Scholar Rock, a biotechnology company based in Boston, has announced that they will be investing nearly $50 million to bring SRK-015, a muscle drug for possible treatment of SMA, into human clinical trials. SRK-015 is Scholar Rock’s lead clinical candidate. They expect to start clinical development in the first half of 2018, although timelines for SMA patient trials have not been announced yet.
Researchers believe that the most effective way to treat SMA will be a combination of drugs that address different aspects of the disease. Muscle drugs like SRK-015 could be used alone in certain patient populations or in combination with drugs like Spinraza or AVXS-101, which work to increase the amount of survival motor neuron (SMN) protein in the body. Due to the mutation in the SMN1 gene, individuals with SMA don’t produce this protein at high enough levels.
In data presented at the 2017 Annual SMA Conference, researchers reported that, in a mouse model of SMA, SRK-015 resulted in a 60% increase in muscle force when given in combination with an SMN-enhancing therapy.
More About SRK-015
SRK-015 works by inhibiting myostatin. Myostation is a protein that works with other proteins and hormones to help regulate muscle mass. In healthy individuals, myostation limits muscle growth and differentiation, to prevent muscles from growing too large. For individuals affected by SMA, inhibiting this protein may combat the muscle weakness and atrophy that characterizes the disease.