Skip to main content
OpenTrials
Recruiting

NCT Number: NCT07363590

A Clinical Study of MK-1045 in People With Lupus or Rheumatoid Arthritis (MK-1045-004)

This study looks at a study medicine called MK-1045 in people with lupus and rheumatoid arthritis (RA). The main goal of the study is to learn about the safety of MK-1045 and if people tolerate it when they receive it at different dose levels (amounts).

Recruiting

Interested in participating?

Request Info

Key information

Conditions

Systemic Lupus Erythematosus Arthritis Arthritis, Rheumatoid Autoimmune Diseases Connective Tissue Diseases Immune System Diseases Joint Diseases Lupus Erythematosus, Systemic Musculoskeletal Diseases Rheumatic Diseases Rheumatoid Arthritis Skin and Connective Tissue Diseases

Age range

18 year–75 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 1

Primary location

Gold Coast University Hospital ( Site 1601), Southport, Queensland, Australia

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Has a body mass index between 18 and 32 kg/m^2, inclusive
  • Systemic lupus erythematosus (SLE): Has a diagnosis of SLE for at least 6 months and met the European Alliance of Associations for Rheumatology (EULAR)/ American College of Rheumatology (ACR) 2019 classification criteria
  • SLE: Is taking at least one background therapy for SLE
  • RA: Has a diagnosis of RA for at least 6 months and meets the 2010 ACR-EULAR classification criteria for RA

Exclusion criteria

  • Has a known active infection (excluding fungal infection of nail beds), or any major episode of infection requiring hospitalization or treatment with anti-infectives within 8 weeks prior to the Day 1 dosing
  • History of serious recurrent or chronic infection
  • Is known to be infected with hepatitis B virus, hepatitis C virus, or human immunodeficiency virus
  • Has evidence of active tuberculosis (TB), latent TB, or inadequately treated TB
  • Has a significant or uncontrolled medical disease in any organ system not related to RA or SLE
  • For RA participants, has a history of any arthritis with onset before age 17 years
  • Has a current inflammatory condition other than SLE or RA that could interfere with disease activity assessments
  • History of cancer (except fully treated nonmelanoma skin cancers or cervical carcinoma in situ after complete surgical removal) and is disease free for <5 years before Day 1 dosing
  • Has had a major surgery within 3 months prior to Screening or has a major surgery planned during the study.
  • Has symptomatic heart failure (New York Heart Association class III or IV) or myocardial infarction or unstable angina pectoris within 6 months prior to Screening
  • Has a severe chronic pulmonary disease requiring oxygen therapy
  • Has current active lymphoproliferative disease, including lymphoma, or signs and symptoms suggestive of possible lymphoproliferative disease

Treatment and study plan

MK-1045

Biological

IV infusion

Other names: CN201

Primary outcomes

  1. Part 1: Number of Participants with One or More Adverse Events (AEs)

    Time frame: Up to approximately 12 weeks

    An AE is defined as any unfavorable and unintended sign, symptom, disease, or worsening of preexisting condition temporally associated with study treatment and irrespective of causality to study treatment.

  2. Part 1: Number of Participants who Discontinue Study Drug Due to an AE

    Time frame: Up to approximately 4 weeks

    An AE is defined as any unfavorable and unintended sign, symptom, disease, or worsening of preexisting condition temporally associated with study treatment and irrespective of causality to study treatment.

  3. Part 2 and Part 3: Number of Participants with One or More AEs

    Time frame: Up to approximately 52 weeks

    An AE is defined as any unfavorable and unintended sign, symptom, disease, or worsening of preexisting condition temporally associated with study treatment and irrespective of causality to study treatment.

  4. Part 2 and Part 3: Number of Participants who Discontinue Study Drug Due to an AE

    Time frame: Up to approximately 2 weeks

    An AE is defined as any unfavorable and unintended sign, symptom, disease, or worsening of preexisting condition temporally associated with study treatment and irrespective of causality to study treatment.

Secondary outcomes

  1. Part 1: Maximum Serum Concentration (Cmax) of MK-1045

    Time frame: At designated time points up to 12 weeks

    Blood samples will be collected to determine the Cmax, obtained directly from the measured value of the plasma concentration-time curve.

  2. Part 1: Area Under the Concentration-Time Curve from Time 0 to Infinity (AUC0-Inf) of MK-1045

    Time frame: At designated time points up to 12 weeks

    Blood samples will be collected to determine the AUC0-Inf of MK-1045.

  3. Part 1: Percentage of Participants with a Peripheral B Cell Count Less Than the Lower Limit of Quantitation (LLOQ) at the End of Each Treatment Period

    Time frame: At designated time points up to 12 weeks

    Blood samples will be collected to determine the B cell depletion in peripheral blood after treatment with MK-1045.

  4. Part 2 and Part 3: Cmax of MK-1045

    Time frame: At designated time points up to 52 weeks

    Blood samples will be collected to determine the Cmax, obtained directly from the measured value of the plasma concentration-time curve.

  5. Part 2 and Part 3: Area Under the Concentration-Time Curve From Time 0 to the End of the Dosing Interval (AUCtau) of MK-1045

    Time frame: At designated time points up to 52 weeks

    Blood samples will be collected to determine the AUCtau of MK-1045.

  6. Part 2 and Part 3: Percentage of Participants with a Peripheral B Cell Count Less Than the LLOQ at the End of the Treatment Period

    Time frame: At designated time points up to 52 weeks

    Blood samples will be collected to determine the B cell depletion in peripheral blood after treatment with MK-1045.

Study contacts

Contact information is provided by the study sponsor or research team.

Toll Free Number

CONTACT

[email protected]

1-888-577-8839

Sponsors and collaborators

Lead sponsor

Merck Sharp & Dohme LLC

Industry

Registry information

Official study title

A Dose Escalation Clinical Study to Evaluate the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of MK-1045 in Participants With Systemic Lupus Erythematosus and Rheumatoid Arthritis

Important dates

Study start
2026
Primary completion
2029
Study completion
2029
First posted
Jan 23, 2026
Registry last updated
Jul 20, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.