A Randomized Double Blind, Placebo Controlled, Phase 3 Trial of Tadalafil for Duchenne Muscular Dystrophy

Study ID
STU 062013-030

Cancer Related

Healthy Volunteers

Study Sites

  • UT Southwestern-Other
  • Children’s Medical Center (Dallas, Plano, Southlake)

Kara Lorduy

Principal Investigator
Susan Iannaccone, M.D.


This study is a phase 3, global mutlicenter randomized double blind, placebo controlled parallel 3 arm study to determine the efficacy and safety of tadalafil administered orally once daily in boys with DMD who are already receiving therapy with corticosteriods. Patients will receive drug for 48 weeks in the double blind treatment period, and will then be eligible to enroll into a 48 week open label extension period in which all patients will receive tadalafil and an additional 48 openlabel extension period where they will continue to receive once daily tadalafil tablets. The primary objective is to test the hypothesis thatonce daily tadalafil administered orally for 48 weeks lessens the decline in ambulatory ability as measured by the 6MWD compared to placebo in boys with Duchenne Muscular Dystrophy (DMD). Two doses of tadalafil (0.3mg/kg and 0.6mg/kg) will be compared to placebo.

Participant Eligibility

[1] Males with proven DMD as defined as (Diagnosis of Disease with a record of muscle biopsy showing near-complete dystrophin deficiency (Excluding reverent fibers) by immunohistochemistry and or immunoblot) or record of genentic confirmation of DMD diagnosis from a laboratory certified CAP or CLIA using a DNA diagnostic technique that interrogates all DMD gene exons including but not limited to MLPA, GGH, SCAIP, or HRMCA, a point mutation confimed by complete gene sequencing.
[2] Ages 7-14 years inclusive
[3] Ambulant, defined as baseline 6MWD between 200 and 400 meters inclusive
[4] 6MWD measurements within 20% of each other at a minimum of 2 pre-randomization
[5] Left ventricular ejection fraction (LVEF) >=50% as determined by echocardiogram
obtained at screening, or based on record of an echocardiogram performed within 30 days
of Visit 1 if a copy of the record can be obtained as source documentation for the
screening LVEF
[6] Receiving corticosteroids for a minimum of 6 months immediately prior to screening,
with no significant change in total daily dosage or dosing regimen (except those adjusting
for weight changes) for a minimum of 3 months immediately prior to screening and a
reasonable expectation that total daily dosage and dosing regimen will not change
significantly (except for adjustments for weight) for the duration of the
study. Corticosteroid treatment regimen can be daily, intermittent, high-dose weekend,
or alternate days, but must be consistent with current clinical care recommendations
([7] Written informed consent from parents/legal guardian and written assent from patients