Wednesday, Sepracor Inc. (SEPR) said its Phase II clinical trail to evaluate efficacy and safety of SEP-225289 for treatment of major depressive disorder did not meet the primary end-point.
The Marlborough, Massachusetts-based Sepracor said that the experimental depressive disorder drug did not meet the primary efficacy endpoint of reducing symptoms of depression following eight weeks of treatment, as assessed on the clinician-rated 17-item HAM-D scale. The positive control in the study did achieve separation from placebo that was statistically significant on the primary endpoint.
SEP-225289 is a member of a relatively new class of pharmacologic agents referred to as triple reuptake inhibitors based on their activities at the serotonin, norepinephrine and dopamine transporters.
Sepracor said that the measured serum concentrations of SEP-225289 in the study were found to be below expected levels of exposure for both doses studied and were well below exposure profiles observed in several Phase I studies.
In addition, the adverse event profile demonstrated by SEP-225289 was inconsistent with prior clinical experience and was similar to the side effect profile observed when patients were administered placebo. As such, preliminary data are inconclusive pending further investigation of the dose exposure relationship of SEP-225289.
The pharmacological profile of SEP-225289 is distinct from all other currently approved antidepressant agents due to its significant affinity for the dopamine transporter as well as its high potency reuptake inhibition at the serotonin and norepinephrine transporters.
SEPR closed Wednesday's regular trading session at $17.89, up $0.55 or 3.17%, on a volume of 2.7 million shares. In after-hours, the stock, however, lost $2.62 or 14.65%, and traded at $15.27.
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