Biomarkers of chronic inflammation and cognitive decline: A prospective observational study

We sought to determine whether the biomarkers of chronic inflammation predict cognitive decline in a prospective observational study. We measured baseline serum soluble urokinase plasminogen activator receptor (suPAR) and high sensitivity C-reactive protein (hs-CRP) levels in 282 participants of the University of Michigan Memory and Aging Project. Cognitive function was measured using the Montreal Cognitive Assessment (MoCA) and the Clinical Dementia Rating (CDR) scale for up to five time points. SuPAR and hs-CRP levels were not significantly higher in participants with mild cognitive impairment (n = 97) or dementia (n = 59), compared to those with normal cognitive function (n = 126). Overall, 14% of participants experienced significant cognitive decline over the study period. The change in MoCA or CDR scores over time did not differ significantly according to baseline suPAR or hs-CRP levels. Chronic systemic inflammation, as measured by serum suPAR or hs-CRP levels, is unlikely to contribute significantly to cognitive decline.

SuPAR, biomarkers of inflammation, and severe outcomes in patients hospitalized for COVID-19: The International Study of Inflammation in COVID-19

Severe coronavirus disease 2019 (COVID-19) is a hyperinflammatory syndrome. The biomarkers of inflammation best suited to triage patients with COVID-19 are unknown. We conducted a prospective multicenter observational study of adult patients hospitalized specifically for COVID-19 from February 1, 2020 to October 19, 2022. Biomarkers measured included soluble urokinase plasminogen activator receptor (suPAR), C-reactive protein, interleukin-6, procalcitonin, ferritin, and D-dimer. In-hospital outcomes examined include death and the need for mechanical ventilation. Patients admitted in the United States (US, n = 1962) were used to compute area under the curves (AUCs) and identify biomarker cutoffs. The combined European cohorts (n = 1137) were used to validate the biomarker cutoffs. In the US cohort, 356 patients met the composite outcome of death (n = 197) or need for mechanical ventilation (n = 290). SuPAR was the most important predictor of the composite outcome and had the highest AUC (0.712) followed by CRP (0.642), ferritin (0.619), IL-6 (0.614), D-dimer (0.606), and lastly procalcitonin (0.596). Inclusion of other biomarkers did not improve discrimination. A suPAR cutoff of 4.0 ng/mL demonstrated a sensitivity of 95.4% (95% CI: 92.4%-98.0%) and negative predictive value (NPV) of 92.5% (95% CI: 87.5%-96.9%) for the composite outcome. Patients with suPAR < 4.0 ng/mL comprised 10.6% of the cohort and had a 0.8% probability of the composite outcome. Applying this cutoff to the validation cohort yielded a sensitivity of 93.8% (90.4%-96.7%) and NPV of 95.5% (93.1%-97.8%) for the composite outcome. Among commonly measured biomarkers, suPAR offered stronger discriminatory ability and may be useful in triaging low-risk patients with COVID-19.

Biomarker Trends, Incidence, and Outcomes of Immune Checkpoint Inhibitor-Induced Myocarditis

Background

Myocarditis is a dreaded and unpredictable complication of immune checkpoint inhibitors (ICI). We sought to determine whether routinely measured biomarkers could be helpful in monitoring for ICI myocarditis.

Objectives

The authors examined biomarker trends of patients on ICI and their association with the incidence of ICI myocarditis and outcomes.

Methods

We conducted an observational cohort study of adults who received at least one dose of ICI at Michigan Medicine between June 2014 and December 2021 and underwent systematic serial testing for aspartate aminotransferase (AST) and alanine aminotransferase (ALT), creatine phosphokinase (CPK), and lactate dehydrogenase during ICI therapy.

Results

Among 2,606 patients (mean age 64 ± 13 years; 60.7% men), 27 (1.0%) were diagnosed with ICI myocarditis. At diagnosis, patients with myocarditis had an elevated high-sensitivity troponin T (100%), ALT (88.9%), AST (85.2%), CPK (88.9%), and lactate dehydrogenase (92.6%). Findings were confirmed in an independent cohort of 30 patients with biopsy-confirmed ICI myocarditis. A total of 95% of patients with ICI myocarditis had elevations in at least 3 biomarkers compared with 5% of patients without myocarditis. Among the noncardiac biomarkers, only CPK was associated (per 100% increase) with the development of myocarditis (HR: 1.83; 95% CI: 1.59-2.10) and all-cause mortality (HR: 1.10; 95% CI: 1.01-1.20) in multivariable analysis. Elevations in CPK had a sensitivity of 99% and specificity of 23% for identifying myocarditis.

Conclusions

ICI myocarditis is associated with changes in AST, ALT, and CPK. An increase in noncardiac biomarkers during ICI treatment, notably CPK, should prompt further evaluation for ICI myocarditis.

Relationship Between Preexisting Cardiovascular Disease and Death and Cardiovascular Outcomes in Critically Ill Patients With COVID-19

BACKGROUND

Preexisting cardiovascular disease (CVD) is perceived as a risk factor for poor outcomes in patients with COVID-19. We sought to determine whether CVD is associated with in-hospital death and cardiovascular events in critically ill patients with COVID-19.

METHODS

This study used data from a multicenter cohort of adults with laboratory-confirmed COVID-19 admitted to intensive care units at 68 centers across the United States from March 1 to July 1, 2020. The primary exposure was CVD, defined as preexisting coronary artery disease, congestive heart failure, or atrial fibrillation/flutter. Myocardial injury on intensive care unit admission defined as a troponin I or T level above the 99th percentile upper reference limit of normal was a secondary exposure. The primary outcome was 28-day in-hospital mortality. Secondary outcomes included cardiovascular events (cardiac arrest, new-onset arrhythmias, new-onset heart failure, myocarditis, pericarditis, or stroke) within 14 days.

RESULTS

Among 5133 patients (3231 male [62.9%]; mean age 61 years [SD, 15]), 1174 (22.9%) had preexisting CVD. A total of 1178 (34.6%) died, and 920 (17.9%) had a cardiovascular event. After adjusting for age, sex, race, body mass index, history of smoking, and comorbidities, preexisting CVD was associated with a 1.15 (95% CI, 0.98-1.34) higher odds of death. No independent association was observed between preexisting CVD and cardiovascular events. Myocardial injury on intensive care unit admission was associated with higher odds of death (adjusted odds ratio, 1.93 [95% CI, 1.61-2.31]) and cardiovascular events (adjusted odds ratio, 1.82 [95% CI, 1.47-2.24]), regardless of the presence of CVD.

CONCLUSIONS

CVD risk factors, rather than CVD itself, were the major contributors to outcomes in critically ill patients with COVID-19. The occurrence of myocardial injury, regardless of CVD, and its association with outcomes suggests it is likely due to multiorgan injury related to acute inflammation rather than exacerbation of preexisting CVD.

REGISTRATION

NCT04343898; https://clinicaltrials.gov/ct2/show/NCT04343898.

Soluble Urokinase Plasminogen Activator Receptor and Venous Thromboembolism in COVID-19

Background Venous thromboembolism (VTE) contributes significantly to COVID-19 morbidity and mortality. The urokinase receptor system is involved in the regulation of coagulation. Levels of soluble urokinase plasminogen activator receptor (suPAR) reflect hyperinflammation and are strongly predictive of outcomes in COVID-19. Whether suPAR levels identify patients with COVID-19 at risk for VTE is unclear. Methods and Results We leveraged a multinational observational study of patients hospitalized for COVID-19 with suPAR and D-dimer levels measured on admission. In 1960 patients (mean age, 58 years; 57% men; 20% Black race), we assessed the association between suPAR and incident VTE (defined as pulmonary embolism or deep vein thrombosis) using logistic regression and Fine-Gray modeling, accounting for the competing risk of death. VTE occurred in 163 (8%) patients and was associated with higher suPAR and D-dimer levels. There was a positive association between suPAR and D-dimer (β=7.34; P=0.002). Adjusted for clinical covariables, including D-dimer, the odds of VTE were 168% higher comparing the third with first suPAR tertiles (adjusted odds ratio, 2.68 [95% CI, 1.51-4.75]; P<0.001). Findings were consistent when stratified by D-dimer levels and in survival analysis accounting for death as a competing risk. On the basis of predicted probabilities from random forest, a decision tree found the combined D-dimer <1 mg/L and suPAR <11 ng/mL cutoffs, identifying 41% of patients with only 3.6% VTE probability. Conclusions Higher suPAR was associated with incident VTE independently of D-dimer in patients hospitalized for COVID-19. Combining suPAR and D-dimer identified patients at low VTE risk. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04818866.

Permissive Cardiotoxicity

The field of cardio-oncology was born from the necessity for recognition and management of cardiovascular diseases among patients with cancer. This need for this specialty continues to grow as patients with cancer live longer as a result of lifesaving targeted and immunologic cancer therapies beyond the usual chemotherapy and/or radiation therapy. Often, potentially cardiotoxic anticancer treatment is necessary in patients with baseline cardiovascular disease. Moreover, patients may need to continue therapy in the setting of incident cancer therapy–associated cardiotoxicity. Herein, we present and discuss the concept of permissive cardiotoxicity as a novel term that represents an essential concept in the field of cardio-oncology and among practicing cardio-oncology specialists. It emphasizes a proactive rather than reactive approach to continuation of lifesaving cancer therapies in order to achieve the best oncologic outcome while mitigating associated and potentially off-target cardiotoxicities.

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Permissive cardiotoxicity is a terminology that represents a vital concept in cardio-oncology

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It emphasizes continued cancer therapy if appropriate, while mitigating cardiotoxicities.

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Its application is guided by understanding the cancer treatment, alternatives, and prognosis.

Differences in Inflammation, Treatment, and Outcomes Between Black and Non-Black Patients Hospitalized for COVID-19: A Prospective Cohort Study

PURPOSE

Racial disparities in coronavirus disease 2019 (COVID-19) outcomes have been described. We sought to determine whether differences in inflammatory markers, use of COVID-19 therapies, enrollment in clinical trials, and in-hospital outcomes contribute to racial disparities between Black and non-Black patients hospitalized for COVID-19.

METHODS

We leveraged a prospective cohort study that enrolled 1325 consecutive patients hospitalized for COVID-19, of whom 341 (25.7%) were Black. We measured biomarkers of inflammation and collected data on the use COVID-19-directed therapies, enrollment in COVID-19 clinical trials, mortality, need for renal replacement therapy, and need for mechanical ventilation.

RESULTS

Compared to non-Black patients, Black patients had a higher prevalence of COVID-19 risk factors including obesity, hypertension, and diabetes mellitus and were more likely to require renal replacement therapy (15.8% vs 7.1%, P < .001) and mechanical ventilation (37.2% vs 26.6%, P < .001) during their hospitalization. Mortality was similar between both groups (15.5% for Blacks vs 14.0% for non-Blacks, P = .49). Black patients were less likely to receive corticosteroids (44.9% vs 63.8%, P< .001) or remdesivir (23.8% vs 57.8%, P < .001) and were less likely to be enrolled in COVID-19 clinical trials (15.3% vs 28.2%, P < .001). In adjusted analyses, Black race was associated with lower levels of C-reactive protein and soluble urokinase receptor and higher odds of death, mechanical ventilation, and renal replacement therapy. Differences in outcomes were not significant after adjusting for use of remdesivir and corticosteroids.

CONCLUSIONS

Racial differences in outcomes of patients with COVID-19 may be related to differences in inflammatory response and differential use of therapies.

Inflammation, Hyperglycemia, and Adverse Outcomes in Individuals With Diabetes Mellitus Hospitalized for COVID-19

OBJECTIVE

Diabetes mellitus (DM) is a major risk factor for severe coronavirus disease 2019 (COVID-19) for reasons that are unclear.

RESEARCH DESIGN AND METHODS

We leveraged the International Study of Inflammation in COVID-19 (ISIC), a multicenter observational study of 2,044 patients hospitalized with COVID-19, to characterize the impact of DM on in-hospital outcomes and assess the contribution of inflammation and hyperglycemia to the risk attributed to DM. We measured biomarkers of inflammation collected at hospital admission and collected glucose levels and insulin data throughout hospitalization. The primary outcome was the composite of in-hospital death, need for mechanical ventilation, and need for renal replacement therapy.

RESULTS

Among participants (mean age 60 years, 58.2% males), those with DM (n = 686, 33.5%) had a significantly higher cumulative incidence of the primary outcome (37.8% vs. 28.6%) and higher levels of inflammatory biomarkers than those without DM. Among biomarkers, DM was only associated with higher soluble urokinase plasminogen activator receptor (suPAR) levels in multivariable analysis. Adjusting for suPAR levels abrogated the association between DM and the primary outcome (adjusted odds ratio 1.23 [95% CI 0.78, 1.37]). In mediation analysis, we estimated the proportion of the effect of DM on the primary outcome mediated by suPAR at 84.2%. Hyperglycemia and higher insulin doses were independent predictors of the primary outcome, with effect sizes unaffected by adjusting for suPAR levels.

CONCLUSIONS

Our findings suggest that the association between DM and outcomes in COVID-19 is largely mediated by hyperinflammation as assessed by suPAR levels, while the impact of hyperglycemia is independent of inflammation.

Angiotensin-Converting Enzyme Inhibitors, Angiotensin II Receptor Blockers, and Outcomes in Patients Hospitalized for COVID-19

Background

Use of angiotensin‐converting enzyme inhibitors and angiotensin receptor blockers (ACEi/ARB) is thought to affect COVID‐19 through modulating levels of angiotensin‐converting enzyme 2, the cell entry receptor for SARS‐CoV2. We sought to assess the association between ACEi/ARB, biomarkers of inflammation, and outcomes in patients hospitalized for COVID‐19.

Methods and Results

We leveraged the ISIC (International Study of Inflammation in COVID‐19), identified patients admitted for symptomatic COVID‐19 between February 1, 2020 and June 1, 2021 for COVID‐19, and examined the association between in‐hospital ACEi/ARB use and all‐cause death, need for ventilation, and need for dialysis. We estimated the causal effect of ACEi/ARB on the composite outcomes using marginal structural models accounting for serial blood pressure and serum creatinine measures. Of 2044 patients in ISIC, 1686 patients met inclusion criteria, of whom 398 (23.6%) patients who were previously on ACEi/ARB received at least 1 dose during their hospitalization for COVID‐19. There were 215 deaths, 407 patients requiring mechanical ventilation, and 124 patients who required dialysis during their hospitalization. Prior ACEi/ARB use was associated with lower levels of soluble urokinase plasminogen activator receptor and C‐reactive protein. In multivariable analysis, in‐hospital ACEi/ARB use was associated with a lower risk of the composite outcome of in‐hospital death, mechanical ventilation, or dialysis (adjusted hazard ratio 0.49, 95% CI [0.36–0.65]).

Conclusions

In patients hospitalized for COVID‐19, ACEi/ARB use was associated with lower levels of inflammation and lower risk of in‐hospital outcomes. Clinical trials will define the role of ACEi/ARB in the treatment of COVID‐19.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04818866.

Representation of Black patients in heart failure clinical trials

PURPOSE OF REVIEW

Black patients with heart failure in the United States are underrepresented in clinical trials relative to their overrepresentation in the heart failure population and in adverse heart failure outcomes. We aim to evaluate historical trends in this space and highlight recent developments.

RECENT FINDINGS

Multiple landmark heart failure trials published since 2019 have underrepresented Black patients, though several discussed this lack of representation as limitations. A review of large heart failure clinical trials from 2001 to 2016 found persistent underrepresentation of Black patients without significant change over time. Trials enrolling from North America exclusively had more proportional representation, enrolling an average of 31.6% Black participants.

SUMMARY

There is a shrinking proportion of Black patients in pivotal heart failure trials despite a higher prevalence of disease and associated adverse outcomes. There is increasing awareness of these disparities within the heart failure community, potentially leading to improved representation in future studies.

In-hospital cardiac arrest in critically ill patients with covid-19: multicenter cohort study

OBJECTIVES

To estimate the incidence, risk factors, and outcomes associated with in-hospital cardiac arrest and cardiopulmonary resuscitation in critically ill adults with coronavirus disease 2019 (covid-19).

DESIGN

Multicenter cohort study.

SETTING

Intensive care units at 68 geographically diverse hospitals across the United States.

PARTICIPANTS

Critically ill adults (age ≥18 years) with laboratory confirmed covid-19.

MAIN OUTCOME MEASURES

In-hospital cardiac arrest within 14 days of admission to an intensive care unit and in-hospital mortality.

RESULTS

Among 5019 critically ill patients with covid-19, 14.0% (701/5019) had in-hospital cardiac arrest, 57.1% (400/701) of whom received cardiopulmonary resuscitation. Patients who had in-hospital cardiac arrest were older (mean age 63 (standard deviation 14) v 60 (15) years), had more comorbidities, and were more likely to be admitted to a hospital with a smaller number of intensive care unit beds compared with those who did not have in-hospital cardiac arrest. Patients who received cardiopulmonary resuscitation were younger than those who did not (mean age 61 (standard deviation 14) v 67 (14) years). The most common rhythms at the time of cardiopulmonary resuscitation were pulseless electrical activity (49.8%, 199/400) and asystole (23.8%, 95/400). 48 of the 400 patients (12.0%) who received cardiopulmonary resuscitation survived to hospital discharge, and only 7.0% (28/400) survived to hospital discharge with normal or mildly impaired neurological status. Survival to hospital discharge differed by age, with 21.2% (11/52) of patients younger than 45 years surviving compared with 2.9% (1/34) of those aged 80 or older.

CONCLUSIONS

Cardiac arrest is common in critically ill patients with covid-19 and is associated with poor survival, particularly among older patients.

Soluble Urokinase Receptor (SuPAR) in COVID-19-Related AKI

BACKGROUND

AKI commonly occurs in patients with coronavirus disease 2019 (COVID-19). Its pathogenesis is poorly understood. The urokinase receptor system is a key regulator of the intersection between inflammation, immunity, and coagulation, and soluble urokinase plasminogen activator receptor (suPAR) has been identified as an immunologic risk factor for AKI. Whether suPAR is associated with COVID-19-related AKI is unknown.

METHODS

In a multinational observational study of adult patients hospitalized for COVID-19, we measured suPAR levels in plasma samples from 352 adult patients that had been collected within 48 hours of admission. We examined the association between suPAR levels and incident in-hospital AKI.

RESULTS

Of the 352 patients (57.4% were male, 13.9% were black, and mean age was 61 years), 91 (25.9%) developed AKI during their hospitalization, of whom 25 (27.4%) required dialysis. The median suPAR level was 5.61 ng/ml. AKI incidence rose with increasing suPAR tertiles, from a 6.0% incidence in patients with suPAR <4.60 ng/ml (first tertile) to a 45.8% incidence of AKI in patients with suPAR levels >6.86 ng/ml (third tertile). None of the patients with suPAR <4.60 ng/ml required dialysis during their hospitalization. In multivariable analysis, the highest suPAR tertile was associated with a 9.15-fold increase in the odds of AKI (95% confidence interval [95% CI], 3.64 to 22.93) and a 22.86-fold increase in the odds of requiring dialysis (95% CI, 2.77 to 188.75). The association was independent of inflammatory markers and persisted across subgroups.

CONCLUSIONS

Admission suPAR levels in patients hospitalized for COVID-19 are predictive of in-hospital AKI and the need for dialysis. SuPAR may be a key component of the pathophysiology of AKI in COVID-19.

ADAM10 and ADAM17 cleave PD-L1 to mediate PD-(L)1 inhibitor resistance

ADAM10 and ADAM17 expression and soluble PD-L1 (sPD-L1) predict poor prognosis in many malignancies, including in patients treated with PD-(L)1 inhibitors. The mechanism of soluble PD-L1 production and its effects are unknown. Here we uncover a novel mechanism of ADAM10- and ADAM17-mediated resistance to PD-(L)1 inhibitors. ADAM10 and ADAM17 cleave PD-L1 from the surface of malignant cells and extracellular vesicles. This cleavage produces an active sPD-L1 fragment that induces apoptosis in CD8 + T cells and compromises the killing of tumor cells by CD8 + T cells. Reduced tumor site PD-L1 protein-to-mRNA ratios predict poor outcomes and are correlated with elevated ADAM10 and ADAM17 expression in multiple cancers. These results may explain the discordance between PD-L1 immunohistochemistry and PD-(L)1 inhibitor response. Thus, including ADAM10 and ADAM17 tissue staining may improve therapy selection. Furthermore, treatment with an ADAM10/ADAM17 inhibitor may abrogate PD-(L)1 inhibitor resistance and improve clinical responses to PD-(L)1 immunotherapy.

Abstract A210: Tumor-associated ADAM10 and ADAM17 produce soluble PD-L1 (sPD-L1, sB7-H1) and affect downstream tumor immunity – A resistance mechanism to PD-1 checkpoint blockade in melanoma

Background: Tumor surface PD-L1 (B7-H1) signals through T-cell surface receptor PD-1 to suppress antitumor immunity. PD-1 inhibitors like pembrolizumab block this pathway to prevent tumor escape from immunosurveillance. These PD-1 checkpoint inhibitors achieve objective response in 20-30% of patients with melanoma (1-3). As the majority of these patients are resistant to this treatment, there is a critical need to combat PD-1 checkpoint inhibitor resistance in melanoma. What is the mechanism of PD-1 checkpoint inhibitor resistance in melanoma? Our group has reported that soluble PD-L1 (sPD-L1, sB7-H1) is elevated in the serum of patients with PD-1 inhibitor-resistant melanoma and non-small cell lung cancer (NSCLC) (4). We have also shown that soluble PD-L1 is produced by cleavage from other tumor types and leads to apoptosis in CD8+ T-cells (5). The aim of this study is to confirm the source of sPD-L1 in human melanoma and its relation to outcomes. Methods: B7H1-expressing transgenic melanoma cells (Mel-B7H1) were treated with an array of protease inhibitors over 24 hours. Cells were then pelleted and supernatants were analyzed by ELISA for sPD-L1 (sB7-H1) production. Tumor serum samples were also analyzed by ELISA for sPD-L1 production.Tumor pathology slides from patients with melanoma (serum donors from the above study) were stained by immunohistochemistry with antibodies against proteases ADAM10 or ADAM17. Slides were visualized by microscopy for the presence of these antigens. Activated human CD8+ T-cells were cultured with recombinant human B7-H1 (PD-L1) protein, sPD-L1-rich, or sPD-L1-depleted supernatants from a tumor cell line in the presence of placebo or PD-1 checkpoint inhibitor antibodies. Cell survival was measured at 48 hours by flow cytometry.Results: ADAM10 inhibitor GI254023X, ADAM17 inhibitor TAPI-0, and broad metalloprotease inhibitor TAPI-2 inhibited Mel-B7H1 production of sB7H1 (p&lt;0.001, 0.095, and 0.001 respectively). Specific inhibitors of other metalloproteases did not significantly alter sB7H1 production. PD-L1 transcription levels were not significantly altered. Tumor pathology slides from patients with high serum sPD-L1 exhibited high ADAM10 and/or ADAM17 staining. Conversely, tumors from patients with low-sPD-L1levels tended to exhibit low ADAM10 and/or ADAM17 staining. Recombinant PD-L1 and PD-L1-rich supernatants induced cell death of CD8+ T-cells, whereas PBS control solution and PD-L1-depleted supernatants did not. Supraphysiologic doses of pembrolizumab decreased cell death in PD-L1-rich supernatant-treated CD8+ T-cells. Conclusions: Matrix metalloprotease inhibitors ADAM10 and ADAM17 mediate sPD-L1 production from melanoma cells. In samples from patients with melanoma, immunohistochemical staining of these proteases in tumor tissue correlates with serum sPD-L1 levels. As we have shown previously, sPD-L1 induces apoptosis of activated CD8+ T-cells, which may explain PD-1 inhibitor resistance in most patients with melanoma.We posit that sPD-L1 outcompetes PD-1 inhibitors to suppress tumor immunosurveillance. Our results suggest that the combination of ADAM10/17 inhibitor and PD-1 checkpoint inhibitor may overcome this mechanism of PD-1 resistance in melanoma and other cancers. Future studies will determine (A) how a combined ADAM10/17 inhibitor and PD-1 inhibitor may function in clinical use, (B) how tumor-derived sPD-L1 signals downstream to cause apoptosis in T-cells, and (C) whether surface ADAM10/17 predict surface PD-L1 staining in melanoma. References: 1. Ribas et al., Lancet Oncol 2015;16(8):908–18. 2. Hamid et al., Ann Oncol 2016;27:6. 3. Weber et al., Lancet Oncol 2015:16(4):375–84. 4. Dronca et al., J Clin Oncol 2017:35(15):11534. 5. Orme et al., AACR Adv Malig Lymphoma 2018.

Citation Format: Jacob J. Orme, Khalid Jazieh, Susan Harrington, Matthew Ball, Tariq U. Azam, Xin (Cindy) Liu, Tiancheng Xie, Aaron Mansfield, Roxana S. Dronca, Haidong Dong. Tumor-associated ADAM10 and ADAM17 produce soluble PD-L1 (sPD-L1, sB7-H1) and affect downstream tumor immunity – A resistance mechanism to PD-1 checkpoint blockade in melanoma [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A210.

Characterization of Comorbidities Limiting the Recruitment of Patients in Early Phase Clinical Trials

BACKGROUND

Early phase clinical trials evaluate the safety and efficacy of new treatments. The exclusion/inclusion criteria in these trials are usually rigorous and may exclude many patients seen in clinical practice. Our objective was to study the comorbidities limiting the participation of patients with breast, colorectal, or lung cancer in clinical trials.

MATERIALS AND METHODS

We queried ClinicalTrials.gov on December 31, 2016. We reviewed the eligibility criteria of 1,103 trials. Logistic regression analyses were completed, and exclusion was studied as a binary variable.

RESULTS

Out of 1,103 trials, 70 trials (6%) excluded patients >75 years of age, and 45% made no reference to age. Eighty-six percent of trials placed restrictions on patients with history of prior malignancies. Regarding central nervous system (CNS) metastasis, 416 trials (38%) excluded all patients with CNS metastasis, and 373 (34%) only allowed asymptomatic CNS metastasis. Regarding chronic viral infections, 347 trials (31%) excluded all patients with human immunodeficiency virus, and 228 trials (21%) excluded all patients with hepatitis B or C infection. On univariate analysis, chemotherapy trials were more likely to exclude patients with CNS metastasis and history of other malignancies than targeted therapy trials. Multivariate analysis demonstrated that industry-sponsored trials had higher odds of excluding patients with compromised liver function.

CONCLUSION

Many clinical trials excluded large segments of the population of patients with cancer. Frequent exclusion criteria included patients with CNS metastasis, history of prior malignancies, and chronic viral infections. The criteria for participation in some clinical trials may be overly restrictive and limit enrollment.

IMPLICATIONS FOR PRACTICE

The results of this study revealed that most early phase clinic trials contain strict exclusion criteria, potentially excluding the patients who may be more likely to represent the population treated in clinical settings, leaving patients susceptible to unintended harm from inappropriate generalization of trial results. Careful liberalization of the inclusion/exclusion criteria in clinical trials will allow investigators to understand the benefits and drawbacks of the experimental drug for a broader population, and possibly improve recruitment of patients with cancer into clinical trials.