FIRDAPSE maintained muscle strength and improved patients’ perception of their own physical well-being

In two separate Phase 3 clinical trialsclinical studies conducted with patients., FIRDAPSE was tested against a placeboan inactive medication in adult patients with Lambert-Eaton myasthenic syndrome (LEMS).

The two Phase 3 studies were designed as withdrawal trials*:

*Withdrawal trials are used when researchers want to minimize the use of a placebo for ethical or feasibility reasons, and/or in situations where the efficacy can be determined immediately after patients stop taking the medication being studied.


The patients who started and stayed on FIRDAPSE:

  • Maintained their muscle strength
  • Reported feeling better about their physical well-being

Measured by Quantitative Myasthenia Gravis (QMG) score, an objective assessment of arm strength, leg strength, face and neck muscle performance, swallowing, speech, grip strength, forced breathing, gaze impairment, and other measures.

Measured by Subject Global Impression (SGI) score, a patient-reported outcome measure that shows how much they improved with FIRDAPSE compared to the placebo.

FIRDAPSE maintained functional mobility

FIRDAPSE was evaluated in a separate test, the Triple-Timed Up-and-Go (3TUG), which measured how well FIRDAPSE improved the ability of LEMS patients to walk and move.


The 3TUG is a simple, timed test that requires the patient to stand up from a straight-backed armchair, walk 3 meters, turn around and walk back, and sit back down in the chair.

Individuals perform these actions 3 consecutive times without pause. The final measurement is the average time it takes the patient to complete all 3 repetitions.


The patients who received FIRDAPSE took significantly less time to complete the test compared to patients who received the placebo.

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