A Study to Evaluate the Safety and Efficacy of SCTC21C in Combination With Bortezomib, Cyclophosphamide, and Dexamethasone in Patients With Newly Diagnosed Systemic Light-Chain Amyloidosis (NDSLCA)

A Phase 3 Randomized, Open-label, Multicenter Study to Evaluate the Safety and Efficacy of SCTC21C in Combination With Bortezomib, Cyclophosphamide, and Dexamethasone Versus Bortezomib, Cyclophosphamide, and Dexamethasone in Patients With Newly Diagnosed Systemic Light-Chain Amyloidosis

The purpose of this study is to evaluate the efficacy and safety of SCTC21C plus cyclophosphamide, bortezomib and dexamethasone (VCd) compared with VCd alone in treatment of newly diagnosed amyloid light chain (AL) amyloidosis participants.

Study Overview

• Status: Recruiting
• Conditions: Amyloidosis
• Intervention / Treatment: Drug: SCTC21C; Drug: Bortezomib; Drug: Dexamethasone; Drug: Cyclophosphamide

Detailed Description

This study comprises two phases: Part 1 is the safety run in, while Part 2 is a randomized, controlled, open-label, multicenter study. Both parts are divided into three stages: the screening period (up to 28 days before first dose/randomization), the treatment period (from Cycle 1 [28 days] Day 1 and continues until disease progression or unacceptable toxicity), and the follow-up period (Postintervention). Safety endpoints include treatment-emergent adverse events , treatment-related adverse events, serious adverse events, clinical laboratory tests, vital signs, physical examinations, electrocardiograms , etc. Efficacy endpoints include Overall Complete Hematologic Response (CHR)，objective response rate (ORR), Hematologic Very Good Partial Response (VGPR) or Better Rate, Overall Survival (OS).

• Study Type: Interventional
• Enrollment (Estimated): 90
• Phase: Phase 3

Contacts and Locations

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China, 100000
      • Recruiting
      • Peking Union Medical College Hospital
      • Contact: Yazhou Zhao; Phone Number: 13001958778; Email: yuhuan_jiao@sinocelltech.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Histopathological diagnosis of amyloidosis based on detection by immunohistochemistry and polarizing light microscopy of green bi-refringent material in congo red stained tissue specimens or characteristic electron microscopy appearance;
• Measurable disease of amyloid light-chain (AL) amyloidosis;
• One or more organs impacted by AL amyloidosis according to consensus guidelines
• Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) 0, 1 or 2

Exclusion Criteria:

• Prior therapy for AL amyloidosis;
• Other amyloidosis;
• Uncontrolled infection.
• Subjects with conditions that may affect safety or efficacy assessments include, but are not limited to, cardiovascular, respiratory, endocrine/metabolic, immune system, hepatic, gastrointestinal (such as gastrointestinal bleeding, perforation, ulcers, etc.), and malignant neoplasms, and are deemed clinically significant by the investigator.
• Subjects who have undergone major surgery or experienced significant trauma within 4 weeks prior to the first use of the investigational drug, or who require elective surgery during the trial period.
• Received a live or attenuated vaccine within 30 days prior to the first dose; Female subjects who are currently breastfeeding.
• Subjects with mental disorders or poor compliance, or other circumstances deemed unsuitable for participation in this study by other investigators.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: SCTC21C + VCd (S-VCd)	Drug: SCTC21C; Pharmaceutical form: Solution for infusion； Route of administration: Subcutaneous; Drug: Bortezomib; Pharmaceutical form: Lyophilized powder for injection； Route of administration: Subcutaneous; Drug: Dexamethasone; Pharmaceutical form: Tablets, ampoules or vials for injection； Route of administration: Oral/Intravenous; Drug: Cyclophosphamide; Pharmaceutical form: Tablets, ampoules or vials for injection； Route of administration: Oral/Intravenous
Active Comparator: VCd	Drug: Bortezomib; Pharmaceutical form: Lyophilized powder for injection； Route of administration: Subcutaneous; Drug: Dexamethasone; Pharmaceutical form: Tablets, ampoules or vials for injection； Route of administration: Oral/Intravenous; Drug: Cyclophosphamide; Pharmaceutical form: Tablets, ampoules or vials for injection； Route of administration: Oral/Intravenous

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of Participants With Overall Complete Hematologic Response (CHR)	Overall CHR rate was defined as percentage of participants who achieved CHR, according to the International Amyloidosis Consensus Criteria.	Up to approximately 50 months after the First Participant In (FPI)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Major Organ Deterioration Progression-Free Survival (MOD-PFS)	MOD-PFS was defined as duration from the date of randomization to either hematologic progression, or major organ deterioration (clinical manifestation of cardiac failure or renal failure), or death, whichever occurred first.	Up to approximately 50 months after the FPI
Percentage of Participants Who Achieved Complete Hematologic Response (CHR) at 6 Months	CHR rate was defined as percentage of participants who achieved CHR, according to the International Amyloidosis Consensus Criteria.	Month 6
Duration of Complete Hematologic Response (CHR)	Duration of CHR was defined as the time between the date of initial documentation of CHR to the date of first documented evidence of hematologic progressive diseased.	Up to approximately 50 months after the FPI
Hematologic Very Good Partial Response (VGPR) or Better Rate	Hematologic VGPR or Better Rate was defined as percentage of participants who achieved hematologic Complete response (CR) or VGPR.	Up to approximately 50 months after the FPI
Overall Survival (OS)	Overall survival (OS) was measured from the date of randomization to the date of the participant's death.	Up to approximately 50 months after the FPI
Adverse Events	Treatment-emergent adverse events/serious adverse events	Up to approximately 50 months after the FPI

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
PRO: EQ-5D-5L	Health state utility and health status will be assessed using the European Quality of Life Group questionnaire with 5 dimensions and 5 levels per dimension (EQ-5D-5L)	Up to approximately 50 months after the FPI

Collaborators and Investigators

• Sponsor: Sinocelltech Ltd.

Study record dates

Study Major Dates

• Study Start (Actual): January 8, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2028

Study Registration Dates

• First Submitted: January 28, 2026
• First Submitted That Met QC Criteria: January 28, 2026
• First Posted (Actual): February 5, 2026

Study Record Updates

• Last Update Posted (Actual): February 5, 2026
• Last Update Submitted That Met QC Criteria: January 28, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Metabolic Diseases; Proteostasis Deficiencies; Nutritional and Metabolic Diseases; Amyloidosis; Organic Chemicals; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Hydrocarbons; Polycyclic Compounds; Inorganic Chemicals; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Steroids, Fluorinated; Phosphoramide Mustards; Nitrogen Mustard Compounds; Mustard Compounds; Hydrocarbons, Halogenated; Phosphoramides; Organophosphorus Compounds; Pregnadienetriols; Boronic Acids; Acids, Noncarboxylic; Acids; Boron Compounds; Pyrazines; Bortezomib; Dexamethasone; Cyclophosphamide
• Other Study ID Numbers: SCTC21C-B301

Drug and device information, study documents

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