Effect of Pyridostigmine (Mestinon) on Muscle Strength in Myasthenia Gravis

University of Aarhus

Status and phase: Unknown; Phase 4

Conditions: Myasthenia Gravis

Treatments: Drug: Pyridostigmine; Drug: Placebo oral capsule

Study type: Interventional

Funder types: Other

Identifiers

NCT03510546

Mestinon2018

Details and patient eligibility

About

A randomized, placebo-controlled, double-blinded cross-over study evaluating and quantifying the effect of pyridostigmine on muscle strength and symptoms in Myasthenia Gravis (MG)

Full description

The study aims to evaluate and quantify the effect of pyridostigmine on symptoms and muscle strength in newly-diagnosed patients and patients on stable medication.

Pyridostigmine treatment is initiated in the vast majority of MG patients. No studies have quantified the effect in a randomized trial, and no studies have examined the potential difference in effect in newly diagnosed patients as compared to patients on stable, antimyasthenic medications.

The study will investigate the effect in two groups

Newly diagnosed, treatment-naive patients. MG patients on stable antimyasthenic medication.

Enrollment: 44 estimated patients

Sex: All

Ages: 18 to 90 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• MG verified by a) anti-body, or b) single-fiber EMG and/or decrement on ENG.

Exclusion criteria

• Anti-MuSK
• Known cardio-pulmonary disease
• Known neuropathy
• Known myopathy
• Known malignant disease
• Pregnancy or breastfeeding
• Mechanic ileus, urinary tract obstruction, peritonitis

De-novo MG Eligibility Criteria

• MG diagnosis < 2 months, no prior antimyasthenic medications

Chronic MG Eligibility Criteria

• MG diagnosis > 1 year, and stable pyridostigmine dosis

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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44 participants in 2 patient groups, including a placebo group

Active

Experimental group

Description:

De-novo: Each capsule contains 60 mg. pyridostigmine. 1 capsule is administered twice within 4 hours. Chronic: Each capsule contains 60 mg. pyridostigmine. Number of administered capsules per dosage depend on the patient's usual dosage. Study drug is administered twice within 4 hours. Patients are examined/rated before 1st dose, 1 hour after 1st dose, 1 hour after 2nd dose (Visit 1). After cross-over (Visit 2), patients will be rated open-label at 1 month (Visit 3) and 3 months (Visit 4).

Treatment:

Drug: Pyridostigmine

Placebo

Placebo Comparator group

Description:

Same as "Active", however capsules contain placebo.

Treatment:

Drug: Placebo oral capsule