Repligen has started its Phase 1b clinical study of RG3039 for spinal muscular atrophy (SMA) licensed from Families of SMA (FSMA).
The study is designed to evaluate the safety and plasma pharmacokinetics (PK) of multiple doses of RG3039, an orally bioavailable small molecule inhibitor of an RNA-processing enzyme called DcpS in healthy volunteers.
FSMA invested $13m funding and directing the preclinical development of RG3039.
Repligen president and chief executive officer Walter Herlihy said: "Completion of this stage of the RG3039 clinical development programme in healthy volunteers, if successful, will provide the necessary foundation for more advanced trials involving SMA patients who are in critical need of a treatment for this devastating disease."
This double-blind, placebo-controlled, ascending multiple dose study being conducted at the Jasper Clinic in Kalamazoo, Michigan, will randomise each of 32 adult healthy volunteers with ascending oral doses of either RG3039 or a placebo.
According to the study design, within each of the four dose cohort, six subjects will be exposed to oral doses of RG3039 and two subjects to placebo for 28 days.
The correlation of RG3039 PK with a panel of molecular biomarkers, and determination of the inhibitory plasma concentrations of RG3039 for the target enzyme DcpS are the secondary objectives.
RG3039 has been shown to increase production of the SMN protein in cells derived from patients besides improving motor neuron pathology, mobility and lifespan in animal models of SMA.