Stem Cell News: Acute Respiratory Distress Syndrome

Human Clinical Articles

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Umbilical cord mesenchymal stem cells for COVID‐19 acute respiratory distress syndrome: A double‐blind, phase 1/2a, randomized controlled trial

Abstract

Acute respiratory distress syndrome (ARDS) in COVID‐19 is associated with high mortality. Mesenchymal stem cells are known to exert immunomodulatory and anti‐inflammatory effects and could yield beneficial effects in COVID‐19 ARDS. The objective of this study was to determine safety and explore efficacy of umbilical cord mesenchymal stem cell (UC‐MSC) infusions in subjects with COVID‐19 ARDS. A double‐blind, phase 1/2a, randomized, controlled trial was performed. Randomization and stratification by ARDS severity was used to foster balance among groups. All subjects were analyzed under intention to treat design. Twenty‐four subjects were randomized 1:1 to either UC‐MSC treatment (n = 12) or the control group (n = 12). Subjects in the UC‐MSC treatment group received two intravenous infusions (at day 0 and 3) of 100 ± 20 × 106 UC‐MSCs; controls received two infusions of vehicle solution. Both groups received best standard of care. Primary endpoint was safety (adverse events [AEs]) within 6 hours; cardiac arrest or death within 24 hours postinfusion). Secondary endpoints included patient survival at 31 days after the first infusion and time to recovery. No difference was observed between groups in infusion‐associated AEs. No serious adverse events (SAEs) were observed related to UC‐MSC infusions. UC‐MSC infusions in COVID‐19 ARDS were found to be safe. Inflammatory cytokines were significantly decreased in UC‐MSC‐treated subjects at day 6. Treatment was associated with significantly improved patient survival (91% vs 42%, P = .015), SAE‐free survival (P = .008), and time to recovery (P = .03). UC‐MSC infusions are safe and could be beneficial in treating subjects with COVID‐19 ARDS.

Lessons learned

  • Two intravenous infusions of umbilical cord mesenchymal stem cells (UC‐MSCs), at a dose of 100 million cells per infusion, given 72 hours apart, are safe in COVID‐19 patients with acute respiratory distress syndrome.
  • This double blind randomized controlled trial in 24 subjects demonstrated fewer serious adverse events in the UC‐MSC treatment group compared with the control group.
  • UC‐MSC treatment was associated with a significant decrease in a set of inflammatory cytokines involved in the COVID‐19 “cytokine storm.”
  • UC‐MSC treatment was associated with significantly improved patient survival and time to recovery.
  • The observed findings strongly support further investigation in a larger trial designed to estimate and establish efficacy.

Significance statement

This study was a double‐blind, randomized, controlled, early phase clinical trial of umbilical cord mesenchymal stem cell treatment in 24 subjects with COVID‐19 acute respiratory distress syndrome. This study demonstrated fewer serious adverse events in the treatment group compared with control. Exploratory efficacy analyses provide evidence of significantly improved patient survival and time to recovery. The observed findings strongly support further investigation in a larger trial designed to estimate and establish efficacy. These observations will inform physicians influencing clinical practice and future research in the fields of acute respiratory distress syndrome, COVID‐19, and other immune‐related disorders.

1 INTRODUCTION

Coronavirus disease 2019 (COVID‐19), a pneumonia‐like disease caused by the virus severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), reached pandemic proportions in early 2020.1, 2 A subset of subjects infected by SARS‐CoV‐2 develop severe COVID‐19 requiring hospitalization.3, 4 Severe COVID‐19 is believed to result from hyperinflammation, overactive immune response triggering cytokine storm, and a prothrombotic state, collectively determined as immunothrombosis, all elicited by SARS‐CoV‐2 infection.58 Subjects progressing to acute respiratory distress syndrome (ARDS) require high‐flow oxygen therapy, intensive care, and frequently, mechanical ventilation.3, 4, 912 Mortality in patients with COVID‐19 and ARDS was reported to be 52.4%.10 There is an urgent need for novel therapies that can attenuate the excessive inflammatory response associated with the immunopathological cytokine storm and immunothrombosis, that can accelerate the recovery of functional lung tissue, and that can abate mortality in patients with severe COVID‐19.

Mesenchymal stem cells, also known as mesenchymal stromal cells or medicinal signaling cells (MSCs),13 have been shown to modulate overactive immune and hyperinflammatory processes, promote tissue repair, and secrete antimicrobial molecules.1416 These cells, with established safety profile when administered intravenously,17 have been studied for treatment of autoimmune diseases (eg, type 1 diabetes [T1D]),18, 19 systemic lupus erythematous,20 inflammatory disorders,21 and steroid‐refractory graft‐vs‐host‐disease (GvHD).22 MSCs have been reported to limit inflammation and fibrosis in the lungs,23, 24 and have generated variable yet promising results in ARDS of viral25 and nonviral etiology.2629 Multiple ongoing trials are now testing MSCs in patients with severe COVID‐19, and pilot uncontrolled trials have reported promising results.16, 3034 MSCs can be isolated and expanded from multiple tissues, including the umbilical cord (UC). UC‐MSCs constitute a cell type of choice in cell therapy trials, including for COVID‐19.15, 3035 The experience accumulated thus far indicates that allogeneic UC‐MSC administration is safe in a multitude of diseases.36 These cells can be derived from umbilical cords discarded after delivery and quickly expanded to clinically relevant numbers.37 They express low levels of class I and class II human leukocyte antigen, which may reduce alloreactivity.37 Our Current Good Manufacturing Practice (cGMP) manufacturing facility is now scaling up UC‐MSC manufacturing to support upcoming multisite clinical trials, where large numbers of cell doses will be required.

The objective of this study was to establish safety and explore efficacy of allogenic UC‐MSC infusions in hospitalized patients with ARDS secondary to COVID‐19. Here we report the results at 1 month of follow‐up of a double‐blind randomized controlled trial (RCT) testing this cell‐based therapy approach.

2 MATERIALS AND METHODS

2.1 Trial design

This double‐blind, phase 1/2a randomized controlled trial was an academic, investigator‐initiated trial performed at UHealth System/Jackson Health System (UHS/JHS), in Miami, Florida. This trial was designed to evaluate safety and explore efficacy endpoints of allogeneic UC‐MSCs in patients with COVID‐19 and ARDS.

Regulatory, ethical, and institutional review board approvals were obtained by the Western Institutional Review Board and UHS/JHS Human Subject Research Office/Institutional Review Board in accordance with local institutional requirements.

Additional details are provided in the supplemental online Methods.

2.2 Participants

The trial was conducted in accordance with the principles of the Declaration of Helsinki and consistent with the Good Clinical Practice guidelines of the International Conference on Harmonisation.

Subjects diagnosed with COVID‐19 ARDS were eligible for inclusion if they met the eligibility criteria listed in Table S1 within 24 hours of enrollment. The investigations were performed with informed consent.

2.3 Randomization

Twenty‐four subjects hospitalized for COVID‐19 were randomized 1:1 to either UC‐MSC treatment (n = 12) or to the control group (n = 12). Patients were assigned to treatment group using a stratified, blocked randomized design.

Additional details are provided in the supplemental online Methods.

2.4 Blinding

The study was double‐blinded: neither the patient nor the assessing physician was aware of treatment assignment, and the staff responsible for product administration were blinded to group assignment.

2.5 UC‐MSC investigational product

UC‐MSCs were manufactured as previously described.38 UC‐MSCs were culture‐expanded from a previously established and characterized master cell bank (MCB) derived from the subepithelial lining of a UC, collected from a healthy term delivery (kindly provided by Jadi Cell and Amit Patel, M.D.).37, 39 The MCB and its source tissue were tested according to the applicable U.S. Food and Drug Administration (FDA) regulations and American Association of Blood Banks (AABB) and Foundation for the Accreditation for Cellular Therapy (FACT) standards for cellular therapies.

In preparation for infusion, frozen UC‐MSCs were quickly thawed and slowly diluted in Plasma‐LyteA supplemented with human serum albumin and heparin (vehicle solution). The final volume of UC‐MSC suspension or vehicle solution (control) for infusion was 50 mL. Cell dose (100 ± 20 × 106), cell viability by trypan blue (>80%), cell surface marker expression by flow cytometric analysis (CD90/CD105 > 95%, CD34/CD45 < 5%), endotoxin (<1.65 EU/mL), Gram stain (negative), and 14‐day sterility (negative) were used as product release criteria. The vehicle solution was tested for 14‐day sterility, Gram stain, and endotoxin. The UC‐MSC suspension or vehicle solution was infused within 3 hours of preparation for infusion.

Additional details are provided in the supplemental online Methods.

2.6 Interventions

Subjects in the UC‐MSC treatment group received two intravenous infusions of 100 ± 20 × 106 UC‐MSCs each, in 50 mL vehicle solution containing human serum albumin and heparin, infused over 10 ± 5 minutes, at days 0 and 3. Subjects in the control group (n = 12) received two infusions of 50 mL vehicle solution, at day 0 and day 3. Best standard of care was provided in both groups following the current institutional COVID‐19 guidelines.

Additional details are provided in the supplemental online Methods.

2.7 Outcomes

2.7.1 Primary endpoints

Primary endpoints were the following: (a) safety, defined by the occurrence of prespecified infusion‐associated adverse events (AEs) within 6 hours from each infusion; (b) cardiac arrest or death within 24 hours postinfusion; and (c) incidence of AEs.

2.7.2 Secondary endpoints

Secondary endpoints included exploratory efficacy defined by clinical outcomes and laboratory testing and mechanistic analyses.

Clinical outcomes included the following: (a) survival at day 28 after treatment; (b) time to recovery, defined as time to discharge or, if the subject was hospitalized, no longer requiring supplemental oxygen and no longer requiring COVID‐19‐related medical care; and (c) AEs, serious AEs (SAEs), and clinical outcomes assessed for 31 days after the first infusion, corresponding to 28 days after the last infusion.

Laboratory testing and mechanistic analyses included the following: (a) viral load by SARS‐CoV‐2 real‐time polymerase chain reaction (RT‐PCR) in peripheral blood plasma samples and (b) inflammatory cytokines, chemokines, and growth factors in peripheral blood plasma.

Primary and secondary endpoints are presented in detail in the supplemental online Methods.

2.8 Plasma preparation from peripheral blood

Whole blood was collected from randomized subjects at day 0 (immediately pretreatment) and at day 6 after treatment initiation. Whole blood was collected into EDTA‐treated tubes, transferred on ice, and processed for plasma separation within 4 hours. Whole blood was centrifuged at 2000g for 15 minutes at 4°C. The plasma (top fraction) was collected, aliquoted into cryogenic tubes, and stored at −80°C until processing.

2.9 Analysis of viral load by SARS‐CoV‐2 RT‐PCR

The RealStar SARS‐COV‐2 RT‐PCR kit (Altona Diagnostics GmbH, Hamburg, Germany) was used to detect the SARS‐CoV‐2‐specific S gene and quantify the number of copies per mL of plasma. The assay was performed following the manufacturer’s instruction, using plasma samples collected from the randomized subjects on day 0 and day 6.

2.10 Analysis of inflammatory cytokines, chemokines, and growth factors in peripheral blood plasma

A protein array (RayBio Q‐Series, RayBiotech, Peachtree Corners, Georgia) was used to determine plasma levels of a set of inflammatory cytokines, chemokines, and growth factors (granulocyte‐macrophage colony‐stimulating factor [GM‐CSF], interferon [IFN]g, interleukin [IL]‐2, IL‐5, IL‐6, IL‐7, tumor necrosis factor [TNF]a, TNFb, platelet‐derived growth factor [PDGF]‐BB, regulated on activation, normal T cell expressed and secreted, RANTES). The assay was performed using plasma samples collected from the randomized subjects on day 0 and day 6. On the processing day, 1 mL of plasma per sample was thawed in a 37°C water bath and supplemented with 10 μL of 100× Halt Protease and Phosphatase inhibitor cocktail (Thermo Fisher Scientific, Waltham, Massachusetts). Each plasma sample was diluted 1:2 with sample diluent and assayed following the manufacturer’s instructions. The fluorescent signals were visualized via a laser scanner equipped with a Cy3 wavelength (green channel) and converted to concentrations (pg/mL) using the standard curve generated per array.

2.11 Statistical methods

Comparisons of AEs, SAEs, demographics, clinical characteristics, comorbidities, and concomitant treatments between the two groups were performed using Fisher’s exact test and Wilcoxon two‐sample tests for categorical and continuous variables, respectively. Survival, survival in absence of SAE (SAE‐free survival), and time to recovery were estimated in each group with Kaplan‐Meier survival estimates. Log‐rank tests were used to compare hazards between groups. For the analyses of viral load, P values were calculated using the Wilcoxon rank‐sum test on SAS 9.4. The data were nonnormally distributed. For the analyses of inflammatory cytokines, chemokines, and growth factors, group data at a specific day were analyzed via nonparametric unpaired Mann‐Whitney t test; for the analyses on longitudinal changes in each group, data at day 0 and day 6 were analyzed via nonparametric paired Wilcoxon t test.

2.12 Registration

This trial was registered with ClinicalTrials.gov identifier NCT04355728 (https://clinicaltrials.gov/ct2/show/NCT04355728?term=NCT04355728&draw=2&rank=1).

2.13 Clinical trial protocol

The clinical trial protocol is included in the Data S1.

3 RESULTS

3.1 Participant flow

Participant flow is shown in Figure 1.

image
Enrollment and randomization. UC‐MSC, umbilical cord mesenchymal stem cell

3.2 Recruitment

From 25 April 2020, to 21 July 2020, a total of 28 subjects were enrolled. Four subjects were subsequently determined to be ineligible because of screen failure. Twenty‐four subjects were randomized (Figure 1). At enrollment, 11 subjects (46%) were receiving invasive mechanical ventilation, and 13 (54%) were on high flow oxygen therapy via noninvasive ventilation (including high flow nasal cannula, continuous positive airways pressure, or bilevel positive airways pressure) prior to initiation of treatment.

Demographics and baseline characteristics for enrolled subjects, along with stratification, randomization, and concomitant treatment information are presented in Table 1 and Table S2.

TABLE 1. Baseline characteristics and concomitant treatments during index of hospitalization by treatment group
Characteristics and treatments UC‐MSC (n = 12) Control (n = 12) P value
Sex, n (%) .41
Male 5 (41.7) 8 (66.7)
Female 7 (58.3) 4 (33.3)
Age, mean ± SD, years 58.58 ± 15.93 58.83 ± 11.61 .97
Race, n (%) 0.99
White 11 (91.7) 10 (83.3)
African American 1 (8.3) 2 (16.7)
Ethnicity, n (%) 0.99
Hispanic or Latino 11 (91.7) 11 (91.7)
Non‐Hispanic 1 (8.3) 1 (8.3)
PaO2/FiO2 ratio at enrollment, median (IQR) 124 (68‐164) 108.5 (68.5‐165.5) .67
ARDS severity stratification, n (%) 0.99
Mild‐to‐moderate 3 (25) 3 (25)
Moderate‐to‐severe 9 (75) 9 (75)
BMI, mean ± SD, kg/m2 34.5 ± 4.5 29.6 ± 3.5 .01
Smoker (former), n (%) 0 2 (16.7) .48
Comorbidities, n (%)
Diabetes 5 (41.7) 6 (50) 0.99
Hypertension 7 (58.3) 9 (75) .67
Obesity (BMI >30) 11 (91.7) 5 (41.7) .03
Cancer 0 1 (8.3) 0.99
Heart disease 1 (8.3) 3 (25) .59
Concomitant treatments, n (%)
Heparin 12 (100) 12 (100) 0.99
Only prophylactic dose heparina 9 (75) 7 (58.3) .67
Therapeutic dose heparinb 3 (25) 5 (41.7) .67
Remdesivir 9 (75) 7 (58.3) .67
Convalescent plasma 3 (25) 4 (33.3) 0.99
Corticosteroids 10 (83.3) 9 (75) 0.99
Tocilizumab 1 (8.3) 4 (33.3) .32
Hydroxychloroquine 1 (8.3) 2 (18.2) .59
Alteplase 0 2 (16.7) .48
  • Note: Age and BMI are normally distributed. PaO2/FiO2 ratio at enrollment is non‐normally distributed. t test, Wilcoxon two‐sample test, and Fisher’s exact test were used for continuous normal, continuous non‐normal and categorical variables, respectively.
  • Abbreviations: ARDS, acute respiratory distress syndrome; BMI, body mass index; FiO2, fraction of inspired oxygen; IQR, interquartile range; PaO2, partial pressure of oxygen; UC‐MSC, umbilical cord mesenchymal stem cell.
  • a Prophylactic dose heparin: either prophylactic unfractionated heparin, subcutaneous injection, 5000 units two to three times daily (up to 15 000 units) or prophylactic enoxaparin 40 to 60 mg daily.
  • b Therapeutic dose heparin: either full dose unfractionated heparin, intravenous, titrated to a goal of activated partial thromboplastin time, or full dose enoxaparin 1 mg/kg twice daily.

Two cases required special considerations. Subject #11 died for reasons unrelated to COVID‐19 after failed endotracheal intubation. Therefore, this subject was considered as censored in the data analysis for time to COVID‐19‐related death and time to recovery outcomes. Subject #24 left the hospital against medical advice 11 days after second infusion and was thus considered as censored in the time to recovery analysis. This patient eventually recovered at home and was confirmed alive at 31 days after the first infusion.

A Data Safety Monitoring Board reviewed all safety data.

At the time of this writing, all subjects have been followed for 31 days after the first infusion, corresponding to 28 days after the second infusion.

3.3 Baseline data

Twelve subjects were randomized to the UC‐MSC treatment group (age 59 ± 16 years; 7 women [58%]) and 12 to the control group (age 59 ± 12 years; 4 women [33%]) (Table 1; Table S2). The age of enrolled subjects was 59 ± 14 years (mean ± SD).

Three subjects in each group were stratified to the mild‐to‐moderate ARDS severity stratum, and nine subjects in each group into the moderate‐to‐severe stratum. There were no significant differences in concomitant treatments between the groups (Table 1; Table S2). The only differences observed in baseline characteristics and comorbidities were in body mass index and obesity, which were higher in the UC‐MSC treatment group (Table 1; Table S2). The analysis was by original assigned groups.

3.4 Investigational product

An average of 98.7 × 106 UC‐MSCs were administered per infusion. The viability of UC‐MSCs (investigational product) at the time of product release for administration was found to be 96.2% ± 1.8% by trypan blue and 88.4% ± 7.6% by flow cytometry using fixable viability stain. Apoptosis, assessed by activated caspase‐3, was found to be 2.4% ± 3.7%, by flow cytometry (Figure S1). No differences in cell dose, cell viability, or degree of apoptosis were observed between UC‐MSCs (investigational product) prepared for the first or second infusion. Stability studies demonstrated stability of the UC‐MSC investigational product for up to 8 hours after thawing and preparation, as assessed by cell count, viability by trypan blue and flow cytometry, and apoptosis assessed by flow cytometry. Cell surface marker analysis demonstrated a typical surface marker profile characteristic of MSCs: CD90 of 97.9% ± 2.6%, CD105 of 98.1% ± 1.4%, and CD34/CD45 of 2.2% ± 4.9% (Figure S1).

3.5 Outcomes and estimations

A total of nine deaths were documented by day 28 after the second infusion. Two deaths occurred in the UC‐MSC treatment group and seven deaths in the control group. One subject (Subject #11) in the UC‐MSC treatment group died as a result of a failed endotracheal intubation. This outcome was deemed to be unrelated to the patient’s COVID‐19 disease. Therefore, data analyses for this subject were censored at the time of failed endotracheal intubation.

The details of all deaths are presented in Table S3.

3.6 Adverse events

Two serious adverse events (SAEs) were observed in the UC‐MSC group and 16 SAEs in the control group, affecting 2 of 12 and 8 of 12 subjects, respectively (P = .04; Fisher’s exact test). There were significantly more subjects experiencing SAEs in the control group than in the UC‐MSC treatment group. The adverse events in all subjects are summarized in Table 2.

TABLE 2. Summary of all adverse events for randomized subjects
Topics UC‐MSC treatment, n (%) Controls, n (%) Total (n = 24; 12 per group), n (%) Fisher’s exact test
Number of AEs reported 35 53 88
Number of subjects with AEsa 8 11 19 NS
Number of SAEs reported 2 16 18
Number of subjects with SAEsa 2 8 10 P = .04
Number of AEs by severityb
Mild 13 (37) 13 (24) 26 (30)
Moderate 18 (51) 21 (40) 39 (44)
Severe 4 (12) 19 (36) 23 (26)
Subjects with AEs by severityc,d
Mild 7 (44) 5 (25) 12 (33) NS
Moderate 7 (44) 8 (40) 15 (42) NS
Severe 2 (12) 7 (35) 9 (25) NS
Number of AEs by relatedness to treatmentb
Unrelated 31 (89) 45 (85) 76 (86)
Unlikely 3 (9) 7 (13) 10 (11)
Possible 1 (3) 1 (2) 2 (3)
Probable 0 (0) 0 (0) 0 (0)
Definite 0 (0) 0 (0) 0 (0)
Subjects with AEs by relatedness to treatmentc,d
Unrelated 8 (80) 10 (67) 18 (72) NS
Unlikely 1 (10) 4 (26) 5 (20) NS
Possible 1 (10) 1 (7) 2 (8) NS
Probable 0 (0.0) 0 (0.0) 0 (0.0) NS
Definite 0 (0.0) 0 (0.0) 0 (0.0) NS
  • Abbreviations: AE, adverse event; SAE, serious adverse event; NS, not significant; UC‐MSC, umbilical cord mesenchymal stem cell.
  • a Subjects who experience one or more AEs or SAEs are counted only once.
  • b Percentages are based on number of AEs reported for each treatment group.
  • c Subjects are counted only once within a particular severity grade or relatedness category.
  • d Percentages are based on n for each treatment group.

3.7 Primary endpoint

The primary endpoint was safety, defined as the occurrence of prespecified infusion‐associated AEs within 6 hours after infusion in addition to cardiac arrest or death within 24 hours after infusion. Prespecified infusion‐associated AEs are outlined in Table 3. One subject in each group developed infusion‐associated AEs. UC‐MSC treatment was found to be safe, as it did not lead to an increase in prespecified infusion‐associated AEs. In the UC‐MSC treatment group, the only reported adverse event occurred in a subject with bradycardia, who experienced worsening of bradycardia and required transient vasopressor treatment. In the control group, all prespecified infusion‐associated AEs occurred in the same subject, who experienced cardiac arrest 2 hours after infusion of vehicle solution. In each group, one subject developed infusion‐associated AEs.

TABLE 3. Primary endpoint: Safety
Adverse event Adverse events
UC‐MSC treatment (n = 12), n (%) Control (n = 12), n (%)
1a. An increase in vasopressor dose 1a 1
1b. In patients receiving mechanical ventilation: worsening hypoxemia 0 0
1c. In patients receiving high flow oxygen therapy: worsening hypoxemia, as indicated by requirement of intubation and mechanical ventilation 0 0
1d. New cardiac arrhythmia requiring cardioversion 0 1
1e. New ventricular tachycardia, ventricular fibrillation, or asystole 0 1
1f. A clinical scenario consistent with transfusion incompatibility or transfusion‐related infection 0 0
2. Cardiac arrest or death within 24 h postinfusion 0 0
  • Note: Safety: as defined by the occurrence of prespecified infusion‐associated adverse events within 6 hours (1a‐1f) and occurrence of cardiac arrest or death within 24 hours postinfusion (2).
  • a The vasopressor dose increase was ordered by the primary treating physician before the infusion started, but it was not given until hours later, after the infusion.

3.8 Secondary endpoints

At 31 days after the first infusion (corresponding to 28 days after the last infusion), patient survival was significantly improved in the UC‐MSC vs the control group: 10 of 11 (91%) vs 5 of 12 (42%), respectively (P = .015). The hazard ratio for death comparing the control group with UC‐MSC treatment group was 8.76 (95% confidence interval [CI]: 1.07‐71.4), indicating that the control group had a higher risk of death. Kaplan‐Meier estimates are presented in Figure 2A (survival).

image
Kaplan‐Meier curves. A, Survival. At 31 days after the first infusion (corresponding to 28 days after the last infusion), patient survival was 91% vs 42% in the UC‐MSC and control group, respectively (P = .015). The difference between the groups was statistically significant. B, SAE‐free survival. SAE‐free survival was significantly improved in the UC‐MSC treatment group compared with the control group (P = .008). SAEs affected two vs eight patients in the UC‐MSC and control group, respectively. C, Time to recovery. Time to recovery was significantly shorter in the UC‐MSC treatment group compared with the control group (P = .031). Censoring was limited to dropout from study, and the event of interest was recovery. In the case of death, the patient’s time to recovery was considered censored at the end of study observation; thus the patient conservatively remained in the risk set for all Kaplan‐Meier estimation throughout the study period. CI, confidence interval; HR, hazard ratio; SAE, serious adverse event; UC‐MSC, umbilical cord mesenchymal stem cell

SAE‐free survival was significantly improved in the UC‐MSC treatment group (P = .0081). The hazard ratio for SAE, comparing the control group with the UC‐MSC treatment group, was 6.22 (95% CI: 1.33‐28.96), indicating that the control group experienced an increased risk of SAEs. Kaplan‐Meier estimates are presented in Figure 2B (SAE‐free survival).

Time to recovery was significantly shorter in the UC‐MSC treatment group (P = .0307). The hazard ratio for recovery comparing the control group with the UC‐MSC treatment group was 0.29 (95% CI: 0.09‐0.95); this is evidence of a lower rate of recovery for the control group. Kaplan‐Meier estimates are presented in Figure 2C (time to recovery).

3.9 Analysis of viral load in peripheral blood plasma

The median viral load at day 0 or day 6 did not differ significantly between the UC‐MSC treatment and control group. The P values were .196 and .136 for day 0 and day 6, respectively (Figure S2).

3.10 Analysis of inflammatory cytokines and chemokines levels in peripheral blood plasma

The blood plasma levels of 10 inflammation‐related proteins were assessed by quantitative enzyme‐linked immunosorbent assay in both UC‐MSC treatment and control groups on days 0 and 6. Baseline levels of proteins tested were comparable in both UC‐MSC and control groups (Figure 3; day 0 column, unpaired t tests), with the exception of IL‐6, which showed higher baseline levels in the control group (P < .05, an imbalance between groups possibly resulting from the small sample size). At 6 days after treatment initiation, we observed significant differences between the groups, and a consistent decrease in inflammatory markers only in the UC‐MSC treatment group. In a comparison between groups at day 6, we observed significant differences in the concentration of GM‐CSF, IFNg, IL‐5, IL‐6, IL‐7, TNFa, TNFb, PDGF‐BB, and RANTES (P < .05); median values of these molecules were lower in the UC‐MSC group (Figure 3; day 6 column, unpaired t tests). The difference in IL‐2 resulted very close to statistical significance (P = .051) (Figure 3; day 6 column, IL‐2). In the longitudinal analysis, inflammatory cytokine concentrations showed marked and statistically significant decreases from day 0 to day 6 only in the UC‐MSC treatment group (Figure 3; UC‐MSC treatment and control columns, paired t tests).

image
Analysis of inflammatory cytokines, chemokines, and growth factors in plasma of randomized subjects. In the comparison between groups at day 6 and in the longitudinal analysis from day 0 to day 6, inflammatory cytokine concentrations showed marked and statistically significant decreases from day 0 to day 6 only in the UC‐MSC treatment group. The overall “signature” of the response in the UC‐MSC treatment group is characterized by a reduction of the levels of key inflammatory molecules involved in the COVID‐19 “cytokine storm,” including IFNg, IL‐6, and TNFa cytokines and RANTES chemokine. GM‐CSF and PDGF‐BB also decreased significantly only in the UC‐MSC treatment group. ns, not significant; UC‐MSC, umbilical cord mesenchymal stem cell

4 DISCUSSION

Severe COVID‐19 is believed to result from a hyperinflammatory state and overactive immune response with cytokine storm and immunothrombosis elicited by SARS‐CoV‐2 infection.5, 40, 41 Patients with severe COVID‐19 frequently develop ARDS, which is associated with poor prognosis.4, 40 Mortality in COVID‐19 is associated with ARDS and multiple organ failure.42 Mortality in patients with COVID‐19 and ARDS was reported to be 52.4%.10 Various treatment modalities have been investigated and recently reported, including dexamethasone11 and convalescent plasma.43 Yet, there remains a need for therapies that can modulate the inflammatory response, shorten the course of disease, and further improve survival.

UC‐MSCs may have beneficial effects in patients with severe COVID‐19 by modulating immune responses and altering the immunopathogenic cytokine storm.3032 The cells used in this trial were derived from the subepithelial lining of the umbilical cord and can be rapidly expanded for clinical applications under strict Good Manufacturing Practice conditions.37 UC‐MSCs were reported to be safe in clinical trials in other disease states and have been safely administered across histocompatibility barriers.4446 Because of their immunomodulatory functions, UC‐MSCs have already been tested in the treatment of autoimmune and inflammatory disorders. Clinical applications using UC‐MSCs processed at our cGMP facility have been authorized by the FDA in subjects with T1D (IND#018302) and Alzheimer’s disease (IND#18200).

Several clinical trials have been conducted to test MSCs as treatment of ARDS, mainly focused on determining safety.2529 Variable results have been reported, possibly because of differences in trial design and quality of the cell product used. Improved outcomes were recently reported in patients with COVID‐19 pneumonia treated with angiotensin converting enzyme ‐ 2 (ACE‐2)‐negative MSCs.30 Additional pilot studies of UC‐MSCs for COVID‐19 also reported promising results.3133

Based on previous encouraging results by other groups,3033 our experience with cell therapy clinical protocols, and the urgent need to develop effective therapeutic strategies, the purpose of this RCT was to determine safety and explore efficacy of UC‐MSCs for treatment of subjects with ARDS secondary to COVID‐19 (ClinicalTrials.gov identifier: NCT04355728).

The current report presents, for the first time, the results of a double‐blind, phase 1/2a RCT testing UC‐MSCs in 24 subjects with COVID‐19 and ARDS. There was overall balance in the distribution of baseline characteristics, comorbidities, or concomitant treatments between the groups. No serious adverse events related to UC‐MSC infusion were observed. There was no observed difference in number of subjects experiencing infusion‐associated adverse events. At 28 days after the last infusion, patient survival was 91% in the UC‐MSC group and 42% in the control group (P = .015). Two SAEs were reported in the UC‐MSC group and 16 in the control group, affecting two and eight patients, respectively (P = .04). SAE‐free survival (P = .008) and time to recovery (P = .03) were significantly improved in the UC‐MSC treatment group.

This study was not intended as an efficacy trial, but instead as an early phase study to establish safety. We relied on randomization to protect against imbalance in biasing preliminary estimates of efficacy. Stratified, blocked randomization was employed to evenly represent ARDS severity and changing standard of care over time between groups. Even with blocked randomization, confounding may exist because, with small numbers, there is still potential for imbalance. Table 1 and Table S2 illustrate overall balance in the distribution of demographic and clinical factors thought to be associated with COVID‐19 trajectory. The only differences observed at baseline, in body mass index and obesity, would be expected to worsen COVID‐19 outcomes in the UC‐MSC treatment group.47, 48 The viral load at baseline did not differ significantly between the UC‐MSC treatment and the control group. An important change in inclusion criteria is worthy of discussion. The study was initially designed to enroll patients receiving invasive mechanical ventilation. At the time of study inception, there were concerns regarding the potential for high flow oxygen therapy and noninvasive mechanical ventilation to increase aerosolization and infection risk in health care workers. Such concerns led practitioners to avoid these therapies and prompted infection control leadership to restrict them in our study sites. Subsequent studies called these concerns into question,49 and high flow oxygen became broadly used. At that time, it appeared appropriate to include in our trial patients of similar disease severity but who were being treated with a different modality, and on 22 June 2020, we made a change in our inclusion criteria to reflect this. Subsequent studies have shown that high flow oxygen therapy is associated with a reduction in the proportion of patients who receive invasive mechanical ventilation, but no difference in mortality.12 This supports the idea that the change of inclusion criteria did not necessarily alter the severity of patients enrolled but rather just reflects the secular trends and treatment patterns in the care of patients with a novel disease.

The inferences we make from the efficacy results observed in this phase 1/2a trial in 24 subjects, including the outcome of survival, are still subject to limitations of sample size and potential bias because of factors we were not yet aware of. However, results do provide preliminary evidence of a remarkable effect, which substantiates the need for further investigation in a larger, stratified, and adjusted clinical trial. In addition, based on our results and those from previously reported clinical trials, synergistic combination strategies could be explored, with agents that have shown a beneficial effect at similar stages of COVID‐19 disease progression, such as dexamethasone11 and convalescent plasma.43

The overall “signature” of the response in the UC‐MSC treatment group is characterized by a reduction of the levels of key inflammatory molecules involved in the COVID‐19 “cytokine storm,” including IFNg, IL‐6, and TNFa cytokines and RANTES chemokine.50 In parallel, a reduction in GM‐CSF was observed. GM‐CSF is the main activator of the proinflammatory M1 macrophage phenotype; hence, its reduction could lead to macrophage polarization toward alternatively activated M2 macrophages.51 The levels of PDGF‐BB also resulted significantly reduced in the UC‐MSC treatment group. Notably, PDGF‐BB stimulates mesenchymal cell activation, airway smooth muscle cell proliferation and migration, lung fibroblast cytokine production, and activation of nociceptive neurons.5254 Hence, it is possible that the administration of allogeneic MSCs could accelerate the steps of tissue repair in the lungs, decreasing the need for further mesenchymal cell activation.

The positive response in subjects receiving UC‐MSC treatment seems to be more closely associated to a decrease in inflammatory cytokines, rather than a change in viral load.

The observations made in this study could be of assistance for future studies in the field of COVID‐19, ARDS, hyperinflammatory states, overactive immune responses, and autoimmunity. In addition, the preferential targeting of lung tissue after intravenous infusion could make UC‐MSCs particularly appealing for ARDS secondary to trauma, microbial infection, and pulmonary GvHD.

5 CONCLUSION

The results of this trial indicate that UC‐MSC infusions in COVID‐19 with ARDS are safe. Moreover, UC‐MSC treatment was associated with a significant reduction in SAEs, mortality, and time to recovery, compared with controls.

ACKNOWLEDGMENTS

The authors wish to thank the North America’s Building Trades Unions (NABTU), The Cure Alliance, the Diabetes Research Institute Foundation (DRIF), the Barilla Group and Family, the Fondazione Silvio Tronchetti Provera, the Simkins Family Foundation, and Ugo Colombo for funding this clinical trial; Dr. Amit N Patel for the invaluable contributions to UC‐MSC manufacturing and infusion protocols over the years; Jadi Cell for providing the initial UC‐MSC master cell bank (cells provided at no cost by JadiCell ‐ US Patent # 9,803,176 B2) used in this trial, further expanded at the Diabetes Research Institute (DRI) cGMP Facility to generate the Investigational Product; Drs. George Burke and Ronald Goldberg for serving as Medical Monitor and DSMB Chair; the DRI‐Cell Transplant Center cGMP Staff; Joana R.N. Lemos for the help with data analysis; Melissa Willman for the help in experimental design; and the Clinical Translational Research Site at the Miami Clinical and Translational Science Institute (UL1TR000460) from the National Center for Advancing Translational Sciences and the National Institute on Minority Health and Health Disparities. The trial was supported by unrestricted donations from the North America’s Building Trades Unions (NABTU), The Cure Alliance, the Diabetes Research Institute Foundation (DRIF), the Barilla Group and Family, the Fondazione Silvio Tronchetti Provera, the Simkins Family Foundation, and Ugo Colombo. This publication was supported by the Clinical Translational Research Site Grants Number UL1TR000460 and UL1TR002736 from the National Center for Advancing Translational Sciences (NCATS). The contents of this publication are solely the responsibility of the authors and do not necessarily represent the official views of the NIH. The funding sources had no roles in study design, patient recruitment, data collection, data analysis, data interpretation, or writing the report. None of the authors has been paid to write this article by a pharmaceutical company or other agency. The corresponding author had full access to all the data in the study and had final responsibility for the decision to submit this manuscript for publication.

CONFLICT OF INTEREST

The authors declared no potential conflicts of interest.

AUTHOR CONTRIBUTIONS

G.L.: conception/design, collection and/or assembly of data, data analysis and interpretation, manuscript writing, final approval of manuscript; E.L.: conception/design, manuscript writing, final approval of manuscript, other (UC‐MSC manufacture); D.C.: collection and/or assembly of data, manuscript writing, final approval of manuscript; S.M.C.: conception/design, data analysis and interpretation, manuscript writing, final approval of manuscript; R.A.A.: conception/design, manuscript writing, final approval of manuscript, other (implementation of the study); D.K.: collection and/or assembly of data, manuscript writing, final approval of manuscript; A.A.G.: collection and/or assembly of data, manuscript writing, final approval of manuscript, other (implementation of the study), other (clinical monitoring); R.P.: collection and/or assembly of data, manuscript writing, final approval of manuscript, other (implementation of the study), other (clinical monitoring); P.R.: conception/design, collection and/or assembly of data, manuscript writing, final approval of manuscript; A.C.M.: manuscript writing, final approval of manuscript, other (implementation of the study); K.H.: manuscript writing, final approval of manuscript, other (protocol preparation), other (regulatory compliance and coordination); C.A.B.: collection and/or assembly of data, manuscript writing, final approval of manuscript, other (implementation of the study); H.K.: collection and/or assembly of data, manuscript writing, final approval of manuscript, other (implementation of the study); L. Rafkin: manuscript writing, final approval of manuscript, other (protocol preparation), other (regulatory compliance and coordination); D.B.: conception/design, manuscript writing, final approval of manuscript, other (clinical monitoring); A.P. and K.G.: manuscript writing, final approval of manuscript, other (implementation of the study); C.L. and X.W.: manuscript writing, final approval of manuscript, other (UC‐MSC manufacture); A.M.A.M. and S.W.M.: data analysis and interpretation, manuscript writing, final approval of manuscript; L. Roque: manuscript writing, final approval of manuscript, other (protocol preparation), other (regulatory compliance and coordination); B.M.: manuscript writing, final approval of manuscript, other (regulatory compliance and coordination); N.S.K., E.G., X.X., J.T., A.I.C., and M.K.G.: conception/design, manuscript writing, final approval of manuscript; R.A.: conception/design, manuscript writing, final approval of manuscript, other (clinical monitoring); C.R.: conception/design, manuscript writing, final approval of manuscript, other (principal investigator), other (clinical monitoring).

Open Research

Supporting Information
REFERENCES

#10…”Chronic Viral Infections”

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A look back: CIRM funded trial aims to help patients suffering from chronic viral infections

by Yimy Villa

Dr. Michael Pulsipher

All this month we are using our blog and social media to highlight a new chapter in CIRM’s life, thanks to the voters approving Proposition 14. We are looking back at what we have done since we were created in 2004, and also looking forward to the future. Today we look at a way of making blood stem cell transplants safer and more readily available

Blood stem cell transplants have provided lifechanging treatments to individuals.  This statement is observed firsthand in several patients in CIRM funded trials for X-linked Chronic Granulomatous Disease (X-CGD), Sickle Cell Disease (SCD), and Severe Combined Immunodeficiency (SCID).  The personal journeys of Evangelina Padilla-Vaccaro, Evie Junior, and Brenden Whittaker speak volumes for the potential this treatment holds.  In these trials, defective blood stem cells from the patient are corrected outside the body and then returned to the patient in a transplant procedure.

Unfortunately, there is still a certain degree of risk that accompanies this procedure.  Before a blood stem cell transplant can be performed,  diseased or defective blood stem cells in the patient’s bone marrow need to be removed using chemotherapy or radiation to make room for the transplant.  This leaves the patient temporarily without an immune system and at risk for a life-threatening viral infection.  Additionally, viral infections pose a serious risk to patients with immune deficiency disorders, with viruses accounting upwards of 40% of deaths in these patients.

That’s why in October 2017, the CIRM ICOC Board awarded $4.8M to fund a clinical trial conducted by Dr. Michael Pulsipher at the Children’s Hospital of Los Angeles.  Dr. Pulsipher and his team are using virus-specific T cells (VSTs), a special type of cell that plays an important role in the immune response, to treat immunosuppressed or immune deficient patients battling life-threatening viral infections.  This trial includes patients with persistent viral infections after having received a blood stem cell transplant as well as those with immune deficiency disorders that have not yet received a blood stem cell transplant.  The VSTs used in this trial specifically treat cytomegalovirus (CMV), Epstein-Barr virus (EBV), and adenovirus infections.  They are manufactured using cells from healthy donors and are banked so as to be readily available when needed.

One challenge of receiving a stem cell transplant can be finding a patient and donor that are a close or identical match.  This is done by looking at specific human leukocyte antigens (HLA), which are protein molecules we inherit from our parents.  To give you an idea of how challenging this can be, you only have a 25% chance of being an HLA identical match with your sibling.

Because VSTs are temporary soldiers that are administered to fight the viral infection and then disappear, Dr. Pulsipher and his team are using partially HLA-matched VSTs to treat patients in their trial.  Previous studies have indicated that partially HLA-matched T-cells can be effective in treating patients.  The availability of partially HLA-matched VST banks that can be used “off the shelf” improves accessibility and shortens the time for patients to receive VST therapy, which will save lives.

To learn more about Dr. Pulsipher’s work, please view the video below:

#12….Sickle Cell Disease

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Progress in the fight against Sickle Cell Disease

by Kevin McCormack

Last November Marissa Cors, a patient advocate in the fight against Sickle Cell Disease (SCD), told the Stem Cellar “A stem cell cure will end generations of guilt, suffering, pain and early death. It will give SCD families relief from the financial, emotional and spiritual burden of caring someone living with SCD. It will give all of us an opportunity to have a normal life. Go to school, go to work, live with confidence.” With each passing month it seems we are getting closer to that day.

CIRM is funding four clinical trials targeting SCD and another project we are supporting has just been given the green light by the Food and Drug Administration to start a clinical trial. Clearly progress is being made.

Yesterday we got a chance to see that progress. We held a Zoom event featuring Marissa Cors and other key figures in the fight against SCD, CIRM Science Officer Dr. Ingrid Caras and Evie Junior. Evie is a pioneer in this struggle, having lived with sickle cell all his life but now hoping to live his life free of the disease. He is five months past a treatment that holds out the hope of eradicating the distorted blood cells that cause such devastation to people with the disease.

You can listen to his story, and hear about the other progress being made. Here’s a recording of the Zoom event.

#11….”Proposition 14″

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Month of CIRM – Our Therapeutics Team Goes Hunting

by Kevin McCormack

All this month we are using our blog and social media to highlight a new chapter in CIRM’s life, thanks to the voters approving Proposition 14. We are looking back at what we have done since we were created in 2004, and also looking forward to the future. Today we have a guest blog by CIRM Senior Science Officer Lisa Kadyk, outlining how she and her colleagues actively search for the best science to fund.

Lisa Kadyk, Ph.D.

Hi everyone,

This is Lisa Kadyk, a Science Officer from the CIRM Therapeutics team, here to tell you about some of the work our team does to support the CIRM mission of accelerating stem cell treatments to patients with unmet medical needs.  Our job involves seeking out and recruiting great scientists to apply to CIRM and supporting those we fund.

Therapeutics team members manage both the awards that fund the final preclinical studies required before testing a therapeutic in a clinical trial (CLIN1), and the awards that fund the clinical trials themselves (CLIN2).

I mentioned above that we actively recruit new applicants for our CLIN1 and CLIN2 awards – which is not an activity that is typical of most funding agencies – so why and how do we do this?

It all comes down to our mission of accelerating the development of therapies to help patients with unmet medical needs.  It turns out that there are many potential applicants developing cutting edge therapies who don’t know much or anything about CIRM, and the ways we can help them with getting those therapies to the clinic and through clinical trials.    So, to bridge this gap, we Science Officers attend scientific conferences, read the scientific literature and meet regularly with each other to stay abreast of new therapeutic approaches being developed in both academia and industry, with the goal of identifying and reaching out to potential applicants about what CIRM has to offer.

What are some of the things we tell potential applicants about how partnering with CIRM can help accelerate their programs?   First of all, due to the efforts of a very efficient Review team, CIRM is probably the fastest in the business for the time between application and potential funding.  It can be as short as three months for a CLIN1 or CLIN2 application to be reviewed by the external Grants Working Group and approved by the CIRM Board, whereas the NIH (for example) estimates it takes seven to ten months to fund an application.   Second, we have frequent application deadlines (monthly for CLIN1 and CLIN2), so we are always available when the applicant is ready to apply.  Third, we have other accelerating mechanisms in place to help grantees once they’ve received funding, such as the CIRM Alpha Stem Cell Clinics network of six clinical sites throughout California (more efficient clinical trial processes and patient recruitment) and Clinical Advisory Panels (CAPs) – that provide technical, clinical or regulatory expertise as well as patient advocate guidance to the grantee.  Finally, we Science Officers do our best to help every step of the way, from application through grant closeout.

We now feel confident that our recruitment efforts, combined with CIRM’s more efficient funding pipeline and review processes, are accelerating development of new therapies.  Back in 2016, a new CIRM Strategic Plan included the goal of recruiting 50 successful (i.e., funded) clinical trial applicants within five years.  This goal seemed like quite a stretch, since CIRM had funded fewer than 20 clinical trials in the previous ten years.  Fast-forward to the end of 2020, and CIRM had funded 51 new trials in those five years, for a grand total of 68 trials.

Now, with the passage of Proposition 14 this past November, we are looking forward to bringing more cell and gene therapeutic candidates into clinical trials.   If you are developing one yourself, feel free to let us know… or don’t be surprised if you hear from us!

#9…Ooooh….”Regenerative Medicine”

Anticipating the Future of Regenerative Medicine: CIRM’s Alpha Stem Cell Clinics Network

by Yimy Villa

All this month we are using our blog and social media to highlight a new chapter in CIRM’s life, thanks to the voters approving Proposition 14. We are looking back at what we have done since we were created in 2004, and also looking forward to the future. Today we take a deeper dive into CIRM’s Alpha Stem Cell Clinics Network.  The following is written by Dr. Geoff Lomax, Senior Officer of CIRM Therapeutics and Strategic Infrastructure.

The year 2014 has been described as the regenerative medicine renaissance: the European Union approved its first stem cell-based therapy and the FDA authorized ViaCyte’s CIRM funded clinical trial for diabetes. A path forward for stem cell treatments had emerged and there was a growing pipeline of products moving towards the clinic. At the time, many in the field came to recognize the need for clinical trial sites with the expertise to manage this growing pipeline. Anticipating this demand, CIRM’s provided funding for a network of medical centers capable of supporting all aspect of regenerative medicine clinical trials. In 2015, the Alpha Stem Cell Clinics Network was launched to for this purpose.

The Alpha Clinics Network is comprised of leading California medical centers with specific expertise in delivering patient-centered stem cell and gene therapy treatments. UC San Diego, City of Hope, UC Irvine and UC Los Angeles were included in the initial launch, and UC San Francisco and UC Davis entered the network in 2017. Between 2015 and 2020 these sites supported 105 regenerative medicine clinical trials. Twenty-three were CIRM-funded clinical trials and the remaining 82 were sponsored by commercial companies or the Alpha Clinic site. These trials are addressing unmet medical needs for almost every disease where regenerative medicine is showing promise including blindness, blood disorders (e.g. sickle cell disease) cancer, diabetes, HIV/AIDS, neurological diseases among others.

As of spring of 2020 the network had inked over $57 million in contracts with commercial sponsors. High demand for Alpha Clinics reflects the valuable human and technical resources they provide clinical trial sponsors. These resources include:

  • Skilled patient navigators to educate patients and their families about stem cell and gene therapy treatments and assist them through the clinical trial process.
  • Teams and facilities specialized in the manufacturing and/or processing of patients’ treatments. In some instances, multiple Alpha Clinic sites collaborate in manufacturing and delivery of a personalized treatment to the patient.
  • Nurses and clinicians with experience with regenerative medicine and research protocols to effectively deliver treatments and subsequently monitor the patients.

The multi- site collaborations are an example of how the network operates synergistically to accelerate the development of new treatments and clinical trials. For example, the UC San Francisco Alpha Clinic is collaborating with UC Berkeley and the UC Los Angeles Alpha Clinic to develop a CIRM-funded gene therapy for sickle cell disease. Each partner brings a unique expertise to the program that aims to correct a genetic mutilation in the patients’ blood stem cells to effectively cure the disease. Most recently, City of Hope has partnered with UC Irvine and UC San Diego as part of CIRM’s COVID-19 research program to study how certain immune system antibodies might be used as a treatment for respiratory disease in infected patients. In another COVID-19 study, UC Irvine and UC Davis are working with a commercial sponsor to evaluate a treatment for infected adults.

The examples above are a small sample of the variety of collaborations CIRM funding has enabled. As the Alpha Clinics track record grown, sponsors are increasingly coming to California to enable the success of their research programs. Sponsors with trials running across the country have noted a desire to expand their number of Alpha Clinic sties because they consistently perform at the highest level.

Back in 2014, it was hard to imagine over one hundred clinical trials would be served by the CIRM network in just five years. Fortunately, CIRM was able to draw on the knowledge of its internal team, external advisors and the ICOC to anticipate this need and provide California infrastructure to rise to the occasion.

#8 (I Think) Updates Continue…Stem Cellar

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Month of CIRM: Battling COVID-19

by Kevin McCormack

All this month we are using our blog and social media to highlight a new chapter in CIRM’s life, thanks to the people of California approving Proposition 14. We are looking back at what we have done since we were created in 2004, and also looking forward to the future.

Dr. John Zaia, City of Hope stem cell researcher

The news that effective vaccines have been developed to help fight COVID-19 was a truly bright spot at the end of a very dark year. But it will be months, in some countries years, before we have enough vaccines to protect everyone. That’s why it’s so important to keep pushing for more effective ways to help people who get infected with the virus.

One of those ways is in a clinical study that CIRM is funding with City of Hope’s Dr. John Zaia. Dr. Zaia and his team, in partnership with the Translational Genomics Research Institute (TGen) in Flagstaff, Arizona, are using something called convalescent plasma to try and help people who have contracted the virus. Here’s the website they have created for the study.

Plasma is a part of our blood that carries proteins, called antibodies, that help defend our bodies against viral infections. When a patient recovers from COVID-19, their blood plasma contains antibodies against the virus. The hope is that those antibodies can now be used as a potential treatment for COVID-19 to help people who are newly infected.

To carry out the study they are using clinical trial sites around California, including some of the CIRM Alpha Stem Cell Network clinics.

For the study to succeed they’ll first need people who have recovered from the virus to donate blood. That’s particularly appropriate in January because this is National Volunteer Blood Donor Month.

The team has three elements to their approach:

  • A rapid-response screening program to screen potential COVID-19 convalescent plasma donors, particularly in underserved communities.
  • A laboratory center that can analyze the anti-SARS-CoV-2 antibodies properties in COVID-19 convalescent plasma.
  • An analysis of the clinical course of the disease in COVID-19 patients to identify whether antibody properties correlate with clinical benefit of COVID-19 convalescent plasma.

There’s reason to believe this approach might work. A study published this week in the New England Journal of Medicine, found that blood plasma from people who have recovered from COVID-19 can help older adults and prevent them from getting seriously ill with the virus if they get the plasma within a few days of becoming infected.

We are used to thinking of blood donations as being used to help people after surgery or who have been in an accident. In this study the donations serve another purpose, but one that is no less important. The World Health Organization describes blood as “the most precious gift that anyone can give to another person — the gift of life. A decision to donate your blood can save a life, or even several if your blood is separated into its components — red cells, platelets and plasma.”

That plasma could help in developing more effective treatments against the virus. Because until we have enough vaccines for everyone, we are still going to need as much help as we can get in fighting COVID-19. The recent surge in cases throughout the US and Europe are a reminder that this virus is far from under control. We have already lost far too many people. So, if you have recently recovered from the virus, or know someone who has, consider donating blood to this study. It could prove to be a lifesaver.

For more information about the study and how you can be part of it, click here.

#7…”Stem Cellar” Report

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Month of CIRM: Reviewing Review

by Kevin McCormack

Dr. Gil Sambrano, Vice President Portfolio & Review

All this month we are using our blog and social media to highlight a new chapter in CIRM’s life, thanks to the voters approving Proposition 14. We are looking back at what we have done since we were created in 2004, and also looking forward to the future. Today we take a look at our Review team.

Many people who have to drive every day don’t really think about what’s going on under the hood of their car. As long as the engine works and gets them from A to B, they’re happy. I think the same is true about CIRM’s Review team. Many people don’t really think about all the moving parts that go into reviewing a promising new stem cell therapy.

But that’s a shame, because they are really missing out on watching a truly impressive engine at work.

Just consider the simple fact that since CIRM started about 4,000 companies, groups and individuals have applied to us for funding. Just take a moment to consider that number. Four thousand. Then consider that at no time have there been more than 5 people working in the review team. That’s right. Just 5 people. And more recently there have been substantially fewer. That’s a lot of projects and not a lot of people to review them. So how do they do it? Easy. They’re brilliant.

First, as applications come in they are scrutinized to make sure they meet specific eligibility requirements; do they involve stem cells, is the application complete, is it the right stage of research, is the budget they are proposing appropriate for the work they want to do etc. If they pass that initial appraisal, they then move on to the second round, the Grants Working Group or GWG.

The GWG consists of independent scientific experts from all over the US, all over the world in fact. However, none are from California because we want to ensure there are no possible conflicts of interest. When I say experts, I do mean experts. These are among the top in their field and are highly sought after to do reviews with the National Institutes of Health etc.

Mark Noble, PhD, the Director of the Stem Cell and Regenerative Medicine Institute at the University of Rochester, is a long-time member of the GWG. He says it’s a unique group of people:

“It’s a wonderful scientific education because you come to these meetings and someone is putting in a grant on diabetes and someone’s putting in a  grant on repairing the damage to the heart or spinal cord injury or they have a device that will allow you to transplant cells better and there are people  in the room that are able to talk knowledgeably about each of these areas and understand how this plays into medicine and how it might work in terms of actual financial development and how it might work in the corporate sphere and how it fits in to unmet medical needs . I don’t know of any comparable review panels like this that have such a broad remit and bring together such a breadth of expertise which means that every review panel you come to you are getting a scientific education on all these different areas, which is great.”

The GWG reviews the projects for scientific merit: does the proposal seem plausible, does the team proposing it have the experience and expertise to do the work etc. The reviewers put in a lot of work ahead of time, not just reviewing the application, but looking at previous studies to see if the new application has evidence to support what this team hope to do, to compare it to other efforts in the same field. There are disagreements, but also a huge amount of respect for each other.

Once the GWG makes its recommendations on which projects to fund and which ones not to, the applications move to the CIRM Board, which has the final say on all funding decisions. The Board is given detailed summaries of each project, along with the recommendations of the GWG and our own CIRM Review team. But the Board is not told the identity of any of the applicants, those are kept secret to avoid even the appearance of any conflict of interest.

The Board is not required to follow the recommendations of the GWG, though they usually do. But the Board is also able to fund projects that the GWG didn’t place in the top tier of applications. They have done this on several occasions, often when the application targeted a disease or disorder that wasn’t currently part of the agency’s portfolio.

So that’s how Review works. The team, led by Dr. Gil Sambrano, does extraordinary work with little fanfare or fuss. But without them CIRM would be a far less effective agency.

The passage of Proposition 14 means we now have a chance to resume full funding of research, which means our Review team is going to be busier than ever. They have already started making changes to the application requirements. To help let researchers know what those changes are we are holding a Zoom webinar tomorrow, Thursday, at noon PST. If you would like to watch you can find it on our YouTube channel. And if you have questions you would like to ask send them to info@cirm.ca.gov

#6…Read Them All Here!

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Stem cell research reveals path to schizophrenia

by Kevin McCormack

3d illustration of brain nerve cells – Photo courtesy Science Photo

If you don’t know what’s causing a problem it’s hard to come up with a good way to fix it. Mental health is the perfect example. With a physical illness you can see what the problem is, through blood tests or x-rays, and develop a plan to tackle it. But with the brain, that’s a lot harder. You can’t autopsy a brain while someone is alive, they tend to object, so you often only see the results of a neurological illness when they’re dead.

And, says Consuelo Walss-Bass, PhD, a researcher at the University of Texas Health Science Center at Houston (UTHealth), with mental illness it’s even more complicated.

“Mental health research has lagged behind because we don’t know what is happening biologically. We are diagnosing people based on what they are telling us. Even postmortem, the brain tissue in mental health disorders looks perfectly fine. In Alzheimer’s disease, you can see a difference compared to controls. But not in psychiatric disorders.”

So Wals-Bass and her team came up with a way to see what was going on inside the brain of someone with schizophrenia, in real time, to try and understand what puts someone at increased risk of the disorder.

In the study, published in the journal Neuropsychopharmacology, the researchers took blood samples from a family with a high incidence of schizophrenia. Then, using the iPSC method, they turned those cells into brain neurons and compared them to the neurons of individuals with no family history of schizophrenia. In effect, they did a virtual brain biopsy.

By doing this they were able to identify five genes that had previously been linked to a potential higher risk of schizophrenia and then narrow that down further, highlighting one gene called SGK1 which blocked an important signalling pathway in the brain.

In a news release, Walss-Bass says this findings could have important implications in treating patients.

“There is a new antipsychotic that just received approval from the Food and Drug Administration that directly targets the pathway we identified as dysregulated in neurons from the patients, and several other antipsychotics also target this pathway. This could help pinpoint who may respond better to treatments.”

Finding the right treatment for individual patients is essential in helping them keep their condition under control. A study in the medical journal Lancet estimated that six months after first being prescribed common antipsychotic medication, as many as 50% of patients are either taking the drugs haphazardly or not at all. That’s because they often come with unpleasant side effects such as weight gain, drowsiness and a kind of restless anxiety.

By identifying people who have specific gene pathways linked to schizophrenia could help us better tailor medications to those who will benefit most by them.

Another “Stem Cellar” Report by Kevin McCormack

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Making a good thing better

by Kevin McCormack

Thomas Edison

Legend has it that Thomas Edison “failed” 1,000 times before he managed to create the incandescent lightbulb. Edison says he didn’t get discouraged, instead he looked at each unsuccessful experiment as being one step closer to finding the method that really worked. That’s a lesson in optimism and persistence for all of us.

Lineage Cell Therapeutics has that same spirit. Lineage is trying to develop a stem cell therapy to help people with spinal cord injuries. CIRM invested $14.3 million in the first version of this approach which produced encouraging results. But encouraging is not enough. So, Lineage set about doing a complete overhaul of the therapy known as OPC1.

The idea behind it is to turn embryonic stem cells into oligodendrocyte progenitor cells (OPCs). These OPCs are precursors to cells that play an important role in supporting and protecting nerve cells in the central nervous system, the area damaged in a spinal cord injury. By transplanting these cells at the injury site it’s hoped they will help restore some of the broken connections, allowing patients to regain some movement and feeling.

In the original trial many patients, who had been paralyzed from the chest down, regained some use of their arms, hands and even fingers. This was better than any previous therapy had managed. But for Lineage it wasn’t good enough. So, they set about redesigning their whole manufacturing process, making improvements at every step along the way.

In a news release they outlined those improvements:

  • A new ready-to-inject formulation of OPC1, which enables clinical use at a much larger number of spinal cord treatment centers, accelerating enrollment for a larger and potentially registrational clinical trial.
  • Elimination of dose preparation, reducing overall preparation time from 24 hours to 30 minutes and cutting logistics costs by approximately 90%.
  • A 10 to 20-fold increase in OPC1 production scale, sufficient to support late-stage clinical development and which can be further scaled to meet initial commercial use.
  • A 50-75% reduction in product impurities.
  • Improvements in OPC1 functional activity, as assessed by cellular migration and secretion of key growth factors.

They also came up with new quality control tests to make sure everything was working well and eliminated all animal-based production reagents.

Brian Culley, Lineage CEO was, understandably, enthusiastic about the changes and its prospects for helping people with spinal cord injuries:

“Manufacturing is the foundation of cell therapy and the significant enhancements we have achieved with OPC1 marks the second time we have successfully transformed a research-grade production process into one capable of supporting a successful commercial product. Our objective is to be the premier allogeneic cell therapy company and our dedication to manufacturing excellence allows us not only to reduce or eliminate certain regulatory and commercial hurdles, but also establish strong competitive barriers in our field.”

Lineage are now hoping to go back to the Food and Drug Administration (FDA) in the near future and get permission to run another clinical trial.

Here are stories of the impact the first generation of this approach have already had on people.

Your Science Donation Dollars at Work….

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UCLA scientists discover how SARS-CoV-2 causes multiple organ failure in mice

by Yimy Villa

Heart muscle cells in an uninfected mouse (left) and a mouse infected with SARS-CoV-2 (right) with mitochondria seen in pink. The disorganization of the cells and mitochondria in the image at right is associated with irregular heartbeat and death.
Image credit: UCLA Broad Stem Cell Center

As the worldwide coronavirus pandemic rages on, scientists are trying to better understand SARS-CoV-2, the virus that causes COVID-19, and the effects that it may have beyond those most commonly observed in the lungs. A CIRM-funded project at UCLA, co-led by Vaithilingaraja Arumugaswami, Ph.D. and Arjun Deb, M.D. discovered that SARS-CoV-2 can organ failure in the heart, kidney, spleen, and other vital organs of mice.

Mouse models are used to better understand the effects that a disease can have on humans. SARS-CoV-2 relies on a protein named ACE2 to infect humans. However, the virus doesn’t recognize the mouse version of the ACE2 protein, so healthy mice exposed to the SARS-CoV-2 virus don’t get sick.

To address this, past experiments by other research teams have genetically engineered mice to have the human version of the ACE2 protein in their lungs. These teams then infected the mice, through the nose, with the SARS-CoV-2 virus. Although this process led to viral infection in the mice and caused pneumonia, they don’t get as broad a range of other symptoms as humans do.

Previous research in humans has suggested that SARS-CoV-2 can circulate through the bloodstream to reach multiple organs. To evaluate this further, the UCLA researchers genetically engineered mice to have the human version of the ACE2 protein in the heart and other vital organs. They then infected half of the mice by injecting SARS-CoV-2 into their bloodstreams and compared them to mice that were not infected. The UCLA team tracked overall health and analyzed how levels of certain genes and proteins in the mice changed.

Within seven days, all of the mice infected with the virus had stopped eating, were completely inactive, and had lost an average of about 20% of their body weight. The genetically engineered mice that had not been infected with the virus did not lose a significant amount of weight. Furthermore, the infected mice had altered levels of immune cells, swelling of the heart tissue, and deterioration of the spleen. All of these are symptoms that have been observed in people who are critically ill with COVID-19.

What’s even more surprising is that the UCLA team also found that genes that help cells generate energy were shut off in the heart, kidney, spleen and lungs of the infected mice. The study also revealed that some changes were long-lasting throughout the organs in mice with SARS-CoV-2. Not only were genes turned off in some cells, the virus made epigenetic changes, which are chemical alterations to the structure of DNA that can cause more lasting effects. This might help explain why some people that have contracted COVID-19 have symptoms for weeks or months after they no longer have traces of the virus in their body.

In a UCLA press release, Dr. Deb discusses the importance and significance of their findings.

“This mouse model is a really powerful tool for studying SARS-CoV-2 in a living system. Understanding how this virus can hijack our cells might eventually lead to new ways to prevent or treat the organ failure that can accompany COVID-19 in humans.”

The full results of this study were published in JCI Insight.