Cizutamig for adults with generalized myasthenia gravis

A Phase 1b, Open-Label, Multicenter Study Evaluating the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, Immunogenicity, and Preliminary Clinical Activity of Cizutamig in Patients With Generalized Myasthenia Gravis (gMG)

This will test whether cizutamig is safe and shows early benefit for adults with generalized myasthenia gravis who haven't responded to standard treatments.

Quick facts

• Phase: Phase 1
• Study type: Interventional
• Enrollment: 44 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Candid Therapeutics (Industry-sponsored)
• Drugs / interventions: rituximab, CAR-T, methotrexate
• Locations: 1 site (Shanghai, Shanghai Municipality)
• Trial ID: NCT07215650 on ClinicalTrials.gov

What this trial studies

This Phase 1b, open-label, multicenter study administers cizutamig to adults with generalized myasthenia gravis who have had inadequate responses to standard therapies. The trial focuses on safety and tolerability while measuring pharmacokinetics, pharmacodynamics, and immunogenicity. Investigators will also collect preliminary clinical activity data to look for symptom improvement. Findings will guide dosing and the design of larger efficacy trials if results are promising.

Who should consider this trial

Good fit: Adults (≥18 years) with generalized myasthenia gravis (MGFA Class II–IVa), an MG-ADL score ≥5 with non-ocular items ≥50% and GMG ≥11, and who have had inadequate responses to corticosteroids, immunosuppressants, or biologics are the intended candidates.

Not a fit: Patients with prior CAR-T or T-cell engager therapies, those judged likely to need respiratory support, or those with recent use of excluded immunosuppressive drugs are not expected to benefit or may be ineligible.

Why it matters

Potential benefit: If successful, cizutamig could become a new treatment option that improves symptoms for patients with gMG who do not respond to current therapies.

How similar studies have performed: While other targeted immunotherapies have shown benefit in gMG, cizutamig is a novel agent with limited prior clinical data.

Eligibility criteria

Inclusion Criteria:

1. At least 18 years old at the time of signing the Informed Consent Form (ICF);
2. Diagnosed with MG, classified as MGFA Class II-IVa, and judged by the investigator as unlikely to require respiratory support during the study;
3. At screening, the Myasthenia Gravis Activities of Daily Living (MG-ADL) score ≥ 5, with non-ocular items accounting for ≥ 50% of the total score, and GMG ≥ 11;
4. Inadequate response to conventional therapies or lack of effective treatment options, defined as disease recurrence or progression despite treatment with corticosteroids, immunosuppressants (e.g., azathioprine, mycophenolate mofetil, tacrolimus, cyclosporine A, methotrexate), or biologics (e.g., rituximab), and/or lack of effective treatment methods.

Exclusion Criteria:

1. Any history of CAR-T or TCE therapy targeting any antigen or BCMA-targeted therapy;
2. Use of any approved immunosuppressive drugs not listed here within 12 weeks or 5 half-lives (whichever is longer) before screening, unless approved by the medical monitor;
3. Participation in any investigational trial involving non-biological agents within 4 weeks or 5 half-lives (whichever is longer) of the investigational product (IP) before screening;
4. Participation in any investigational trial involving biological agents within 12 weeks or 5 half-lives (whichever is longer) of the IP before screening;
5. Administration of live vaccines within 4 weeks before screening;
6. History of progressive multifocal leukoencephalopathy;
7. History of primary immunodeficiency (e.g., hypogammaglobulinemia) or hereditary complement deficiency;
8. Presence of one or more significant concurrent diseases, as judged by the investigator, including but not limited to:

   1. Poorly controlled diabetes
   2. Chronic kidney disease stages IIIb, IV, or V
   3. Severe chronic pulmonary disease (e.g., requiring supplemental oxygen) or respiratory failure
9. Any severe medical condition or clinically significant laboratory abnormality that, in the judgment of the investigator or medical monitor, would compromise the patient's safe participation and completion of the study or may affect protocol compliance or interpretation of study results.

Where this trial is running

Shanghai, Shanghai Municipality

• Huashan Hospital Affiliated to Fudan University — Shanghai, Shanghai Municipality, China (Recruiting)

Study contacts

• Study coordinator: xiao dai

Conditions Generalized Myasthenia Gravis