Researchers in Geneva and Strasbourg recently tested tamoxifen, a breast cancer drug, as a treatment for muscle paralysis in a preclinical study.
Myotubular myopathy is a genetic disorder causing muscle paralysis upon birth. With no known treatment, the vast majority of infants with this condition do not live past the age of two. Tamoxifen, a drug currently used to treat breast cancer, has several antioxidant and antifibrotic properties that can aid in protecting muscle fibres.
Due to these properties and previous research done on muscular dystrophy, a team of researchers at the University of Geneva and the University of Strasbourg carried out a new study examining the effects of tamoxifen on myotubular myopathy. Their work was recently published in Nature Communications.
The researchers administered varying doses of tamoxifen to mice with myotubular myopathy and discovered that it significantly increased life expectancy. Upon daily administration of tamoxifen, they found that the average life expectancy doubled at the lowest dose and tripled upon intermediate dosing.
Mice who took the highest dose of tamoxifen lived up to 290 days on average, up to 6 times longer than the untreated mice. In addition to boosting life expectancy, tamoxifen also slowed or even halted the progression of paralysis and tripled the muscular strength of the treated mice.
The research team believes that earlier administration of tamoxifen could be even more effective in treating myotubular myopathy. During the study, they administered the drug when the mice first showed signs of hindleg paralysis. However, administering tamoxifen before symptoms arise could prevent the manifestation of the disease, and a study done with younger mice at Toronto’s Sick Kids Hospital provided evidence in support of this. The researchers hope for a clinical trial to be underway in humans in a few years.
Written by Agustin Dominguez Iino, BSc
- Gayi E et al. Tamoxifen prolongs survival and alleviates symptoms in mice with fatal X-linked myotubular myopathy.Nat Commun. 2018 Nov 19;9(1):4848. doi: 10.1038/s41467-018-07058-4.
- Université de Genève. A molecule for fighting muscular paralysis. EurekAlert! https://www.eurekalert.org/pub_releases/2018-11/udg-amf111618.php