HyperchylomicronemiaEarly Phase 1NCT07371767
CS-121 APOC3 Base Editing in Children and Adolescents With Hyperchylomicronemia
A Early Phase 1 study testing CS-121 in people with Hyperchylomicronemia, run by Shanghai Jiao Tong University School of Medicine at 1 site in China.
Trial summary
This is a Prospective, Single-center, Open-label, Single-arm Clinical Study to Evaluate the Safety and Efficacy of CS-121, an In Vivo Base Editing Therapy Delivered by Lipid Nanoparticles Targeting APOC3, in Children and Adolescents (4-18 years) With Hyperchylomicronemia Read more about this study
- Who is it for?
- Ages 4 to 18 years
- Conditions the study is for
- Hyperchylomicronemia
- What is being tested?
- CS-121
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 15 participants
- Where
- 1 siteChina
- Study dates
- 26 Jan 2026to 31 Jan 2041
- Phase
- Early Phase 1
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 4 to 18 years
- All sexes
- No healthy volunteers
- Child, Adult
Who may be able to join
- Male or female participants aged 4 years ≤ age < 18 years.
- Severe hypertriglyceridemia (sHTG), defined as a triglyceride (TG) level ≥ 500 mg/dL.
- Confirmed diagnosis of genetically inherited FCS via genetic testing, or clinically diagnosed FCS plus persistent chylomicronemia.
- Failure to achieve adequate TG control, For participants under 8 years of age, the investigator determine at their discretion whether prior lipidlowering therapy has been administered.
- Participants aged 6 years and above must sign the informed consent form themselves; for participants under 18 years of age, their parent/legal guardian must sign the informed consent form. (Participants under 6 years of age are exempt from signing the written informed consent form).
- Female participants of childbearing potential must have a negative result on serum pregnancy testing.
Who cannot join
- Currently participating in other interventional clinical studies, or having an insufficient washout period of less than 5 half-lives or 30 days (whichever is longer) since the last administration of other investigational drugs.
- Used antisense oligonucleotide (ASO)-based or small interfering RNA (siRNA)-based lipid-lowering drugs targeting APOC3 within 3 months prior to study drug administration.
- History of acute pancreatitis within 1 month before dosing.
- Patients who underwent major surgery within 3 months prior to study drug administration and are judged by the investigator as unsuitable for receiving the study drug, due to potential intolerance to adverse events such as cytokine release storm.
- ALT or AST ≥2 × ULN
- Total bilirubin ≥1.5 × ULN
Show all 16Show fewer
- eGFR <30 mL/min/1.73 m²
- Random urine albumin-to-creatinine ratio (UACR) >30 mg/g, or urine protein is ≥ 2+
- HbA1c ≥9%
- Coagulation function abnormalities judged by the investigator as unsuitable for CS-121 administration.
- Positive results for HBsAg, dual positivity for HCV antibody and RNA, positive for HIV, or positive for Treponema pallidum infection.
- Known major organ diseases, mental disorders, Cushing's syndrome, hypothyroidism, history of lymphoproliferative disorders, or malignant tumors in any organ system, which are judged by the investigator as unsuitable for study participation due to potential intolerance to adverse events such as cytokine Release-Storm.
- Concomitant medications/treatments judged by the investigator to affect lipid metabolism, liver and kidney function, coagulation function, or interfere with the efficacy evaluation of the study drug.
- Patients of childbearing potential who are planning pregnancy, breastfeeding, or have fertility plans.
- History of hypersensitivity to any study drug, its excipients, or drugs of similar chemical classes.
- Other medical conditions or comorbidities that, in the investigator's opinion, may interfere with study compliance or data interpretation.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site, 1 recruiting
- Recruiting
Shanghai Children's Medical Center
Shanghai, Shanghai Municipality
Guoying Chang, PhD, 86+15000394881, changguoying@126.com
About this study
Official title: A Prospective, Single-center, Open-label, Single-arm Clinical Study to Evaluate the Safety and Efficacy of CS-121, an In Vivo Base Editing Therapy Delivered by Lipid Nanoparticles Targeting APOC3, in Children and Adolescents With Hyperchylomicronemia
This is a Prospective, Single-center, Open-label, Single-arm Clinical Study to Evaluate the Safety and Efficacy of CS-121, an In Vivo Base Editing Therapy Delivered by Lipid Nanoparticles Targeting APOC3, in Children and Adolescents (4-18 years) With Hyperchylomicronemia
Read the detailed description
CS-121 is an investigational, in vivo base editing therapy delivered by lipid nanoparticles (LNPs) targeting the APOC3 gene in the liver. By introducing precise base edits at specific APOC3 loci, CS-121 is intended to mimic naturally occurring protective mutations that reduce APOC3 expression, thereby restoring triglyceride clearance pathways and lowering pancreatitis risk. Preclinical studies in transgenic mouse and non-human primate models demonstrated dose-dependent APOC3 editing, reductions in serum ApoC3 protein and triglyceride levels, and acceptable safety profiles, supporting advancement into human evaluation. This open-label, single-arm, dose-escalation early exploratory trial designed to evaluate the safety, tolerability, PK/PD characteristics and preliminary efficacy of CS-121 in patients with hyperchylomicronemia. Based on the properties of gene editing therapy, the primary focus of the study is to identify the optimal biological dose (OBD) rather than the traditional maximum tolerated dose (MTD).
- Conditions
- Hyperchylomicronemia
- Being tested
- CS-121
- Keywords
- Acute Pancreatitis, Apolipoprotein C3 (APOC3), In Vivo Base Editing, Lipid Nanoparticles (LNP), Gene Editing Therapy, Children and Adolescents
- Medical subject headings
- Hyperlipoproteinemia Type I, Pancreatitis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CS-121Biological
CS-121 is a in vivo base editing therapy formulated in lipid nanoparticles for targeted editing of the APOC3 gene in hepatocytes.
| Study group | Role | What they receive |
|---|---|---|
| Low Dose CS-121 | Experimental | Participants in this arm will receive low dose of CS-121 Receives: Biological: CS-121 |
| Middle Dose CS-121 | Experimental | Participants in this arm will receive middle dose of CS-121 Receives: Biological: CS-121 |
| High Dose CS-121 | Experimental | Participants in this arm will receive high dose of CS-121 Receives: Biological: CS-121 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Dose-limiting toxicities (DLTs)
Measured: Within 14 days post CS-121 dosing
The incidence and severity of treatment-emergent adverse events (TEAEs)
Measured: from screening to 10 months post last dosing
Secondary outcomes (3)
Changes in serum triglyceride (TG) levels
Measured: From baseline to 10 months post last dosing
Changes in serum ApoC3 levels from baseline
Measured: From baseline to 10 months post last dosing
Concentrations of the active components of CS-121 (sgRNA and mRNA)
Measured: From baseline to 1 month post last dosing
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Jan 2026
- Study start26 Jan 2026 (estimated)
- Primary completion31 Oct 2027 (estimated)
- Study completion31 Jan 2041 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HyperchylomicronemiaStudies of the same condition, open and under way.
- More trials run by Shanghai Jiao Tong University School of MedicineThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Early Phase 1
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Enrolment
- 15 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Shanghai Jiao Tong University School of Medicine
- Sponsor type
- University, hospital or other
- Collaborators
- CorrectSequence Therapeutics Co., Ltd
- Responsible party
- Principal investigator, Xiumin Wang, PhD, Shanghai Jiao Tong University School of Medicine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07371767
- Sponsor's protocol ID
- CS-121-02
- Status last verified
- Jan 2026
- First submitted
- 19 Jan 2026
- Last updated
- 28 Jan 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 28 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Prospective, Single-center, Open-label, Single-arm Clinical Study to Evaluate the Safety and Efficacy of CS-121, an In Vivo Base Editing Therapy Delivered by Lipid Nanoparticles Targeting APOC3, in Children and Adolescents With Hyperchylomicronemia
- ClinicalTrials.gov ID
- NCT07371767
- Acronym / sponsor ID
- CS-121-02
- Conditions
- Hyperchylomicronemia
- Keywords
- Acute Pancreatitis, Apolipoprotein C3 (APOC3), In Vivo Base Editing, Lipid Nanoparticles (LNP), Gene Editing Therapy, Children and Adolescents
- Phase
- Early Phase 1
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 15 participants (estimated)
- Lead sponsor
- Shanghai Jiao Tong University School of MedicineUniversity, hospital or other
- Collaborators
- CorrectSequence Therapeutics Co., Ltd
- Study start
- 26 Jan 2026 (estimated)
- Primary completion
- 31 Oct 2027 (estimated)
- Study completion
- 31 Jan 2041 (estimated)
- First posted
- 28 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a Prospective, Single-center, Open-label, Single-arm Clinical Study to Evaluate the Safety and Efficacy of CS-121, an In Vivo Base Editing Therapy Delivered by Lipid Nanoparticles Targeting APOC3, in Children and Adolescents (4-18 years) With Hyperchylomicronemia
Detailed description
CS-121 is an investigational, in vivo base editing therapy delivered by lipid nanoparticles (LNPs) targeting the APOC3 gene in the liver. By introducing precise base edits at specific APOC3 loci, CS-121 is intended to mimic naturally occurring protective mutations that reduce APOC3 expression, thereby restoring triglyceride clearance pathways and lowering pancreatitis risk. Preclinical studies in transgenic mouse and non-human primate models demonstrated dose-dependent APOC3 editing, reductions in serum ApoC3 protein and triglyceride levels, and acceptable safety profiles, supporting advancement into human evaluation. This open-label, single-arm, dose-escalation early exploratory trial designed to evaluate the safety, tolerability, PK/PD characteristics and preliminary efficacy of CS-121 in patients with hyperchylomicronemia. Based on the properties of gene editing therapy, the primary focus of the study is to identify the optimal biological dose (OBD) rather than the traditional maximum tolerated dose (MTD).
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Low Dose CS-121 | Experimental | Biological: CS-121Participants in this arm will receive low dose of CS-121 |
| Middle Dose CS-121 | Experimental | Biological: CS-121Participants in this arm will receive middle dose of CS-121 |
| High Dose CS-121 | Experimental | Biological: CS-121Participants in this arm will receive high dose of CS-121 |
Who may qualify
- Ages
- 4 to 18 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult
Key inclusion criteria (6 listed)
- Male or female participants aged 4 years ≤ age < 18 years.
- Severe hypertriglyceridemia (sHTG), defined as a triglyceride (TG) level ≥ 500 mg/dL.
- Confirmed diagnosis of genetically inherited FCS via genetic testing, or clinically diagnosed FCS plus persistent chylomicronemia.
- Failure to achieve adequate TG control, For participants under 8 years of age, the investigator determine at their discretion whether prior lipidlowering therapy has been administered.
- Participants aged 6 years and above must sign the informed consent form themselves; for participants under 18 years of age, their parent/legal guardian must sign the informed consent form. (Participants under 6 years of age are exempt from signing the written informed consent form).
Key exclusion criteria (16 listed)
- Currently participating in other interventional clinical studies, or having an insufficient washout period of less than 5 half-lives or 30 days (whichever is longer) since the last administration of other investigational drugs.
- Used antisense oligonucleotide (ASO)-based or small interfering RNA (siRNA)-based lipid-lowering drugs targeting APOC3 within 3 months prior to study drug administration.
- History of acute pancreatitis within 1 month before dosing.
- Patients who underwent major surgery within 3 months prior to study drug administration and are judged by the investigator as unsuitable for receiving the study drug, due to potential intolerance to adverse events such as cytokine release storm.
- ALT or AST ≥2 × ULN
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| CS-121CS-121 is a in vivo base editing therapy formulated in lipid nanoparticles for targeted editing of the APOC3 gene in hepatocytes. | Biological | High Dose CS-121, Low Dose CS-121, Middle Dose CS-121 |
Primary outcome
Dose-limiting toxicities (DLTs)
Time frame: Within 14 days post CS-121 dosing
The incidence and severity of treatment-emergent adverse events (TEAEs)
Time frame: from screening to 10 months post last dosing
3 secondary outcomes
Changes in serum triglyceride (TG) levels
Time frame: From baseline to 10 months post last dosing
Changes in serum ApoC3 levels from baseline
Time frame: From baseline to 10 months post last dosing
Concentrations of the active components of CS-121 (sgRNA and mRNA)
Time frame: From baseline to 1 month post last dosing
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Jan 2026.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Early Phase 1 study testing CS-121 in people with Hyperchylomicronemia, run by Shanghai Jiao Tong University School of Medicine at 1 site in China.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 16 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 28 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in China. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Early Phase 1 (sometimes called Phase 0) studies give a very small amount of a treatment to a few people, mainly to see how the body handles it.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Guoying Chang, PhD (86+15000394881, changguoying@126.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Dose-limiting toxicities (DLTs) (time frame: Within 14 days post CS-121 dosing). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Jan 2026.