High grade adverse event reporting and enrolment in gynecologic oncology clinical trials

OBJECTIVE

The primary objective is to assess factors associated with treatment related high grade (CTCAE grade ≥ 3) adverse event (AE) reporting among participants in gynecologic oncology clinical trials.

METHODS

All AEs recorded in the Princess Margaret Clinical Trial adverse event database between 01/2016 and 12/2018 were evaluated. Gynecologic oncology clinical trials assessing systemic therapy were included. Inferential statistics on risk factors of related grade ≥ 3 adverse event reporting and GEE logistic models with Odds Ratios (OR) were performed. Multivariable analysis adjusting for age, clinical trial phase, sponsor, and therapy type.

RESULTS

The gynecology cancer clinical trials accrued 317 unique patients (359 nested on trials) in 42 systemic therapy trials. In the period, 17,175 related AEs were reported in the gynecological cancer trials, 7.4% were grade ≥ 3. On multivariable analysis, no odds differences of grade ≥ 3 related AEs were detected according to study phase. Patients in immunotherapy clinical trials had lower odds of related grade ≥ 3 AEs than patients on targeted or other therapy (adjusted OR [aOR] 0.43; 95% CI 0.24-0.75). There was greater odds of related grade ≥ 3 AEs in clinical trials assessing combination vs single therapeutics (aOR 2.26, 95% CI 1.34-3.80). Patients aged ≥65 (aOR 1.77; 95% CI 1.08-2.89) had greater odds of related grade ≥ 3 AEs than patients aged 50 to 65 years. When compared to other disease sites, the odds of having a grade  ≥ 3 related AE reported in gynecology clinical trials was no different.

CONCLUSIONS

In this cohort, factors influencing the odds of related grade ≥ 3 AE reporting in gynecologic trials included type of therapy and age. The study phase did not correlate with odds of high-grade AE reporting.

Identifying Mechanisms of Resistance by Circulating Tumor DNA in EVOLVE, a Phase II Trial of Cediranib Plus Olaparib for Ovarian Cancer at Time of PARP Inhibitor Progression

PURPOSE

To evaluate the use of blood cell-free DNA (cfDNA) to identify emerging mechanisms of resistance to PARP inhibitors (PARPi) in high-grade serous ovarian cancer (HGSOC).

EXPERIMENTAL DESIGN

We used targeted sequencing (TS) to analyze 78 longitudinal cfDNA samples collected from 30 patients with HGSOC enrolled in a phase II clinical trial evaluating cediranib (VEGF inhibitor) plus olaparib (PARPi) after progression on PARPi alone. cfDNA was collected at baseline, before treatment cycle 2, and at end of treatment. These were compared with whole-exome sequencing (WES) of baseline tumor tissues.

RESULTS

At baseline (time of initial PARPi progression), cfDNA tumor fractions were 0.2% to 67% (median, 3.25%), and patients with high ctDNA levels (>15%) had a higher tumor burden (sum of target lesions; P = 0.043). Across all timepoints, cfDNA detected 74.4% of mutations known from prior tumor WES, including three of five expected BRCA1/2 reversion mutations. In addition, cfDNA identified 10 novel mutations not detected by WES, including seven TP53 mutations annotated as pathogenic by ClinVar. cfDNA fragmentation analysis attributed five of these novel TP53 mutations to clonal hematopoiesis of indeterminate potential (CHIP). At baseline, samples with significant differences in mutant fragment size distribution had shorter time to progression (P = 0.001).

CONCLUSIONS

Longitudinal testing of cfDNA by TS provides a noninvasive tool for detection of tumor-derived mutations and mechanisms of PARPi resistance that may aid in directing patients to appropriate therapeutic strategies. With cfDNA fragmentation analyses, CHIP was identified in several patients and warrants further investigation.

A phase I study of the Wee1 kinase inhibitor adavosertib (AZD1775) in combination with chemoradiation in cervical, upper vaginal, and uterine cancers

OBJECTIVE

Wee1 kinase is a crucial regulator of the G2/M checkpoint which prevents entry of damaged DNA into mitosis. Adavosertib (AZD1775), a selective inhibitor of Wee1, induces G2 escape and increases cytotoxicity when combined with DNA damaging agents. We aimed to evaluate the safety and efficacy of adavosertib in combination with definitive pelvic radiotherapy and concurrent cisplatin in patients with gynecological cancers.

METHODS

A multi-institutional, open-label phase I trial was designed to assess dose escalation (3+3 design) of adavosertib in combination with standard chemoradiation. Eligible patients with locally advanced cervical, endometrial or vaginal tumors were treated with a 5-week course of pelvic external beam radiation 45-50 Gy in 1.8-2 Gy daily fractions plus concurrent weekly cisplatin 40 mg/m2 and adavosertib 100 mg/m2 on days 1, 3 and 5 of each week during chemoradiation. The primary endpoint was to determine the recommended phase II dose of adavosertib. Secondary endpoints included toxicity profile and preliminary efficacy.

RESULTS

Ten patients were enrolled (nine locally advanced cervical and one endometrial cancer). Two patients experienced a dose-limiting toxicity at dose level 1 (adavosertib 100 mg by mouth daily on days 1, 3 and 5), including one patient with grade 4 thrombocytopenia, and one with treatment hold >1 week due to grade 1 creatinine elevation and grade 1 thrombocytopenia. At dose level -1 (adavosertib 100 mg by mouth daily on days 3 and 5), one out of five patients enrolled had a dose-limiting toxicity in the form of persistent grade 3 diarrhea. The overall response rate at 4 months was 71.4%, including four complete responses. At 2 years follow-up, 86% of patients were alive and progression-free.

CONCLUSION

The recommended phase II dose could not be determined due to clinical toxicity and early trial closure. Preliminary efficacy appears promising, yet selecting the adequate dose/schedule in combination chemoradiation warrants further investigation to limit overlapping toxicities.

Clinical outcome and biomarker assessments of a multi-centre phase II trial assessing niraparib with or without dostarlimab in recurrent endometrial carcinoma

This multi-centre, non-randomized, open-label, phase II trial (NCT03016338), assessed niraparib monotherapy (cohort 1, C1), or niraparib and dostarlimab (cohort 2, C2) in patients with recurrent serous or endometrioid endometrial carcinoma. The primary endpoint was clinical benefit rate (CBR), with ≥5/22 overall considered of interest. Secondary outcomes were safety, objective response rate (ORR), duration of response, progression free survival and overall survival. Translational research was an exploratory outcome. Potential biomarkers were evaluated in archival tissue by immunohistochemistry and next generation sequencing panel. In C1, 25 patients were enrolled, and CBR was 20% (95% CI: 9-39) with median clinical benefit duration of 5.3 months. The ORR was 4% (95% CI: 0-20). In C2, 22 patients were enrolled, and the CBR was 31.8% (95% CI: 16-53) with median clinical benefit duration of 6.8 months. The ORR was 14% (95% CI: 3-35). No new safety signals were detected. No significant association was detected between clinical benefit and IHC markers (PTEN, p53, MMR, PD-L1), or molecular profiling (PTEN, TP53, homologous recombination repair genes). In conclusion, niraparib monotherapy did not meet the efficacy threshold. Niraparib in combination with dostarlimab showed modest activity.

Management of Malignant Bowel Obstruction: An Innovative Proactive Outpatient Nurse-Led Model of Care for Patients With Advanced Gynecologic Cancer

BACKGROUND

Malignant bowel obstruction (MBO) in patients with advanced gynecologic cancer (GyCa) can negatively impact clinical outcomes and quality of life. Oncology nurses can support these patients with adequate tools/processes.

PROBLEM

Patients with GyCa with/at risk of MBO endure frequent emergency or hospital admissions, impacting patient care.

APPROACH

Optimizing oncology nurses' role to improve care for patients with GyCa with/at risk of MBO, the gynecology oncology interprofessional team collaborated to develop a proactive outpatient nurse-led MBO model of care (MOC).

OUTCOMES

The MBO MOC involves a risk-based algorithm engaging interdisciplinary care, utilizing standardized tools, risk-based assessment, management, and education for patients and nurses. The MOC has improved patient-reported confidence level of bowel self-management and decreased hospitalization. Following education, nurses demonstrated increased knowledge in MBO management.

CONCLUSIONS

An outpatient nurse-led MBO MOC can improve patient care and may be extended to other cancer centers, fostering collaboration and best practice.

Patient self-reporting of tolerability using PRO-CTCAE in a randomized double-blind, placebo-controlled phase II trial comparing gemcitabine in combination with adavosertib or placebo in patients with platinum resistant or refractory epithelial ovarian carcinoma

BACKGROUND

A double-blind, randomized, placebo-controlled, phase 2 trial assessed gemcitabine in combination with the wee1 inhibitor adavosertib or placebo in platinum resistant or refractory high grade serous ovarian cancer (HGSOC), demonstrating improved progression free and overall survival favouring the adavosertib/gemcitabine arm. An exploratory objective of the study included the PRO-CTCAE assessment, to capture self-reporting of frequency, severity and/or interference of symptomatic adverse events (syAEs).

METHODS

PRO-CTCAE items at baseline, days 1 and 15 of each cycle and off treatment, were completed in two centres, with the objective of characterizing syAEs in the first three months of therapy. The maximum post-baseline score proportion for each syAE was tabulated per patient. The 12-week area under the curve (AUC12w) as a measure of syAE over-time and incremental AUC12w (iAUC12w) for adjustment to baseline syAEs.

RESULTS

Sixty-one patients were approached for PRO-CTCAE surveys and 55 were evaluable. Among patients with HGSOC, 28 received gemcitabine/adavosertib (arm A) and 19 gemcitabine/placebo (arm B). Survey completion rates were high. The proportion of participants with positive (≥1) PRO-CTCAE scores was higher for difficulty swallowing with gemcitabine/adavosertib (arm A 35.7% vs arm B 5.3%, p = 0.02). The high score (≥3) syAEs showed more frequent diarrhea with gemcitabine/adavosertib (arm A 25% vs arm B 0%, p = 0.03). The proportions of worsening syAEs over time were higher in patients receiving gemcitabine/adavosertib for difficulty swallowing (arm A 35.7% vs arm B 5.3%; p = 0.03) and fatigue severity (arm A 71.43% vs arm B 42.1%; p = 0.04).

CONCLUSIONS

The longitudinal assessment of patient self-reported tolerability showed greater difficulty swallowing and fatigue severity in patients receiving gemcitabine/adavosertib, compared to gemcitabine/placebo. PRO-CTCAE provides complementary and objective assessment of drug tolerability from a patient's perspective.

Pembrolizumab, maveropepimut-S, and low-dose cyclophosphamide in advanced epithelial ovarian cancer: Results from phase 1 and expansion cohort of PESCO trial

5505

Background: Platinum-resistant ovarian cancer (PROC) continues to have a poor prognosis. Maveropepimut-S (MVP-S, namely DPX-Survivac) leverages the lipid-based DPX delivery platform to educate a specific and persistent T cell-based immune response to 5 HLA-restricted peptides from survivin, a cancer-related protein commonly upregulated in several cancers. MVP-S in combination with Pembrolizumab (Pemb) and low-dose Cyclophosphamide (CPA) is expected to enhance immune response. This trial aims to assess the safety and efficacy of this regimen in patients (pts) with PROC. Methods: Phase 1 escalation cohort allowed all PROC subtypes and comprised 2 dose levels (DL) of MVP-S with 1 initial dose 0.25 mL followed by boosters of 0.25 mL (DL1) or 0.5mL (DL2) SC q6w, combined with CPA (50 mg BID every other week) and Pemb (200 mg q3w). Dose escalation was performed using 3+3 design. Dose-limiting toxicities (DLT) were defined as G4 non-hematologic, ≥G3 persistent non-hematologic toxicity, laboratory value or febrile neutropenia; ≥G2 persistent injection site skin ulceration ( > 1wk) or allergic/immune reactions by CTCAE v4.03. DL was considered safe if ≤1 DLT occurred in 6 pts until 21 days after initial and first boosting dose. Pts with high-grade serous (HGSOC) or endometrioid ovarian cancer were allowed in the Phase 2 expansion cohort (P2EC) and treated with the Recommended Phase 2 Dose (RP2D). Response was assessed every 6 wks. Activity in P2EC was defined as at least 2/10 partial response (PR) or stable disease (SD) for 12 wks according to RECIST 1.1. Primary endpoint is overall response rate (ORR), and secondary includes safety, PFS, and OS. Biopsies and blood draws were performed prior to and on treatment for genomic analysis, immune profiling and ctDNA. Results: Twenty-six pts were enrolled, 24 were evaluable for safety (8 DL1, 6 DL2, and 10 in P2EC). HGSOC represented 62% of phase I and 100% of P2EC. Median age was 61y (49-78). Pts received a median of 4 (1-7) prior lines of therapy. Median cycles of MVP-S were 2 (1-8). Toxicity G4/G3/G2 occurred in 1/3/7 pts of DL1 and 0/3/6 of DL2. G3/G2 immune-related AE (irAE) and injection site reactions (ISR) were observed in 1/1 and 1/3 pts treated at DL1, and in 1/0 and 2/2 pts at DL2, respectively. DL1 was selected as RP2D due to the occurrence of nephritis and ISR G3 at DL2. No AEs were qualified as DLT. On the P2EC, 5 G3 (1 irAE, 0 ISR) and 28 G2 (0 irAE, 3 ISR) toxicities were observed. At Phase 1, one pt with MSI-High clear cell subtype has ongoing CR after 26 mos of follow-up, 2 pts had PR and 6 SD.There were 1 PR and 3 SD on P2EC, of which 1 and 2, respectively, achieved response > 12wks. Conclusions: The combination of MVP-S, low-dose CPA, and Pemb was tolerable and met the efficacy endpoint in the expansion cohort in heavily treated PROC. Immuno-genomic correlative analyses are ongoing. Clinical trial information: NCT03029403. [Table: see text]

Pharmacokinetic and pharmacodynamic analysis of adavosertib in advanced ovarian cancer

5579

Background: Adavosertib (AZD-1775) is a potent small molecule inhibitor of Wee-1, currently in clinical development. In a double-blind, placebo-controlled, phase 2 trial (NCT02151292), adavosertib and gemcitabine significantly prolonged progression-free survival (PFS) and overall survival (OS) in patients with recurrent platinum-resistant or platinum-refractory high grade serous ovarian cancer (HGSOV) compared to gemcitabine alone. We investigated whether plasma and intra-tumoral adavosertib concentrations correlated with survival in these patients. Methods: Adavosertib was administered orally on Days 1, 2, 8, 9, 15 and 16 at 175 mg per day, and gemcitabine was administered on Days 1, 8 and 15 at 1000 mg/m2 every 28 days. Serial blood samples were collected on Day 1 of cycle 1 after adavosertib administration. Tumor biopsies were taken 1-2 weeks after initiation of study treatments. Plasma and tumor adavosertib concentrations were determined using validated HPLC-MS/MS. Patients were divided into groups with plasma or tumor adavosertib concentrations above or below the biologically active concentration (BAC) of 125 ng/ml (Leijen et al, J Clin Onco 2016). Survival was described using the Kaplan-Meier method. Results: Among 61 HGSOV patients who received adavosertib, plasma samples were available in 47, and tumor samples were available in 31 patients. Among 25 non-HGSOV patients (exploratory cohort), plasma and tumor samples were available in 21 and 17 patients respectively. The mean maximum adavosertib concentration (Cmax) was 355.3 ± 120.9 ng/ml and 358.6 ± 117.9 ng/ml respectively. Cmax was above BAC in all patients. The mean tumor adavosertib concentration was 609.2 ± 1129.2 ng/ml (range: 0.47 – 5501 ng/ml) for HGSOV patients, and 964.2 ± 1611.2 ng/ml (range: 0.22 – 6116 ng/ml) for non-HGSOV patients. There was no correlation between Cmax and tumor adavosertib concentrations. In HGSOV, the median PFS was 5.8 months for patients with tumor concentrations above BAC, and 3.5 months for those with tumor concentrations below BAC (Hazard ratio (HR): 0.46, 95% confidence interval: 0.19 – 1.14, p = 0.06). No difference in PFS was seen in non-HGSOV patients according to tumor adavosertib concentration. Tumor adavosertib concentration did not correlate with OS. Conclusions: Although Cmax was above BAC in all patients, there was a high variability in tumor adavosertib concentrations. In HGSOV, higher tumor adavosertib concentration was associated with a trend towards improved PFS, but not OS. Our results indicate that the current adavosertib dosing regimen may not produce the desired concentrations in tumors for some patients, and further optimization may be needed.

A randomized phase II study of bevacizumab and weekly anetumab ravtansine or weekly paclitaxel in platinum-resistant or refractory ovarian cancer NCI trial#10150

5514

Background: Mesothelin and its binder, antigen-CA125, are highly expressed in high grade serous and endometrioid ovarian cancers (HGOC) and, can inhibit paclitaxel-induced cell death. Anetumab ravtansine (AR) is a fully-human antibody directed at the mesothelin antigen, conjugated to a tubulin polymerization inhibitor. We assessed the safety and activity of the combination AR/bevacizumab (ARB) versus weekly paclitaxel/bevacizumab (PB) in patients (pts) with platinum resistant HGOC. Methods: An initial run-in phase I assessed the safety of ARB. After determination of the recommended phase 2 dose (RP2D), a multicenter 1:1 randomized phase 2 trial was designed to evaluate the progression free survival (PFS) in pts with platinum resistant/refractory HGOC. Pts were stratified by platinum resistant or refractory and prior bevacizumab (bev). Eligibility required measurable disease and mesothelin tested positive centrally on archival tissue by IHC. No limitation on the number of prior lines of therapy. A futility analysis was planned at 35 PFS events. The control arm was weekly intravenous paclitaxel 80mg/m2 with bev 10mg/kg every 2 weeks. A CT was performed every 8 weeks for RECIST1.1 assessment. The toxicities were reported according to CTCAE version 5.1. NCT03587311. Results: 7 pts were enrolled in the run-in phase 1 and the RP2D determined as bev (10mg/kg) biweekly with AR (2.2mg/kg) weekly on a 28 day-cycle. In the phase 2, 57 pts were enrolled, 28 pts in the ARB and 29 pts in the control group. The positivity rate for mesothelin screening was 88%. Pts were heavily pre-treated, median prior lines of 3 (range (1-9) with 24 pts received prior bev (42%) and 13 pts were platinum refractory (7 in ARB and 6 in PB). At the time of 35 PFS events, one CR and 4 PR were observed (ORR = 18%) in the ARB arm, versus no CR and 16 PR in the weekly PB (ORR = 55%). The estimated median PFS was 5.3 (95% CI: 3.7-7.4) months for ARB and 9.6 (95% CI: 7.4-17.4) months for PB (HR = 1.7(95% CI: 0.9-3.4)). The median number of cycles were 4 (1, 29) and 8 (1, 19) respectively. The most common treatment-related AEs in the ARB arm were mostly grade 1/2 increase AST (71%) and ALT (64%), thrombocytopenia (61%), fatigue (57%), and peripheral neuropathy (46%). In the PB arm, the most common treatment-related AE were anemia (66%), neutropenia (59%), epistaxis (48%), fatigue (45%) and peripheral neuropathy (45%). Conclusions: At the time of futility analysis, weekly PB had better outcome than weekly ARB leading to the study termination. Molecular and blood analyses are on-going to assess potential biomarkers of response. This study highlights the importance of randomization in assessment of novel therapies and potential for re-challenge with bevacizumab. These data show that weekly PB is an effective regimen and can be considered as the control arm in platinum resistant HGOC. Clinical trial information: NCT03587311.

OZM-114: Phase Ib expansion study of CX-5461in patients with solid tumors and BRCA2 and/or PALB2 mutation

TPS5621

Background: Pre-clinical and clinical data demonstrate that CX-5461 selectively kills HR deficient cancer cells through stabilizing G4 structures and inducing replication-dependent DNA damage. Phase 1 studies suggest CX-5461 has clinical activity and warrants further investigation in HR-deficient tumors, including those with pathogenic BRCA2 and PALB2 mutation. The recommended phase 2 dose (RP2D) requires further refinement to establish the chronic tolerable dose for further phase 2 trials, particularly regarding the incidence of ocular toxicity. The doses of 325mg/m2 and 250mg/m2 were selected for this study expansion cohorts because it is well within the efficacy range and below the first occurrence of ocular toxicity in a previous study. Methods: This is an open-label, multi-center, phase 1b study designed to determine a tolerable dose of CX-5461 in patients with ovarian, pancreatic, prostate, and breast cancers for Phase II trials. Eligible patients will be enrolled into two cohorts: A) Main cohort (target accrual: 32 patients) and B) Exploratory cohorts (target accrual: 20 patients), see table-1 below. The primary outcomes include assessment of: 1) Safety and tolerability of CX-5461, in particular to determine late onset ocular toxicity 2) Anti-tumor activity of CX-5461 in patients with solid tumors and germline BRCA2 and/or PALB2 mutation, and 3) Effect of CX-5461 on Quality of Life measures. Secondary outcomes include evaluation of :1) Safety: CTCAE v 5.0, SAEs, dose modifications due to AEs, 2) Activity: best overall response from tumor evaluations performed every 2 cycles, according to RECIST v1.1, and duration of response., and 3) patient-reported outcomes: PRO (PRO-CTCAE v1.0 questionnaires to evaluate cutaneous, gastrointestinal, visual/perceptual, cardio/circulatory, sleep/wake and miscellaneous symptoms. Exploratory Objectives include assessment of: 1) anti-tumor activity of CX-5461 in patients with ovarian cancer and pathogenic/likely-pathogenic BRCA1 mutation and/or other HRD-associated somatic mutation, and 2) molecular profile of tumors and predictive value of mutational signatures in predicting response or resistance to CX-5461. Clinical trial information: NCT04890613. [Table: see text]

Repurposing Itraconazole and Hydroxychloroquine to Target Lysosomal Homeostasis in Epithelial Ovarian Cancer

Drug repurposing is an attractive option for oncology drug development. Itraconazole is an antifungal ergosterol synthesis inhibitor that has pleiotropic actions including cholesterol antagonism, inhibition of Hedgehog and mTOR pathways. We tested a panel of 28 epithelial ovarian cancer (EOC) cell lines with itraconazole to define its spectrum of activity. To identify synthetic lethality in combination with itraconazole, a whole-genome drop-out genome-scale clustered regularly interspaced short palindromic repeats sensitivity screen in two cell lines (TOV1946 and OVCAR5) was performed. On this basis, we conducted a phase I dose-escalation study assessing the combination of itraconazole and hydroxychloroquine in patients with platinum refractory EOC (NCT03081702). We identified a wide spectrum of sensitivity to itraconazole across the EOC cell lines. Pathway analysis showed significant involvement of lysosomal compartments, the trans-golgi network and late endosomes/lysosomes; similar pathways are phenocopied by the autophagy inhibitor, chloroquine. We then demonstrated that the combination of itraconazole and chloroquine displayed Bliss defined synergy in EOC cancer cell lines. Furthermore, there was an association of cytotoxic synergy with the ability to induce functional lysosome dysfunction, by chloroquine. Within the clinical trial, 11 patients received at least one cycle of itraconazole and hydroxychloroquine. Treatment was safe and feasible with the recommended phase II dose of 300 and 600 mg twice daily, respectively. No objective responses were detected. Pharmacodynamic measurements on serial biopsies demonstrated limited pharmacodynamic impact. In vitro, itraconazole and chloroquine have synergistic activity and exert a potent antitumor effect by affecting lysosomal function. The drug combination had no clinical antitumor activity in dose escalation.

Significance

The combination of the antifungal drug itraconazole with antimalarial drug hydroxychloroquine leads to a cytotoxic lysosomal dysfunction, supporting the rational for further research on lysosomal targeting in ovarian cancer.

Research biopsies in patients with gynecologic cancers: patient-reported outcomes, perceptions, and preferences

BACKGROUND

Despite the growing integration of mandatory biopsies for correlative endpoints within oncology clinical trials, there are sparse data on patient-reported outcomes, perceptions, and preferences.

OBJECTIVE

This study aimed to prospectively assess the impact of research biopsies on the quality of life in patients with gynecologic cancer, evaluate patient-reported outcomes, and determine factors associated with patients' willingness to undergo sequential biopsies.

STUDY DESIGN

We conducted a prospective study in patients with gynecologic malignancies undergoing research biopsies between 2015 and 2019 at Princess Margaret Cancer Centre (ClinicalTrials.gov Identifier: NCT02334761). Here, we report the results of the paper-based surveys performed before and 1 week after biopsy. Although the questionnaires each assessed the impact of anxiety using a modified version of the Hospital Anxiety and Depression Scale, the postbiopsy questionnaire specifically assessed the likelihood of future biopsies, postbiopsy symptoms, complications, and perceptions.

RESULTS

A total of 129 patients were enrolled, of which 91 (70.5%) completed at least 1 questionnaire. These patients had either ovarian (89%; 81 of 91) or endometrial cancer (11%; 10 of 91). Of all biopsies taken, 75% were from the abdomen or pelvis (67 of 89). There was 1 clinician-reported complication, a perihepatic hematoma (1%). Pain during the biopsy and physical discomfort were experienced by 60.3% (41 of 68) and 61.8% (42 of 68), respectively. Embarrassment and loss of dignity were experienced by 13.2% (9 of 68) and 11.8% (8 of 68), respectively. Although the mean Hospital Anxiety and Depression Scale score was in the normal range before and after biopsy, there was a significant decline in the total score after the biopsy (prebiopsy, 5.3 [standard deviation, 4.7] vs postbiopsy, 3.7 [standard deviation, 4.5]; P=.005); 84% of subjects (58 of 69) stated that they would definitely or likely consent to another biopsy. There was no impact on patients' willingness for future biopsies based on Eastern Cooperative Oncology Group status, biopsy site, age, number of cores, and pain during the biopsy; however, subjects who reported feeling physically uncomfortable (odds ratio, 0.14; P=.005), embarrassed (odds ratio, 0.03; P=.004) or experienced loss of dignity (odds ratio, 0.05; P=.01) during the biopsy and those who experienced flu-like symptoms (odds ratio, 0.2; P=.018) or felt feverish (odds ratio, 0.2; P=.035) 1 week after biopsy, were less likely to undergo a sequential biopsy. Similarly, those with higher Hospital Anxiety and Depression Scale scores before biopsy (odds ratio, 0.83; P=.008) and after biopsy (odds ratio, 0.8; P=.003) were less likely to consent for another biopsy.

CONCLUSION

Research biopsies were generally well accepted. Most patients (83%) were willing to undergo serial biopsies if necessary. Addressing the potentially modifiable psychosocial aspects of the procedure may improve the experience with research biopsies for patients with gynecologic cancers.

Phase II trial assessing niraparib with or without dostarlimab (anti-PD-1) in recurrent endometrial carcinoma

5574

Background: Treatment options in recurrent endometrial carcinoma (EC) are limited. Endometrioid EC shows alterations in PTEN, a possible biomarker of response to PARP inhibitors (PARPi). Similarly, homologous recombination deficiency (HRd), a biomarker of response to PARPi in ovarian cancer, is associated with serous EC harbouring TP53 mutations. Preclinical EC models have shown synergy between combining a PARPi and immune checkpoint inhibitor (ICI). Methods: A pilot multi-centre, non-randomized, phase II trial enrolled patients (pts) with recurrent serous or endometrioid EC in two consecutive cohorts (NCT03016338). In the first cohort (C1) pts received niraparib 200 or 300 mg qd, based on baseline body weight and platelet count, in 4 week (w) cycles. In the second cohort (C2) niraparib was given with dostarlimab 500 mg q 3 w for 4 cycles, followed by 1000 mg q 6 w thereafter. There was no limit on prior lines of therapy. Prior ICI was not allowed in C2. Primary endpoint was clinical benefit rate (CBR; complete, partial response or stable disease ≥16w). Secondary endpoints included toxicity assessment and ORR. CT scans were performed q 8 w. Potential biomarkers were assessed in archival tissue by IHC (PTEN, p53, MMR, PDL-1 [threshold 1%]) and a NGS panel (including TP53, PTEN, POLE and other HRd genes). Tumour mutational burden-high (TMBh) was defined as top 20% mutation load. Results: In C1, 25 pts were enrolled (23 evaluable for response). Median age was 69 years old, 64% had serous EC, 72% were platinum resistant (PlatR) and median prior therapies was 2 (range 1-4). Median number of cycles was 3. The CBR was 20% (95% CI: 9-39) and median clinical benefit (CB) duration was 5.3 (1.8-7.2) months. The ORR was 1/23 (4%; 0-20). Related grade (g) ≥3 AEs ≥10% were anemia (24%), fatigue (16%) and thrombocytopenia (16%). In C2, 22 pts were enrolled (all evaluable) and two continue on-treatment. Median age was 64 years old, 46% had serous EC, 68% were PlatR and median prior therapies was 2 (1-6). Three pts had MMR deficient (MMRd) tumors (14%) and one pt a POLE mutation (5%). Median number of cycles was 3. The CBR was 31.8% (16-53) and median CB duration was 6.8 months (3.7-9.5). The ORR was 3/22 (14%; 3-35), out of the three responders one had MMRd and one a POLE mutation. Related g≥3 AEs ≥10% were anemia (27%) and neutropenia (14%). No significant correlation was detected between CB and IHC markers (PTEN, p53, MMR, PDL-1), or NGS ( PTEN, TP53, HRd TMBh) in C1 and C2. Conclusions: Niraparib as single agent for treatment in a PlatR enriched recurrent EC population showed modest activity with clinical benefit rate at 16w of 20%. The combination of niraparib and dostarlimab showed a clinical benefit rate at 16w of 31.8% in a predominantly PlatR recurrent EC. PTEN loss by IHC or NGS, and alterations in HRd genes did not correlate with clinical benefit. Clinical trial information: NCT03016338.

Patient self-reporting of tolerability using PRO-CTCAE: A randomized double-blind placebo controlled phase II trial comparing gemcitabine in combination with adavosertib or placebo in women with platinum resistant epithelial ovarian cancer

5541

Background: A 4 month improvement in OS was demonstrated when Wee1 inhibitor adavosertib (Ad) and gemcitabine (G; arm A) was compared to G and placebo (P; arm B) in a phase 2 trial in recurrent ovarian cancer (NCT02151292). The patient reported outcome version of the CTCAE (PRO-CTCAE) was used to capture self-report of the frequency, severity and/or interference (scored 0-4; higher scores indicating worse symptomatic adverse events [syAEs]). Methods: Ad/P was given orally on D1-2, D8-9, D15-16 with G D1, D8, D15 in a 28-day cycle. English speaking pts in 2 centres completed PRO-CTCAE items electronically in clinic at baseline, D1 and D15 of each cycle and off treatment. An exploratory objective was to characterize syAEs in the first 3 months of therapy. We calculated 12-week area under the curve (AUC12w) as a measure of syAE over time and incremental AUC12w (iAUC12w) for adjustment to baseline syAEs and compared arms A and B using an independent samples t-test. We assessed proportion of scores 3-4 at 6 time-points and compared them using Fisher’s Exact Test at each survey. Results: 51 pts were enrolled and completed ≥1 survey, 47 were evaluable for primary outcome (arm A: 28, B: 19). ECOG status was ≤1 in 44/47 pts. Median number of cycles of therapy were 5 (1-16) in arm A, and 2 (1-16) in B. Survey completion rates were high (arm A 93%, B 95%). Mean AUC12w fatigue severity (A 152 [standard error 9] vs B 112 [10]; p = 0.005) and interference (A 144 [11] vs 98 [15]; p = 0.018), diarrhea frequency (A 70 [12] vs B 33 [9]; p = 0.014), mucositis (A 23 [6] vs B 6 [3]; p = 0.012) and difficulty swallowing severity (A 10 [3] vs B 2 [2]; p = 0.023) were higher in arm A (any grade). There were no statistically significant between-arm differences in abdominal pain, bloating, nausea, vomiting and anxiety. The iAUC12w was significantly higher in arm A vs B for difficulty swallowing severity (A 10.1 [3] vs B -2.7 [4.7]; p = 0.02), mucositis severity (A 19.9 [6.6] vs B -3.1 [6.9]; p = 0.02) and fatigue severity (A 35.2 [8.2] vs B -3.1 [9.8]; p = 0.005). Proportions with high scores (3-4) were only significantly higher at C1D15 for fatigue severity in arm A (A 55% vs B 19%, p = 0.044). No significant differences were seen in other 3-4 scores per survey time. Conclusions: This is the first study evaluating pts self-reported toxicity with adavosertib in a randomized setting, allowing pts self-evaluation of toxicity in the context of improved PFS and OS. Greater fatigue, diarrhea, mucositis and difficulty swallowing were experienced by pts receiving adavosertib and gemcitabine, but score 3-4 reached significance on C1D15 fatigue only. No significant differences were detected in syAE profile for nausea, vomiting, abdominal pain, bloating and anxiety. This approach allows objective assessment of pts perception of toxicity with complex therapy. Clinical trial information: NCT02151292.

Adavosertib plus gemcitabine for platinum-resistant or platinum-refractory recurrent ovarian cancer: a double-blind, randomised, placebo-controlled, phase 2 trial

BACKGROUND

The Wee1 (WEE1hu) inhibitor adavosertib and gemcitabine have shown preclinical synergy and promising activity in early phase clinical trials. We aimed to determine the efficacy of this combination in patients with ovarian cancer.

METHODS

In this double-blind, randomised, placebo-controlled, phase 2 trial, women with measurable recurrent platinum-resistant or platinum-refractory high-grade serous ovarian cancer were recruited from 11 academic centres in the USA and Canada. Women were eligible if they were aged 18 years or older, had an Eastern Cooperative Oncology Group performance status of 0-2, a life expectancy of more than 3 months, and normal organ and marrow function. Women with ovarian cancer of non-high-grade serous histology were eligible for enrolment in a non-randomised exploratory cohort. Eligible participants with high-grade serous ovarian cancer were randomly assigned (2:1), using block randomisation (block size of three and six) and no stratification, to receive intravenous gemcitabine (1000 mg/m2 on days 1, 8, and 15) with either oral adavosertib (175 mg) or identical placebo once daily on days 1, 2, 8, 9, 15, and 16, in 28-day cycles until disease progression or unacceptable toxicity. Patients and the team caring for each patient were masked to treatment assignment. The primary endpoint was progression-free survival. The safety and efficacy analysis population comprised all patients who received at least one dose of treatment. The trial is registered with ClinicalTrials.gov, NCT02151292, and is closed to accrual.

FINDINGS

Between Sept 22, 2014, and May 30, 2018, 124 women were enrolled, of whom 99 had high-grade serous ovarian cancer and were randomly assigned to adavosertib plus gemcitabine (65 [66%]) or placebo plus gemcitabine (34 [34%]). 25 women with non-high-grade serous ovarian cancer were enrolled in the exploratory cohort. After randomisation, five patients with high-grade serous ovarian cancer were found to be ineligible (four in the experimental group and one in the control group) and did not receive treatment. Median age for all treated patients (n=119) was 62 years (IQR 54-67). Progression-free survival was longer with adavosertib plus gemcitabine (median 4·6 months [95% CI 3·6-6·4] with adavosertib plus gemcitabine vs 3·0 months [1·8-3·8] with placebo plus gemcitabine; hazard ratio 0·55 [95% CI 0·35-0·90]; log-rank p=0·015). The most frequent grade 3 or worse adverse events were haematological (neutropenia in 38 [62%] of 61 participants in the adavosertib plus gemcitabine group vs ten [30%] of 33 in the placebo plus gemcitabine group; thrombocytopenia in 19 [31%] of 61 in the adavosertib plus gemcitabine group vs two [6%] of 33 in the placebo plus gemcitabine group). There were no treatment-related deaths; two patients (one in each group in the high-grade serous ovarian cancer cohort) died while on study medication (from sepsis in the experimental group and from disease progression in the control group).

INTERPRETATION

The observed clinical efficacy of a Wee1 inhibitor combined with gemcitabine supports ongoing assessment of DNA damage response drugs in high-grade serous ovarian cancer, a TP53-mutated tumour type with high replication stress. This therapeutic approach might be applicable to other tumour types with high replication stress; larger confirmatory studies are required.

FUNDING

US National Cancer Institute Cancer Therapy Evaluation Program, Ontario Institute for Cancer Research, US Department of Defense, Princess Margaret Cancer Foundation, and AstraZeneca.

Manage wisely: poly (ADP-ribose) polymerase inhibitor (PARPi) treatment and adverse events

Poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi) have transformed the treatment landscape in front-line and recurrent high-grade serous ovarian cancer. Maintenance strategies with PARPi have been assessed in randomized phase III trials in ovarian cancer; switch maintenance in the case of olaparib, niraparib, and rucaparib; and concurrent followed by continuation maintenance with veliparib. These studies have shown progression-free survival advantage with PARPi maintenance, with no major adverse changes in the quality of life; however, overall survival data remain immature to date. PARPi have also been incorporated in clinical practice as a single-agent treatment strategy in high-grade serous ovarian cancer, mainly in women who harbor alterations in the BRCA1/2 genes or have alterations in the homologous recombination deficiency (HRD) pathway. Contemporary studies are looking into potentially synergistic combination strategies with anti-angiogenics and immune checkpoint inhibitors, among others. The expansion of PARPi treatment has not been limited to ovarian cancer; talazoparib is licensed in patients with HER2-negative breast cancer with germline BRCA mutations (BRCAm), and front-line olaparib maintenance in patients with pancreatic cancer with germline BRCAm. Numerous studies assessing PARPi either in monotherapy or in combination with other agents are ongoing in multiple tumors, including prostate, endometrial, brain, and gastric cancers. Many patients are being treated with PARPi, some for prolonged periods of time. As a result, a thorough knowledge of the potential short- and long-term adverse events and their management is warranted to improve patient safety, treatment efficacy, and towards maintaining an appropriate dose intensity.

Risk stratified multidisciplinary ambulatory management of malignant bowel obstruction (MAMBO) program for women with gynecological cancers: Preliminary results from a prospective single-center study

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Background: Malignant Bowel Obstruction (MBO) is one of the most common and devastating complications in women with gynecological cancer (GC). There is currently no consensus guideline to improve patient (pt) care in this setting. MAMBO (NCT03260647) is an ongoing prospective study evaluating the clinical implementation of a novel management algorithm for multidisciplinary management of MBO in GC pts. We report preliminary patient outcomes. Methods: All GC pts at Princess Margaret Cancer Centre with a confirmed diagnosis of or are at risk of MBO are eligible for enrollment. Participants follow a low fiber diet titrated by severity of symptom and their monthly weight and albumin levels are recorded, along with standardized patient-reported outcome measures (PROMs) at different time points. For pts who develop MBO, inpatient and ambulatory management algorithms are applied using a multidisciplinary and interprofessional care model consisting of nurses, surgeons, oncologists, radiologists, nutritionists, total parenteral nutrition team, social work, and palliative care. Decisions regarding most optimal management strategies are made by this team with regular MAMBO rounds. A retrospective analysis of pts hospitalized with MBO between 2012 and 2017 was performed in order to have a historical comparison for outcome and survival analysis using Kaplan Meier methods. Results: Since August 2017, 70 pts have been enrolled in MAMBO. Most had high-grade serous ovarian carcinoma (75%), of whom 68% are platinum-resistant. So far, 36 (51%) developed MBO, 6 of whom had multiple sequential episodes. Mean number of days in hospital with MBO was 10 days (median 7, range 0-45), compared to 18 days (median 9, range 0-134) for historical control (p = 0.009). There was no significant loss in weight 6 months from MBO diagnosis but a significant reduction in albumin level by 2.75 g/L after 3 months (p = 0.005). PROMs suggest fatigue and general lack of wellbeing were the symptoms with highest distress. Most patients (78%) received chemotherapy following MBO and most received weekly paclitaxel (36%). Median time from first MBO to death was 219 days (95% CI: 101-not reached) for all-comers in MAMBO and 174 days (95% CI: 98-363) for MBO requiring hospitalization, compared to 108 days (95% CI: 79-160) for historical controls (p = 0.007 and p = 0.062, respectively). Conclusions: Patient care and outcomes from MBO seem to be improved in GC pts enrolled in MAMBO compared to historical controls. Clinical trial information: NCT03260647.

Phase I/II trial assessing hydroxychloroquine and itraconazole in women with advanced platinum-resistant epithelial ovarian cancer (EOC) (HYDRA-01)

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Background: Autophagy is a mechanism of resistance to platinum chemotherapy. Itraconazole (Itr), an antifungal agent, can alter cholesterol-trafficking, leading to accumulation of cholesterol in endosomes/lysosomes and resulting in cancer cell death. Itr is also involved in regulation of angiogenesis, mTOR and Hedgehog pathways. In preclinical studies the Itr effect can be enhanced by combining it with the autophagy inhibitor hydroxychloroquine (H). Drug repurposing studies with Itr have shown a signal of activity in prostate, lung and basal cell carcinoma. Methods: A rolling-6 phase I design was used to enroll patients (pts) with platinum-resistant/refractory EOC. Pts received Itr 300mg twice daily (BID) with H as per dose escalation schedule (range 200mg BID- 600mg BID), continuously in a 28-day cycle. Primary objective was establishment of MTD; secondary objective was objective response rate, progression free survival (PFS). Pre- and on-treatment biopsies were mandatory to evaluate exploratory objectives assessing effect on apoptosis/proliferation, angiogenesis, cholesterol metabolism and mechanism of cytotoxicity. RNAseq and IHC was performed in the sequential biopsies. Results: 11 pts were enrolled, 9 evaluable for efficacy. Histology was high 91% and low-grade serous 9%. Median lines of prior therapy was 7. RP2D was Itr 300mg BID and H 600mg BID. 1 DLT was seen in dose-level 2 was grade 3 hypertension. Other grade ≥3 related toxicity were grade 3 hypokalemia and grade 4 QTc prolongation (1 pt, dose-level 3). No objective responses were observed and 1 pt had stable disease. Median PFS was 1.6 months (1-1.7). Pre- and on-treatment biopsy was available for 10 pts. Increase in autophagy related protein, LC3, P62 and lysosomal marker, LAMP1, expression by IHC was identified in 3 pts. RNAseq revealed no differences between pre and on treatment samples in cholesterol homeostasis, angiogenesis, lysosomal-autophagy, PI3K-mTOR pathways. Conclusions: The combination of Itr and H was feasible but did not show antitumour activity in this heavily pre-treated platinum resistant EOC population. Increase of IHC expression in autophagy related proteins was detected in 30% of pts but did not correlate with patient benefit. Clinical trial information: NCT03081702. [Table: see text]

Optimizing the Care of Malignant Bowel Obstruction in Patients With Advanced Gynecologic Cancer

PURPOSE:

Malignant bowel obstruction (MBO) is a common and distressing complication in women with advanced gynecologic cancer. A pilot, interprofessional MBO program was launched in 2016 at a large Canadian tertiary cancer center to integrate these patients’ complex care needs across multiple disciplines and support women with MBO.

METHOD:

Retrospective analysis to evaluate the outcomes of women with advanced gynecologic cancer who were admitted to hospital because of MBO, before (2014 to 2016: baseline group) and after (2016 to 2018) implementation of the MBO program.

RESULTS:

Of the 169 women evaluated, 106 and 63 were in the baseline group and MBO program group, respectively. Most had ovarian cancer (n = 124; 73%) and had small-bowel obstruction (n = 131; 78%). There was a significantly shorter cumulative hospital length of stay (LOS_sum) within the first 60 days of MBO diagnosis in the MBO program group compared with the baseline group (13 v 22 days, respectively; adjusted P = .006). The median overall survival for women treated in the MBO program was also significantly longer compared with the baseline group (243 v 99 days, respectively; adjusted P = .002). Using the interprofessional MBO care platform, a greater proportion of patients received palliative chemotherapy (83% v 56%) and less surgery (11% v 21%) in the MBO program group than in the baseline group, respectively. A subgroup of women (n = 11) received total parenteral nutrition for longer than 6 months.

CONCLUSION:

Implementation of a comprehensive, interprofessional MBO program significantly affects patient care and may improve outcomes. Unique to this MBO program is an integrated outpatient model of care and education that empowers patients to recognize MBO symptoms for early intervention.

Clinical outcome of sequential chemotherapy after immune checkpoint inhibitors in advanced ovarian cancer

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Background: Immunomodulation through check point inhibition is an important treatment strategy in many cancers. In ovarian cancer (OC) response rates with immune checkpoint inhibitors (ICI) alone are around 10%. Chemotherapy antitumoural effect is driven by cytotoxicity and immunomodulatory effect. ICI treatment reduces tumour induced immune-tolerance improving immunocompetence, essential for chemotherapy effect. We chose to investigate clinical outcomes of chemotherapy post ICI in women with OC. Methods: The Tumor Immunotherapy Program (TIP) database at the Princess Margaret Cancer Centre identified patients with OC treated with chemotherapy after ICI from 2011 to 2018. Evaluation of clinical outcomes including response rate (RR), progression free survival (PFS) and overall survival (OS) was assessed for pre ICI, ICI and post ICI. Results: 40 women with OC were treated with chemotherapy after ICI. 90% had high grade serous histology, 7.5% carcinosarcoma and 2.5% low grade serous. Median number of pre ICI treatment lines was 3 (1-8) and 2 (1-6) in the post ICI setting. Median time of ICI initiation from diagnosis was 3 years. At ICI all patients had PS 0-1 and treated in clinical trials. 2% of the patients had platinum refractory disease, 88% had platinum resistant disease and 10% platinum sensitive disease. 50% were treated with ICI single agent, 16% were treated with ICI combined with chemotherapy, 14% ICI combo and 17% ICI in combination with other agents. Patients were treated for a median of 3 cycles (1-26). 8% experienced PR, 18% SD, no CR were seen. 67% of the patients discontinued treatment due to PD, 25% due to toxicity. Last treatment in pre ICI RR was 35%. First treatment in post ICI RR was 30%. RR for each treatment used in post ICI was 9% for liposomal doxorubicin, 25% for single agent platinum, 29% for weekly paclitaxel and 67% for chemotherapy with bevacizumab. Median PFS in the last pre ICI treatment was 6.5m and 5m in the first post ICI treatment. Median PFS and OS for all the population was 53m and 54m respectively. Conclusions: ICI are associated with modest activity in OC, planned clinical trials exploring systematic sequential therapy integrating ICI, targeted agents and chemotherapy are needed.

Evolve: A post PARP inhibitor clinical translational phase II trial of cediranib-olaparib in ovarian cancer—A Princess Margaret Consortium – GCIG Phase II Trial

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Background: PARP inhibitors (PARPi) are approved therapies in high grade serous ovarian cancer (HGSOC). There are few studies after PARPi progression and correlation with dynamic changes in resistance. We hypothesized that PARPi resistance could be overcome by adding an anti-angiogenic. Methods: We report the first phase 2 trial assessing the combination of olaparib and cediranib after PARPi failure in HGSOC. This investigator initiated study included three cohorts of 10 evaluable patients (pts): i) platinum sensitive post PARPi (PS), ii) platinum resistant post PARPi (PR) and iii) exploratory cohort of pts re-challenged with chemotherapy post PARPi progression (PE) (NCT02681237). The primary objective was to determine objective response rate by RECIST v1.1 and progression free survival (PFS) at 16 weeks. Secondary objectives were to evaluate safety, PFS, overall survival (OS) and mechanisms of PARPi resistance. Pts who had radiographic progression on any PARPi were eligible. Archival tumor at initial diagnosis and baseline tumor biopsy at PARPi progression were mandatory. Pts received olaparib tablets 150mg BID with cediranib 20mg QD until progression or unacceptable toxicity. CT scans were performed every 8 weeks. Whole exome and RNA sequencing were performed on paired tumors tissues. Results: Thirty-four pts were enrolled. BRCA1/2 mutations were found in 9/11 PS, 8/10 PR and 7/13 PE pts. By RECIST1.1, four partial responses were observed (2 in PR and 2 in PE cohorts) and 18 stable disease. The 16−week PFS was 54.5% (31.8−93.6) in PS, 50% (26.9−92.9) in PR and 36% (15.6−82.8) in PE, respectively. OS at 1 year was 81.8% (61.9−100) in PS, 64.8% (39.3−100) in PR and 39.1% (14.7−100) in PE. Main related adverse events were anemia, hypertension, diarrhea and fatigue, grade 3 < 10%. Molecular analyses identified different mechanisms of PARPi resistance in ~77% of evaluable pts with matched pre-post PARPi progression biopsies such as reversion mutations in BRCA1/2 and other homologous repair (HR) genes; BRCA, HR and MDR upregulation, CCNE amplification and RIG-I like receptor downregulation. Conclusions: Treatment with olaparib-cediranib after PARPi failure was feasible and met the predefined bar for efficacy in each cohort. This is the largest clinical trial prospectively evaluating PARPi failure and correlating tissue genomic mechanisms of resistance. Clinical trial information: NCT02681237.

Resisting RECIST-Uniformity Versus Clinical Validity

OBJECTIVES

The Response Evaluation Criteria in Solid Tumors (RECIST) International Working Group developed criteria for tumor response and progression to standardize radiological assessment in patients receiving chemotherapy in phase 2 trials. However, it is unclear whether the defined percentage change in tumor size and volume reflects true clinical benefit for the patient. The RECIST criteria were designed to improve objectivity in trials, but not to replace clinical decision making. The aim of this study was to understand clinicians' opinions about RECIST in current oncology practice.

METHODS

Using Web-based questionnaires, we investigated attitudes to the use of RECIST at a large comprehensive cancer center and in an international group of gynecologic cancer specialists through the Gynecologic Cancer InterGroup. The results reported here relate to the survey focusing on gynecologic cancer.

RESULTS

Sixty medical professionals from 13 countries responded to the survey. The majority of respondents worked at a tertiary or specialist cancer center (51; 86%). Overall, 66% of respondents felt RECIST increased trial objectivity and was a good measure of response. The majority of respondents (81%) reported that they infrequently challenged RECIST evaluation. Overall, 60% felt more than 10% of patients came off trial for clinical rather than radiological progression. In the context of a new small lesion, only 35% felt that should always be considered disease progression. The importance of both clinician and radiologist input was highlighted with nontarget progression. Nontarget progression and target progression were recognized as equally important for clinical decision making (72%).

CONCLUSIONS

RECIST is a key criterion for endpoint assessment in clinical trials with its value recognized by clinicians. However, this survey also highlights the practical limitations of RECIST. Disconnect can be seen between the radiological result and the clinical picture-learning from these patients is critical. Continued efforts to improve metrics assessing patient benefit in trials remains a priority.

Clinical trial of biopsies in oncology: Patient-reported impact (BIOPSY)

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Background: Modest prospective data reports the impact of biopsies on patients (pts) with respect to adverse events (A/E) and anxiety. With increasing use of biopsies in clinical practice and trials, BIOPSY was designed to prospectively assess this. Methods: Pts undergoing a biopsy for diagnosis and/or research at Princess Margaret Cancer Centre were eligible. Surveys at 1 wk prior to biopsy and 1 wk and 1 mth post-biopsy assessed anxiety, A/E and pt experience. Anxiety was measured with a modified hospital anxiety and depression scale (HADS) score. Results: From 3/2015 to 1/2017, 51, 47 and 39 pts completed 1, 2 and 3 surveys respectively. Median age was 61 years. 40 biopsies were for research (78%) and 11 for diagnosis (22%). 46 pts were involved in a clinical trial (90%). 47 pts had a gynecological cancer (92%). 45 pts felt well-informed of the possible risks of the biopsy (88%). 23 pts noted the biopsy would not impact them directly (45%). 48 pts supported the use of tissue for future unrelated research (94%). Feelings of anxiety about the biopsy improved with time (table 1). 28 pts had pain 1 wk post-biopsy (60%) which was a moderate or major problem in 9 pts (19%). 2 pts reported reduced dignity with the biopsy (4%). 12 pts at 1 wk (26%) felt another biopsy would be a moderate-major issue. At 1 mth 3 of these pts reported a biopsy was now a mild problem. No significant A/E occurred. At baseline only 2 pts felt a biopsy would deter them from entering a clinical trial (4%). 42 pts at 1 wk (89%) and 30 pts at 1 mth (77%) felt they would consent to another biopsy for research. On univariate analysis pts with at least moderate pain post-biopsy at 1 wk or 1 mth (p=0.03) or an elevated HADS score at 1 mth (p=0.02) appeared less likely to agree to a further research biopsy but numbers were small. Conclusions: Anxiety and pain are potentially modifiable A/E that impact whether a pt will agree to a further biopsy. Overall, most pts tolerated their biopsy well, supported its use for future unspecified research and were open to further biopsies. [Table: see text]

Somatic BRCA1/2 Recovery as a Resistance Mechanism After Exceptional Response to Poly (ADP-ribose) Polymerase Inhibition

Purpose

Durable and long-term responses to the poly (ADP-ribose) polymerase inhibitor olaparib are observed in patients without BRCA1/2 mutations. However, beyond BRCA1/2 mutations, there are no approved biomarkers for olaparib in high-grade serous ovarian cancer (HGSOC). To determine mechanisms of durable response and resistance to olaparib therapy, we performed an analysis of HGSOC tumors from three patients without germline BRCA1/2 mutations who experienced exceptional responses to olaparib.

Patients and Methods

We performed integrated exome, low-pass genome, and RNA sequence analysis of tumors at diagnosis and upon relapse from patients with platinum-sensitive HGSOC recurrence who were treated > 5 years with olaparib therapy as a single agent.

Results

We observed somatic disruption of BRCA1/2 in all three patients at diagnosis, followed by subsequent BRCA recovery upon progression by copy number gain and/or upregulation of the remaining functional allele in two patients. The third patient with ongoing response (> 7 years) had a tumor at diagnosis with biallelic somatic deletion and loss-of-function mutation, thereby lacking a functional allele for recovery of BRCA1 activity and indicating a potential cure.

Conclusion

Olaparib has durable benefit for patients with ovarian cancer beyond germline BRCA1/2 carriers. These data suggest that biallelic loss of BRCA1/2 in cancer cells may be a potential marker of long-term response to poly (ADP-ribose) polymerase inhibition and that restoration of homologous repair function may be a mechanism of disease resistance.

Ovarian Cancer and BRCA1/2 Testing: Opportunities to Improve Clinical Care and Disease Prevention

Without prevention or screening options available, ovarian cancer is the most lethal malignancy of the female reproductive tract. High-grade serous ovarian cancer (HGSOC) is the most common histologic subtype, and the role of germline BRCA1/2 mutation in predisposition and prognosis is established. Given the targeted treatment opportunities with PARP inhibitors, a predictive role for BRCA1/2 mutation has emerged. Despite recommendations to provide BRCA1/2 testing to all women with histologically confirmed HGSOC, uniform implementation remains challenging. The opportunity to review and revise genetic screening and testing practices will identify opportunities, where universal adoption of BRCA1/2 mutation testing will impact and improve treatment of women with ovarian cancer. Improving education and awareness of genetic testing for women with cancer, as well as the broader general community, will help focus much-needed attention on opportunities to advance prevention and screening programs in ovarian cancer. This is imperative not only for women with cancer and those at risk of developing cancer but also for their first-degree relatives. In addition, BRCA1/2 testing may have direct implications for patients with other types of cancers, many of which are now being found to have BRCA1/2 involvement.