CC-101 (f/k/a NR1) Neural Stem Cell Transplantation for Adults With Chronic Ischemic Stroke (suNR1se II)

A Phase 2b, Prospective, Randomized, Multi-Center, Double-Blinded, Controlled Trial to Assess the Efficacy and Safety of Stereotactic Intracerebral Transplantation of Allogeneic Neural Stem Cells CC-101 (f/k/a NR1) in Adults With Chronic Ischemic Subcortical ± Cortical Stroke

The suNR1se II Study is a Phase 2b randomized, controlled, multi-center clinical trial evaluating the efficacy and safety of stereotactic intracerebral administration of CC-101 (f/k/a NR1), an investigational allogeneic neural stem cell therapy, in adults with chronic ischemic stroke and persistent motor impairment. The study is designed to assess whether administration of CC-101 immediately adjacent to the region of prior stroke injury may improve motor function recovery compared with a sham surgical control procedure. The study will also evaluate the role of short-term anti-rejection therapy with tacrolimus in subjects receiving CC-101. Approximately 36 participants will be randomized in a 1:1:1 ration to receive CC-101 plus tacrolimus, sham surgery (no CC-101) plus tacrolimus-matched placebo, or CC-101 plus tacrolimus-matched placebo. Participants will be followed for safety and functional outcomes for at least 12 months following the study procedure.

Study Overview

• Status: Not yet recruiting
• Conditions: Chronic Ischemic Stroke
• Intervention / Treatment: Biological: CC-101 (f/k/a NR1) Intracerebral Transplantation; Drug: Tacrolimus; Procedure: Sham Surgical Control

Detailed Description

CC-101 (f/k/a NR1) is an investigational allogeneic neural stem cell therapy being developed to support endogenous repair and regenerative mechanisms within the brain following ischemic injury and infarction (i.e., ischemic stroke). Rather than directly replacing stroke-damaged and dead brain cells and tissue, CC-101 is intended to promote recovery through local production of biologically active factors that support neurogenesis (i.e., new brain cell production), angiogenesis (i.e., new blood vessel formation), plasticity (i.e., rewiring of synaptic connections), extracellular matrix remodeling (i.e., change materials around brain cells), and modulation of inflammation. The suNR1se II Study is a prospective, randomized, controlled Phase 2b study designed to evaluate the efficacy and safety of stereotactic intracerebral administration of CC-101 in adults with chronic ischemic subcortical ischemic stroke, with or without adjacent cortical involvement. Participants will be randomized equally to one of three study arms: 1) CC-101 plus tacrolimus (Experimental Arm A), 2) sham surgery plus placebo (Control Arm B), or 3) CC-101 plus placebo (Exploratory Arm C). The inclusion of sham surgery control (Arm B) and tacrolimus-matched placebo anti-rejection therapy (Arms B & C) is intended to support rigorous evaluation of CC-101 treatment effect and further characterization of the role of tacrolimus in allogeneic neural stem cell therapy for chronic ischemic stroke. The primary efficacy assessment will evaluate changes in arm and leg motor functions between baseline and 12 months following intervention. Safety assessments will include adverse events, serious adverse events, neurosurgical complications, imaging findings, laboratory assessments, hospitalization events, and mortality.

• Study Type: Interventional
• Enrollment (Estimated): 36
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Ruth Antoine, MS, MBA; Phone Number: 732-551-6611; Email: rantoine@clarioncells.com
• Study Contact Backup: Name: Steven R Deitcher, MD; Email: srdeitcher@clarioncells.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

KEY INCLUSION CRITERIA:

1. Confirmed diagnosis of completed ischemic subcortical stroke in the middle cerebral artery (MCA) distribution with or without cortical involvement based on magnetic resonance imaging (MRI) and/or computed tomography (CT) scan(s).
2. Index stroke occurred ≥ 6 months and ≤ 84 months prior to providing informed consent.
3. Age ≥ 18 years and ≤ 75 years at the time of providing informed consent.
4. Chronic motor neurological deficit due to the index stroke.
5. Total Fugl-Meyer Motor Scale (FMMS) > 25 and ≤ 75 at baseline.
6. Modified Rankin Score (mRS) of 2-4 at baseline.
7. Subjects taking oral anti-spasticity agent (such as tizanidine hydrochloride or baclofen) must be on a stable dose for 90 days prior to a Screening/Baseline visit.

KEY EXCLUSION CRITERIA:

1. Stroke lesion <1 cm3 or >100 cm3 as measured by MRI.
2. Previous history of symptomatic stroke(s) with incomplete motor recovery (NOT including index stroke).
3. Complete or near complete lack of right and/or left upper extremity and/or right and/or left lower extremity movement as defined by the MRC Scale for Muscle Strength scores.
4. History of any neuromuscular, rheumatologic, autoimmune, orthopedic, or other disease or condition that limits motor function.
5. Acute myocardial infarction (heart attack), acute pulmonary embolism (blood clot to the lungs), acute proximal deep vein thrombosis (blood clot in the leg or arm), acute peripheral arterial occlusion, or any other type of acute blood clotting episode within six (6) months of study screening.
6. Intracoronary and/or other intra-arterial stent placement within 12 months of study Screening/Baseline visits requiring uninterrupted anticoagulant and/or anti-platelet therapy.
7. Contracture involving a shoulder, elbow, wrist, finger, hip, knee, and/or ankle.
8. Any contraindication to stereotactic brain surgery.
9. Presence of serum anti-Human Leukocyte Antigen (HLA) Class I and/or Class II antibodies to donor NR1 cells with a Luminex assay value greater than the larger of the central lab's reference ULN or 3,000 Maximum Fluorescence Intensity.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: CC-101 (f/k/a NR1) + oral Tacrolimus [ARM A]; Participants will receive stereotactic intracerebral administration of investigational CC-101 allogeneic neural stem cells on Day 0 plus twice-daily oral tacrolimus anti-rejection therapy from Day -2 to Day +60.	Biological: CC-101 (f/k/a NR1) Intracerebral Transplantation; Investigational allogeneic neural stem cell product administered stereotactically via intracerebral injection immediately adjacent to the prior stroke lesion.; Drug: Tacrolimus; Oral tacrolimus or tacrolimus-matched placebo initiated prior to study intervention and continued for approximately 60 days following study intervention per protocol-defined dosing and taper schedule.
Sham Comparator: Partial thickness burr hole without any cells + oral Tacrolimus-matched placebo [ARM B]; Participants will undergo a sham surgical control procedure on Day 0 designed to preserve study blinding along with twice-daily oral tacrolimus-matched placebo from Day -2 to Day +60.	Procedure: Sham Surgical Control; Participants will undergo a partial thickness burr hole craniotomy without disruption of the meninges or transplantation of any cells as a means to maintain treatment masking.
Experimental: CC-101 (f/k/a NR1) + oral Tacrolimus-matched placebo [ARM C]; Participants will receive stereotactic intracerebral administration of investigational CC-101 allogeneic neural stem cells on Day 0 plus twice-daily oral tacrolimus-matched placebo therapy from Day -2 to Day +60.	Biological: CC-101 (f/k/a NR1) Intracerebral Transplantation; Investigational allogeneic neural stem cell product administered stereotactically via intracerebral injection immediately adjacent to the prior stroke lesion.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total Fugl-Meyer Motor Scale (FMMS) Score on Day +365 Following Neurosurgical Intervention (CC-101 transplantation or sham surgery) on Day 0.	The total Fugl-Meyer Motor Scale (FMMS) score (0-100; the larger the better) reflects the sum of the upper extremity (0-66) and lower extremity (0-34) FMMS scores. For each study subject, this clinical assessment of motor function on Day +365 will be compared with the baseline total FMMS score to determine the interval change in motor function.	Baseline to Day +365.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total Fugl-Meyer Motor Scale (FMMS) Score on Day +365 Following Neurosurgical Intervention (CC-101 transplantation or sham surgery) on Day 0.	Each study subject will be categorized as having an increase in total FMMS score of ≥10 points or an increase of <10 points (including unchanged scores and decreased scores) between baseline assessment and assessment on Day +365 following neurosurgical intervention.	Baseline to Day +365.
Total Fugl-Meyer Motor Scale (FMMS) Score on Day +90 and Day +182 Following Neurosurgical Intervention (CC-101 transplantation or sham surgery) on Day 0.	For each study subject, this clinical assessment of motor function on Day +90 and Day +182 will be compared with the baseline total FMMS score to determine the interval change in motor function.	Baseline to Day +90 and baseline to Day +182
Total Fugl-Meyer Motor Scale (FMMS) Score on Day +90 and Day +182 Following Neurosurgical Intervention (CC-101 transplantation or sham surgery) on Day 0.	Each study subject will be categorized as having an increase in total FMMS score of ≥10 points or an increase of <10 points (including unchanged scores and decreased scores) between baseline assessment and assessments on Day +90 and on Day +182 following neurosurgical intervention.	Baseline to Day +90 and baseline to Day +182.
Upper Extremity Motor Function as Assessed by the Action Research Arm Test (ARAT) on Day +365 Following Neurosurgical Intervention (CC-101 transplantation or sham surgery) on Day 0.	Each study subject will be categorized as having an increase in ARAT score of ≥5.7 points or an increase of <5.7 points (including unchanged scores and decreased scores) between baseline assessment and assessment on Day +365 following neurosurgical intervention.	Baseline to Day +365.
Barthel Index on Day +90 and Day +182 Following Neurosurgical Intervention (CC-101 transplantation or sham surgery) on Day 0.	For each study subject, this clinical assessment of functional independence on Day +90 and Day +182 will be compared with the baseline Barthel Index to determine the interval change.	Baseline to Day +90 and baseline to Day +182.
Gait Velocity Using the Comfortable Gait Speed Test Measuring 10 Meters of Timed Gait Speed on Day +365 Following Neurosurgical Intervention (CC-101 transplantation or sham surgery) on Day 0..	Each study subject will be categorized as having or not having an improvement in gait function by at least one functional level using the 10-meter walk test between baseline assessment and assessment on Day +365 following neurosurgical intervention.	Baseline to Day +365.
Overall Survival on Day +90, Day +182, and Day +365 Following Neurosurgical Intervention (CC-101 transplantation or sham surgery) on Day 0.	Subject survival to key assessment milestones will be assessed. Time to all-cause subject death following study Day 0 neurosurgery will be estimated using the product-limit (Kaplan-Meier) method.	Survival rates at Day +90, Day +182, and Day +365.

Collaborators and Investigators

• Sponsor: Clarion Cells, Inc.
• Investigators: Study Chair: Gary K Steinberg, MD, PhD, Stanford University School of Medicine, Department of Neurosurgery

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2027
• Primary Completion (Estimated): January 1, 2029
• Study Completion (Estimated): January 1, 2029

Study Registration Dates

• First Submitted: July 12, 2026
• First Submitted That Met QC Criteria: July 12, 2026
• First Posted (Actual): July 17, 2026

Study Record Updates

• Last Update Posted (Actual): July 17, 2026
• Last Update Submitted That Met QC Criteria: July 12, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Cell Therapy; Stroke; Ischemic Stroke; Allogeneic Cell Therapy; Chronic Stroke; Stroke Rehabilitation; Neuroregeneration; Motor Recovery; Regenerative Medicine; Neural Stem Cells; Intracerebral Transplantation; Stroke Impairment; Stroke Mobility Impairment
• Additional Relevant MeSH Terms: Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Ischemic Stroke; Stroke; Organic Chemicals; Macrolides; Lactones; Tacrolimus
• Other Study ID Numbers: NR1-03

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No