Lee, Joon Sup

Background: Refractory angina(Ang) effects 150 –250,000 pts in the US alone. These individuals have exhausted options for revasc and continue to have lifestyle limiting ang despite optimal medical Rx. Pre-clinical studies provided evidence that human CD34+ cells(CD34) can stimulate new blood vessel formation in ischemic myocardium(Myo), improving perfusion and function. We performed a phase 2 study of intraMyo injection of autologous CD34 in pts with CCS Class 3 and 4 Ang to obtain evidence for feasibility, safety and bioactivity. Methods: A phase 2 randomized, double-blind, placebo-controlled clinical trial was performed at 26 centers in the United States. There were 3 treatment groups: placebo, low dose (1×10^5 CD34/kg body wt) and high dose (5×10^5 CD34/kg). All pts underwent mobilization with GCSF 5 mcg/kg/day SC for 5 d, followed by apheresis on d5 to collect mononuclear cells. On day 6 CD34 were purified from the collected cells using the Isolex 300i device. After lot release testing, CD34 were injected endocardially at 10 locations in the ischemic Myo using the Myostar catheter following NOGA mapping. Placebo injections consisted of identical volumes of the diluent only. Results: A total of 167 pts were randomized and completed the injection procedure and 162 completed the 6 mo evaluation. The mean age of subjects was 61.0±8.9, there were 22 female and 145 male subjects. Trop was elevated in 26 pts at baseline and in 71 at some point following GCSF or injection. At 6 mo CD34 treated pts showed more reduction in ang frequency (−8.6 placebo vs 14.2 low dose) and improved ETT time (+69 sec placebo vs. +138 low dose). At 12m CD34 treated continue to show more reduction in angina (−8.2 placebo vs. −15.0 low dose) and improved ETT (+58 sec placebo vs. + 139 sec low dose). For key endpoints the high dose group results were inferior to low dose. The 12m data set has been locked and is being analyzed and the results of the completed analysis will be presented. Conclusions: Autologous CD34 cell therapy was associated with improved exercise tolerance and reduced angina in no-option pts with intractable angina. Ongoing analysis will determine endpoints, sample size and suitability of this therapy for a phase III study in no-option pts with refractory angina.

Importance In patients with severe aortic valve stenosis at intermediate surgical risk, transcatheter aortic valve replacement (TAVR) with a self-expanding supra-annular valve was noninferior to surgery for all-cause mortality or disabling stroke at 2 years. Comparisons of longer-term clinical and hemodynamic outcomes in these patients are limited. Objective To report prespecified secondary 5-year outcomes from the Symptomatic Aortic Stenosis in Intermediate Risk Subjects Who Need Aortic Valve Replacement (SURTAVI) randomized clinical trial. Design, Setting, and Participants SURTAVI is a prospective randomized, unblinded clinical trial. Randomization was stratified by investigational site and need for revascularization determined by the local heart teams. Patients with severe aortic valve stenosis deemed to be at intermediate risk of 30-day surgical mortality were enrolled at 87 centers from June 19, 2012, to June 30, 2016, in Europe and North America. Analysis took place between August and October 2021. Intervention Patients were randomized to TAVR with a self-expanding, supra-annular transcatheter or a surgical bioprosthesis. Main Outcomes and Measures The prespecified secondary end points of death or disabling stroke and other adverse events and hemodynamic findings at 5 years. An independent clinical event committee adjudicated all serious adverse events and an independent echocardiographic core laboratory evaluated all echocardiograms at 5 years. Results A total of 1660 individuals underwent an attempted TAVR (n = 864) or surgical (n = 796) procedure. The mean (SD) age was 79.8 (6.2) years, 724 (43.6%) were female, and the mean (SD) Society of Thoracic Surgery Predicted Risk of Mortality score was 4.5% (1.6%). At 5 years, the rates of death or disabling stroke were similar (TAVR, 31.3% vs surgery, 30.8%; hazard ratio, 1.02 [95% CI, 0.85-1.22]; P = .85). Transprosthetic gradients remained lower (mean [SD], 8.6 [5.5] mm Hg vs 11.2 [6.0] mm Hg; P < .001) and aortic valve areas were higher (mean [SD], 2.2 [0.7] cm 2 vs 1.8 [0.6] cm 2 ; P < .001) with TAVR vs surgery. More patients had moderate/severe paravalvular leak with TAVR than surgery (11 [3.0%] vs 2 [0.7%]; risk difference, 2.37% [95% CI, 0.17%- 4.85%]; P = .05). New pacemaker implantation rates were higher for TAVR than surgery at 5 years (289 [39.1%] vs 94 [15.1%]; hazard ratio, 3.30 [95% CI, 2.61-4.17]; log-rank P < .001), as were valve reintervention rates (27 [3.5%] vs 11 [1.9%]; hazard ratio, 2.21 [95% CI, 1.10-4.45]; log-rank P = .02), although between 2 and 5 years only 6 patients who underwent TAVR and 7 who underwent surgery required a reintervention. Conclusions and Relevance Among intermediate-risk patients with symptomatic severe aortic stenosis, major clinical outcomes at 5 years were similar for TAVR and surgery. TAVR was associated with superior hemodynamic valve performance but also with more paravalvular leak and valve reinterventions.

An increasing number of patients have refractory angina despite optimal medical therapy and are without further revascularization options. Preclinical studies indicate that human CD34 + stem cells can stimulate new blood vessel formation in ischemic myocardium, improving perfusion and function. In ACT34-CMI ( N = 167), patients treated with autologous CD34 + stem cells had improvements in angina and exercise time at 6 and 12 months compared to placebo; however, the longer-term effects of this treatment are unknown. ACT34 was a phase II randomized, double-blind, placebo-controlled clinical trial comparing placebo, low dose (1 × 10 5 CD34/kg body weight), and high dose (5 × 10 5 CD34/kg) using intramyocardial delivery into the ischemic zone following NOGA ® mapping. To obtain longer-term safety and efficacy in these patients, we compiled data of major adverse cardiac events (MACE; death, myocardial infarction, acute coronary syndrome, or heart failure hospitalization) up to 24 months as well as angina and quality of life assessments in patients who consented for 24-month follow-up. A total of 167 patients with class III–IV refractory angina were randomized and completed the injection procedure. The low-dose-treated patients had a significant reduction in angina frequency ( p = 0.02, 0.035) and improvements in exercise tolerance testing (ETT) time ( p = 0.014, 0.017) compared to the placebo group at 6 and 12 months. At 24 months, patients treated with both low-and high-dose CD34 + cells had significant reduction in angina frequency ( p = 0.03). At 24 months, there were a total of seven deaths (12.5%) in the control group versus one (1.8%) in the low-dose and two (3.6%) in the high-dose ( p = 0.08) groups. At 2 years, MACE occurred at a rate of 33.9%, 21.8%, and 16.2% in control, low-, and high-dose patients, respectively ( p = 0.08). Autologous CD34 + cell therapy was associated with persistent improvement in angina at 2 years and a trend for reduction in mortality in no-option patients with refractory angina.