Repurposed Compound to be Tested in Phase 2a Trial in Huntingtons Disease

In an effort to minimize the amount of time that it takes to make new treatments available to those who need them, repurposing drugs is no foreign concept. Especially with rare diseases, such as Huntington’s disease, repurposing drugs offers major potential for placing exciting new therapies on the horizon for the rare, neurodegenerative disease.

One such drug in development is SOM3355, a repurposed compound initially indicated for the treatment of hypertension and angina pectoris. As announced by SOM Biotech, the oral and brain penetrant drug will be entering a phase 2a clinical trial led by Jaime Kulisevsky, MD, PhD, of the Hospital de la Santa Creu i Sant Pau, in Barcelona, Spain, to evaluate its safety and efficacy as a treatment for the chorea movements associated with Huntington's disease.

"Currently, the treatment of movement disorders in Huntington's disease is limited by the side effects of the drugs used,” said lead author, Dr Kulisevsky, in a recent statement. “SOM3355 offers a promising alternative to improve the tools available to treat the disease.”

An acardioselective β1‐adrenoceptor antagonist, SOM3355 is a potent selective inhibitor of Vesicular Monoamine Transporter-2 (VMAT2) that utilizes an artificial intelligence genetic algorithm platform (Phoenix^Ò). By causing a decrease in the levels of dopamine, an essential neurotransmitter in the control of coordinated movements, SOM3355 reduces choreic movements associated with Huntington's disease.

A number of preclinical studies have validated the potential of SOM3355 to have promising clinical efficacy and properties that are likely to avoid the side effects of other VMAT2 inhibitor class members that have led to restricted prescribing.

“The clinical trial that we begin has a double-blind and randomized design that will allow to verify objectively the ability of the drug to improve abnormal movements,” added Dr Kulisevsky. “The participation of 43 centers in our environment will facilitate the recruitment of the sufficient number of patients and guarantee the objectivity of the results."

The phase 2a proof-of-concept trial, is designed as a randomized, double-blind, placebo-controlled trial, which will be comprised of 2 treatment arms and take place over the course of 27 weeks. The central goal of the trial is to evaluate the safety and efficacy of SOM3355 in a total of 30 patients with Huntington's disease with chorea movements.

The primary efficacy point will be measured as an improvement in participants’ Total Maximal Chorea score. The impression of change, functional capacity, gait and motor scores, and secondary endpoints will also be incorporated as measurements in the disease’s different domains.

"We are very proud to start this clinical trial of SOM3355 in Huntington patients,” said Raúl Insa, MD, PhD, SOM Biotech’s founder and CEO. “It will validate for the second time our business model and Phoenix^Ò technology while providing patients with safer and more affordable drugs. The 4 hospitals taking part in the trial are of excellent profile and we are confident that the recruitment will go smoothly."