A randomised comparison of treosulfan and carboplatin in patients with ovarian cancer: a study by the Scottish Gynaecological Cancer Trials Group (SGCTG)

Primary platinum resistance and its prognostic impact in patients with recurrent ovarian cancer: an analysis of three prospective trials from the NOGGO study group

Objective

Patients with platinum-resistant ovarian cancer (PROC) have a high need for reliable prognostic markers. Since significance of primary platinum resistance (PPR) versus secondary platinum resistance (SPR) was identified for patients receiving anti-angiogenic therapy, it has not been confirmed for chemotherapy only.

Methods

PROC patients from 3 prospective trials of the NOGGO study group (TOWER, NOGGO-Treosulfan, and TRIAS) were included in this meta-analysis. Exploratory Cox and logistic regression analyses were performed to correlate progression-free survival (PFS) and overall survival (OS) with the timing when platinum resistance developed.

Results

Of 477 patients, 264 (55.3%) were classified as PPR, compared to 213 (44.7%) with SPR. For patients receiving chemotherapy only, SPR was associated with a significantly longer median PFS of 3.9 compared to 3.1 months for PPR (hazard ratio [HR]=0.78; p=0.015). SPR versus PPR was confirmed to be an independent prognostic factor for better PFS in multivariate analysis (HR=0.74; p=0.029). Benefit from adding sorafenib to chemotherapy was mainly seen in PPR (HR=0.40; p<0.001) compared to SPR patients (HR=0.83; p=0.465).

Conclusions

Prognostic significance of SPR versus PPR could be elucidated for patients receiving chemotherapy only. In contrast to bevacizumab, the multi-kinase inhibitor sorafenib exhibits profound therapeutic efficacy in PPR patients indicating potential to overcome this negative prognostic impact.

Measuring Quality of Life in Ovarian Cancer Clinical Trials-Can We Improve Objectivity and Cross Trial Comparisons?

Epithelial ovarian cancer (EOC) remains a lethal disease for the majority of women diagnosed with it worldwide. For the majority of patients, diagnosis occurs late, in the advanced setting. Disease-induced as well as treatment-related adverse events can negatively impact quality of life (QoL). Research to date has captured these data through use of patient-related outcomes (PROs) and, increasingly, has become an area of increased attention and focus in clinical trial reporting. QoL/PRO measurements in EOC clinical trials at different transition points in a patient's journey are increasingly being recognized by patients, clinicians and regulatory agencies as the key determinants of treatment benefit. Various context-specific PROs and PRO endpoints have been described for clinical trials in EOC. Standardized approaches and checklists for incorporating PRO endpoints in clinical trials have been proposed. In a real-world clinical practice setting, PRO/QoL measures, which are meaningful, valid, reliable, feasible and acceptable to patients and clinicians, need to be implemented and used. These may assist by serving as screening tools; helping with the identification of patient preferences to aid in decision making; improving patient-provider communication; facilitating shared decision making. Importantly, they may also improve quality of care through an increasingly patient-centered approach. Potential areas of future research include assessment of anxiety, depression and other mental health issues. In good prognostic groups, such as maintenance clinical trials, following patients beyond progression will capture possible downstream effects related to delaying the psychological trauma of relapse, symptoms due to disease progression and side-effects of subsequent chemotherapy. Identifying PRO endpoints in next-generation-targeted therapies (including immunotherapies) also warrants investigation.

A Systematic Review of Health-Related Quality of Life Reporting in Ovarian Cancer Phase III Clinical Trials: Room to Improve

BACKGROUND

Epithelial ovarian cancer (OC) remains a significant cause of morbidity and mortality for women worldwide. Patients may experience a multitude of disease- and treatment-related symptoms that can impact quality of life (QOL) and should be measured and reported in clinical trials. This systematic review investigated the adequacy of reporting of QOL in randomized phase III trials in OC in both the first-line and recurrent disease setting.

MATERIALS AND METHODS

A systematic review of MEDLINE and EMBASE identified randomized clinical trials of systemic therapy in OC from 1980 to 2014. The adequacy of reporting QOL was evaluated with respect to adherence to established guidelines on reporting QOL in clinical trials and the recent recommendations on the inclusion of patient-reported outcomes in clinical trials from the Fifth Ovarian Cancer Consensus Conference.

RESULTS

Of 3,247 abstracts, 35 studies, including 24,664 patients, met inclusion criteria. Twenty-two trials (63%) were in the first-line setting, with 13 (37%) in the recurrent setting. The inclusion of QOL assessments increased from 2% (1980s) to 62% (2010+). Quality of life was a co-primary endpoint in only one trial.Minimal clinically important differences in QOL were defined in eight trials (23%), with results included in the abstract in 37% and article in 86%. Compliance was reported in 26 trials (74%), with 13 trials (37%) reporting specifically how they dealt with missing data. Only seven trials reported the reasons for missing data (20%).Group results were published in 29 trials (83%), with 6 (17%) reporting individual patient results. Results were more commonly reported as a mean overall score (21 trials; 60%), with specific domain scores in only 9 trials (26%). No studies reported QOL beyond progression or included predefined context-specific endpoints based on objectives of treatment (i.e., palliation/cure/maintenance) and the patient population. Duration of benefit of palliative chemotherapy was reported in only one study.

CONCLUSION

Inclusion and reporting of QOL as a trial endpoint has improved in phase III trials in OC, but there are still significant shortfalls that need to be addressed in future trials.

IMPLICATIONS FOR PRACTICE

The impact of treatment on quality of life (QOL) is an important consideration in patients with ovarian cancer for whom treatment is often given with palliative intent. Both the disease and treatment impact a patient's QOL and require careful evaluation in clinical trials. Matching the QOL questions to the patient population of interest is critical. Similar rigor to that used to assess progression-based endpoints is essential to guide clinical decisions. This systematic review demonstrated that although the inclusion and reporting of QOL as a trial endpoint has improved in phase III trials there are still significant shortfalls that need to be addressed in future trials.

Patient-reported outcomes (PRO) in ovarian cancer clinical trials-lost opportunities and lessons learned

Despite increased recognition of the value of including patient-reported outcomes (PROs) as important end points in phase III clinical trials, there has been a lack of pre-specified PRO hypotheses and shortcomings with the analyses and interpretation of PROs in many ovarian cancer trials. This paper discusses and provides examples of the so-called lost opportunities in ovarian cancer trials. These include: (i) no clear pre-specified PRO hypotheses; (ii) PRO end points not included; (iii) insensitive PRO end point selection; (iv) collection of poor-quality PRO data not suitable for analysis; (v) differences in PROs between treatment arms ignored; and (vi) poor reporting quality. We can learn from the past and with relatively little additional effort, improve the collection and interpretation of PRO data in future ovarian cancer trials. The importance of doing so is underpinned by recent initiatives to improve the standard and usefulness of PRO data in clinical trials. These include the Food and Drug Administration (FDA) Guidance for PROs to support labelling claims, the European Society for Medical Oncology Magnitude of Clinical Benefit Scale (ESMO MCBS), the International Society for Quality-of-Life Research PRO reporting guidance and the Consolidated Standards of Reporting Clinical Trials (CONSORT)-PRO-extension statement which includes a checklist of recommended items to include in PRO sections of trial protocols. Promoting the importance of hypothesis-driven PROs in ovarian cancer clinical trials will lead to improvements in the design of these trials and the interpretation of their results.

A phase III, open label, randomized multicenter controlled trial of oral versus intravenous treosulfan in heavily pretreated recurrent ovarian cancer: a study of the North-Eastern German Society of Gynecological Oncology (NOGGO)

OBJECTIVE

In recurrent ovarian cancer (ROC), there is a high demand on effective therapies with a mild toxicity profile. Treosulfan is an alkylating agent approved as oral (p.o.) and intravenous (i.v.) formulation for the treatment of recurrent ovarian cancer. Data on safety and efficacy for either formulation are rare. For the first time we conducted a randomized phase III study comparing both formulations in women with ROC.

METHODS

Patients having received at least two previous lines of chemotherapy were randomly assigned to one of two treatment arms: treosulfan i.v. 7000 mg/m² d1 q4w or treosulfan p.o. 600 mg/m² d1-28 q8w. Primary endpoint was safety regarding hematological and gastrointestinal toxicity grade III/IV, secondary endpoints were other toxicities, clinical benefit rate (CBR), time to progression (TTP), overall survival (OS) and quality of life.

RESULTS

250 patients were treated with treosulfan i.v. (128) or treosulfan p.o. (122). In general treosulfan therapy was well tolerated in both treatment arms. Leukopenia grade III/IV occurred significantly more frequently in the p.o. arm (3.9% i.v. arm, 14.8% p.o. arm, p = 0.002). Other toxicities were similar in both arms. CBR was comparable between arms (41.4% i.v. arm, 36.9% p.o. arm). No difference in TTP (3.7 months i.v. arm, 3.5 months p.o. arm) or OS (13.6 months i.v. arm, 10.4 months p.o. arm, p = 0.087) occurred.

CONCLUSIONS

Given the safety and efficacy results treosulfan is an acceptable option for heavily pretreated OC patients. Regarding the toxicity profile the i.v. application was better tolerated with less grade III and IV toxicities.

A phase II study to determine the efficacy and safety of oral treosulfan in patients with advanced pre-treated Ewing sarcoma ISRCTN11631773

We report a prospective Phase II study of efficacy and toxicity for oral treosulfan in advanced Ewing sarcoma. Twenty patients, median age 19 years (range 7-39) from five UK sites, were treated with oral treosulfan 1 g/m(2) daily for 7 days in 28. Primary endpoint was objective response rate. Best response was stable disease in one patient. All patients died of progressive disease, after median 6.41 months. Median progression free survival was 1.8 months. Toxicity was minimal. No activity was demonstrated for treosulfan at this dose. Progression free survival data should be able to be used for comparison when planning future clinical trials.

Estimation of expectedness: predictive accuracy of standard therapy outcomes in randomized phase 3 studies in epithelial ovarian cancer

BACKGROUND

The anticipated clinical outcome of the standard/control arm is an important parameter in the design of randomized phase 3 (RP3) trials to properly calculate sample size, power, and study duration. Changing patterns of care or variation in the study population enrolled may lead to a deviation from the initially anticipated outcome. The authors hypothesized that recent changes in patterns of care in epithelial ovarian cancer (EOC) have led to challenges in correctly estimating the outcome of control groups.

METHODS

A systematic review of the literature was conducted for RP3 trials of EOC published between January 2000 and December 2010. The expected outcome of the control arm as well as the actual outcome achieved by this cohort was collected and a ratio (actual‐over‐expected ratio) was calculated. The estimation of outcome was deemed accurate if the outcome of the control arm was between 0.75 to 1.25 times the anticipated outcome.

RESULTS

A total of 35 trials were eligible for analysis. Fifteen trials had survival as the primary endpoint whereas 20 had a progression‐based primary endpoint. In total, 12 of 15 trials with a survival‐based endpoint significantly underestimated the outcome of the control arm, whereas only 4 of 20 trials with a progression‐based endpoint did. Studies with a survival endpoint underestimated outcome more frequently than those with a progression endpoint (P<.001).

CONCLUSIONS

Survival of the control arm has frequently been underestimated in recent EOC RP3 trials. This underestimation means that the initial statistical assumptions of these trials may have been inaccurate. Underestimating the outcome of the control arm may result in trials being underpowered to demonstrate the absolute benefit they were designed to show. Cancer 2015;121:413–422. © 2014 American Cancer Society.

The anticipated clinical outcome of the standard/control arm is an important parameter in the design of randomized phase 3 trials for the accurate calculation of sample size, power, and study duration but is often underestimated in ovarian cancer trials. Changing patterns of care and variations in enrolled study populations may result in a deviation from the anticipated outcome and subsequent inaccurate statistical assumptions.

A prospective multicenter study of treosulfan in elderly patients with recurrent ovarian cancer: results of a planned safety analysis

BACKGROUND

Treosulfan, an alkylating agent, has demonstrated activity in recurrent ovarian carcinoma. It is equieffective as oral (p.o.) and intravenous (i.v.) formulation. To explore the preference and compliance of elderly patients regarding p.o. or i.v. treosulfan for the treatment of relapsed ovarian carcinoma, women aged 65 years or older were included in this prospective multicenter study. Since elderly patients usually have several concomitant diseases and experience more treatment toxicity, an interim safety analysis was planned and performed after 25 patients finished therapy to assess the tolerability of the treatment regimens.

METHODS

Patients had a free choice of treosulfan i.v. (7,000 mg/m(2) day 1 of a 28-day cycle) or p.o. (600 mg/m(2) day 1-28 of a 56-day cycle) for a maximum of 12 cycles (i.v.) or 12 months (p.o.). Indecisive patients were randomized. Toxicity was evaluated according to the NCI-CTC version 2.0.

RESULTS

Twenty-five of 51 recruited patients completed therapy at the time of the planned interim analysis (median age, 75 years; range, 70-82). Median ECOG was 1, and median number of prior chemotherapy regimens was 2. A median number of 4 cycles (range, 1-12) were administered per patient. Anemia was the most common hematological toxicity (88 % of patients). Most frequent non-hematological toxicities were nausea (76 %), constipation (68 %), and fatigue (64 %).

CONCLUSION

Treatment was generally well tolerated despite the fact that most patients suffered from multiple comorbidities and were heavily pretreated. There were no unexpected hematological or non-hematological toxicities. Based on this safety analysis, the next step of study recruitment was continued.

The use of treosulfan and gemcitabine in the treatment of platinum-resistant ovarian cancer

The combination of treosulfan and gemcitabine (TG) has been shown to have activity in ovarian cancer. These two agents are thought to be synergistic, with gemcitabine causing the persistence of treosulfan-induced DNA crosslinks. This study aimed to investigate the response rates, survival and toxicity in patients with platinum-resistant ovarian cancer treated with TG. A retrospective case note review of the patients treated with TG was performed in one cancer centre between May 1st, 2000 and November 1st, 2005. Estimates of cumulative survival were obtained using the Kaplan-Meier method. Forty-nine patients were identified; median age at diagnosis was 55 years (range, 31-72) and the median follow-up was 45.1 months (range, 12.2-118.3). TG was used as second-, third-, fourth- and fifth-line chemotherapy in 15, 19, 13 and 2 patients, respectively. Fifteen patients (30.6%) had stable disease; 25 (51%), a partial response; 1 (2%), a complete response and 8 (16.3%) had progressive disease. Median survival following diagnosis was 45.1 months and the median relapse-free survival was 12 months. The median survival time from the start of TG was 13.7 months with a relapse-free survival of 6.3 months. The median number of cycles given was 7. The most common toxicity recorded was myelosuppression. There were no treatment-related deaths. TG chemotherapy produced favourable response rates in a heavily pre-treated group of patients with platinum-resistant epithelial ovarian cancer. This doublet warrants further investigation in a phase III trial setting.

Stopping a trial early in oncology: for patients or for industry?

BACKGROUND

The aim of this study is to assess the use of interim analyses in randomised controlled trials (RCTs) testing new anticancer drugs, focussing on oncological clinical trials stopped early for benefit.

MATERIALS AND METHODS

All published clinical trials stopped early for benefit and published in the last 11 years, regarding anticancer drugs and containing an interim analysis, were assessed.

RESULTS

Twenty-five RCTs were analysed. The evaluation of efficacy was protocol planned through time-related primary end points, >40% of them overall survival. In 95% of studies, at the interim analysis, efficacy was evaluated using the same end point as planned for the final analysis. As a consequence of early stopping after the interim analysis, approximately 3300 patients/events across all studies were spared. More than 78% of the RCTs published in the last 3 years were used for registration purposes.

CONCLUSION

Though criticism of the poor quality of oncological trials seems out of place, unfortunately early termination raises new concerns. The relation between sparing patients and saving time and trial costs indicates that there is a market-driven intent. We believe that only untruncated trials can provide a full level of evidence which can be translated into clinical practice without further confirmative trials.