Association between the use of surveillance PET/CT and the detection of potentially salvageable occult recurrences among patients with resected high-risk melanoma

Diagnostic Performance of [18F]F-FDG Positron Emission Tomography (PET) in Non-Ophthalmic Malignant Melanoma: A Systematic Review and Meta-Analysis of More Than 10,000 Melanoma Patients

We described the diagnostic performance of [18F]F-FDG-PET in malignant melanoma by conducting a comprehensive systematic review and meta-analysis of the existing literature. The study was designed following PRISMA-DTA. Original articles with adequate crude data for meta-analytic calculations that evaluated [18F]F-FDG-PET and compared it with a valid reference standard were considered eligible. The pooled measurements were calculated based on the data level (patient/lesion-based). Regarding sub-groups, diagnostic performances were calculated for local, regional and distant involvement. The bivariate model was employed to calculate sensitivity and specificity. The initial search resulted in 6678 studies. Finally, 100 entered the meta-analysis, containing 82 patient-based (10,403 patients) and 32 lesion-based (6188 lesions) datasets. At patient level, overall, [18F]F-FDG-PET had pooled sensitivity and specificity of 81% (95%CI: 73-87%) and 92% (95%CI: 90-94%), respectively. To detect regional lymph node metastasis, the pooled sensitivity and specificity were 56% (95%CI: 40-72%) and 97% (95%CI: 94-99%), respectively. To detect distant metastasis, they were 88% (95%CI: 81-93%) and 94% (95%CI: 91-96%), respectively. At lesion level, [18F]F-FDG-PET had a pooled sensitivity and specificity of 70% (95%CI: 57-80%) and 94% (95%CI: 88-97%), respectively. Thus, [18F]F-FDG-PET is a valuable diagnostic modality for melanoma assessment. It was accurate in various clinical scenarios. However, despite its high specificity, it showed low sensitivity in detecting regional lymph node metastasis and could not replace lymph node biopsy.

Surveillance After a Previous Cutaneous Melanoma Diagnosis: A Scoping Review of Melanoma Follow-Up Guidelines

INTRODUCTION

Cutaneous melanoma accounts for more than 70% of all skin cancer deaths. Follow-up surveillance is an integral part of melanoma patient care, to facilitate early detection of recurrences and subsequent primary melanomas. The purpose of this scoping review is to provide an overview of recently published melanoma surveillance guidelines from regional and national melanoma working groups.

METHODS

A systematic search for relevant studies in MEDLINE and Embase was conducted in September 2022 and was limited to publications from 2010 or later.

RESULTS

A total of 1047 articles were retrieved, and after abstract and full text review, 26 articles from 19 different organizations met inclusion criteria. Life-long annual skin surveillance with a physician was recommended by 53% (9/17) of guidelines. Routine laboratory investigations were recommended by 7/19 guidelines. Regional lymph node ultrasound was recommended by 9/16 guidelines, most often in stage IB or higher, and was optional in 7/16 for patients who met specific criteria. Surveillance with PET-CT or CT and MRI was recommended by 15 and 11 guidelines, respectively, most commonly in stage IIC or higher, with a variable frequency and total duration. Five out of 9 guidelines indicated a preference for skin surveillance to be completed with a dermatologist.

CONCLUSION

Guidelines were highly variable for many aspects of melanoma surveillance, which may be partly attributed to regional differences in healthcare workforce distribution and availability of imaging technologies. Further high-level studies are recommended to provide more evidence on the most effective clinical and imaging follow-up surveillance protocols.

Earlier Recurrence Detection Using Routine FDG PET-CT Scans in Surveillance of Stage IIB to IIID Melanoma: A National Cohort Study of 1480 Patients

BACKGROUND

The effect of routine imaging in melanoma surveillance is unknown. In 2016, Denmark was the first country in the world to implement routine imaging with positron emission tomography-computed tomography with fluorodeoxyglucose (FDG PET-CT) in a nationwide, population-based surveillance program. This study aimed to determine the impact of surveillance with routine FDG PET-CT on hazard, cumulative incidence, and absolute risk of overall, locoregional, and distant recurrence detection in patients with stage IIB to IIID cutaneous melanoma.

METHODS

This retrospective, population-based, nationwide cohort study used prospectively collected data from five national health registries to compare hazard, cumulative incidence, and absolute risk of recurrence in patients with cutaneous melanoma diagnosed in 2008-2010 (cohort 1, followed with clinical examinations) and patients with cutaneous melanoma diagnosed in 2016-2017 (cohort 2, followed with clinical examinations and routine FDG PET-CT at 6, 12, 24, and 36 months).

RESULTS

The study included 1480 patients with stage IIB to IIID cutaneous melanoma. Cumulative incidences of overall and distant recurrence were higher in cohort 2, with a peak difference at three years (32.3 % vs 27.5 % and 25.8 % vs. 18.5 %, respectively). The hazard of recurrence was higher in cohort 2 during the first two years, with hazard rates for overall and distant recurrence of 1.16 (95 % confidence interval [CI], 0.93-1.44) and 1.51 (95 % CI, 1.16-1.96), respectively. The patterns persisted in absolute risk estimates.

CONCLUSIONS

Patients with stage IIB to IIID melanoma followed with routine FDG PET-CT had a 51 % increased hazard of distant recurrence detection within the first two years of surveillance. Future studies must determine whether this earlier recurrence detection translates into improved survival.

Follow-up of primary melanoma patients with high risk of recurrence: recommendations based on evidence and consensus

In spite of the good prognosis of patients with early-stage melanoma, there is a substantial proportion of them that develop local or distant relapses. With the introduction of targeted and immune therapies for advanced melanoma, including at the adjuvant setting, early detection of recurrent melanoma and/or second primary lesions is crucial to improve clinical outcomes. However, there is a lack of universal guidelines regarding both frequency of surveillance visits and diagnostic imaging and/or laboratory evaluations. In this article, a multidisciplinary expert panel recommends, after careful review of relevant data in the field, a consensus- and experience-based follow-up strategy for melanoma patients, taking into account prognostic factors and biomarkers and the high-risk periods and patterns of recurrence in each (sub) stage of the disease. Apart from the surveillance intensity, healthcare professionals should focus on patients' education to perform regular self-examinations of the skin and palpation of lymph nodes.

Precision Nuclear Medicine: The Evolving Role of PET in Melanoma

The clinical management of melanoma patients has been rapidly evolving with the introduction of new targeted immuno-oncology (IO) therapeutics. The current diagnostic paradigms for melanoma patients begins with the histopathologic confirmation of melanoma, initial staging of disease burden with imaging and surgical approaches, treatment monitoring during systemic cytotoxic chemotherapy or IO therapeutics, restaging after completion of adjuvant systemic, surgical, and/or external radiation therapy, and the detection of recurrent malignancy/metastatic disease following therapy. New and evolving imaging approaches with positron-emission tomography (PET) imaging technologies, imaging methodologies, image reconstruction, and image analytics will likely continue to improve tumor detection, tumor characterization, and diagnostic confidence, enabling novel precision nuclear medicine practices for managing melanoma patients. This review will examine current concepts and challenges with existing PET imaging diagnostics for melanoma patients and introduce exciting new opportunities for PET in the current era of IO therapeutics.

Routine PET-CT scans provide early and accurate recurrence detection in asymptomatic stage IIB-III melanoma patients

INTRODUCTION

The use of routine imaging with 18F-FDG PET-CT (PET-CT) in melanoma surveillance is debated and evidence of its diagnostic value and yield in asymptomatic patients is limited. Denmark introduced nationwide routine surveillance with PET-CT in high-risk patients in 2016. The aim of this study was to examine the sensitivity, specificity, negative and positive predictive values, numbers-needed-to-scan and clinical impact of routine PET-CT in the surveillance of asymptomatic stage IIB-III melanoma patients.

MATERIALS AND METHODS

Data was retrieved from the population-based Danish Melanoma Database and patient records. All patients diagnosed with stage IIB-III melanoma at two University Hospitals in 2016 and 2017 were included. Patients underwent surveillance with clinical examinations and PET-CT scans at 6, 12, 24 and 36 months.

RESULTS

In 138 patients, 243 routine PET-CTs were performed within a median follow-up time of 17.7 months. Routine PET-CT detected recurrence at least once in 25 patients (18.1%), including distant recurrence in 19 patients (13.8%). Stage IIB patients had the lowest recurrence rate (11.1%). Numbers-needed-to-scan to detect one distant recurrence was 12.8 patients and median time-to-recurrence was 6.8 months. Sensitivity was 100%, specificity was 94.7% and negative and positive predictive values were 100% and 74.4%, respectively. False positive findings prompted 22 additional investigations (of which ten invasive) in 17 patients (12.3%).

CONCLUSION

Routine PET-CT has a high sensitivity and specificity when used in high-risk melanoma surveillance. Time-to-recurrence and stage-specific recurrence rates indicate high gain of early routine imaging at six months especially for stage IIC and III patients.

Active surveillance of patients who have sentinel node positive melanoma: An international, multi-institution evaluation of adoption and early outcomes after the Multicenter Selective Lymphadenectomy Trial II (MSLT-2)

BACKGROUND

For patients with sentinel lymph node (SLN)-positive cutaneous melanoma, the Second Multicenter Selective Lymphadenectomy trial demonstrated equivalent disease-specific survival (DSS) with active surveillance using nodal ultrasound versus completion lymph node dissection (CLND). Adoption and outcomes of active surveillance in clinical practice and in adjuvant therapy recipients are unknown.

METHODS

In a retrospective cohort of SLN-positive adults treated at 21 institutions in Australia, Europe, and the United States from June 2017 to November 2019, the authors evaluated the impact of active surveillance and adjuvant therapy on all-site recurrence-free survival (RFS), isolated nodal RFS, distant metastasis-free survival (DMFS), and DSS using Kaplan-Meier curves and Cox proportional hazard models.

RESULTS

Among 6347 SLN biopsies, 1154 (18%) were positive and had initial negative distant staging. In total, 965 patients (84%) received active surveillance, 189 (16%) underwent CLND. Four hundred thirty-nine patients received adjuvant therapy (surveillance, 38%; CLND, 39%), with the majority (83%) receiving anti-PD-1 immunotherapy. After a median follow-up of 11 months, 220 patients developed recurrent disease (surveillance, 19%; CLND, 22%), and 24 died of melanoma (surveillance, 2%; CLND, 4%). Sixty-eight patients had an isolated nodal recurrence (surveillance, 6%; CLND, 4%). In patients who received adjuvant treatment without undergoing prior CLND, all isolated nodal recurrences were resectable. On risk-adjusted multivariable analyses, CLND was associated with improved isolated nodal RFS (hazard ratio [HR], 0.36; 95% CI, 0.15-0.88), but not all-site RFS (HR, 0.68; 95% CI, 0.45-1.02). Adjuvant therapy improved all-site RFS (HR, 0.52; 95% CI, 0.47-0.57). DSS and DMFS did not differ by nodal management or adjuvant treatment.

CONCLUSIONS

Active surveillance has been adopted for most SLN-positive patients. At initial assessment, real-world outcomes align with randomized trial findings, including in adjuvant therapy recipients.

LAY SUMMARY

For patients with melanoma of the skin and microscopic spread to lymph nodes, monitoring with ultrasound is an alternative to surgically removing the remaining lymph nodes. The authors studied adoption and real-world outcomes of ultrasound monitoring in over 1000 patients treated at 21 centers worldwide, finding that most patients now have ultrasounds instead of surgery. Although slightly more patients have cancer return in the lymph nodes with this strategy, typically, it can be removed with delayed surgery. Compared with up-front surgery, ultrasound monitoring results in the same overall risk of melanoma coming back at any location or of dying from melanoma.

Performance of Long-Term CT and PET/CT Surveillance for Detection of Distant Recurrence in Patients with Resected Stage IIIA-D Melanoma

BACKGROUND

Follow-up for patients with resected stage IIIA-D melanoma may include computed tomography (CT) or positron emission tomography (PET)/CT imaging to identify distant metastases. The aim of this study was to evaluate the test performance over follow-up time, of structured 6- and 12-monthly follow-up imaging schedules in these patients.

METHODS

We conducted a retrospective analysis of consecutive resected stage IIIA-D melanoma patients from Melanoma Institute Australia (2000-2017). Patients were followed until a confirmed diagnosis of distant metastasis, end of follow-up schedule, or death. Test accuracy was evaluated by cross-classifying the results of the test against a composite reference standard of histopathology, cytology, radiologic imaging, and/or clinical follow-up, and then quantified longitudinally using logistic regression models with random effects.

RESULTS

In total, 1373 imaging tests were performed among 332 patients. Distant metastases were detected in 110 (33%) patients during a median follow-up of 61 months (interquartile range 38-86), and first detected by imaging in 86 (78%) patients. 152 (68%) patients had at least one false-positive result. Sensitivity of the schedule over 5 years was 79% [95% confidence interval (CI) 70-86%] and specificity was 88% (95% CI 86-90%). There was no evidence of a significant difference in test performance over follow-up time or by American Joint Committee on Cancer (AJCC) substage. The positive predictive value ranged between 33 and 48% over follow-up time, reflecting a ratio of 1:2 false-positives per true-positive finding.

CONCLUSIONS

Regular 6- or 12-monthly surveillance imaging using CT or PET/CT has reasonable and consistent sensitivity and specificity over 5-year follow-up for resected stage IIIA-D melanoma patients. These data are useful when discussing the risks and benefits of long-term follow-up.

The utility of initial staging PET-CT as a baseline scan for surveillance imaging in stage II and III melanoma

BACKGROUND

This study evaluates the utility of whole-body PET-CT for the initial staging and subsequent surveillance imaging of patients with completely resected stage II and stage III melanoma.

METHODS

A single-center, retrospective review of patients who received perioperative whole-body PET-CT from January 1, 2005 to December 1, 2019 within three months of initial melanoma diagnosis was performed.

RESULTS

Of 258 total patients with completely resected melanoma who had a PET-CT within 3 months after their melanoma diagnosis, 113 had stage II and 145 had stage III melanoma. PET-CT detected distant metastasis in 3 (2.7%) of 113 stage II patients and 7 (4.8%) of 145 stage III patients. 179 of 258 patients had adequate follow-up time to determine whether they received surveillance cross-sectional imaging and whether they had a melanoma recurrence. 143 (79.9%) received subsequent surveillance imaging, 74 of whom developed a recurrence. In 64 (86.5%) of 74 cases, recurrence was detected by routine surveillance. 26 (34.2%) of 76 stage II and 65 (63.1%) of 103 stage III patients developed a recurrence. The median time to recurrence among the 179 patients for stage II and III was 16.3 and 13.0 months, respectively.

CONCLUSIONS

These findings indicate that baseline staging with whole-body PET-CT rarely provides information that changes initial management. Rather, the value of the initial PET-CT is as a baseline for subsequent surveillance scans. Therefore, it may be premature to discourage cross-sectional imaging for patients with stage II and III melanoma without supportive evidence or a reliable biomarker of recurrent disease.

Cost-effectiveness analysis of PET/CT surveillance imaging to detect systemic recurrence in resected stage III melanoma: study protocol

INTRODUCTION

In the new era of effective systemic therapies for advanced melanoma, early detection of lower volume recurrent disease using surveillance imaging can improve survival. However, intensive imaging follow-up strategies are likely to increase costs to health systems and may pose risks to patients. The objective of this study is to estimate from the Australian health system perspective the cost-effectiveness of four follow-up strategies in resected stage III melanoma over a 5-year period following surgical treatment with curative intent.

METHODS AND ANALYSIS

A decision-analytic model will be built to estimate the costs and benefits of (1) 12 monthly, (2) 6 monthly, (3) 3-4 monthly positron emission tomography/CT imaging for 5 years, compared with (4) no imaging follow-up. The model will be populated with probabilities of disease recurrence, test performance measures using data from >1000 consecutive resected stage III melanoma patients from Melanoma Institute Australia diagnosed between 2000 and 2017. Healthcare resource use, including surveillance imaging, doctor's visits, subsequent tests and procedures to investigate suspicious findings, will be quantified from detailed patient records and valued using Australian reference pricing. Economic outcomes include cost per new distant melanoma recurrence detected and cost per diagnostic error avoided, for no imaging compared with the other strategies.Deterministic sensitivity analyses will examine the robustness of model results.

ETHICS AND DISSEMINATION

This study was approved by the Sydney Local Health District, Sydney Local Health District Ethics Review Committee (RPAH Zone), AU/1/830638 and the Australian Institute of Health and Welfare (EO2019-1-454). The results of this study will be published in peer-reviewed medical and health economics journals and will inform melanoma management guidelines.

The use of FDG-PET/CT to detect early recurrence after resection of high-risk stage III melanoma

BACKGROUND

The role of surveillance imaging in high-risk stage III melanoma patients after complete surgical resection remains controversial, and with the advent of adjuvant therapy, it may also be expanded. Therefore, we evaluated two fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) protocols in two cohorts.

METHODS

Cohort 1 (n = 35) focused on surveillance in asymptomatic patients (before approval and reimbursement of adjuvant therapy) and was assigned to 5x FDG-PET/CT's after surgery: one every 6 months for 2 years, with one final scan after 3 years. Cohort 2 (n = 42) was assigned to one screening FDG-PET/CT, which took place in between surgery and the start of adjuvant treatment.

RESULTS

In cohort 1 (median follow-up: 33 months), 12 patients (34.3%) developed recurrence detected by FDG-PET/CT, of which 7 (20.0%) were detected with the first scan. Sensitivity and specificity were 92.3% and 100%, respectively. In cohort 2, recurrence was suspected on nine scans (21.4%) and four (9.5%) were true positive. The number of scans needed to find one asymptomatic recurrence were 8.8 and 10.5 in cohort 1 and 2, respectively.

CONCLUSIONS

FDG-PET/CT is a valuable imaging tool to detect recurrence in stage III melanoma, even shortly after surgery. A surveillance FDG-PET/CT protocol after surgery or a screening PET/CT before adjuvant therapy should be considered.

Surveillance imaging with FDG-PET/CT in the post-operative follow-up of stage 3 melanoma

Background

As early detection of recurrent melanoma maximizes treatment options, patients usually undergo post-operative imaging surveillance, increasingly with FDG-PET/CT (PET). To assess this, we evaluated stage 3 melanoma patients who underwent prospectively applied and sub-stage-specific schedules of PET surveillance.

Patients and methods

From 2009, patients with stage 3 melanoma routinely underwent PET +/- MRI brain scans via defined schedules based on sub-stage-specific relapse probabilities. Data were collected regarding patient characteristics and outcomes. Contingency analyses were carried out of imaging outcomes.

Results

One hundred and seventy patients (stage 3A: 34; 3B: 93; 3C: 43) underwent radiological surveillance. Relapses were identified in 65 (38%) patients, of which 45 (69%) were asymptomatic. False-positive imaging findings occurred in 7%, and 6% had treatable second (non-melanoma) malignancies. Positive predictive values (PPV) of individual scans were 56%-83%. Negative scans had predictive values of 89%-96% for true non-recurrence [negative predictive values (NPV)] until the next scan. A negative PET at 18 months had NPVs of 80%-84% for true non-recurrence at any time in the 47-month (median) follow-up period. Sensitivity and specificity of the overall approach of sub-stage-specific PET surveillance were 70% and 87%, respectively. Of relapsed patients, 33 (52%) underwent potentially curative resection and 10 (16%) remained disease-free after 24 months (median).

Conclusions

Application of sub-stage-specific PET in stage 3 melanoma enables asymptomatic detection of most recurrences, has high NPVs that may provide patient reassurance, and is associated with a high rate of detection of resectable and potentially curable disease at relapse.

Surveillance imaging for metastasis in high-risk melanoma: importance in individualized patient care and survivorship

Most patients newly diagnosed with melanoma have early-stage disease considered of good prognosis. However, with a risk of recurrence, appropriate follow-up may include surveillance imaging for early relapse detection. Previously, surveillance imaging to detect recurrences was considered unjustified, given the lack of effective treatments. Now, systemic therapies have improved, and patients with low tumor burden may derive benefit from surveillance imaging. Despite this, controversy exists regarding the role of surveillance imaging in early-stage melanoma survivorship, in part reflected by the lack of consensus on specific imaging protocols and broad guidelines. This review discusses published evidence on surveillance imaging to detect metastasis in high-risk melanoma, the need for early recurrence detection and implications for value-based clinical decision-making, survivorship care and multidisciplinary patient management.

Performance of a 31-gene expression profile test in cutaneous melanomas of the head and neck

Background

We report the performance of a gene expression profile test to classify the recurrence risk of cutaneous melanoma tumors of the head and neck as low‐risk Class 1 or high‐risk Class 2.

Methods

Of note, 157 primary head and neck cutaneous melanoma tumors were identified. Survival analyses were performed using Kaplan‐Meier and Cox methods.

Results

Gene expression profile class and node status stratified tumors into significantly different 5‐year survival groups by Kaplan‐Meier method (P < .0001 for all end points), and both were independent predictors of recurrence in multivariate analysis. Overall, 74% of distant metastases and 88% of melanoma‐specific deaths had Class 2 risk.

Conclusion

The gene expression profile test identifies cases at increased risk for metastasis and death independent of a clinically or pathologically negative nodal status, suggesting that incorporation of this molecular tool could improve clinical management of patients with head and neck cutaneous melanoma, especially in those with a negative sentinel lymph node biopsy.

Identification of patients at risk of metastasis using a prognostic 31-gene expression profile in subpopulations of melanoma patients with favorable outcomes by standard criteria

BACKGROUND

A substantial number of patients who relapse and die from cutaneous melanoma (CM) are categorized as being at low risk by traditional staging factors. The 31-gene expression profile (31-GEP) test independently stratifies metastatic risk of patients with CM as low (Class 1, with 1A indicating lowest risk) or high (Class 2,with 2B indicating highest risk).

OBJECTIVE

To assess risk prediction by the 31-GEP test within 3 low-risk (according to the American Joint Committee on Cancer) populations of patients with CM: those who are sentinel lymph node (SLN) negative, those with stage I to IIA tumors, and those with thin (≤1 mm [T1]) tumors.

METHODS

A total of 3 previous validation studies provided a nonoverlapping cohort of 690 patients with 31-GEP results, staging information, and survival outcomes. Kaplan-Meier and Cox regression analysis were performed.

RESULTS

The results included the identification of 70% of SLN-negative patients who experienced metastasis as Class 2, the discovery of reduced recurrence-free survival for patients with thin tumors and Class 2B biology compared with that of those with Class 1A biology (P < .0001); and determination of the 31-GEP test as an independent predictor of risk compared with traditional staging factors in patients with stage I to IIA tumors.

LIMITATIONS

Diagnoses spanned multiple versions of pathologic staging criteria.

CONCLUSIONS

The 31-GEP test identifies high-risk patients who are likely to experience recurrence or die of melanoma within low-risk groups of subpopulations of patients with CM who have SLN-negative disease, stage I to IIA tumors, and thin tumors.

Interim analysis of survival in a prospective, multi-center registry cohort of cutaneous melanoma tested with a prognostic 31-gene expression profile test

BACKGROUND

A 31-gene expression profile (GEP) test that provides risk classification of cutaneous melanoma (CM) patients has been validated in several retrospective studies. The objective of the reported study was a prospective evaluation of the GEP performance in patients enrolled in two clinical registries.

METHODS

Three-hundred twenty two CM patients enrolled in the EXPAND (NCT02355587) and INTEGRATE (NCT02355574) registries met the criteria of age ≥ 16 years, successful GEP result and ≥1 follow-up visit for inclusion in this interim analysis. Primary endpoints were recurrence-free (RFS), distant metastasis-free (DMFS), and overall survival (OS).

RESULTS

Median follow-up was 1.5 years for event-free patients. Median age for subjects was 58 years (range 18-87) and median Breslow thickness was 1.2 mm (range 0.2-12.0). Eighty-eight percent (282/322) of cases had stage I/II disease and 74% (237/322) had a SLN biopsy. Seventy-seven percent (248/322) had class 1 molecular profiles. 1.5-year RFS, DMFS, and OS rates were 97 vs. 77%, 99 vs. 89%, and 99 vs. 92% for class 1 vs. class 2, respectively (p < 0.0001 for each). Multivariate Cox regression showed Breslow thickness, mitotic rate, and GEP class to significantly predict recurrence (p < 0.01), while tumor thickness was the only significant predictor of distant metastasis and overall survival in this interim analysis.

CONCLUSIONS

Interim analysis of patient outcomes from a combined prospective cohort supports the 31-gene GEP's ability to stratify early-stage CM patients into two groups with significantly different metastatic risk. RFS outcomes in this real-world cohort are consistent with previously published analyses with retrospective specimens. GEP testing complements current clinicopathologic features and increases identification of high-risk patients.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02355574  and NCT02355587.