Trial of Tadalafil in DMD open to participants

Multinational pharmaceutical company Eli Lilly is conducting a phase 3 trial of the drug tadalafil (Cialis), which may help regulate blood flow to muscles, in approximately 300 boys with Duchenne muscular dystrophy (DMD) who are 7-14 years old, able to walk, have adequate cardiac function and meet other study criteria. The rationale for using tadalafil to treat DMD or the related Becker muscular dystrophy (BMD) is that blood flow to exercising muscles appears to be disrupted in these disorders as a downstream effect of any of several mutations in the gene for the muscle protein dystrophin. Drugs such as tadalafil and sildenafil (Viagra) are known to prolong the action of nitric oxide, and in so doing, may improve blood flow to exercising muscles despite the presence of dystrophin gene mutations that cause DMD and BMD. The Lilly-sponsored study will determine whether orally administered tadalafil can slow the decline in walking ability in boys with DMD and will also assess the safety of tadalafil and any side effects that might be associated with it in DMD-affected boys. Participants will be randomly assigned to receive tadalafil at one of two daily dosage levels or to receive a placebo for the first 48 weeks of the study. Participants will then have an option to move into a 48-week extension period during which everyone will receive tadalafil. There are more than 60 study sites, including 22 in the United States, as well as locations in Argentina, Belgium, Canada, France, Germany, Italy, Japan, Korea, the Netherlands, Puerto Rico, the Russian Federation, Spain, Taiwan, Turkey and the United Kingdom.