New Potential Treatment for Muscular Dystrophy Appears to Be Safe

Mar 11, 2008

Myostatin, a protein that blocks muscle growth, has shown promising results as a potential therapeutic target for treating muscular dystrophy in animal studies, where its inhibition led to increased muscle mass and strength. A new study, the first to evaluate a myostatin inhibitor in patients, assessed its safety in adults with muscular dystrophy and found that it was well-tolerated. The study was published today in Annals of Neurology, the official journal of the American Neurological Association.

Muscular dystrophy is an inherited disorder involving progressive muscle weakness and wasting. Although there has been progress in understanding the pathology of this disease, no drug treatments that increase muscle strength have been found. In addition, very few trials have been conducted for muscular dystrophy that begins in adulthood, and none of these involved novel drugs.

A double-blind, randomized study of 116 patients with muscular dystrophy was conducted by researchers from 10 centers in the United States and United Kingdom. Patients with multiple different types of muscular dystrophy were divided into four groups given sequentially higher doses of a myostatin inhibitor called MYO-029 produced by Wyeth Pharmaceuticals. Each group was randomized to receive the test drug or a placebo in a 3:1 ratio. The drug or placebo was administered intravenously every two weeks for six months, after which the patients were followed for three months. Although the purpose of the study was to test for safety, muscle strength and mass were also assessed.

The results showed that safety assessments, including vital signs, laboratory tests and physical examination showed no significant differences between treatment and placebo groups. There were no side effects to skeletal, smooth or cardiac muscle, and the most significant side effects related to the treatment were hypersensitivity skin reactions (such as hives).

No increase in muscle strength or improvement in function was seen during the nine months of the study, although muscle mass did increase in some of the patients. Because the sample sizes in the different dosage groups were small, differences between the groups did not reach statistical significance. “However, the consistency of the response to treatment in the various measures of effects on muscle tissue suggests that MYO-029 reached its intended target, producing a modest degree of muscle fiber hypertrophy and increased muscle mass in some treated subjects,” noted Kathryn R. Wagner of The Johns Hopkins University School of Medicine and her coauthors. They add that larger studies over longer periods of time would be necessary to properly evaluate the efficacy of this new treatment.

“This trial supports the hypothesis that systemic administration of myostatin inhibitors provides an adequate safety margin for clinical studies, and these inhibitors should be evaluated for stimulating muscle growth in muscular dystrophy,” the authors conclude. They note that additional muscle inhibitors are in development and clinical trials for other muscle-wasting conditions, and further evaluation of more powerful myostatin inhibitors for muscle disorders should be considered.

Article: “A Phase I/II Trial of MYO-029 in Adult Subjects with Muscular Dystrophy,” Kathryn R. Wagner, James L. Fleckenstein, Anthony A. Amato, Richard J. Barohn, Katharine Bushby, Diana M. Escolar, Kevin M. Flanigan, Alan Pestronk, Rabi Tawil, Gil I. Wolfe, Michelle Eagle, Julaine M. Florence, Wendy M. King, Shree Pandya, Volker Straub, Paul Juneau, Kathleen Meyers, Cristina Csimma, Tracey Araujo, Robert Allen, Stephanie A. Parsons, John M. Wozney, Edward R. La Vallie, Jerry R. Mendell, Annals of Neurology, 2008.

Source: Wiley

Explore further: Research shows that magnetic resonance helps to detect and quantify fat in liver

add to favorites email to friend print save as pdf

Related Stories

Scientists make diseased cells synthesize their own drug

Sep 02, 2014

In a new study that could ultimately lead to many new medicines, scientists from the Florida campus of The Scripps Research Institute (TSRI) have adapted a chemical approach to turn diseased cells into unique manufacturing ...

Need muscle for a tough spot? Turn to fat stem cells

Jan 27, 2012

(PhysOrg.com) -- Stem cells derived from fat have a surprising trick up their sleeves: Encouraged to develop on a stiff surface, they undergo a remarkable transformation toward becoming mature muscle cells. ...

How muscle develops: A dance of cellular skeletons

Jun 04, 2011

Revealing another part of the story of muscle development, Johns Hopkins researchers have shown how the cytoskeleton from one muscle cell builds finger-like projections that invade into another muscle cell's territory, eventually ...

Recommended for you

Nanopatch to help WHO battle polio

4 hours ago

The World Health Organisation's (WHO) battle against polio has a new weapon after joining forces with Vaxxas, the biotechnology company responsible for developing revolutionary vaccine delivery method the Nanopatch.

Obama's Ebola response: Is it enough and in time?

8 hours ago

President Barack Obama declared Tuesday that the Ebola epidemic in West Africa could threaten security around the world, and he ordered 3,000 U.S. military personnel to the region in emergency aid muscle ...

First domestic case of chikungunya in Brazil

8 hours ago

Brazil's authorities on Tuesday reported the first domestically contracted cases of the mosquito-borne chikungunya virus, prompting the government to announce it was stepping up attempts to control the disease.

Australia promises $6.4 million to fight Ebola

9 hours ago

Australia announced on Wednesday it will immediately provide an additional 7 million Australian dollars ($6.4 million) to help the international response to the Ebola outbreak in West Africa.

User comments : 0