Survival Benefit Associated With Participation in Clinical Trials of Anticancer Drugs: A Systematic Review and Meta-Analysis

Importance

Many cancer clinical investigators view clinical trials as offering better care for patients than routine clinical care. However, definitive evidence of clinical benefit from trial participation (hereafter referred to as the participation effect) has yet to emerge.

Objective

To conduct a systematic review and meta-analysis of the evidence examining whether patient participation in cancer trials was associated with greater survival benefit compared with routine care.

Data Sources

Studies were found through PubMed and Embase (January 1, 2000, until August 31, 2022), as well as backward and forward citation searching.

Study Selection

Studies were included that compared overall survival of trial participants and routine care patients.

Data Extraction and Synthesis

Data extraction and methodological quality assessment were completed by 2 independent coders using Covidence software. Data were pooled using a random-effects model and analyzed based on the quality of the comparison between trial participants and routine care patients (ie, extent to which studies controlled for bias and confounders).

Main Outcomes and Measures

The hazard ratio (HR) for overall survival of trial participants vs routine care patients.

Results

Thirty-nine publications were included, comprising 85 comparisons of trial participants and routine care patients. The meta-analysis revealed a statistically significant overall survival benefit for trial participants (HR, 0.76 [95% CI, 0.69-0.82]) when all studies were pooled, regardless of design or quality. However, survival benefits diminished in study subsets that matched trial participants and routine care patients for eligibility criteria (HR, 0.85 [95% CI, 0.75-0.97]) and disappeared when only high-quality studies were pooled (HR, 0.91 [95% CI, 0.80-1.05]). They also disappeared when estimates were adjusted for potential publication bias (HR, 0.94 [95% CI, 0.86-1.03]).

Conclusions and Relevance

Many studies suggest a survival benefit for cancer trial participants. However, these benefits were not detected in studies using designs addressing important sources of bias and confounding. Pooled results of high-quality studies are not consistent with a beneficial effect of trial participation on its own.

Factors associated with clinical trial participation for patients with renal cell carcinoma

OBJECTIVE

Recruitment of a diverse and representative study population is critical to the external validity of oncology clinical trials. The primary objective of this study was to characterize the factors associated with clinical trial participation for patients with renal cell carcinoma and the secondary objective was to examine differences in survival outcomes.

MATERIALS AND METHODS

We used a matched case-control design by querying the National Cancer Database for patients with renal cell carcinoma who were coded as having enrolled in a clinical trial. Trial patients were matched in a 1:5 ratio to the control cohort based on clinical stage and then sociodemographic variables were compared between the 2 groups. Multivariable conditional logistic regression models evaluated factors associated with clinical trial participation. The trial patient cohort was then matched again in a 1:10 ratio based on age, clinical stage, and comorbidities. Log-rank test was used to compare overall survival (OS) between these groups.

RESULTS

From 2004 to 2014, 681 patients enrolled in clinical trials were identified. Clinical trial patients were significantly younger and had a lower Charlson-Deyo comorbidity score. On multivariate analysis, male patients and white patients were more likely to participate compared to their Black counterparts. Having Medicaid or Medicare negatively associated with trial participation. Median OS was greater among clinical trial participants.

CONCLUSION

Patient sociodemographic factors remain significantly associated with clinical trial participation and trial participants experienced superior OS to their matched counterparts.

Clinical Research Professional Providing Care Coordination Support: A Study of Hawaii Minority/Underserved NCORP Community Site Trial Participants

PURPOSE

Although effective care coordination (CC) is recognized as a vital component of a patient-centered, high-quality cancer care delivery system, CC experiences of patients who enroll and receive treatment through clinical trials (CTs) are relatively unknown. Using mixed methods, we examined perceptions of CC among patients enrolled onto therapeutic CTs through the Hawaii Minority/Underserved National Cancer Institute Community Oncology Research Program.

METHODS

The Care Coordination Instrument, a validated instrument, was used to measure patients' perceptions of CC among CT participants (n = 45) and matched controls (n = 45). Paired t-tests were used to compare overall and three CC domain scores (Communication, Navigation, and Operational) between the groups. Semistructured focus group interviews were conducted virtually with 14 CT participants in 2020/2021.

RESULTS

CT participants reported significantly higher total CC scores than non-CT participants (P = .0008). Similar trends were found for Navigation and Operational domain scores (P = .007 and .001, respectively). Twenty-nine percent of CT participants reported receiving high-intensity CC assistance from their clinical research professionals (CRPs). Content analysis of focus group discussions revealed that nearly half of the focus group discussions centered on CRPs (47%), including CC support provided by CRPs (26%). Other key themes included general CT experiences (22%) and CRP involvement as an additional benefit to CT participation (15%).

CONCLUSION

Our results show that patients on CTs in this study had a more positive CC experience. This may be attributable in part to CC support provided by CRPs. These findings highlight both the improved experience of treatment for patients participating in a trial and the generally unrecognized yet integral role of CRPs as part of a cancer CT care team.

Quantifying geographical accessibility to cancer clinical trials in different income landscapes

Background

Clinical trials are increasingly perceived as a therapeutic opportunity for cancer patients. Favoring their concentration in few high-expertise academic centers maximizes quality of data collection but poses an issue of access equality. Analytical tools to quantify trial accessibility are needed to rationalize resources.

Materials and methods

We constructed a distance-based accessibility index (dAI) using publicly available data on demographics, cancer incidence and trials. Multiple strategies were applied to mitigate or quantify clear sources of bias: reporting biases by text mining multiple registries; reliability of simple geographical distance by comparison with high-quality travel cost data for Italy; index inflation due to highly heterogeneous cancer incidence by log-transformation. We studied inequalities by Gini index and time trend significance by Mann–Kendall test. We simulated different resource allocation models in representative countries and identified locations where new studies would maximally improve the national index.

Results

The dAI approximated well a more realistic but not widely applicable travel cost-based index. Accessibility was unevenly distributed across and within countries (Gini index ∼0.75), with maximal inequalities in high- and upper-middle-income countries (China, United States, Russian Federation). Over time, accessibility increased but less than the total number of trials, most evidently in upper-middle-income countries. Simulations in representative countries (Italy and Serbia) identified ideal locations able to maximally raise the national index.

Conclusions

Access to clinical trials is highly uneven across and within countries and is not mitigated by simple increase in the number of trials; a rational algorithmic approach can be used to mitigate inequalities.

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Accessibility to cancer clinical trials grew less than total number of trials over time in upper-middle-income countries.

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Accessibility is unevenly distributed, with maximal inequalities in high- and upper-middle-income countries.

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Simulation of resource allocation can identify ideal locations able to raise the national accessibility index.

Factors associated with enrolment in clinical trials among women with early-stage breast cancer

Background

Clinical trials allow development of innovative treatments and ameliorate the quality of clinical care in oncology. Data show that only a minority of patients are enrolled in clinical trials. We assessed enrolment in clinical trials and its correlates among women with early breast cancer.

Methods

We included 9516 patients with stage I-III breast cancer from the multicenter, prospective CANTO study (NCT01993498), followed-up until year 4 (Y4) post-diagnosis. We assessed factors associated with enrolment using multivariable logistic regression. In exploratory, propensity score matched analyses, we used multiple linear regression to evaluate the relationship of enrolment in clinical trials with the European Organisation for Research and Treatment of Cancer Quality Of Life (QoL) questionnaire (EORTC QLQ-C30) Summary Score and described clinical outcomes (distant disease event, invasive disease event, and death by any cause) according to enrolment.

Results

Overall, 1716 patients (18%) were enrolled in a clinical trial until Y4 post-diagnosis of breast cancer. Socioeconomic factors were not associated with enrolment. Centres of intermediate volume were most likely to enrol patients in clinical trials [versus low volume, odds ratio 1.45 (95% confidence interval (CI) 1.08-1.95), P = 0.0124]. Among 2118 propensity score matched patients, enrolment was associated with better QoL at Y4 (adjusted mean difference versus not enrolled 1.37, 95% CI 0.03-2.71, P = 0.0458), and clinical outcomes (enrolled versus not enrolled, distant disease event 7.3% versus 10.1%, P = 0.0206; invasive disease event 8.2% versus 10.5%, P = 0.0732; death by any cause 2.8% versus 3.7%, P = 0.2707).

Conclusions

In this large study, one in five patients enrolled on a clinical trial until Y4 after diagnosis of early breast cancer. Geographical and centre-related factors were significantly associated with enrolment in clinical trials. Inclusion in clinical trials seemed associated with improved QoL and clinical outcomes. Access to innovation for early-stage breast cancer patients should be encouraged and facilitated by overcoming organizational and geographical barriers to recruitment.

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The proportion of patients who access innovation through participation in clinical trials is generally limited.

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Rate of enrolment in clinical trials among women with early breast cancer exceeded what previously found in other settings.

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Clinical and geographical factors were associated to access to innovation in clinical trials.

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Enrolment in clinical trials is associated with better quality of life and clinical outcomes.

Testing for EGFR Mutations and ALK Rearrangements in Advanced Non-Small-Cell Lung Cancer: Considerations for Countries in Emerging Markets

The treatment of patients with advanced non-small-cell lung cancer (NSCLC) in recent years has been increasingly guided by biomarker testing. Testing has centered on driver genetic alterations involving the epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) rearrangements. The presence of these mutations is predictive of response to targeted therapies such as EGFR tyrosine kinase inhibitors (TKIs) and ALK TKIs. However, there are substantial challenges for the implementation of biomarker testing, particularly in emerging countries. Understanding the barriers to testing in NSCLC will be key to improving molecular testing rates worldwide and patient outcomes as a result. In this article, we review EGFR mutations and ALK rearrangements as predictive biomarkers for NSCLC, discuss a selection of appropriate tests and review the literature with respect to the global uptake of EGFR and ALK testing. To help improve testing rates and unify procedures, we review our experiences with biomarker testing in China, South Korea, Russia, Turkey, Brazil, Argentina and Mexico, and propose a set of recommendations that pathologists from emerging countries can apply to assist with the diagnosis of NSCLC.

Impact of Clinical Trial Participation on Survival of Patients with Metastatic Non-Small Cell Lung Cancer

INTRODUCTION

The impact of clinical trial participation on overall survival is unclear. We hypothesized that enrollment in a therapeutic drug clinical trial is associated with longer overall survival in patients with metastatic non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

We linked electronic medical record and Washington State cancer registry data to identify patients with metastatic NSCLC diagnosed between January 1, 2007, and December 31, 2015 who received treatment at a National Cancer Institute-designated cancer center. The exposure was trial enrollment. The primary outcome was overall survival, defined as the date of second-line treatment initiation to date of death or last follow-up. We used a conditional landmark analysis starting at the date of second-line treatment initiation and propensity scores with inverse probability of treatment weighting to estimate the association between trial enrollment and survival.

RESULTS

Of 215 patients, 40 (19%) participated in a second-line trial. Trial participants were more likely to be never smokers (45% vs 27%), have a good performance status (88% vs 77%) and have EGFR (48% vs 14%) and ALK mutations (8% vs 5%) than nonparticipants. Trial participants had similar overall survival to nonparticipants (HR 1.05; 95% CI, 0.72, 1.53; p = 0.81) after adjusting for sociodemographic and disease characteristics.

CONCLUSION

Accounting for the immortal time bias and selection bias, trial participation does not appear detrimental to survival. This finding may be reassuring to patients and supports programs and policies to improve clinical trial access.

STRA6 Polymorphisms Are Associated With EGFR Mutations in Locally-Advanced and Metastatic Non-Small Cell Lung Cancer Patients

Retinol plays a significant role in several physiological processes through their nuclear receptors, whose expression depends on retinol cytoplasmic concentration. Loss of expression of nuclear receptors and low retinol levels have been correlated with lung cancer development. Stimulated by retinoic acid 6 (STRA6) is the only described cell membrane receptor for retinol uptake. Some chronic diseases have been linked with specific polymorphisms in STRA6. This study aimed to evaluate four STRA6 single nucleotide polymorphisms (SNPs) (rs4886578, rs736118, rs351224, and rs97445) among 196 patients with locally-advanced and metastatic non-small cell lung cancer (NSCLC) patients. Genotyping, through a validated SNP assay and determined using real time-PCR, was correlated with clinical features and outcomes. NSCLC patients with a TT SNP rs4886578 and rs736118 genotype were more likely to be >60 years, non-smokers, and harboring EGFR mutations. Patients with a TT genotype compared with a CC/CT SNP rs974456 genotype had a median progression-free survival (PFS) of 3.2 vs. 4.8 months, p = 0.044, under a platinum-based regimen in the first-line. Furthermore, patients with a TT rs351224 genotype showed a prolonged overall survival (OS), 47.5 months vs. 32.0 months, p = 0.156. This study showed a correlation between clinical characteristics, such as age, non-smoking history, and EGFR mutational status and oncological outcomes depending on STRA6 SNPs. The STRA6 TT genotype SNP rs4886578 and rs736118 might be potential biomarkers in locally-advanced and metastatic NSCLC patients.

Brigatinib in ALK-positive non-small cell lung cancer: real-world data in the Latin American population (Bri-world extend CLICaP)

Background: Brigatinib has demonstrated its efficacy as first-line therapy and in further lines for ALK-positive non-small cell lung cancer (NSCLC) patients; however, real-world data in Latin America are scarce. Methods: From January 2018 to March 2020, 46 patients with advanced ALK-positive NSCLC received brigatinib as second or further line of therapy in Mexico and Colombia. The primary end point was progression-free survival (PFS); secondary end point was time to treatment discontinuation (TTD). Results: At a median follow-up of 9.3 months, the median PFS was 15.2 months (95% CI: 11.6-18.8), and TTD was 18.46 months (95% CI: 9.54-27.38). The estimated overall survival at 12 months was 80%. Safety profile was consistent with previously published data. Conclusion: Brigatinib is an effective treatment for previously treated ALK-positive NSCLC patients in a real-world setting.

Are cancer patients better off if they participate in clinical trials? A mixed methods study

Background

Research and cancer care are closely intertwined; however, it is not clear whether physicians and nurses believe that clinical trials offer the best treatment for patients and, if so, whether this belief is justified. The aim of this study was therefore: (i) to explore how physicians and nurses perceive the benefits of clinical trial participation compared with standard care and (ii) whether it is justified to claim that clinical trial participation improves outcomes for cancer patients.

Methods

A mixed methods approach was used employing semi-structured interviews with 57 physicians and nurses in oncology and haematology and a literature review of the evidence for trial superiority, i.e. the idea that receiving treatment in a clinical trial leads to a better outcome compared with standard care. Inductive thematic analysis was used to examine the interview data. A literature review comprising nine articles was conducted according to a conceptual framework developed by Peppercorn et al. and evaluated recent evidence on trial superiority.

Results

Our findings show that many physicians and nurses make claims supporting trial superiority, however very little evidence is available in the literature comparing outcomes for trial participants and non-participants that supports their assertions.

Conclusions

Despite the recent rapid development and use of targeted therapy and immunotherapy, we find no support for trial participation to provide better outcomes for cancer patients than standard care. Hence, our present results are in line with previous results from Peppercorn et al. A weaker version of the superiority claim is that even if a trial does not bring about a direct positive effect, it brings about indirect positive effects. However, as the value of such indirect effects is dependent on the individual’s specific circumstances and preferences, their existence cannot establish the general claim that treatment in trials is superior. Belief in trial superiority is therefore unfounded. Hence, if such beliefs are communicated to patients in a trial recruitment context, it would provide misleading information. Instead emphasis should be on patients volunteering to give an altruistic contribution to the furthering of knowledge and to the potential benefit of future patients.

Clinical trial participation and aggressive care at the end of life in patients with ovarian cancer

OBJECTIVES

In non-gynecologic cancers, clinical trial participation has been associated with aggressive care at the end of life. The objective of this investigation was to examine how trial participation affects end of life outcomes in patients with ovarian cancer.

METHODS

In a retrospective review of women diagnosed with ovarian cancer at our institution between January 2010 and December 2015, we collected variables identified by the National Quality Forum as measures of aggressive end of life care including chemotherapy in the last 14 days of life, intensive care unit (ICU) admission in the last 30 days of life, or death in the acute care setting. Trials investigating medications but not surgical interventions were included. The primary outcome of this study was the association between trial participation and the National Quality Forum measures of aggressive end of life care in ovarian cancer decedents. Data were analyzed with univariable and multivariable parametric and non-parametric testing, and time to event outcomes were analyzed using the Kaplan-Meier method and Cox's proportional hazard models.

RESULTS

Among 391 women treated for ovarian cancer, 62 patients (16%) participated in a clinical trial. Patients enrolled in clinical trials were more likely to have chemotherapy administered within 14 days of death; however, no association was found with other metrics of aggressive care at the end of life including the initiation of a new chemotherapy regimen in the last 30 days of life, ICU admissions, and death in an acute care setting. Among patients with recurrent ovarian cancer, median overall survival for trial participants was 57 months compared with only 31 months in non-trial participants (p<0.001).

CONCLUSIONS

In patients with ovarian cancer, clinical trial enrollment is associated with chemotherapy administration within 14 days of death, but not other measures of aggressive care at the end of life. Given the importance of clinical trial participation in improving care for women with ovarian cancer, this study suggests that concerns regarding aggressive care prior to death should not limit clinical trial participation.

Radical consolidative treatment provides a clinical benefit and long-term survival in patients with synchronous oligometastatic non-small cell lung cancer: A phase II study

OBJECTIVES

Evidence is rapidly accumulating for the use of radical consolidative treatment (RCT) for patients with oligometastatic non-small cell lung cancer (NSCLC). Nonetheless, published studies have several limitations, including a selection of patients whose favorable characteristics might dictate therapeutic success, as well as scarce prospective data regarding overall survival (OS). The objective of this study was to determine whether RCT increases OS in patients with oligometastatic NSCLC.

MATERIALS AND METHODS

In this prospective, single-arm phase II study, we sought to evaluate the efficacy of RCT in patients with oligometastatic NSCLC in terms of OS. Patients with pathologically confirmed stage IV NSCLC who presented ≤5 synchronous, any-site metastases (including central nervous system [CNS] metastases), as assessed by PET-CT, were included. All patients received four initial cycles of systemic treatment. Following, those with stable disease/partial response received RCT to the primary site and metastases. The response to RCT was evaluated with PET-CT. The primary end-point was OS. Secondary end-points included progression-free survival (PFS) and best response by PET-CT. The study is registered in clinicaltrials.gov (NCT02805530).

RESULTS

Thirty-seven patients were included in the analysis. The mean age was 55.8 years (range: 33-75 years). At diagnosis, 43.2% of patients presented with CNS metastases. Following RCT, 19 (51.4%) patients achieved a complete-response (CR) by PET-CT, while 18 (48.6%) had a non-complete response (NON-CR). The median OS was nonreached (NR) and was positively affected by CR on PET-CT (NR vs. 27.4 [95% CI: 16.4-38.3]; p = 0.011). The median PFS was 23.5 months (95% CI: 13.6-33.3) and was positively affected by CR on PET-CT (NR vs. 14.3 [95% CI: 11.7-16.9]; p < 0.001; HR: 0.19 [0.07-0.52]; p=0.001).

CONCLUSION

Patients with oligometastatic NSCLC who undergo RCT have a high response rate and favorable OS. Patients with a CR by PET-CT have significantly longer OS, rendering this an important potential prognostic marker.

Oridonin enhances the radiosensitivity of lung cancer cells by upregulating Bax and downregulating Bcl-2

Oridonin is an active component of the traditional Chinese herb Rabdosia rubescens. The present study aimed to evaluate the antitumor effects of oridonin on human non-small cell lung cancer (NSCLC) cells and explore whether oridonin could enhance their radiosensitivity. Oridonin was demonstrated to inhibit the proliferation of SPC-A-1 and HCC827 lung cancer cells in a time- and dose-dependent manner, which was detected using the MTT assay. In addition, pretreatment with oridonin for 24 h prior to irradiation was identified to enhance the radiosensitivity of SPC-A-1 cells. Furthermore, the levels of apoptosis regulator BAX (Bax) and apoptosis regulator Bcl-2 (Bcl-2) were detected by western blotting analysis. The results demonstrated that the level of Bax was increased and the level of Bcl-2 was decreased in SPC-A-1 cells treated with oridonin and irradiation compared with the group that received irradiation alone. These results indicate that oridonin may have a novel application as a radiosensitizing agent for the treatment of human NSCLC.

Targeted next generation sequencing identified a high frequency genetic mutated profile in wood smoke exposure-related lung adenocarcinoma patients

BACKGROUND

Wood smoke exposure (WSE) has been associated with an increased risk of lung cancer development. WSE has been related with high frequency of EGFR mutations and low frequency of KRAS mutations. The aim of this study was to evaluate large scale genomic alterations in lung adenocarcinomas associated with WSE using targeted next generation sequencing.

METHODS

DNA multi-targeted sequencing was performed in 42 fresh-frozen samples of advanced lung adenocarcinomas. The TruSeQ Cancer Panel (Illumina) was used for genomic library construction and sequencing assays.

RESULTS

WSE rate was higher in women (p=0.037) and non-smokers (p=0.001). WSE correlated with mutations in the genes SMARCB1 (p=0.002), Ataxia telangiectasia mutated (p=0.004), Kinase Insert Domain Receptor (p=0.006), and were borderline significant in RET and EGFR exon. Genomic alterations significantly co-occurred in the tumor suppressor gene ATM with the following genes: SMARCB1, EGFR exon 7, RET and KDR. Clinical factors associated with poor prognosis were ECOG ≥ 2 (p= 0.014), mutations in KDR (p= 0.004) and APC genes (p < 0.001).

CONCLUSIONS

Lung adenocarcinoma patients with WSE showed a distinctive mutated profile for the SMARCB1, ATM, EGFR exon 7, RET and KDR genes. ECOG status and KDR gene mutations were significantly associated with poor prognosis.

The effect of nabilone on appetite, nutritional status, and quality of life in lung cancer patients: a randomized, double-blind clinical trial

BACKGROUND

Over one half of the patients diagnosed with advanced lung cancer experience anorexia. In addition to its high incidence, cancer-induced anorexia promotes the development of the anorexia-cachexia syndrome, which is related to poor clinical outcomes. Recently, drugs derived from cannabinoids, such as Nabilone, have been recognized for their appetite improvement properties; however, clinical trials to support their use in cancer patients are necessary.

METHODS

This is a randomized, double-blind, placebo-controlled clinical trial to assess the effect of Nabilone vs. placebo on the appetite, nutritional status, and quality of life in patients diagnosed with advanced Non-small cell lung cancer (NSCLC) (NCT02802540).

RESULTS

A total of 65 patients from the outpatient clinic at the National Institute of Cancer (INCan) were assessed for eligibility and 47 were randomized to receive Nabilone (0.5 mg/2 weeks followed by 1.0 mg/6 weeks) or placebo. After 8 weeks of treatment, patients who received Nabilone increased their caloric intake (342-kcal) and had a significantly higher intake of carbohydrates (64 g) compared to patients receiving placebo (p = 0.040). Quality of life also showed significant improvements in patients in the experimental arm of the trial, particularly in role functioning (p = 0.030), emotional functioning (p = 0.018), social functioning (p = 0.036), pain (p = 0.06), and insomnia (p = 0.020). No significant change in these scales was seen in the control group.

CONCLUSION

Nabilone is an adequate and safe therapeutic option to aid in the treatment of patients diagnosed with anorexia. Larger trials are necessary in order to draw robust conclusions in regard to its efficacy in lung cancer patients.