A First-in-human Study of KT501 Administered Subcutaneously to Patients With Rheumatoid Arthritis (RA).

NCT ID: NCT07234773

Last Updated: 2025-11-18

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Clinical Phase: PHASE1
• Total Enrollment: 14 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-12-15
• Study Completion Date: 2027-08-31

Brief Summary

This is a Phase 1, open-label, first-in-human study to investigate the safety, tolerability, pharmacokinetics and pharmacodynamics of KT501 administered subcutaneously to participants with Rheumatoid Arthritis (RA).

Detailed Description

This is a Phase 1, open-label, first-in-human dose escalation study to investigate the safety, tolerability, pharmacokinetic and pharmacodynamic of KT501 by a single subcutaneous administration in participants with Rheumatoid Arthritis (RA).

Up to a total of 5 cohorts with up to approximately 14 participants in total with RA will be enrolled. All will receive a single dose of KT501 on Day 1 and followed up until Week 12. For any participants with B cells lower than baseline level or lower limit quantification, whichever is lower, additional B cell follow up is required up to 6 months after the study treatment.

Conditions

Rheumatoid Arthritis (RA)

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: SEQUENTIAL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Dose Level 1

KT501 Subcutaneous Injection Dose Level 1

Group Type: EXPERIMENTAL

KT501

Intervention Type: DRUG

KT501 is a monoclonal antibody that depletes B cells including plasma cells by targeting CD19, BCMA and CD3.

Dose Level 2

KT501 Subcutaneous Injection Dose Level 2

Group Type: EXPERIMENTAL

KT501

Intervention Type: DRUG

KT501 is a monoclonal antibody that depletes B cells including plasma cells by targeting CD19, BCMA and CD3.

Dose Level 3

KT501 Subcutaneous Injection Dose Level 3

Group Type: EXPERIMENTAL

KT501

Intervention Type: DRUG

KT501 is a monoclonal antibody that depletes B cells including plasma cells by targeting CD19, BCMA and CD3.

Dose Level 4

KT501 Subcutaneous Injection Dose Level 4

Group Type: EXPERIMENTAL

KT501

Intervention Type: DRUG

KT501 is a monoclonal antibody that depletes B cells including plasma cells by targeting CD19, BCMA and CD3.

Dose Level 5

KT501 Subcutaneous Injection Dose Level 5

Group Type: EXPERIMENTAL

KT501

Intervention Type: DRUG

KT501 is a monoclonal antibody that depletes B cells including plasma cells by targeting CD19, BCMA and CD3.

Interventions

KT501

KT501 is a monoclonal antibody that depletes B cells including plasma cells by targeting CD19, BCMA and CD3.

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

1. 18 to 75 years old

2. Diagnosis of adult-onset RA for at least 6 months

3. Moderately to severely active RA

4. Inadequate treatment response as defined in the protocol

5. RF + or ACPA+

6. Stable use of traditional DMARDs is permitted

7. Willing and able to comply with all study assessments and adhere to the protocol schedule and restrictions.

Exclusion Criteria

1. Functional class IV as defined by the ACR Classification of Functional Status in RA

2. Presence of any concomitant autoimmune disease other than RA

3. Active infection, history of serious recurrent or chronic infection

4. History of progressive multifocal leukoencephalopathy

5. Have a diagnosis or history of malignant disease within 5 years or breast cancer diagnosed within the previous 10 years.

6. History of or planned organ transplant and/or autologous or allogeneic hematopoietic stem cell transplantation

7. Receipt of live vaccine within 4 weeks

8. Major surgery (including joint surgery) within 8 weeks prior to screening or planned major surgery within 6 months after study

9. Women who are pregnant or breastfeeding

10. Significant or uncontrolled medical disease that would preclude participant participation

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 75 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Kali Therapeutics, Inc.

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Central Contacts

Trial Information

Role: CONTACT

clinical@kalitherapeutics.com

1-858-888-3080

Other Identifiers

KT501-001

Identifier Type: -

Identifier Source: org_study_id