Humanitarian Device Exemption Post-Approval Study of NeuRx Diaphragm Pacing System for Amyotrophic Lateral Sclerosis


About this study

This post-approval study will follow 60 participants who have ALS, documented chronic hypoventilation, and bilateral phrenic nerve function, and who undergo the surgical implantation procedure to receive the NeuRx Diaphragm Pacing System device. Participants who are successfully implanted with the device will use it for daily diaphragm conditioning sessions. Participants will be followed for at least two years (until the last enrolled participant reaches the 2-year follow-up visit). Safety and probable benefit outcome measures will be assessed.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Study closed to enrollment

Inclusion Criteria:

  1. Age 21 or older.
  2. Participants with familial or sporadic ALS diagnosed as laboratory-supported probable, probable, or definite according to the World Federation of Neurology El Escorial criteria.
  3. Bilateral phrenic nerve function clinically acceptable as demonstrated by bilateral diaphragm movement with fluoroscopic sniff test or with EMG recordings and nerve conduction times.
  4. Chronic hypoventilation was documented by at least one of the following:
    • FVC less than 50% predicted, or
    • |MIP| less than 60 cmH2O, or
    • PaCO2 greater than or equal to 45 mmHg, or
    • Nocturnal SaO2 less than or equal to 88% for at least five continuous minutes
  5. Suitable surgical candidate.
  6. Negative pregnancy test in female participants of childbearing potential.
  7. Informed consent from patient or designated representative.

Exclusion Criteria:

  1. Underlying cardiac or pulmonary disease that would increase the risk of general anesthesia.
  2. Underlying pulmonary diseases that were present prior to ALS that would affect pulmonary tests independent of ALS.
  3. Uncontrolled excessive secretions.
  4. FVC less than 45% predicted at time of surgery.
  5. Preexisting implanted electrical device such as pacemaker or cardiac defibrillator.
  6. Pre-existing diaphragm abnormality such as a hiatal hernia or paraesophageal hernia of abdominal contents going into the thoracic cavity.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Jacksonville, Fla.

Mayo Clinic principal investigator

Kevin Boylan, M.D.

Closed for enrollment

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