Efgartigimod for hospitalized myasthenia gravis exacerbations or crisis

Treatment of Myasthenia Gravis Exacerbation or Crisis With Efgartigimod: A Single Arm, Open Label Prospective Cohort Study

This will try giving efgartigimod in the hospital to see if it helps adults with AChR‑positive generalized myasthenia gravis who are admitted for a severe worsening of symptoms.

Quick facts

• Phase: PHASE4
• Study type: Interventional
• Enrollment: 20 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: University of Colorado, Denver (other)
• Drugs / interventions: ravulizumab, eculizumab
• Locations: 1 site (Aurora, Colorado)
• Trial ID: NCT06860633 on ClinicalTrials.gov

What this trial studies

Hospitalized adults with AChR‑positive generalized myasthenia gravis who meet severity thresholds (for example QMG ≥11 or MG‑ADL ≥6) are enrolled within 24 hours of admission to receive efgartigimod. Researchers will track clinical recovery using validated scales such as the Quantitative Myasthenia Gravis (QMG) score and MG‑ADL, and will measure blood markers including circulating IgG and AChR antibody levels. The rationale is that efgartigimod reduces IgG similarly to plasma exchange, so it may speed symptom improvement without invasive apheresis. The work is conducted at the University of Colorado Aurora site in hospitalized patients and focuses on acute management rather than chronic outpatient dosing.

Who should consider this trial

Good fit: Adults (≥18) with generalized AChR‑antibody positive myasthenia gravis who are hospitalized for a worsening of weakness (e.g., QMG ≥11 or MG‑ADL ≥6) and can be enrolled within 24 hours of admission are the ideal candidates.

Not a fit: Patients without AChR antibodies, those with isolated ocular MG, those not requiring hospitalization for exacerbation, or people unable to enroll within the 24‑hour window are unlikely to be eligible or to benefit in this protocol.

Why it matters

Potential benefit: If successful, efgartigimod could offer a less invasive, drug-based hospital treatment that lowers pathogenic antibodies and speeds recovery from MG exacerbations, potentially reducing or replacing plasma exchange for some patients.

How similar studies have performed: Efgartigimod is FDA‑approved and has shown benefit for chronic AChR‑positive generalized MG by lowering IgG and improving symptoms, but its use for acute hospitalized exacerbations is a novel application that has not been well studied.

Eligibility criteria

Inclusion Criteria:

* Adults ≥ age 18 years with known generalized MG as identified by characteristic signs of generalized MG on clinical assessment and positive serology for AchR antibodies as well as one of the following:

  1. Documented positive response to cholinesterase inhibitors such as pyridostigmine or edrophonium
  2. Abnormal decrement on slow repetitive nerve stimulation testing
  3. Abnormal single fiber EMG
* Evidence of worsening weakness requiring hospital admission for stabilization and change in therapy as determined by a neuromuscular expert including:

  1. Quantitative Myasthenia Gravis (QMG) scale ≥ 11
  2. MG-ADL score ≥ 6
  3. Worsening weakness that is unlikely to be ameliorated by adjustment of current medications including impaired respiratory status, dysarthria, dysphagia, difficulty chewing, limb weakness, diplopia, ptosis.
* Ability to sign consent and be enrolled within 24 hours of hospital admission. For participants transferred to University of Colorado Hospital, the time of admission/presentation to the outside hospital is counted towards this 24-hour cap.

Exclusion Criteria:

* MG worsening thought to be related to active infection or due to medications (e.g. fluoroquinolone or aminoglycoside antibiotics, magnesium, chloroquine derivatives)
* Intubation prior to ability to sign informed consent or intubation within 24 hours of hospitalization
* Use of IVIG within 2 weeks, or having undergone plasma exchange or received efgartigimod in the 4 weeks prior to admission
* Current ongoing use of ravulizumab or eculizumab (monoclonal antibody C5-complement inhibitors).
* Other medical conditions that, in the opinion of the investigator and treating clinicians, might interfere with the validity of assessment measures used in the study (e.g. steroid myopathy, CNS pathology, severe arthritis, fractures, etc.). This criterion is a standard exclusion in MG trials and relates solely to other conditions that reduce muscle power or range of motion and would thus worsen scores on assessment measures like the QMG due to non-MG conditions.
* Known history of coagulopathy, blood clotting, recent severe bleeding (e.g. GI bleed).
* Pregnancy or breastfeeding. Pregnancy must be excluded for all potential participants who are able to become pregnant prior to initiation of treatment.
* IgG levels \< 600mg/dL
* Evidence of active or chronic Hepatitis B infection, untreated Hepatitis C infection, HIV with low CD4 (\<200) count.

Where this trial is running

Aurora, Colorado

• University of Colorado — Aurora, Colorado, United States (RECRUITING)

Study contacts

• Principal investigator: Thomas Ragole, MD — University of Colorado, Denver
• Study coordinator: Alyssa Avilez, BS

Conditions: Myasthenia Gravis Crisis, Myasthenia Gravis Exacerbations, AChR Myasthenia Gravis, myasthenia exacerbation, efgartigimod