Results From 10-Patient Case Study Lead to Phase III Clinical Trial for Patients with Duchenne Muscular Dystrophy
Cedars-Sinai Heart Institute researchers have found that a commonly prescribed drug restores blood flow to oxygen-starved muscles of boys with
Duchenne muscular dystrophy, a genetic muscle-wasting disease that rarely is seen in girls but affects one in 3,500 male babies, profoundly shortening life expectancy. It is the most common fatal disease that affects children.
Muscle weakness begins in early childhood, often causing deformity of the arms, legs and spine. Heart and respiratory muscles often begin to fail before children reach early teen years. Although steroid medications – which often are not well tolerated – and other therapies may ease symptoms and delay the most severe effects, no disease-specific treatment exists, and patients rarely survive into their 30s.
But in this case study of 10 boys with Duchenne muscular dystrophy, also called DMD, a single dose of a drug often prescribed for erectile dysfunction or pulmonary hypertension corrected defective blood vessel mechanisms and restored blood flow to exercising muscles.
“The effects were immediate and dramatic, raising the question: If a single dose restores blood flow to muscle while the drug is in the patient’s system, could ongoing tadalafil administration provide sustained benefits, possibly preserve muscle and slow disease progression? If so, this would offer a new therapeutic strategy for DMD, and we have launched a randomized Phase III clinical trial to find out,” said Ronald Victor, MD, director of the Cedars-Sinai Center for Hypertension, associate director of clinical research at the Heart Institute and the Burns and Allen Chair in Cardiology Research. He is the senior author of a highlighted article in the May 7 online edition of Neurology.
Duchenne muscular dystrophy results from a genetic defect that eliminates a protein called dystrophin in the membranes of muscle cells. For more than 25 years, Victor has studied DMD and a less aggressive but debilitating variant called Becker muscular dystrophy. This form of muscular dystrophy, usually diagnosed in early adulthood, is caused by a reduction, but not absence, of dystrophin.
Victor led a research team that in 2000 discovered that the blood flow abnormality in the muscles of children with DMD was caused by a loss of nitric oxide, a signaling chemical that normally tells blood vessels to relax during exercise, increasing blood flow and oxygenation.
In studies of mice bred to represent diseases of dystrophin deficiency, the researchers found that drugs prescribed for other disorders of blood vessel function could restore muscle blood flow and enable the animals to exercise more, with less muscle injury. Tadalafil, known by the brand names Cialis and Adcirca, and sildenafil, called Viagra and Revatio, have long been approved by the Food and Drug Administration to treat erectile dysfunction and pulmonary hypertension, a serious illness that restricts blood flow to the lungs.
Translating these findings to a human clinical trial, Victor and his colleagues published in 2012 a study showing that tadalafil fully restored blood flow in eight of nine patients with Becker muscular dystrophy.
In the new study, investigators found that when boys with Duchenne muscular dystrophy performed handgrip exercises, the major artery of the arm and the blood vessels in muscles of the forearm failed to respond the way they did in healthy boys of similar ages, 8 to 13. But when the boys with DMD were given a single dose of tadalafil, normal vessel function and blood flow were restored. Similar results occurred when sildenafil, a drug with a similar mechanism of action on vessels but a different chemical structure, was used in place of tadalafil.
“Steroids and cardiac-protective blood pressure medication are increasingly prescribed at early ages for patients with Duchenne muscular dystrophy in an effort to delay by a few years the most devastating effects of the disease. But these treatments have no effect on the blood vessel dysfunction that prevents muscles from getting the oxygen they need,” said Victor. “In contrast, in our study, a single dose of tadalafil or sildenafil had an immediate effect. These are well-studied, well-tolerated drugs that are already on the market. If additional study confirms their benefits, repurposing the drugs for muscular dystrophy patients could quickly transform clinical practice.”
The Latest on: Duchenne muscular dystrophy
[google_news title=”” keyword=”Duchenne muscular dystrophy” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Duchenne muscular dystrophy
- Tick Talk: Patek Philippe minute repeater sells for over $23 million at Only Watch 2024 auctionon May 17, 2024 at 12:00 am
The biennial auction dedicated to funding research for Duchenne muscular dystrophy has raised more than $42 million. Read more at straitstimes.com.
- Israel develops worm-based research method on muscular dystrophyon May 16, 2024 at 12:11 pm
Israeli researchers at the Bar Ilan University (BIU) have developed a platform for modeling deadly human muscular system diseases in worms, the BIU said in a statement on Thursday.
- Jar of Hope staging unique race to save kidson May 15, 2024 at 7:49 am
STATEN ISLAND, N.Y. — Jim Raffone, founder/CEO of JAR of Hope ( https://www.jarofhope.org/ ), will play host to a unique half-marathon to save children with a rare and fatal disease.
- Solid Biosciences Provides First Quarter 2024 Business Update and Financial Resultson May 15, 2024 at 5:30 am
Received Rare Pediatric Disease and Orphan Drug Designation for Duchenne musculardystrophy (Duchenne) gene therapy candidate SGT-003 with ...
- ASGCT 2024: Interview with Frédéric Revah, CEO of Généthonon May 14, 2024 at 7:25 am
Frédéric Revah, PhD, speaks with GEN's managing editor Corinna Singleman, PhD, about Généthon's past and future work in rare diseases.
- Edgewise: Intriguing Drug Candidate, But Consider Selling After Recent Runon May 10, 2024 at 10:49 am
Edgewise reveals strong cash position and progressing clinical-stage programs, sparking a bull run. Find out why this is a good time to sell EWTX stock.
- Duchenne Muscular Dystrophyon May 9, 2024 at 4:59 pm
Rome, MD, MPH, examined how the FDA’s accelerated approval process has moved 5 genetically targeted treatments for Duchenne muscular dystrophy (DMD) through its pipeline despite limited evidence ...
- ASGCT 2024: Kate Therapeutics Unveils Gene Therapy Platform and Product Pipeline Progresson May 9, 2024 at 7:00 am
KateTx debuted less than a year ago with a $51 million Series A round co-led by Westlake Village BioPartners and Versant Ventures.
- Young boy dies in trial for Pfizer Duchenne gene therapyon May 7, 2024 at 2:57 pm
A boy with Duchenne muscular dystrophy died after receiving a Pfizer experimental gene therapy. The company is pausing its trial in older boys.
- Pfizer reports patient death in Duchenne gene therapy studyon May 7, 2024 at 2:49 pm
A young patient died due to cardiac arrest after receiving Pfizer's experimental gene therapy being tested in a mid-stage trial for a muscle-wasting disorder called Duchenne muscular dystrophy(DMD), ...
via Bing News