GMG

The importance of using multiple measures for gMG patients¹

Using aCombination of physician-evaluated tools

such as the QMG and patient-reported outcome as the MG-ADL

Or use Composite measures

Such as the MGC may provide amore comprehensive picture of patient's disease status

MGFA-PIS

can be used to assess clinically whether patients with MG achieve minimal manifestations, “ pharmacologic remission ” or worsening following treatment.

^aMinimal manifestations is defined as the patient having no symptoms or functional limitations from MG but some weakness on examination of some muscles; this acknowledges that some patients, who otherwise meet the definition of remission, have mild weakness.^2,3

According to MGFA clinical classification, there are 5 main classes for MG

Class I

Any ocular muscle weakness; may have weakness of eye closure; all other muscle strength is normal

Class II

Mild weakness affecting muscles other than the ocular muscles; may also have ocular muscle weakness of any severity

Class III

Moderate weakness affecting muscles other than the ocular muscles; may also have ocular muscle weakness of any severity

Class IV

Severe weakness affecting muscles other than the ocular muscles; may also have ocular muscle weakness of any severity

Subclass “a” (IIa/IIIa/IVa): Predominantly affecting limb muscles, axial muscles, or both; may also have lesser involvement of the oropharyngeal muscles

Subclass “b” (IIb/IIIb/IVb): Predominantly affecting the oropharyngeal muscles, respiratory muscles, or both; may also have lesser or equal involvement of limb muscles, axial muscles, or both

Class V

Intubation, with or without mechanical ventilation, except when employed during routine post-operative management.

Feeding tube use without intubation places the patient in Class IVb

Definition of highly active patients

HIGHLY ACTIVE MG PATIENTS DESPITE ADEQUATE COURSE-MODIFYING AND SYMPTOMATIC THERAPY IS DEFINED AS ONE OF THE FOLLOWING

MGFA status ≥IIb.and/or≥2 recurrent severe exacerbationsorMyasthenic crises in the last year since diagnosis

MGFA status ≥IIa. AndMGFA status ≥IIa. Severe exacerbation orMyasthenic crises in the last year

MGFA status ≥IIa for ≥ 2 years

MGFA-II Mild weakness affecting muscles other than the ocular muscles; may also have ocular muscle weakness of any severity

gMG, generalized myasthenia gravis; MG, myasthenia gravis; MG-ADL, Myasthenia Gravis Activities of Daily Living scale, MGC, Myasthenia Gravis Composite scale; MGFA, Myasthenia Gravis Foundation of America; PIS, post-intervention status; QMG, Quantitative Myasthenia Gravis scale.

References: