DICE: Dual mTorc Inhibition in advanCed/recurrent Epithelial ovarian cancer resistant to standard treatment-a study protocol for a randomised trial investigating a novel therapy called TAK228.

BACKGROUND: The standard initial treatment for ovarian cancer is surgery and platinum-based chemotherapy and potentially maintenance therapy with avastin or inhibitors of poly-ADP ribose polymerase (PARP). While a proportion of women are cured by this approach, the vast majority will relapse and become resistant to platinum chemotherapy either initially or on subsequent treatment. There is an unmet need to improve response to treatment and quality of life in these women. TAK228 is a novel therapy that can be added to standard treatment in the participant population and the aim of the DICE trial is to assess its effectiveness. Laboratory and clinical research has shown that these ovarian cancers may respond to the molecular target of a drug such as TAK228, and there have been studies using it in other advanced solid tumours including endometrial cancer. METHODS: One hundred twenty-four eligible women will be recruited from participating research sites in the United Kingdom (UK) and Germany. Randomised participants will receive either weekly paclitaxel alone (standard treatment, n = 62) or TAK228 plus weekly paclitaxel (n = 62) until the cancer significantly worsens; there are significant adverse events or any other protocol-defined stopping criteria. Participants will be monitored for response to treatment (using radiological imaging), adverse events and quality of life during both randomised treatment and subsequent follow-up. DISCUSSION: The primary objective/endpoint of the study is to compare the two treatments in terms of progression-free survival, or the length of time that each participant is alive without the cancer significantly worsening according to defined assessment criteria. If the addition of TAK228 to weekly paclitaxel chemotherapy is shown to significantly improve this statistically, and adverse events and quality of life are not significantly worse than standard treatment, then TAK228 plus weekly paclitaxel could potentially be taken forward within the context of a larger phase III trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT03648489 . Registered on 27 August 2018.

Statistical analysis plan for the Dual mTorc Inhibition in advanCed/recurrent Epithelial ovarian, fallopian tube or primary peritoneal cancer (of clear cell, endometrioid and high-grade serous type, and carcinosarcoma) trial (DICE).

BACKGROUND: Treatment for ovarian cancer includes platinum-based chemotherapy, but many women become resistant to chemotherapy, becoming platinum-resistant. Standard of care for these women is weekly paclitaxel chemotherapy, but cancers can often become paclitaxel resistant. TAK228, an investigational dual TORC1/2 inhibitor, is an oral therapy that can be added to standard treatment. The DICE trial is a phase II international multicentre, parallel-group, superiority clinical trial with 1:1, open label randomisation which has the aim of investigating the effectiveness of TAK228 plus weekly paclitaxel. The planned sample size is 124 women (62 per treatment arm) with platinum-resistant ovarian cancer. OBJECTIVE: To outline the planned analyses for DICE in a statistical analysis plan (SAP) before database hard lock and the start of analysis. This ensures that bias is minimised during the analysis phase. RESULTS: This SAP provides detailed descriptions of the analysis principles and statistical procedures for analysing primary and secondary outcomes of the trial. The primary outcome is overall progression-free survival (PFS). Secondary outcomes include progression-free survival (PFS) at 24 weeks, overall response rate (ORR), duration of response (DoR), time to progression (TTP), clinical benefit rate (CBR) at 4 months, Cancer Antigen 125 (CA125) response according to Gynaecological Cancer Intergroup (GCIG) criteria, overall survival (OS), safety and tolerability as assessed by adverse events and the quality-of-life questionnaires (EORTC QLQ-C30 and EORTC QLQ-OV28). This detailed description includes significance levels, sensitivity analyses and compliance analysis. DISCUSSION: The DICE trial will determine whether the addition of TAK228 to weekly paclitaxel chemotherapy shows a statistically significant improvement to participant's progression free and overall survival and that the adverse events (AEs) and quality of life (QoL) are not significantly worse than the standard treatment. The study commenced recruitment in September 2018. An interim analysis was performed in early 2021, the results of which advised continuation of the trial. The study recruitment is ongoing and is due to complete by the end of 2021. TRIAL REGISTRATION: ClinicalTrials.gov NCT03648489 . Registered on 27 August 2018.

Paclitaxel resistance increases oncolytic adenovirus efficacy via upregulated CAR expression and dysfunctional cell cycle control.

Resistance to paclitaxel chemotherapy frequently develops in ovarian cancer. Oncolytic adenoviruses are a novel therapy for human malignancies that are being evaluated in early phase trials. However, there are no reliable predictive biomarkers for oncolytic adenovirus activity in ovarian cancer. We investigated the link between paclitaxel resistance and oncolytic adenovirus activity using established ovarian cancer cell line models, xenografts with de novo paclitaxel resistance and tumour samples from two separate trials. The activity of multiple Ad5 vectors, including dl922-947 (E1A CR2-deleted), dl1520 (E1B-55K deleted) and Ad5 WT, was significantly increased in paclitaxel resistant ovarian cancer in vitro and in vivo. This was associated with greater infectivity resulting from increased expression of the primary receptor for Ad5, CAR (coxsackie adenovirus receptor). This, in turn, resulted from increased CAR transcription secondary to histone modification in resistant cells. There was increased CAR expression in intraperitoneal tumours with de novo paclitaxel resistance and in tumours from patients with clinical resistance to paclitaxel. Increased CAR expression did not cause paclitaxel resistance, but did increase inflammatory cytokine expression. Finally, we identified dysregulated cell cycle control as a second mechanism of increased adenovirus efficacy in paclitaxel-resistant ovarian cancer. Ad11 and Ad35, both group B adenoviruses that utilise non-CAR receptors to infect cells, are also significantly more effective in paclitaxel-resistant ovarian cell models. Inhibition of CDK4/6 using PD-0332991 was able both to reverse paclitaxel resistance and reduce adenovirus efficacy. Thus, paclitaxel resistance increases oncolytic adenovirus efficacy via at least two separate mechanisms - if validated further, this information could have future clinical utility to aid patient selection for clinical trials.