the use of immunotherapy after CRT for curative-intent treatment of patients with cervical cancer is tolerable and effective. The results indicated that PD-1 was upregulated after CRT and sustained with sequential ipilimumab therapy. These immune findings may help guide future therapies to harness the activated T-cell phenotype in patients with node-positive cervical cancer.

A phase I study of intravenous or intraperitoneal platinum based chemotherapy in combination with veliparib and bevacizumab in newly diagnosed ovarian, primary peritoneal and fallopian tube cancer

BACKGROUND

Improvements in disease free survival for epithelial ovarian, peritoneal or fallopian tube cancer (EOC) will only come with improved primary therapy. Incorporation of poly-ADP-ribose inhibitors (PARPi) in the frontline setting may represent one strategy. This study sought to determine the maximum tolerated and feasible doses of the PARPi veliparib in combination with chemotherapy for EOC.

METHODS

A phase I, 3 + 3 dose escalation evaluated dose-limiting toxicities (DLTs) in cycles 1-2. Once <2/6 patients experienced a DLT, that dose level expanded to evaluate feasibility over 4 cycles. This study opened 10/2009 and closed 8/2016. Eligible patients had untreated, stage II-IV EOC. Veliparib was added either continuous (day 1-21) or intermittent (day - 2 to 5) during 6 cycles of chemotherapy. Three chemotherapy backbones were evaluated (2 intravenous (q3week and weekly) and 1 intraperitoneal (IP)) all inclusive of bevacizumab with and as maintenance to 22 cycles.

FINDINGS

Dose evaluations for 424 treated patients were available. Regimen 1 (q3 week), continuous (Reg1c) the maximum tolerated dose (MTD) was 250 mg veliparib BID and feasible dose was 150 mg BID. For regimen 1, intermittent (Reg1i) the MTD and feasible dose were 400 and 250 mg BID. For Reg2c (weekly paclitaxel) the MTD and feasible dose were 150 mg BID. For Reg2i the MTD and feasible dose were 250 and 150 mg BID. For Reg3c (IP) the MTD and feasible dose were 150 mg BID and for Reg3i (IP), the MTD and feasible dose were 400 mg and 300 mg BID.

INTERPRETATION

The feasible dose for Reg1c, 2c, 2i and 3c was 150 mg po BID. For Reg1i and 3i the dose was pushed to 250 and 300 mg po BID respectively. There is no apparent difference in efficacy between continuous and intermittent dosing indicating that the higher doses achieved in intermittent dosing may not be needed. (NCT00989651).

FUNDING

National Cancer Institute.

Safety lead-in of the MEK inhibitor trametinib in combination with GSK2141795, an AKT inhibitor, in patients with recurrent endometrial cancer: An NRG Oncology/GOG study

OBJECTIVE

We sought to determine safety and efficacy of the AKT inhibitor, GSK2141795, combined with the MEK inhibitor, trametinib, in endometrial cancer.

METHODS

Patients with measurable recurrent endometrial cancer were eligible. One to two prior cytotoxic regimens were allowed; prior use of a MEK or PI3K pathway inhibitor was excluded. Initial trial design consisted of a KRAS mutation stratified randomized phase II with a safety lead-in evaluating the combination. For the safety lead in, the previously recommended phase 2 dose (RP2D; trametinib 1.5 mg, GSK2141795 50 mg) was chosen for Dose Level 1 (DL1).

RESULTS

Of 26 enrolled patients, 14 were treated on DL1 and 12 were treated on DL-1 (trametinib 1.5 mg, GSK2141795 25 mg). Most common histologies were endometrioid (58%) and serous (27%). Four of 25 (16%) patients were KRAS mutant. Dose limiting toxicities (DLTs) were assessed during cycle 1. DL1 had 8 DLTs (hypertension (n = 2), mucositis (2), rash (2), dehydration, stroke/acute kidney injury). DL1 was deemed non-tolerable so DL-1 was explored. DL-1 had no DLTs. Sixty-five percent of patients had ≥ grade 3 toxicity. There were no responses in DL1 (0%, 90%CI 0-15%) and 1 response in DL-1 (8.3%, 90%CI 0.4-33.9%). Proportion PFS at 6 months for DL1 is 14%, and 25% for DL-1.

CONCLUSION

The combination of trametinib and GSK2141795 had high levels of toxicity in endometrial cancer at the previously RP2D but was tolerable at a reduced dose. Due to insufficient preliminary efficacy at a tolerable dose, the Phase II study was not initiated.

A phase I study of veliparib incorporated into front-line platinum based cheotherpy and bevacizumab in epithelial ovarian cancer (NCT00989651): A GOG/nrg trial

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Background: Veliparib, a poly-(ADP-ribose)-polymerase inhibitor, increases anti-tumor activity when combined with platinum chemotherapy and has monotherapy activity in BRCA deficient tumors. This study was done to determine the recommended phase II dose (RP2D) of veliparib in combination with front line treatment for epithelial ovarian cancer (EOC). Methods: Eligible patients had newly diagnosed, stage II-IV EOC. Six regimens were evaluated, 3 variations of chemo delivery with either continuous (D1-21) or intermittent (days-2-5) veliparib BID. Chemo included 1: IV q3week carboplatin (C) (AUC 6) and paclitaxel(T) (175mg/m2); 2, IV q3week C (AUC 6) and weekly T(80mg/m2); and 3, IV T (135mg/m2, day 1), IP cisplatin (75mg/m2, day 1 or 2) and IP T (60mg/m2, day 8). Bevacizumab 15mg/kg started cycle 2 and continued as monotherapy cycles 7-22. A 3+3 dose escalation design evaluated dose-limiting toxicities (DLTs) in cycles 1 and 2. Once < 2/6 patients experienced a DLT, that dose level was expanded to evaluate feasibility over 4 cycles. Results: The study accrued 424 treated patients. For regimen 1, continuous (Reg1c) the maximum tolerated dose (MTD) was 250mg veliparib BID but the feasible dose was found to be 150mg BID. For regimen 1, intermittent (Reg1i) the MTD and feasible dose were 400 and 250mg BID respectively. For Reg2c the MTD and feasible dose were the same at 150mg BID. For Reg2i the MTD and feasible dose were 250 and 150mg BID respectively. For Reg3c the MTD and feasible dose are both 150mg BID and for Reg3i, the MTD was 400mg BID and the feasible dose felt to be 300mg BID. Median PFS by residual disease and BRCA status is: (Positive residual disease) 14.6, 19.1 and 16.9 months for BRCA+, BRCAwt and BRCA ukn respectively. For no gross residual disease the PFS is NR, 34.2 and 24.5 months respectively. Conclusions: Given the difficulty with toxicity not defined as a DLT, the RP2D for all regimens is veliparib 150mg BID. This data informed the dose that moved into the phase III trial GOG 3005/Velia: NCT02470585. Velia also incorporated maintenance veliparib instead of maintenance bevacizumab among all high grade serous patients (BRCA+ and wt). These results will determine utilization of veliparib in this space. Clinical trial information: NCT00989651.

Larotrectinib efficacy and safety in adult TRK fusion cancer patients

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Background: A broad range of pediatric and adult malignancies harbor TRK fusions involving the NTRK1, NTRK2, and NTRK3 genes. The highly-selective TRK inhibitor, larotrectinib, has previously shown a high overall response rate (ORR) and a favorable safety profile in patients (pts) with TRK fusion cancer. To better delineate efficacy in adults, as pediatric pts have a particularly high ORR, here we report updated efficacy and safety data from the adult subset of pts with TRK fusion cancer treated with larotrectinib. Methods: Adult pts (aged 18 or older) with TRK fusion cancer detected by local testing in 2 larotrectinib clinical trials (NCT02122913 and NCT02576431) were analyzed. Larotrectinib was administered 100 mg PO BID until disease progression, withdrawal, or unacceptable toxicity. Disease status was assessed by both investigator (INV) and independent assessment (IRC) using RECIST v1.1. Results: As of July 30, 2018, 83 adults (median age: 57 y, range 20–80 y) with TRK fusion cancer had been treated. Cancer types included salivary gland (23%) and thyroid cancer (19%), soft tissue sarcoma (14%), lung cancer (13%), colon cancer and melanoma (7% each), GIST (5%), and bone sarcoma, cholangiocarcinoma, and appendiceal, breast, and pancreas cancer (≤2% each). TRK fusions involved NTRK1 (40%), NTRK2 (2%), and NTRK3 (57%). 77% of pts had received prior systemic therapy (median lines: 2, range 0–10). In 74 pts evaluable per INV, the ORR was 76% with 9% CR, 57% confirmed PR, 9% PR pending confirmation, 12% SD, 11% PD, and 1% not determined; 9 pts were non-evaluable (NE) due to lack of post-baseline assessment. In 65 pts evaluable per IRC, the ORR was 68% with 17% CR, 51% PR, 15% SD, 12% PD, and 5% NE. With a median follow up of 17.2 and 17.5 mo per INV and IRC, respectively, the median duration of response had not been reached (ranges identical: 1.9+ to 38.7+ months). At data cutoff, 63% remained on treatment; 30% had discontinued due to disease progression. Adverse events were mostly grade 1–2. Conclusions: Larotrectinib demonstrated robust tumor-agnostic efficacy and a favorable safety profile in adult pts with TRK fusion cancer. These results support testing for TRK fusion cancer in pts with advanced solid tumors, regardless of site of primary diagnosis. Clinical trial information: NCT02122913 and NCT02576431.

Determination of the recommended phase II dose of birinapant in combination with pembrolizumab: Results from the dose-escalation phase of BPT-201

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Background: Birinapant is a bivalent SMAC mimetic targeting cIAP1. Synergistic effects of combining birinapant with immune checkpoint inhibitors have been demonstrated in preclinical models. Based on these observations, a clinical trial with birinapant and pembrolizumab was initiated (NCT02587962). Methods: Patients ≥18 years with advanced solid tumors without further suitable standard therapeutic options were eligible for inclusion. Birinapant (5.6-22 mg/m2) was administered IV on day 1 and 8 in addition to pembrolizumab 200 mg on day 1 in a 21-day cycle until disease progression using standard 3+3 dose-escalation. The primary objective was to determine the safety and tolerability of the recommended phase 2 dose (RP2D) of birinapant in combination with pembrolizumab. Secondary and exploratory objectives included antitumor activity assessed by RECIST 1.1 and iRECIST, pharmacokinetics and assessment of biomarkers including serum cytokines, cIAP1, PD-L1 expression and tumor infiltrating lymphocytes. Results: Nineteen patients were enrolled at 4 dose levels of 5.6 (n = 3), 11 (n = 3), 17 (n = 6) and 22 (n = 7) mg/m2. Most common tumors were pancreatic (n = 5), colorectal (n = 4), ovarian (n = 3) and sarcoma (n = 3). Median prior therapies were 4 (0-12). The most common AE related to any of the study drugs was rash occurring in 3 patients. Ten patients had 17 SAE's of which only one (stomatitis) was judged related to birinapant. Increased ALT/AST (G3/G2) leading to missed day 8 dose constituted a DLT at 22 mg/m2. Grade 2 lipase increases were seen in 2 patients. No cases of Bell’s palsy were detected. ORR by RECIST 1.1 was 5.6% (n = 1) in 18 evaluable patients. The responding patient had microsatellite stable colorectal carcinoma (MSS-CRC)) and remains on therapy 13+ months after first dose. By iRECIST, ORR was 11.1%. CBR (PR+SD) by RECIST was 22.2%. The exposure to birinapant generally increased with dose. The RP2D was determined to be 22 mg/m2. Conclusions: Birinapant and pembrolizumab is a safe and tolerable combination that has shown encouraging signals of efficacy. A phase 2 study evaluating efficacy of this combination in MSS-CRC is ongoing. Clinical trial information: NCT02587962.

Alisertib in Combination With Weekly Paclitaxel in Patients With Advanced Breast Cancer or Recurrent Ovarian Cancer: A Randomized Clinical Trial

Importance

There is an unmet medical need for the treatment of recurrent ovarian cancer, and new approaches are needed to improve progression-free survival (PFS) and overall survival.

Objective

This phase 1/2 study evaluated the activity of alisertib in combination with weekly paclitaxel in patients with breast (phase 1) and ovarian cancer (phase 1 and phase 2).

Design, Setting, and Participants

An open-label phase 1 and randomized phase 2 clinical trial conducted from April 16, 2010, for phase 1 and March 28, 2012, to August 12, 2013, for phase 2 was conducted at 33 sites (United States, France, and Poland). Data are reported from a cutoff date of August 12, 2014, with a median duration of follow-up of 7.2 months in the alisertib plus paclitaxel arm and 4.6 months in the paclitaxel arm. A total of 191 women with advanced breast (phase 1 only) or recurrent ovarian cancer were enrolled, including 142 patients randomized to alisertib plus paclitaxel (n = 73) or paclitaxel alone (n = 69) in the phase 2 study.

Interventions

Patients were randomized 1:1 stratified by platinum-free interval (refractory, 0-6 months, 6-12 months) and prior weekly taxane treatment (yes, no) to receive alisertib 40 mg twice per day orally and 3 days on and 4 days off for 3 weeks, plus paclitaxel (60 mg/m2 intravenously, days 1, 8, and 15), or weekly paclitaxel 80 mg/m2 intravenously in 28-day cycles.

Main Outcomes and Measures

Primary endpoint was PFS; primary efficacy analysis and safety analysis used modified intention to treat (mITT) population (all randomized patients who received ≥1 dose of study drug).

Results

The median age for the 191 patients enrolled in phase 1 was 59 (range, 29-75) years. The median age for the 142 patients enrolled in phase 2 was 63 (range, 30-81) years for patients receiving alisertib plus paclitaxel and 61 (range, 41-81) years for patients receiving paclitaxel. At data cutoff, 107 (75%) patients had a documented PFS event; 52 (71%) in the alisertib plus paclitaxel arm, and 55 (80%) in the paclitaxel arm. Median PFS was 6.7 months with alisertib plus paclitaxel vs 4.7 months with paclitaxel (HR, 0.75; 80% CI, 0.58-0.96; P = .14; 2-sided P value cutoff = .20 to be considered worthy of further investigation). Drug-related grade 3 or higher adverse events were reported in 63 (86%) vs 14 (20%) patients in the alisertib plus paclitaxel and paclitaxel arms, including 56 (77%) vs 7 (10%) neutropenia, 18 (25%) vs 0 stomatitis, and 10 (14%) vs 2 (3%) anemia; 54 (74%) vs 17 (25%) had adverse events leading to dose reductions. Two patients died during the study (1 in each arm); neither death was considered related to study drug.

Conclusions and Relevance

The primary endpoint, PFS, significantly favored alisertib plus paclitaxel over paclitaxel alone. Further investigation is warranted.

Trial Registration

ClinicalTrials.gov identifier: NCT01091428.

Metformin as a Therapeutic Target in Endometrial Cancers

Endometrial cancer is the most common gynecologic malignancy in developed countries. Its increasing incidence is thought to be related in part to the rise of metabolic syndrome, which has been shown to be a risk factor for the development of hyperestrogenic and hyperinsulinemic states. This has consequently lead to an increase in other hormone-responsive cancers as well e.g., breast and ovarian cancer. The correlation between obesity, hyperglycemia, and endometrial cancer has highlighted the important role of metabolism in cancer establishment and persistence. Tumor-mediated reprogramming of the microenvironment and macroenvironment can range from induction of cytokines and growth factors to stimulation of surrounding stromal cells to produce energy-rich catabolites, fueling the growth, and survival of cancer cells. Such mechanisms raise the prospect of the metabolic microenvironment itself as a viable target for treatment of malignancies. Metformin is a biguanide drug that is a first-line treatment for type 2 diabetes that has beneficial effects on various markers of the metabolic syndrome. Many studies suggest that metformin shows potential as an adjuvant treatment for uterine and other cancers. Here, we review the evidence for metformin as a treatment for cancers of the endometrium. We discuss the available clinical data and the molecular mechanisms by which it may exert its effects, with a focus on how it may alter the tumor microenvironment. The pleiotropic effects of metformin on cellular energy production and usage as well as intercellular and hormone-based interactions make it a promising candidate for reprogramming of the cancer ecosystem. This, along with other treatments aimed at targeting tumor metabolic pathways, may lead to novel treatment strategies for endometrial cancer.

Aurora A Functional Single Nucleotide Polymorphism (SNP) Correlates With Clinical Outcome in Patients With Advanced Solid Tumors Treated With Alisertib, an Investigational Aurora A Kinase Inhibitor

Background

Alisertib (MLN8237) is an investigational, oral, selective Aurora A kinase inhibitor. Aurora A contains two functional single nucleotide polymorphisms (SNPs; codon 31 [F/I] and codon 57 [V/I]) that lead to functional changes. This study investigated the prognostic and predictive significance of these SNPs.

Methods

This study evaluated associations between Aurora A SNPs and overall survival (OS) in The Cancer Genome Atlas (TCGA) database. The Aurora A SNPs were also evaluated as predictive biomarkers for clinical outcomes to alisertib in two phase 2 studies (NCT01045421 and NCT01091428). Aurora A SNP genotyping was obtained from 85 patients with advanced solid tumors receiving single-agent alisertib and 122 patients with advanced recurrent ovarian cancer treated with alisertib plus weekly paclitaxel (n = 62) or paclitaxel alone (n = 60). Whole blood was collected prior to treatment and genotypes were analyzed by PCR.

Findings

TCGA data suggested prognostic significance for codon 57 SNP; solid tumor patients with VV and VI alleles had significantly reduced OS versus those with II alleles (HR 1.9 [VI] and 1.8 [VV]; p < 0.0001). In NCT01045421, patients carrying the VV alleles at codon 57 (n = 53, 62%) had significantly longer progression-free survival (PFS) than patients carrying IV or II alleles (n = 32, 38%; HR 0.5; p = 0.0195). In NCT01091428, patients with the VV alleles at codon 57 who received alisertib plus paclitaxel (n = 47, 39%) had a trend towards improved PFS (7.5 months) vs paclitaxel alone (n = 32, 26%; 3.8 months; HR 0.618; p = 0.0593). In the paclitaxel alone arm, patients with the VV alleles had reduced PFS vs modified intent-to-treat (mITT) patients (3.8 vs 5.1 months), consistent with the TCGA study identifying the VV alleles as a poor prognostic biomarker. No significant associations were identified for codon 31 SNP from the same data set.

Interpretation

These findings suggest that Aurora A SNP at codon 57 may predict disease outcome and response to alisertib in patients with solid tumors. Further investigation is warranted.

•

Aurora A contains two single nucleotide polymorphisms (SNPs) at codons 31 and 57 that lead to functional amino acid changes

•

We evaluated the potential prognostic and predictive value of these SNPs and revealed the SNP at codon 57 may predict disease outcome and response to Alisertib in patients with solid tumors

Alisertib, an investigational Aurora A kinase inhibitor, was evaluated in clinical trials and showed clinically meaningful benefit in patients with solid tumors. Two coding region single nucleotide polymorphisms (SNPs) in the Aurora A gene have been reported to be associated with functional changes of the protien. Here we assessed the prognostic and predictive value of Aurora A SNPs in a range of solid tumors. The results suggest that codon 57 SNP may predict disease outcome and response to alisertib in patients. These findings warrant further investigation and may ultimately provide a patient selection strategy for alisertib in certain cancers.

A phase I trial of intraperitoneal GEN-1, an IL-12 plasmid formulated with PEG-PEI-cholesterol lipopolymer, administered with pegylated liposomal doxorubicin in patients with recurrent or persistent epithelial ovarian, fallopian tube or primary peritoneal cancers: An NRG Oncology/Gynecologic Oncology Group study

OBJECTIVE

The study's purpose was to assess safety and efficacy of escalating doses of weekly GEN-1 with pegylated liposomal doxorubicin (PLD) in patients with recurrent or persistent epithelial ovarian, fallopian tube or primary peritoneal cancers (EOC).

METHODS

Patients had persistent or recurrent platinum-resistant EOC. The trial was a standard 3+3 phase I dose escalation design with patients receiving intravenous PLD 40mg/m² (dose level 1 and 2) or 50mg/m² (dose level 3) every 28days and intraperitoneal GEN-1 at 24mg/m² (dose level 1) or 36mg/m² (dose level 2 and 3) on days 1, 8, 15, and 22 of a 28day cycle. Cycles were repeated every 28days until disease progression. Patients were monitored for toxicity, clinical efficacy, and evidence of systemic and intraperitoneal immunologic effect.

RESULTS

Sixteen evaluable patients received a median of 4cycles (range 1-8). No dose limiting toxicities were found. The adverse side effects were 4 grade 3 anemia, 2 grade 3 abdominal pain, 7 grade 3 neutropenia, and 2 grade 4 neutropenia. A clinical benefit of 57.1% (PR=21.4%; SD=35.7%) was found in the 14 patients with measurable disease. The highest number of partial responses (28.6%) and stable disease (57.1%) were found at dose level 3. The maximum tolerated dose was not reached. Increases in IL-12, IFN-γ, and TNF-α levels were found in peritoneal fluid following GEN-1 treatment.

CONCLUSIONS

GEN-1 in combination with PLD has encouraging clinical benefit and biological activity in recurrent or persistent EOC and warrants further investigation with escalating doses of GEN-1.

A phase I study of sequential ipilimumab in the definitive treatment of node positive cervical cancer: GOG 9929

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Background: The outcome of lymph node positive (LN) cervical cancer (CC) with chemoradiation (CRT) is dismal, especially with involved para-aortic nodes (PAN). The anti-CTLA-4 immune checkpoint inhibitor ipilimumab (ipi) holds promise. We report the safety, tolerability, and efficacy in this GOG phase I study examining sequential ipi after CRT for CC. Methods: Patients (pts) with LN CC were treated with 6 weekly doses of cisplatin (40 mg/m2) and extended field radiation (RT). 2-6 weeks after RT, if there was no progression of disease, sequential ipi was given at the following dose levels: dose level 1: 3mg/kg, level 2: 10mg/kg, and an expansion cohort of 10mg/kg. The primary endpoints (endpts) were the maximum tolerated dose (MTD), and dose-limiting toxicities (DLT) of adjuvant ipi. Secondary endpt included the 1-yr disease free survival (DFS). Translational endpts included the effect of CRT on enumeration and subsets of T-cells, and CTLA4, PD-1 and ICOS expression. Results: 34 pts were enrolled, and 19 pts are evaluable for the endpts: 14 pts went off study to reasons unrelated to the study drug, 1 pt continues in her DLT evaluable period. Of the evaluable pts, all had pelvic LN, with 25% PAN. All pts completed CRT, 90% had 4 cycles of ipi, and the other 10% had 2 cycles of ipi. The ipi MTD was 10 mg/kg. There were 3 pts (16%) with acute grade 3 toxicity (lipase, ↓ANC, rash) which self-resolved. Most of the acute toxicities were grade 1-2 GI distress, rash, endocrinopathies. There were no minor or major RT quality deviations. With a median follow up of 12 months, there were no major late toxicities reported, with a 1-year DFS of 74%. There was no difference in CD4+- and CD8+- T cell levels nor CTLA-4 expression with sequential ipi. CRT itself increased ICOS and PD-1 expression. Conclusions: This study is the first to describe the safety of immunotherapy sequencing with definitive CRT in CC. Our data suggests that immunotherapy is tolerable and shows possible activity in this population with a historical dismal prognosis with standard therapy. CRT increased ICOS and PD-1 expression which was sustained with ipi, illustrative of immune modulation targets for future clinical trials and radioimmunotherapy combinations. Clinical trial information: NCT01711515.

Brain Metastases in Patients with Gynecologic Cancers: A Single Institution Experience and Review of the Literature

Objective:

Brain Metastasis (BM) from primary gynecologic cancers is a rare entity. The advances and successes in the treatment of primary gynecologic malignancies, have led to prolonged survival and, a higher incidence of BM. This study aims to report the experience at our institution in managing these patients, and provide possible data points that may be essential to note as prognostic factors, and see if our findings are consistent with the literature in this subject. We also aim to provide a brief literature review of patients with gynecologic cancers and BM.

Methods:

This is a small single institution retrospective study of 23 patients with a gynecologic malignancy and BM, identified between the years 2007–2015. Data were collected on variables including patient demographics, disease and treatment.

Results:

The median overall survival from the primary diagnosis was 28 months. Median time from diagnosis of BM to death was 9 months.

Conclusion:

The outcomes in our study are similar to what is stated in the current literature with regard to BM from gynecologic malignancies. Our literature search also revealed that the molecular analysis and treatment of the primary tumor remain important to prevent BMs. The tendency of tumors to metastasize varies for one tumor type to another for the same type of tumor. The tendency to develop BM may not only depend on risk factors such as stage, grade, and histology, but also on the genetic profile of the primary tumor. The study suggests that multimodal treatment of BM has better outcomes in managing BM from gynecologic cancers.

Assessing solid tumor response with and without RECIST

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Background: Response Evaluation Criteria in Solid Tumors (RECIST) has become widely accepted as gold standard for response evaluation in clinical trials. It remains underutilized in routine clinical practice. We compared tumor response assessment made with and without RECIST. Methods: This study included patients with solid tumors who underwent imaging from January 2013 to December 2014 at a single academic center. Tumor response was assessed by a radiologist using RECIST and by an oncologist (Onc) and resident (Res) without using RECIST (standard report). Tumor response was classified as progressive disease (PD), stable disease (SD), partial response (PR) and complete response (CR). Agreement in assessment between RECIST and standard report was determined by percent agreement and Kappa statistic. Results: 292 imaging studies were included. Concordance between RECIST and Onc-interpreted standard report is presented in Table 1. Overall agreement between RECIST and Onc-interpreted standard report was 56% (95% CI: 46-65%) and Kappa was 0.31 (95% CI: 0.19-0.44). Similar results were seen between RECIST and Res-interpreted standard report (Table 1). Overall agreement between RECIST and Res-interpreted report was 54% (95% CI: 44%-63%) and Kappa was 0.26 (95% CI: 0.13-0.40). Conclusions: Our study found variability in tumor response assessment between clinicians and radiologists. RECIST-classified PD was often interpreted as SD and vice versa, a distinction that affect treatment decisions. Our study highlights the need to standardize tumor response assessment. [Table: see text]

A Synthetic Lethality Screen Using a Focused siRNA Library to Identify Sensitizers to Dasatinib Therapy for the Treatment of Epithelial Ovarian Cancer

Molecular targeted therapies have been the focus of recent clinical trials for the treatment of patients with recurrent epithelial ovarian cancer (EOC). The majority have not fared well as monotherapies for improving survival of these patients. Poor bioavailability, lack of predictive biomarkers, and the presence of multiple survival pathways can all diminish the success of a targeted agent. Dasatinib is a tyrosine kinase inhibitor of the Src-family kinases (SFK) and in preclinical studies shown to have substantial activity in EOC. However, when evaluated in a phase 2 clinical trial for patients with recurrent or persistent EOC, it was found to have minimal activity. We hypothesized that synthetic lethality screens performed using a cogently designed siRNA library would identify second-site molecular targets that could synergize with SFK inhibition and improve dasatinib efficacy. Using a systematic approach, we performed primary siRNA screening using a library focused on 638 genes corresponding to a network centered on EGFR, HER2, and the SFK-scaffolding proteins BCAR1, NEDD9, and EFS to screen EOC cells in combination with dasatinib. We followed up with validation studies including deconvolution screening, quantitative PCR to confirm effective gene silencing, correlation of gene expression with dasatinib sensitivity, and assessment of the clinical relevance of hits using TCGA ovarian cancer data. A refined list of five candidates (CSNK2A1, DAG1, GRB2, PRKCE, and VAV1) was identified as showing the greatest potential for improving sensitivity to dasatinib in EOC. Of these, CSNK2A1, which codes for the catalytic alpha subunit of protein kinase CK2, was selected for additional evaluation. Synergistic activity of the clinically relevant inhibitor of CK2, CX-4945, with dasatinib in reducing cell proliferation and increasing apoptosis was observed across multiple EOC cell lines. This overall approach to improving drug efficacy can be applied to other targeted agents that have similarly shown poor clinical activity.

A Phase I Study of the SMAC-Mimetic Birinapant in Adults with Refractory Solid Tumors or Lymphoma

The inhibitor of apoptosis (IAP) family of antiapoptotic proteins has been identified as a target for small molecule inhibitors in cancer. Second mitochondrial-derived activator of caspases (SMAC) efficiently and naturally antagonizes IAPs, and preclinical studies have determined that SMAC mimetics have potent anticancer properties. Here, we report a first-in-human trial designed to determine the maximum tolerated dose (MTD), safety, and pharmacokinetics/pharmacodynamics (PK/PD) of birinapant, a novel SMAC mimetic. Patients with advanced solid tumors or lymphoma were enrolled in a 3+3 dose escalation design with birinapant administered intravenously from 0.18 to 63 mg/m(2) once weekly every 3 of 4 weeks. Fifty patients were enrolled to 12 dose cohorts. Birinapant 47 mg/m(2) was determined to be the MTD. At 63 mg/m(2), dose-limiting toxicities included headache, nausea, and vomiting. Two cases of Bell's palsy (grade 2) also occurred at 63 mg/m(2). Birinapant had a plasma half-life of 30 to 35 hours and accumulated in tumor tissue. Birinapant suppressed cIAP1 and increased apoptosis in peripheral blood mononuclear cells and tumor tissue. Prolonged stable disease was observed in 3 patients: non-small cell lung cancer (5 months), colorectal cancer (5 months), and liposarcoma (9 months). Two patients with colorectal cancer had radiographic evidence of tumor shrinkage. In conclusion, birinapant was well tolerated with an MTD of 47 mg/m(2) and exhibited favorable PK and PD properties. Several patients demonstrated stable disease and evidence of antitumor activity. These results support the ongoing clinical trials of birinapant in patients with cancer.

Aurora kinase A mediates epithelial ovarian cancer cell migration and adhesion

Aurora kinase A (AURKA) localizes to centrosomes and mitotic spindles where it mediates mitotic progression and chromosomal stability. Overexpression of AURKA is common in cancer, resulting in acquisition of alternate non-mitotic functions. In the current study, we identified a novel role for AURKA in regulating ovarian cancer cell dissemination and evaluated the efficacy of an AURKA-selective small molecule inhibitor, alisertib (MLN8237), as a single agent and combined with paclitaxel using an orthotopic xenograft model of epithelial ovarian cancer (EOC). Ovarian carcinoma cell lines were used to evaluate the effects of AURKA inhibition and overexpression on migration and adhesion. Pharmacological or RNA interference-mediated inhibition of AURKA significantly reduced ovarian carcinoma cell migration and adhesion and the activation-associated phosphorylation of the cytoskeletal regulatory protein SRC at tyrosine 416 (pSRC(Y416)). Conversely, enforced expression of AURKA resulted in increased migration, adhesion and activation of SRC in cultured cells. In vivo tumor growth and dissemination were inhibited by alisertib treatment as a single agent. Moreover, combination of alisertib with paclitaxel, an agent commonly used in treatment of EOC, resulted in more potent inhibition of tumor growth and dissemination compared with either drug alone. Taken together, these findings support a role for AURKA in EOC dissemination by regulating migration and adhesion. They also point to the potential utility of combining AURKA inhibitors with taxanes as a therapeutic strategy for the treatment of EOC patients.

Refractory fallopian tube carcinoma - current perspectives in pathogenesis and management

Fallopian tube carcinoma (FTC) is considered a rare malignancy, but recent evidence shows that its incidence may have been underestimated. Risk-reducing salpingo-oophorectomy (RRSO) in breast cancer susceptibility gene (BRCA)-positive women has provided a unique opportunity to study the pathogenesis of FTC and ovarian carcinomas. Newer data now suggest that most high-grade serous cancers of the ovary originate in the fimbrial end of the fallopian tube. Due to the presumed rarity of FTC, most current and more recent ovarian cancer clinical trials have now included patients with FTC. The treatment guidelines recommend similar overall management and that the same chemotherapy regimens be used for epithelial ovarian cancers and FTC.

Influence of bevacizumab on vaginal cuff evisceration eight months after ovarian cancer cytoreduction surgery: A case report

•44 year old woman treated with bevacizumab for metastatic epithelial ovarian cancer•The patient experienced vaginal cuff dehiscence and evisceration at 8 months post-operatively.•Metastasis at the surgical site and chronic inflammation implicated.

Phase II clinical activity and tolerability of the SMAC-mimetic birinapant (TL32711) plus irinotecan in irinotecan-relapsed/refractory metastatic colorectal cancer

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Background: Birinapant (B) is a SMAC-mimetic that inhibits IAPs and has potent preclinical anti-tumor synergy combined with TNFa-inducing chemotherapies [i.e irinotecan (I)]. B and I combination is well-tolerated and has encouraging activity in a phase 1 study. This study tested B+I with an ascending dose strategy (ADS) of B to mitigate Bell’s palsy (BP) risk, an unusual and reversible side effect of SMAC mimetics. Methods: I at 350mg/m2 IV q3weeks was administered with B weekly (2 of 3 weeks). The dose of B was titrated incrementally during Cycle 1: C1D1 at 5.6mg/m2 and C1D8 at 11mg/m2 for ADS. For Cycle 2 (C2) and ongoing treatment, the B dose was 22mg/m2 or 35mg/m2, which were the MTD and DLT (BP) dose levels when combined with I from the Ph 1 study. Safety and clinical activity for KRAS mutant (KRAS-MT) and wild-type (KRAS-WT) were assessed in 3 cohorts: (1) at 22mg/m2 for CRC KRAS MT; (2) 22mg/m2 for CRC KRAS WT; (3) 35mg/m2 for CRC KRAS MT. Results: 51 patients (pts) with CRC had a median number of 4 prior regimens with 47 refractory/relapsed to irinotecan (92%). Tolerability was comparable to I alone. There were 2 PRs (4%), 27 SD (>2 cycles; 53%, median 4.7 mo), 17 PD (33%), and 5 non- evaluable pts (9%) for an overall clinical benefit (CR+PR+SD) rate of 57%. Median progression-free survival (PFS) was 2.1 months, and 6 mo PFS was 20%. KRAS MT CRC with prior I had a median PFS of 2.9 mo and 6 mo PFS of 25% (n=20). KRAS WT CRC with prior I had a median PFS of 1.4 mo and 6 mo PFS of 17% (n=18). The ADS seemed to reduce BP risk. No BP events occurred among 40 pts (22mg/m2 with ADS), compared to 1 of 7 pts (22mg/m2 without ADS). In the 35mg/m2 cohort, 1 BP event occurred among 12 pts (with ADS), compared to 3 of 6 (35mg/m2 without ADS). Conclusions: B + I demonstrated clinical benefit in pts refractory/relapsed to irinotecan, with greatest benefit in KRAS MT CRC. The ADS may provide a mitigation strategy for BP risk. Prior studies with I retreatment have showed no benefit in KRAS MT CRC. Comparable CRC pts with best supportive care have 6 mo PFS of 2%. Clinical activity supports the hypothesis for therapeutic synergy of B + I, with I as a TNFa-inducing agent. Further study of this combination is warranted. Clinical trial information: NCT01188499.

A phase I study of birinapant (TL32711) combined with multiple chemotherapies evaluating tolerability and clinical activity for solid tumor patients

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Background: Birinapant (B) is a SMAC-mimetic that inhibits IAPs with excellent tolerability, drug exposure, target suppression and apoptotic pathway activation in clinical studies. Preclinical studies demonstrate potent anti-tumor synergy when B is combined with TNFa-inducing chemotherapies (CT). Methods: Escalating doses of B were combined with CT in a 5-arm 3+3 phase 1 study for adults (pts) with relapsed/refractory solid tumors to determine maximum tolerated dose (MTD), pharmacokinetics (PK), and efficacy to identify indications for further studies. The arms included carboplatin/paclitaxel (CP), irinotecan (I), docetaxel (D), gemcitabine (G), and liposomal doxorubicin (LD). Results: 124 pts were treated with B at doses of 2.8 to 47 mg/m2. The MTD of B for each arm was CP (47 mg/m2); I (22 mg/m2); D (47 mg/m2). The proposed G regimen could not be administered in heavily pretreated pts and B could not be evaluated for dose escalation; this arm was discontinued and no dose-limiting toxicities (DLT) occurred. LD drug shortage prevented dose escalation for B > 35mg/m2 (MTD not reached). B did not limit CT administration for CP, I, D, LD, supporting tolerable combination of B with CT. B-associated toxicity of Bell’s palsy (Grade 2) was considered a DLT and noted at higher dose levels for I, D, and LD, but not CP. This unusual reversible toxicity occurred during cycle 1 in 7 pts. Six of these pts continued therapy without recurrence. PK studies demonstrated no effect of B on CT. Except for CP, CT did not change the PK of B. CP increased plasma PK for B, possibly due to OATP1B3 transporter effects, but without increased B toxicities. 11 pts had a partial response, 61 pts had stable disease (>2 cycles, median 4.6 mo) and 37 pts had progressive disease as their best response, with clinical benefit (CR+PR+SD) of 58%. Conclusions: B can be combined with excellent tolerability with multiple CT at standard dosing. B plus CT demonstrated clinical benefit in many tumor types. Notable clinical activity occurred with I + B in pts who had failed prior I. These results support planning for further clinical studies of the I + B, and support the hypothesis for TNFa-mediated I + B synergy. Clinical trial information: NCT01188499.

Potential role of mTORC2 as a therapeutic target in clear cell carcinoma of the ovary

The goal of this study was to examine the role of mTOR complex 2 (mTORC2) as a therapeutic target in ovarian clear cell carcinoma (CCC), which is regarded as an aggressive, chemoresistant histologic subtype. Using tissue microarrays of 98 primary ovarian cancers [52 CCCs and 46 serous adenocarcinomas (SAC)], activation of mTORC2 was assessed by immunohistochemistry. Then, the growth-inhibitory effect of mTORC2-targeting therapy, as well as the role of mTORC2 signaling as a mechanism for acquired resistance to the mTOR complex 1 (mTORC1) inhibitor RAD001 in ovarian CCC, were examined using two pairs of RAD001-sensitive parental (RMG2 and HAC2) and RAD001-resistant CCC cell lines (RMG2-RR and HAC2-RR). mTORC2 was more frequently activated in CCCs than in SACs (71.2% vs. 45.7%). Simultaneous inhibition of mTORC1 and mTORC2 by AZD8055 markedly inhibited the proliferation of both RAD001-sensitive and -resistant cells in vitro. Treatment with RAD001 induced mTORC2-mediated AKT activation in RAD001-sensitive CCC cells. Moreover, increased activation of mTORC2-AKT signaling was observed in RAD001-resistant CCC cells compared with the respective parental cells. Inhibition of mTORC2 during RAD001 treatment enhanced the antitumor effect of RAD001 and prevented CCC cells from acquiring resistance to RAD001. In conclusion, mTORC2 is frequently activated, and can be a promising therapeutic target, in ovarian CCCs. Moreover, mTORC2-targeted therapy may be efficacious in a first-line setting as well as for second-line treatment of recurrent disease developing after RAD001-treatment.

A phase II evaluation of motesanib (AMG 706) in the treatment of persistent or recurrent ovarian, fallopian tube and primary peritoneal carcinomas: a Gynecologic Oncology Group study

OBJECTIVES

Vascular endothelial growth factors (VEGF) and their receptors have a critical role in stimulating the growth of ovarian cancer cells. Motesanib is a small molecule inhibitor of multiple receptor tyrosine kinases including VEGF receptors 1-3, as well as c-KIT and platelet-derived growth factor which are related to the VEGF family.

PATIENTS AND METHODS

Twenty-two eligible patients with recurrent ovarian, fallopian tube or primary peritoneal carcinoma were treated with an oral daily dose of 125 mg of motesanib. Peripheral blood was analyzed for circulating tumor cells (CTC) and circulating endothelial cells/circulating endothelial progenitors (CEC/CEP), VEGF levels and cell-free circulating DNA (cfDNA).

RESULTS

The study was abruptly halted after four patients developed posterior reversible encephalopathy syndrome. One patient had a partial response and seven patients had stable disease at the time they were removed from study treatment. Twelve of the 22 patients (50%) had indeterminate responses at trial closure. Early closure without clinical efficacy data precludes meaningful correlative studies.

CONCLUSIONS

The serious central nervous system toxicity observed in patients with recurrent ovarian cancer precluded full examination of this agent in this population. There were no clear cut explanations for the high incidence of this known class effect in the study population compared with patients with other cancers.

A phase II evaluation of gefitinib in the treatment of persistent or recurrent endometrial cancer: a Gynecologic Oncology Group study

BACKGROUND

A phase II trial was performed to evaluate the efficacy and safety of gefitinib in patients with persistent/recurrent endometrial cancer.

METHODS

Women with histologically confirmed persistent/recurrent endometrial cancer were treated with 500mg oral gefitinib daily until progression or severe toxicity, with progression-free survival (PFS) at six months as the primary endpoint. Tumor expression of total epidermal growth factor receptor (EGFR), estrogen receptor (ER), progesterone receptor A (PRA) and B (PRB), Ki67, pEGFR and activated extracellular signal-regulated kinase (pERK) were examined pre- and post-treatment. EGFR was sequenced, and serum concentrations of soluble EGFR (sEGFR) at baseline also were examined.

RESULTS

Of 29 patients enrolled, 26 were evaluable for efficacy and toxicity. Four patients experienced PFS ≥6 months, and one had a complete response which was not associated with an EGFR mutation. The concentration of sEGFR in pretreatment serum was positively correlated with overall survival (OS), but not with responsiveness to gefitinib in this small patient cohort. Expression of tumor biomarkers was not associated with PFS or OS. Co-expression of ER with PRA in primary and recurrent tumors, and pEGFR with pERK in primary tumors was observed.

CONCLUSIONS

This treatment regimen was tolerable but lacked sufficient efficacy to warrant further evaluation in this setting. The possible association between serum sEGFR concentrations and OS, and temporal changes in expression of pEGFR and pERK and the documented CR of one patient are interesting and warrant additional investigation.

Ovarian cancer, version 3.2012

These NCCN Guidelines Insights focus on the major updates for the 2012 NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Ovarian Cancer by describing how and why the new recommendations were made. The 6 update topics were selected based on recent important updates in the guidelines and on debate among panel members about recent clinical trials, and include: 1) screening, 2) diagnostic tests for assessing pelvic masses, 3) primary treatment using neoadjuvant chemotherapy, 4) primary adjuvant treatment using bevacizumab in combination with chemotherapy, 5) therapy for recurrent disease, and 6) management of drug/hypersensitivity reactions. These NCCN Guidelines Insights also discuss why some recommendations were not made (eg, panel members did not feel the new data warranted changing the guideline). See "Updates" in the NCCN Guidelines for Ovarian Cancer for a complete list of all the recent revisions.

Lapatinib and potential prognostic value of EGFR mutations in a Gynecologic Oncology Group phase II trial of persistent or recurrent endometrial cancer

OBJECTIVE

A phase II trial was performed to evaluate the efficacy and safety of the tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR) and HER2, lapatinib, and to explore EGFR, HER2 (EGFR2), phosphorylated ERK MAP kinase (pERK), and Ki67 expression, as well as EGFR mutations in persistent/recurrent endometrial cancer (EC).

METHODS

Women with histologically-confirmed, measurable, persistent/recurrent EC following one or two prior regimens were eligible and treated with 1500 mg oral lapatinib daily until progression or severe toxicity. A 2-stage group sequential design was used to evaluate the regimen with 6 month PFS as the primary endpoint. The trial had a 10% type I error rate with 90% power. EGFR, HER2, pERK, and Ki67 were evaluated by immunohistochemistry (IHC) from hysterectomy specimens, pre-treatment biopsies, and post-treatment biopsies (when available). Exons 18-21 of EGFR were sequenced.

RESULTS

Three patients of 30 evaluable had PFS ≥6 months, one had a partial response, seven had stable disease, 21 had progressive disease and one was indeterminate. Three mutations in EGFR were identified. Two of these, L688F and K754E, were not associated with response or PFS. However, a newly identified mutation in exon 18, E690K, occurred in the patient with a partial response and progression-free survival extending past six months.

CONCLUSION

While lapatinib has limited activity in unselected cases, the identification of a previously unreported mutation in EGFR (E690K) with a response suggests that lapatinib may be beneficial in some cases of EC.

Phase II study of MLN8237 (alisertib), an investigational Aurora A kinase inhibitor, in patients with platinum-resistant or -refractory epithelial ovarian, fallopian tube, or primary peritoneal carcinoma

OBJECTIVES

Aurora A kinase (AAK), a key mitotic regulator, is implicated in the pathogenesis of several tumors, including ovarian cancer. This single-arm phase II study assessed single-agent efficacy and safety of the investigational AAK inhibitor MLN8237 (alisertib), in patients with platinum-refractory or -resistant epithelial ovarian, fallopian tube, or primary peritoneal carcinoma.

METHODS

Adult women with malignant, platinum-treated disease received MLN8237 50mg orally twice daily for 7 days plus 14 days' rest (21-day cycles). The primary endpoint was combined objective tumor response rate per Response Evaluation Criteria in Solid Tumors (RECIST) and/or CA-125 criteria. Secondary endpoints included response duration, clinical benefit rate, progression-free survival (PFS), time-to-progression (TTP), and safety.

RESULTS

Thirty-one patients with epithelial ovarian (n=25), primary peritoneal (n=5), and fallopian tube carcinomas (n=1) were enrolled. Responses of 6.9-11.1 month duration were observed in 3 (10%) patients with platinum-resistant ovarian cancer. Sixteen (52%) patients achieved stable disease with a mean duration of response of 2.86 months and which was durable for ≥3 months in 6 (19%). Median PFS and TTP were 1.9 months. Most common drug-related grade≥3 adverse events were neutropenia (42%), leukopenia (23%), stomatitis, and thrombocytopenia (each 19%); 6% reported febrile neutropenia.

CONCLUSIONS

These data suggest that MLN8237 has modest single-agent antitumor activity and may produce responses and durable disease control in some patients with platinum-resistant ovarian cancer. MLN8237 is currently undergoing evaluation in a phase I/II trial with paclitaxel in recurrent ovarian cancer.

Phase II evaluation of dasatinib in the treatment of recurrent or persistent epithelial ovarian or primary peritoneal carcinoma: a Gynecologic Oncology Group study

OBJECTIVES

Preclinical data suggest an important role for the sarcoma proto-oncogene tyrosine kinase (SRC) in the oncogenesis of epithelial ovarian cancer (EOC) or primary peritoneal carcinoma (PPC). The Gynecologic Oncology Group (GOG) conducted a Phase II trial to evaluate the efficacy and safety of dasatinib, an oral SRC-family inhibitor in EOC/PPC, and explored biomarkers for possible association with clinical outcome.

METHODS

Eligible women had measurable, recurrent or persistent EOC/PPC and had received one or two prior regimens which must have contained a platinum and a taxane. Patients were treated with 100mg orally daily of dasatinib continuously until progression of disease or adverse effects prevented further treatment. Primary endpoints were progression-free survival (PFS)≥6months and response rate. Serial plasma samples were assayed for multiple biomarkers. Circulating free DNA was quantified as were circulating tumor and endothelial cells.

RESULTS

Thirty-five (35) patients were enrolled in a two-stage sequential design. Of the 34 eligible and evaluable patients, 20.6% (90% confidence interval: 10.1%, 35.2%) had a PFS≥6months; there were no objective responses. Grade 3-4 toxicities were gastrointestinal (mostly nausea and emesis; n=4), pulmonary (dyspnea and/or pleural effusion; n=4) and pain (n=5), and infrequent instances of anemia, malaise, insomnia, rash, and central nervous system hemorrhage. Lack of clinical activity limited any correlation of biomarkers with outcome.

CONCLUSION

Dasatinib has minimal activity as a single-agent in patients with recurrent EOC/PPC.