Apoptotic Cells for Therapeutic Use in Cytokine Storm Associated With Sepsis- A Phase Ib Clinical Trial

Abstract

Background: Sepsis has no proven specific pharmacologic treatment and reported mortality ranges from 30%-45%. The primary aim of this phase IB study was to determine the safety profile of Allocetra™-OTS (early apoptotic cell) infusion in subjects presenting to the emergency room with sepsis. The secondary aims were to measure organ dysfunction, intensive care unit (ICU) and hospital stays, and mortality. Exploratory endpoints included measuring immune modulator agents to elucidate the mechanism of action.

Methods: Ten patients presenting to the emergency room at the Hadassah Medical Center with sepsis were enrolled in this phase Ib clinical study. Enrolled patients were males and females aged 51-83 years, who had a Sequential Organ Failure Assessment (SOFA) score ≥2 above baseline and were septic due to presumed infection. Allocetra™-OTS was administered as a single dose (day +1) or in two doses of 140×106 cells/kg on (day +1 and +3), following initiation of standard-of-care (SOC) treatment for septic patients. Safety was evaluated by serious adverse events (SAEs) and adverse events (AEs). Organ dysfunction, ICU and hospital stays, and mortality, were compared to historical controls. Immune modulator agents were measured using Luminex® multiplex analysis.

Results: All 10 patients had mild-to-moderate sepsis with SOFA scores ranging from 2-6 upon entering the study. No SAEs and no related AEs were reported. All 10 study subjects survived, while matched historical controls had a mortality rate of 27%. The study subjects exhibited rapid resolution of organ dysfunction and had significantly shorter ICU stays compared to matched historical controls (p<0.0001). All patients had both elevated pro- and anti-inflammatory cytokines, chemokines, and additional immune modulators that gradually decreased following treatment.

Conclusion: Administration of apoptotic cells to patients with mild-to-moderate sepsis was safe and had a significant immuno-modulating effect, leading to early resolution of the cytokine storm.

Clinical trial registration: ClinicalTrials.gov Identifier: NCT03925857. (https://ichgcp.net/clinical-trials-registry/NCT03925857).

Keywords: Inflammation; apoptotic cells; cell therapeutics; cytokine storm; pneumonia; sepsis.

Conflict of interest statement

PvH received honoraria from Enlivex Ltd as a consultant. DM is the founder, and CMO of Enlivex Therapeutics Ltd. YS and BR are part of the research team of Enlivex Therapeutics Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest.

Copyright © 2021 van Heerden, Abutbul, Sviri, Zlotnick, Nama, Zimro, el-Amore, Shabat, Reicher, Falah and Mevorach.

Figures

Figure 1

Acute phase markers. Complete blood count (CBC) and C-reactive protein (CRP). Blood counts of fresh peripheral patient blood ethylenediamine tetraacetic acid (EDTA) samples were performed using blood analyzer. The differential of white blood cells (WBC), i.e. WBC subpopulations, was calculated. ‘Screening’ is a time point with a blood count that was performed 24 ± 6h before treatment with Allocetra-OTS, to test for the patient’s eligibility for Allocetra-OTS treatment. ‘Day 1’ is a blood sample just prior to Allocetra-OTS infusion. Numbers (109 cells/L) of (A) WBCs, (B) neutrophils, and (C) lymphocytes, are shown. (D) CRP levels of all patients in the indicated time points. *Patients 09–12 received two doses of Allocetra-OTS (days 1 and 3).

Figure 2

Kaplan-Meier survival curve. A comparison of survival between the study group (n=10) and matched-historical controls from the same hospital (n=37) for (A) all patients, and (B) patients with pneumonia (n=5 for the study group, n=19 for the historical controls), is shown. Matched controls were selected from all patients admitted to ICU with a diagnosis of sepsis between 2014–2019 and were matched by gender, age ± 7, Sequential Organ Failure Assessment (SOFA) score ±2 at presentation, and source of infection.

Figure 3

SOFA score progression during sepsis. (A) SOFA score at presentation compared to maximal SOFA score. (B–D) Change in SOFA score before administration of Allocetra-OTS and day 5 (B), day 7 (C), and day 28 (D). Average delta area under the curve (AUC) in the first (E) five days, and (F) seven days. Matched controls were selected from all patients admitted to ICU under the diagnosis of sepsis between 2014–2019 and were matched by gender, age ±7 years, SOFA score ±2 at presentation, and source of infection. Data is presented as the median within the interquartile range (IQR); mean values are marked with a ‘+’ sign; error bars represent the 10-90 percentile, with outliers presented.

Figure 4

Hospital and ICU/IMU duration of stay. The duration of stay for all patients in the study and for all patients in the matched historical control group who survived is presented (A) in the hospital and (B) in the Intensive Care Unit (ICU) or the Intermediate Medical Unit (IMU). Kaplan-Meier curves describing time-to-discharge from the (C) hospital and (D) ICU/IMU are presented. Matched controls were selected from all patients admitted to ICU/IMU with the diagnosis of sepsis between 2014–2019 and were matched by gender, age ±7, SOFA score ±2 at presentation, and source of infection. Data is presented as the median within the interquartile range (IQR); mean values are marked with a ‘+’ sign; error bars represent the 10–90 percentile, with outliers presented.

Figure 5

Pro-inflammatory cytokine kinetics during sepsis. Serum was obtained from patients at the indicated times and cytokine analysis was performed as described in Methods. The serum of three healthy volunteers was analyzed using the same methods and values are presented as the normal range (median ± range). Serum concentrations of (A) IL-6, (B) TNF-α, (C) IL-1β, (D) IL-18, and (E) IFN-γ are presented. Patients 01–08 received one dose of Allocetra-OTS on day 1 and patients 09–12 received two doses on days 1 and 3.

Figure 6

Anti-Inflammatory cytokine and growth factor kinetics during sepsis. Serum was obtained from patients at the indicated times and cytokine/growth factor analysis was performed as described in Methods. The serum of three healthy volunteers was analyzed using the same methods and values are presented as the normal range (median ± range). Serum concentrations of (A) IL-10, (B) IL-1Ra, (C) TNFR-1 are presented in the upper panel, (D) G-CSF, (E) VEGF, and (F) GM-CSF are presented in the lower panel. Patients 01–08 received one dose of Allocetra-OTS on day 1 and patients 09–12 received two doses on days 1 and 3.

Figure 7

Chemokine kinetics during sepsis. Serum was obtained from patients at the indicated times and cytokine/growth factor analysis was performed as described in Methods. The serum of three healthy volunteers was analyzed using the same methods and values are presented as the normal range (median ± range). Serum concentrations of (A) MCP-1, (B) IP-10, (C) MIP-1α, (D) IL-8, (E) GRO-β, and (F) RANTES are presented. Patients 01–08 received one dose of Allocetra-OTS on day 1 and patients 09–12 received two doses on days 1 and 3.

Figure 8

Immune modulator and endocrine hormone kinetics during sepsis. Serum was obtained from patients at the indicated times and cytokine/growth factors analysis was performed as described in Methods. The serum of three healthy volunteers was analyzed using the same methods and values presented as the normal range (median ± range). Serum concentrations of (A) TREM-1, (B) osteopontin, (C) N-GAL, (D) ghrelin, (E) leptin, and (F) glucagon, (G) cortisol, and (H) FT3 are presented in the lower panel. Patients 01–08 received one dose of Allocetra-OTS on day 1 and patients 09–12 received two doses on days 1 and 3.

Figure 9

Correlation matrix of cytokines, chemokines, and immunomodulators with SOFA score, CRP, and blood counts. A correlation heat-map of the tested cytokines/chemokines, HGFs, and immunomodulators with CRP, SOFA score, and blood counts. Pearson’s r values are on the top right and the Spearman’s ρ values are on the bottom left.