A Study to Investigate the Effectiveness and Safety of Injectafer for the Treatment of Restless Legs Syndrome


About this study

The purpose of this study is to assess the safety and effectiveness of Ferric Carboxymaltose Injectafer for the treatment of restless legs syndrome.

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.

Inclusion Criteria

  • Male or female 
  • Age ≥ 18
  • Able to give informed consent to the study
  • Restless legs syndrome symptoms affirming diagnosis
  • Must meet IRLS Diagnostic Criteria
    • An urge (distressing need) to move the legs usually associated with painful or uncomfortable sensations in the legs
    • Urge to move may be present without the uncomfortable sensations
    • Arms or other body parts may be involved in addition to the legs
    • Urge to move or unpleasant sensations are worse or exclusively present at rest or inactivity, such as lying down or sitting
    • Urge to move or unpleasant sensations are partially/temporarily relieved with walking or moving the legs
    • Urge to move or unpleasant sensations are worse in the evening or night than during the day or only occur in the evening or night
    • When symptoms are severe, the worsening at night may not be noticeable but must have been previously present.
  • Should be on a stable (FDA approved) RLS treatment for at least 8 weeks prior to screening
  • Score ≥ 15 on the IRLS Rating Scale at screening and on day 0 prior to dosing
  • If on anti-depressants and sleep medications must be on a stable dose for at least 6 months
  • Has regular sleep hours between 9 pm and 9 am
  • If at risk for pregnancy
    • Must have a negative pregnancy test at baseline 
    • Have had a hysterectomy, tubal ligation, or otherwise be incapable of pregnancy
    • Have practiced any of the following methods of contraception for at least one month prior to study entry
      • Hormonal contraceptives
      • Spermicide and barrier
      • Intrauterine device
      • Partner sterility

Exclusion Criteria

  • RLS secondary to other CNS disease or injury, including peripheral neuropathy and neurodegenerative disorders
  • Stage 4 - 5 CKD, on dialysis or anticipated to start dialysis while participating in this study
  • Any pain related (e.g., frequent muscle cramps, myalgia, fibromyalgia) or sleep related disorders (e.g. sleep apnea, unless on stable CPAP) which may confound the outcome measures
  • History of neuroleptic akathisia
  • Parenteral iron use within 6 weeks prior to screening
  • History of > 10 blood transfusions in the past 2 years
  • Anticipated need for blood transfusion during the study
  • Known hypersensitivity reaction to any component of Injectafer® (Ferric Carboxymaltose)
  • Previously randomized to Injectafer® (FCM or VIT-45) in a clinical trial
  • Current acute or chronic infection other than viral upper respiratory tract infection
  • Malignancy other than basal or squamous cell skin cancer, or has been cancer free for ≥ 5 years
  • Pregnant or lactating
  • Seizure disorder currently being treated with medication
  • Baseline ferritin ≥ 300 ng/mL
  • Baseline TSAT ≥ 45%
  • History of hemochromatosis or hemosiderosis or other iron storage disorders
  • AST or ALT greater than 2 times the upper limit of normal
  • Hemoglobin greater than the upper limit of normal
  • Known positive hepatitis B antigen (HBsAg) or hepatitis C viral antibody (HCV) with evidence of active hepatitis (i.e., AST/ALT greater than the upper limit of normal)
  • Known positive HIV-1/HIV-2 antibodies (anti-HIV)
  • Received an investigational drug within 30 days before randomization
  • Chronic alcohol or drug abuse within the past 6 months
  • Any other pre-existing laboratory abnormality, medical condition or disease which in view of the investigator makes participation in this study put the subject at risk
  • Unable to comply with the study requirements

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

Scottsdale/Phoenix, Ariz.

Mayo Clinic principal investigator

Erika Driver-Dunckley, M.D.

Closed for enrollment

More information


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Additional contact information

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