Clinical trial NCT06685055: Markers of Favorable Response to FcRn Inhibitors(INFORM)
Official title: Identification of Clinical, Biological, Cellular and Genetic Markers of Favorable Response to Therapy With Neonatal Fc Receptor Inhibitors for Immunoglobulins (FcRn) in Patients With Generalized Myasthenia Gravis (INFORM)
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Myasthenia Gravis Generalized
Lead sponsor: Fondazione Policlinico Universitario Agostino Gemelli IRCCS
Sponsor class: OTHER
First posted: 2024-11-12
Enrollment: 50
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients with generalized Myasthenia Gravis positive for anti-AChR antibodies undergoing therapy with FcRn inhibitor drugs

Brief summary: Myasthenia gravis is an autoimmune neurological disease caused by autoantibodies primarily directed against components of the postsynaptic membrane of the neuromuscular junction. Approximately 85% of patients have antibodies directed against the acetylcholine receptor (anti-AChR).

Anti-AChR antibodies act through three distinct mechanisms:

1. Activation of the classical complement pathway: Formation of membrane-attack complexes (MACs) results in the destruction of the postsynaptic membrane.
2. Mechanical blockade: Anti-AChR antibodies block the acetylcholine binding site on its receptor.
3. Internalization and lysosomal degradation: Bivalent IgG causes cross-linking of adjacent receptors leading to internalization and degradation of AChRs (antigenic modulation).

Patient mortality has significantly reduced due to effective treatments preventing severe exacerbations of myasthenic symptoms.

In the past five years, the FDA and EMA have approved complement inhibitors and FcRn inhibitors for treating generalized myasthenia gravis with anti-AChR antibodies. Many other therapies are currently in phase 3 clinical trials or under regulatory review. However, there is no specific evidence to support which patients benefit most from one treatment class over another.

Given their relative efficacy compared to conventional therapies and high costs, their future role in the therapeutic arsenal is unclear. A personalized approach considering the different pathogenic mechanisms of anti-AChR and single gene polymorphisms involved in treatment response is essential for effective therapeutic choice. In July 2023, AIFA approved the reimbursement of Efgartigimod in Italy for treating adult patients with generalized myasthenia gravis with anti-AChR antibodies, in addition to standard therapy.

FcRn inhibitors (including Efgartigimod) prevent the interaction of IgG with the neonatal Fc receptor for immunoglobulin fragments, reducing IgG recycling and promoting the degradation of IgG and pathogenic antibodies without affecting albumin levels.

There is heterogeneity among patients in their response to FcRn inhibitors therapies. Currently, there is no specific evidence indicating which patients may benefit most from this class of treatments. Interindividual heterogeneity in the autoantibody repertoire, predominance of different pathogenic mechanisms, and single gene polymorphisms affecting treatment response. Investigating the immune profile and specific gene polymorphisms in myasthenic patients needing these innovative therapies could identify predictive biomarkers and personalize therapeutic choices.


Eligibility criteria: Inclusion Criteria:

- Age ≥18 years.

* Diagnosis of generalized anti-AChR positive Myasthenia Gravis.
* Need for therapy with neonatal Fc receptor inhibitors for immunoglobulins (FcRn) as per AIFA-approved therapeutic indications (14).
* Ability to follow up at the reference center.
* Signed informed consent for the study.

Exclusion Criteria:

* Age \&lt;18 years.

  * Poor compliance with drug therapy.
  * Concurrent autoimmune diseases.
  * Insufficient availability of clinical information.
  * Ongoing neoplasm or infection at the time of biological sample collection.
  * Refusal to sign the informed consent for the study.

Primary outcomes:
measure: Identification of Clinical Markers of Favorable Response to FcRn Inhibitors Therapy in Patients With Generalized Myasthenia Gravis
timeFrame: 24 months
measure: Identification of Biological and Cellular Markers of Favorable Response to FcRn Inhibitors Therapy in Patients With Generalized Myasthenia Gravis
timeFrame: 24 months
measure: Identification of Biological and Cellular Markers of Favorable Response to FcRn Inhibitors Therapy in Patients With Generalized Myasthenia Gravis
timeFrame: 24 months
measure: Identification of Biological and Cellular Markers of Favorable Response to FcRn Inhibitors Therapy in Patients With Generalized Myasthenia Gravis
timeFrame: 24 months
measure: Identification of Genetic Markers of Favorable Response to FcRn Inhibitors Therapy in Patients With Generalized Myasthenia Gravis
timeFrame: 24 months
measure: Identification of Clinical Markers of Favorable Response to FcRn Inhibitors Therapy in Patients With Generalized Myasthenia Gravis
timeFrame: 24 months
Secondary outcomes:
measure: Predictive algorithm of favorable response
timeFrame: 24 months
Other outcomes:
Locations:
city: Rome
country: Italy
facility: Fondazione Policlinico Universitario A. Gemelli IRCCS
Study officials:
affiliation: Fondazione Policlinico Universitario A. Gemelli, IRCCS
name: Raffaele Iorio
role: PRINCIPAL_INVESTIGATOR
References: