Purpose

The purpose of this Phase 3 study is to demonstrate the efficacy, safety, and tolerability of claseprubart in participants with generalized myasthenia gravis (gMG).

Condition

Eligibility

Eligible Ages
Between 18 Years and 80 Years
Eligible Sex
All
Accepts Healthy Volunteers
No

Inclusion Criteria

  1. Must have given written informed consent before any study-related activities are carried out 2. Weight range between 40-130 kg at Screening 3. Diagnosis of gMG by the following tests: 1. Acetylcholine receptor antibody (AChR Ab) positive, and 2. One of the following: i. History of abnormal neuromuscular transmission test; ii. History of positive anticholinesterase test; iii. Clinical response to acetylcholinesterase inhibitors. 4. Myasthenia Gravis Foundation of America (MGFA) Class II-IVa 5. MG-ADL scale score of 6 or more 6. QMG scale score of 10 or more 7. Documented vaccinations against encapsulated bacteria in accordance with local requirements and based on vaccine availability 8. Female participants must be of non-childbearing potential, or if of childbearing potential, must agree not to donate ova, not to attempt to become pregnant and, if engaging in sexual intercourse with a male partner, must agree to use a highly effective method of contraception 9. Male participants agree not to donate sperm and, if engaging in sexual intercourse with a female partner who could become pregnant, must agree to use an acceptable method of contraception

Exclusion Criteria

  1. History or presence of significant medical/surgical condition including any acute illness, mental illness, or major surgery considered to be clinically significant or that could have potential impact on safety/efficacy or study procedures 2. Known complement deficiency 3. Prior history (at any time) of N. meningitidis infection 4. Participants with known seropositivity or who test positive for an active viral infection with human immunodeficiency virus (HIV-1 or HIV-2), hepatitis B (HBV; except participants who are seropositive because of HBV vaccination) or hepatitis C virus (HCV) during Screening 5. Previous treatment with claseprubart (DNTH103) or participation in a clinical trial with claseprubart. [ 6. Any thymic surgery/biopsy within 1 year of Screening 7. Any known or untreated thymoma. 8. Any history of thymic carcinoma or thymic malignancy 9. History of active malignancy within 5 years prior to Screening, except basal cell carcinoma of the skin, curatively resected squamous cell carcinoma of the skin, cervical carcinoma in situ curatively treated or low-grade prostate adenocarcinoma for which appropriate management is observation alone 10. Concurrent or previous use of the following medication within the time periods specified below. 1. Rituximab or other B-cell targeting therapies (ie, inebilizumab) within 6 months (180 days) prior to randomization (Day 1); 2. Intravenous immunoglobulin (IVIg) and plasma exchange (PLEX) within 4 weeks (28 days) prior to randomization (Day 1) 11. Participation in another clinical study of an investigational drug within 90 days or 5 half-lives of the investigational agent 12. Diagnosis of systemic lupus erythematosus (SLE) or family history (defined as a parent, sibling, or child) of SLE

Study Design

Phase
Phase 3
Study Type
Interventional
Allocation
Randomized
Intervention Model
Parallel Assignment
Primary Purpose
Treatment
Masking
Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)

Arm Groups

ArmDescriptionAssigned Intervention
Placebo Comparator
Placebo
Intravenous (IV) infusion of Placebo on Day 1 followed by subcutaneous (SC) injections of Placebo every 2 weeks (Q2W) starting at Week 1 (Day 8).
  • Drug: Placebo
    IV infusion on Day 1
  • Combination Product: Placebo
    Prefilled syringe containing placebo for SC administration
Experimental
Claseprubart Q2W
IV loading dose of claseprubart on Day 1 followed by SC injections of claseprubart Q2W starting at Week 1 (Day 8).
  • Drug: Claseprubart
    IV loading dose on Day 1
    Other names:
    • DNTH103
  • Combination Product: Claseprubart
    Prefilled syringe containing claseprubart for SC administration
Experimental
Claseprubart Every 4 weeks (Q4W)
IV loading dose of claseprubart on Day 1 followed by SC injections of claseprubart or Placebo Q2W starting at Week 1 (Day 8), with doses alternating between claseprubart and placebo.
  • Drug: Claseprubart
    IV loading dose on Day 1
    Other names:
    • DNTH103
  • Combination Product: Claseprubart
    Prefilled syringe containing claseprubart for SC administration
  • Combination Product: Placebo
    Prefilled syringe containing placebo for SC administration

Recruiting Locations

Cinical Study Site
Fayetteville, North Carolina 28304

More Details

Status
Recruiting
Sponsor
Dianthus Therapeutics

Study Contact

Dianthus Clinical Contact Center
929-999-4055
clinicaltrials@dianthustx.com

Detailed Description

The study includes the following periods: - Screening (up to 12 weeks) - Randomized, blinded, controlled treatment (RCT) period (17 weeks) - Extended treatment period (ETP) (104 weeks) (optional) for eligible participants [includes blinded extension period (BEP) and open-label extension (OLE) period] - Safety Follow-Up period (40 weeks)

Notice

Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.