Sergey Sikora

Intravenously Delivered Mesenchymal Stem Cells

Rationale: Virtually all mesenchymal stem cell (MSC) studies assume that therapeutic effects accrue from local myocardial effects of engrafted MSCs. Because few intravenously administered MSCs engraft in the myocardium, studies have mainly utilized direct myocardial delivery. We adopted a different paradigm. Objective: To test whether intravenously administered MSCs reduce left ventricular (LV) dysfunction both post–acute myocardial infarction and in ischemic cardiomyopathy and that these effects are caused, at least partly, by systemic anti-inflammatory activities. Methods and Results: Mice underwent 45 minutes of left anterior descending artery occlusion. Human MSCs, grown chronically at 5% O2, were administered intravenously. LV function was assessed by serial echocardiography, 2,3,5-triphenyltetrazolium chloride staining determined infarct size, and fluorescence-activated cell sorting assessed cell composition. Fluorescent and radiolabeled MSCs (1×106) were injected 24 hours post–myocardial infarction and homed to regions of myocardial injury; however, the myocardium contained only a small proportion of total MSCs. Mice received 2×106 MSCs or saline intravenously 24 hours post–myocardial infarction (n=16 per group). At day 21, we harvested blood and spleens for fluorescence-activated cell sorting and hearts for 2,3,5-triphenyltetrazolium chloride staining. Adverse LV remodeling and deteriorating LV ejection fraction occurred in control mice with large infarcts (≥25% LV). Intravenous MSCs eliminated the progressive deterioration in LV end-diastolic volume and LV end-systolic volume. MSCs significantly decreased natural killer cells in the heart and spleen and neutrophils in the heart. Specific natural killer cell depletion 24 hours pre–acute myocardial infarction significantly improved infarct size, LV ejection fraction, and adverse LV remodeling, changes associated with decreased neutrophils in the heart. In an ischemic cardiomyopathy model, mice 4 weeks post–myocardial infarction were randomized to tail-vein injection of 2×106 MSCs, with injection repeated at week 3 (n=16) versus PBS control (n=16). MSCs significantly increased LV ejection fraction and decreased LV end-systolic volume. Conclusions: Intravenously administered MSCs for acute myocardial infarction attenuate the progressive deterioration in LV function and adverse remodeling in mice with large infarcts, and in ischemic cardiomyopathy, they improve LV function, effects apparently modulated in part by systemic anti-inflammatory activities.

Developing New Treatments for Heart Failure: Focus on the Heart

Compared with heart failure (HF) care 20 to 30 years ago, there has been tremendous advancement in therapy for ambulatory HF with reduced ejection fraction with the use of agents that block maladaptive neurohormonal pathways. However, during the past decade, with few notable exceptions, the frequency of successful drug development programs has fallen as most novel therapies have failed to offer incremental benefit or raised safety concerns (ie, hypotension). Moreover, no therapy has been approved specifically for HF with preserved ejection fraction or for worsening chronic HF (including acutely decompensated HF). Across the spectrum of HF, preliminary results from many phase II trials have been promising but are frequently followed by unsuccessful phase III studies, highlighting a disconnect in the translational process between basic science discovery, early drug development, and definitive clinical testing in pivotal trials. A major unmet need in HF drug development is the ability to identify homogeneous subsets of patients whose underlying disease is driven by a specific mechanism that can be targeted using a new therapeutic agent. Drug development strategies should increasingly consider therapies that facilitate reverse remodeling by directly targeting the heart itself rather than strictly focusing on agents that unload the heart or target systemic neurohormones. Advancements in cardiac imaging may allow for more focused and direct assessment of drug effects on the heart early in the drug development process. To better understand and address the array of challenges facing current HF drug development, so that future efforts may have a better chance for success, the Food and Drug Administration facilitated a meeting on February 17, 2015, which was attended by clinicians, researchers, regulators, and industry representatives. The following discussion summarizes the key takeaway dialogue from this meeting.

Intravenous Allogeneic Mesenchymal Stem Cells for Nonischemic CardiomyopathyNovelty and Significance: Safety and Efficacy Results of a Phase II-A Randomized Trial

Rationale: Potential benefits of mesenchymal stem cell (MSC) therapy in heart failure may be related to paracrine properties and systemic effects, including anti-inflammatory activities. If this hypothesis is valid, intravenous administration of MSCs should improve outcomes in heart failure, an entity in which excessive chronic inflammation may play a pivotal role. Objective: To assess the safety and preliminary efficacy of intravenously administered ischemia-tolerant MSCs (itMSCs) in patients with nonischemic cardiomyopathy. Methods and Results: This was a single-blind, placebo-controlled, crossover, randomized phase II-a trial of nonischemic cardiomyopathy patients with left ventricular ejection fraction ≤40% and absent hyperenhancement on cardiac magnetic resonance imaging. Patients were randomized to intravenously administered itMSCs (1.5×106 cells/kg) or placebo; at 90 days, each group received the alternative treatment. Overall, 22 patients were randomized to itMSC (n=10) and placebo (n=12) at baseline. After crossover, data were available for 22 itMSC patients. No major differences in death, hospitalization, or serious adverse events were noted between the 2 treatments. Change from baseline in left ventricular ejection fraction and ventricular volumes was not significantly different between therapies. Compared with placebo, itMSC therapy increased 6-minute walk distance (+36.47 m, 95% confidence interval 5.98–66.97; P =0.02) and improved Kansas City Cardiomyopathy clinical summary (+5.22, 95% confidence interval 0.70–9.74; P =0.02) and functional status scores (+5.65, 95% confidence interval −0.11 to 11.41; P =0.06). The data demonstrated MSC-induced immunomodulatory effects, the magnitude of which correlated with improvement in left ventricular ejection fraction. Conclusions: In this pilot study of patients with nonischemic cardiomyopathy, itMSC therapy was safe, caused immunomodulatory effects, and was associated with improvements in health status and functional capacity. Clinical Trial Registration: URL: . Unique identifier: [NCT02467387][1]. # Novelty and Significance {#article-title-23} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT02467387&atom=%2Fcircresaha%2F120%2F2%2F332.atomRationale: Potential benefits of mesenchymal stem cell (MSC) therapy in heart failure may be related to paracrine properties and systemic effects, including anti-inflammatory activities. If this hypothesis is valid, intravenous administration of MSCs should improve outcomes in heart failure, an entity in which excessive chronic inflammation may play a pivotal role. Objective: To assess the safety and preliminary efficacy of intravenously administered ischemia-tolerant MSCs (itMSCs) in patients with nonischemic cardiomyopathy. Methods and Results: This was a single-blind, placebo-controlled, crossover, randomized phase II-a trial of nonischemic cardiomyopathy patients with left ventricular ejection fraction ⩽40% and absent hyperenhancement on cardiac magnetic resonance imaging. Patients were randomized to intravenously administered itMSCs (1.5×106 cells/kg) or placebo; at 90 days, each group received the alternative treatment. Overall, 22 patients were randomized to itMSC (n=10) and placebo (n=12) at baseline. After crossover, data were available for 22 itMSC patients. No major differences in death, hospitalization, or serious adverse events were noted between the 2 treatments. Change from baseline in left ventricular ejection fraction and ventricular volumes was not significantly different between therapies. Compared with placebo, itMSC therapy increased 6-minute walk distance (+36.47 m, 95% confidence interval 5.98–66.97; P=0.02) and improved Kansas City Cardiomyopathy clinical summary (+5.22, 95% confidence interval 0.70–9.74; P=0.02) and functional status scores (+5.65, 95% confidence interval −0.11 to 11.41; P=0.06). The data demonstrated MSC-induced immunomodulatory effects, the magnitude of which correlated with improvement in left ventricular ejection fraction. Conclusions: In this pilot study of patients with nonischemic cardiomyopathy, itMSC therapy was safe, caused immunomodulatory effects, and was associated with improvements in health status and functional capacity. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02467387.

Pathway-Specific Aggregate Biomarker Risk Score Is Associated With Burden of Coronary Artery Disease and Predicts Near-Term Risk of Myocardial Infarction and Death

Background— Inflammation, coagulation, and cell stress contribute to atherosclerosis and its adverse events. A biomarker risk score (BRS) based on the circulating levels of biomarkers C-reactive protein, fibrin degradation products, and heat shock protein-70 representing these 3 pathways was a strong predictor of future outcomes. We investigated whether soluble urokinase plasminogen activator receptor (suPAR), a marker of immune activation, is predictive of outcomes independent of the aforementioned markers and whether its addition to a 3-BRS improves risk reclassification. Methods and Results— C-reactive protein, fibrin degradation product, heat shock protein-70, and suPAR were measured in 3278 patients undergoing coronary angiography. The BRS was calculated by counting the number of biomarkers above a cutoff determined using the Youden’s index. Survival analyses were performed using models adjusted for traditional risk factors. A high suPAR level ≥3.5 ng/mL was associated with all-cause death and myocardial infarction (hazard ratio, 1.83; 95% confidence interval, 1.43–2.35) after adjustment for risk factors, C-reactive protein, fibrin degradation product, and heat shock protein-70. Addition of suPAR to the 3-BRS significantly improved the C statistic, integrated discrimination improvement, and net reclassification index for the primary outcome. A BRS of 1, 2, 3, or 4 was associated with a 1.81-, 2.59-, 6.17-, and 8.80-fold increase, respectively, in the risk of death and myocardial infarction. The 4-BRS was also associated with severity of coronary artery disease and composite end points. Conclusions— SuPAR is independently predictive of adverse outcomes, and its addition to a 3-BRS comprising C-reactive protein, fibrin degradation product, and heat shock protein-70 improved risk reclassification. The clinical utility of using a 4-BRS for risk prediction and management of patients with coronary artery disease warrants further study.

Rationale and design of a randomized controlled trial of allogeneic mesenchymal stem cells in patients with nonischemic cardiomyopathy.

Aims This article describes an ongoing study investigating the safety and efficacy of ischemia-tolerant mesenchymal stem cell (MSC) therapy in patients with nonischemic heart failure and dysfunctional viable myocardium without scarring. This study will follow principles of the previously described mechanistic translational-phase concept whereby the effect of the study agent on laboratory and imaging markers of cardiac structure and function will be tested in a small homogenous cohort with the goal to enhance the understanding of the effect of interventions on cardiac remodeling and performance. Study design This single-blind, placebo-controlled, crossover, multicenter, randomized study will assess the safety, tolerability, and preliminary efficacy of a single intravenous (i.v.) dose of allogeneic ischemia-tolerant MSCs in individuals with heart failure of nonischemic cause, ejection fraction 40% or less, and dysfunctional viable myocardium who have been receiving guideline-directed medical therapy. Eligible patients will have no evidence of baseline replacement scarring on delayed-enhancement cardiac magnetic resonance (CMR). Approximately 20 patients will be randomized in a 1 : 1 ratio to receive an i.v. infusion of ischemia-tolerant MSCs or placebo. At 90 days, the two groups will undergo crossover and received the alternative treatment. The primary endpoint is safety, as evaluated through at least 1-year post-MSC infusion. Additional efficacy endpoints will include measures of cardiac structure and function, as evaluated by serial cine-CMR and transthoracic echocardiography at 90 and 180 days post-initial infusion. Conclusion This pilot study will explore the safety and effects on cardiac structure and function of i.v. injection of ischemia-tolerant MSCs in a small homogenous cohort of nonischemic heart failure patients with reduced ejection fraction and absent replacement scarring on CMR. This study also represents a prospective mechanistic translational-phase study using baseline and serial CMR imaging in heart failure patients and serves as a potential model for design of future heart failure trials (ClinicalTrials.gov identifier: NCT02467387).

Intravenous Allogeneic Mesenchymal Stem Cells for Non-Ischemic Cardiomyopathy: Safety and Efficacy Results of a Phase II-A Randomized Trial.

Rationale: Potential benefits of mesenchymal stem cell (MSC) therapy in heart failure may be related to paracrine properties and systemic effects, including anti-inflammatory activities. If this hypothesis is valid, intravenous administration of MSCs should improve outcomes in heart failure, an entity in which excessive chronic inflammation may play a pivotal role. Objective: To assess the safety and preliminary efficacy of intravenously administered ischemia-tolerant MSCs (itMSCs) in patients with nonischemic cardiomyopathy. Methods and Results: This was a single-blind, placebo-controlled, crossover, randomized phase II-a trial of nonischemic cardiomyopathy patients with left ventricular ejection fraction ≤40% and absent hyperenhancement on cardiac magnetic resonance imaging. Patients were randomized to intravenously administered itMSCs (1.5×106 cells/kg) or placebo; at 90 days, each group received the alternative treatment. Overall, 22 patients were randomized to itMSC (n=10) and placebo (n=12) at baseline. After crossover, data were available for 22 itMSC patients. No major differences in death, hospitalization, or serious adverse events were noted between the 2 treatments. Change from baseline in left ventricular ejection fraction and ventricular volumes was not significantly different between therapies. Compared with placebo, itMSC therapy increased 6-minute walk distance (+36.47 m, 95% confidence interval 5.98–66.97; P =0.02) and improved Kansas City Cardiomyopathy clinical summary (+5.22, 95% confidence interval 0.70–9.74; P =0.02) and functional status scores (+5.65, 95% confidence interval −0.11 to 11.41; P =0.06). The data demonstrated MSC-induced immunomodulatory effects, the magnitude of which correlated with improvement in left ventricular ejection fraction. Conclusions: In this pilot study of patients with nonischemic cardiomyopathy, itMSC therapy was safe, caused immunomodulatory effects, and was associated with improvements in health status and functional capacity. Clinical Trial Registration: URL: . Unique identifier: [NCT02467387][1]. # Novelty and Significance {#article-title-23} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT02467387&atom=%2Fcircresaha%2F120%2F2%2F332.atomRationale: Potential benefits of mesenchymal stem cell (MSC) therapy in heart failure may be related to paracrine properties and systemic effects, including anti-inflammatory activities. If this hypothesis is valid, intravenous administration of MSCs should improve outcomes in heart failure, an entity in which excessive chronic inflammation may play a pivotal role. Objective: To assess the safety and preliminary efficacy of intravenously administered ischemia-tolerant MSCs (itMSCs) in patients with nonischemic cardiomyopathy. Methods and Results: This was a single-blind, placebo-controlled, crossover, randomized phase II-a trial of nonischemic cardiomyopathy patients with left ventricular ejection fraction ⩽40% and absent hyperenhancement on cardiac magnetic resonance imaging. Patients were randomized to intravenously administered itMSCs (1.5×106 cells/kg) or placebo; at 90 days, each group received the alternative treatment. Overall, 22 patients were randomized to itMSC (n=10) and placebo (n=12) at baseline. After crossover, data were available for 22 itMSC patients. No major differences in death, hospitalization, or serious adverse events were noted between the 2 treatments. Change from baseline in left ventricular ejection fraction and ventricular volumes was not significantly different between therapies. Compared with placebo, itMSC therapy increased 6-minute walk distance (+36.47 m, 95% confidence interval 5.98–66.97; P=0.02) and improved Kansas City Cardiomyopathy clinical summary (+5.22, 95% confidence interval 0.70–9.74; P=0.02) and functional status scores (+5.65, 95% confidence interval −0.11 to 11.41; P=0.06). The data demonstrated MSC-induced immunomodulatory effects, the magnitude of which correlated with improvement in left ventricular ejection fraction. Conclusions: In this pilot study of patients with nonischemic cardiomyopathy, itMSC therapy was safe, caused immunomodulatory effects, and was associated with improvements in health status and functional capacity. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02467387.

An Aggregate Biomarker Risk Score Predicts High Risk of Near‐Term Myocardial Infarction and Death: Findings From BARI 2D (Bypass Angioplasty Revascularization Investigation 2 Diabetes)

Background In a previous study, we found that a biomarker risk score (BRS) comprised of C‐reactive protein, fibrin‐degradation products, and heat shock protein‐70 predicts risk of myocardial infarction and death in coronary artery disease patients. We sought to: (1) validate the BRS in the independent BARI 2D (Bypass Angioplasty Revascularization Investigation 2 Diabetes) cohort, (2) investigate whether 1 year of intensive medical therapy is associated with improved BRS, and (3) elucidate whether an altered BRS parallels altered risk. Methods and Results Two thousand thirty‐two subjects with coronary artery disease were followed for 5.3±1.1 years for cardiovascular events. Biomarkers were measured at baseline and retested in 1304 subjects at 1 year. BRS was determined as the biomarker number above previously defined cut‐off values (C‐reactive protein >3 mg/L, heat shock protein‐70 >0.313 ng/mL, and fibrin‐degradation products >1 μg/mL). After adjustment for covariates, those with a BRS of 3 had a 4‐fold increased risk of all‐cause death and a 6.8‐fold increased risk of cardiac death compared with those with a BRS of 0 (95% CI, 2.9–16.0; P<0.0001). All individual biomarkers decreased by 1 year, with ≈80% of patients decreasing their BRS. BRS recalibrated at 1 year also predicted risk. Those with 1‐year BRS of 2 to 3 had a 4‐year mortality rate of 21.1% versus 7.4% for those with BRS of 0 to 1 (P<0.0001). Conclusions Our results validate the ability of the BRS to identify coronary artery disease patients at very high near‐term risk of myocardial infarction/death. After 1 year of intensive medical therapy, the BRS decreased significantly, and the reclassified BRS continued to track with risk. Our results suggest that repeated BRS measurements might be used to assess risk and recalibrate therapy.

Intravenous Allogeneic Mesenchymal Stem Cells for Nonischemic CardiomyopathyNovelty and Significance

Rationale: Potential benefits of mesenchymal stem cell (MSC) therapy in heart failure may be related to paracrine properties and systemic effects, including anti-inflammatory activities. If this hypothesis is valid, intravenous administration of MSCs should improve outcomes in heart failure, an entity in which excessive chronic inflammation may play a pivotal role. Objective: To assess the safety and preliminary efficacy of intravenously administered ischemia-tolerant MSCs (itMSCs) in patients with nonischemic cardiomyopathy. Methods and Results: This was a single-blind, placebo-controlled, crossover, randomized phase II-a trial of nonischemic cardiomyopathy patients with left ventricular ejection fraction ≤40% and absent hyperenhancement on cardiac magnetic resonance imaging. Patients were randomized to intravenously administered itMSCs (1.5×106 cells/kg) or placebo; at 90 days, each group received the alternative treatment. Overall, 22 patients were randomized to itMSC (n=10) and placebo (n=12) at baseline. After crossover, data were available for 22 itMSC patients. No major differences in death, hospitalization, or serious adverse events were noted between the 2 treatments. Change from baseline in left ventricular ejection fraction and ventricular volumes was not significantly different between therapies. Compared with placebo, itMSC therapy increased 6-minute walk distance (+36.47 m, 95% confidence interval 5.98–66.97; P =0.02) and improved Kansas City Cardiomyopathy clinical summary (+5.22, 95% confidence interval 0.70–9.74; P =0.02) and functional status scores (+5.65, 95% confidence interval −0.11 to 11.41; P =0.06). The data demonstrated MSC-induced immunomodulatory effects, the magnitude of which correlated with improvement in left ventricular ejection fraction. Conclusions: In this pilot study of patients with nonischemic cardiomyopathy, itMSC therapy was safe, caused immunomodulatory effects, and was associated with improvements in health status and functional capacity. Clinical Trial Registration: URL: . Unique identifier: [NCT02467387][1]. # Novelty and Significance {#article-title-23} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT02467387&atom=%2Fcircresaha%2F120%2F2%2F332.atomRationale: Potential benefits of mesenchymal stem cell (MSC) therapy in heart failure may be related to paracrine properties and systemic effects, including anti-inflammatory activities. If this hypothesis is valid, intravenous administration of MSCs should improve outcomes in heart failure, an entity in which excessive chronic inflammation may play a pivotal role. Objective: To assess the safety and preliminary efficacy of intravenously administered ischemia-tolerant MSCs (itMSCs) in patients with nonischemic cardiomyopathy. Methods and Results: This was a single-blind, placebo-controlled, crossover, randomized phase II-a trial of nonischemic cardiomyopathy patients with left ventricular ejection fraction ⩽40% and absent hyperenhancement on cardiac magnetic resonance imaging. Patients were randomized to intravenously administered itMSCs (1.5×106 cells/kg) or placebo; at 90 days, each group received the alternative treatment. Overall, 22 patients were randomized to itMSC (n=10) and placebo (n=12) at baseline. After crossover, data were available for 22 itMSC patients. No major differences in death, hospitalization, or serious adverse events were noted between the 2 treatments. Change from baseline in left ventricular ejection fraction and ventricular volumes was not significantly different between therapies. Compared with placebo, itMSC therapy increased 6-minute walk distance (+36.47 m, 95% confidence interval 5.98–66.97; P=0.02) and improved Kansas City Cardiomyopathy clinical summary (+5.22, 95% confidence interval 0.70–9.74; P=0.02) and functional status scores (+5.65, 95% confidence interval −0.11 to 11.41; P=0.06). The data demonstrated MSC-induced immunomodulatory effects, the magnitude of which correlated with improvement in left ventricular ejection fraction. Conclusions: In this pilot study of patients with nonischemic cardiomyopathy, itMSC therapy was safe, caused immunomodulatory effects, and was associated with improvements in health status and functional capacity. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02467387.

AN AGGREGATE OF PATHWAY-RELATED BIOMARKERS PREDICT RISK OF ACUTE MYOCARDIAL INFARCTION AND DEATH

Activation of diverse pathophysiologic processes that include thrombotic, inflammatory, and immune pathways contribute to plaque rupture and adverse outcomes in CAD. We hypothesized that an aggregate biomarker risk score comprised of C-reactive protein (CRP), fibrin degradation products (FDP),