Zuranolone to face challenges in Japan’s MDD market

Japanese pharma major Shionogi (TYO: 4507) last month submitted a New Drug Application(NDA) in Japan for zuranolone, a gamma aminobutyric acid (GABA) type A receptor subunit agonist in development for major depressive disorder (MDD).

Despite its rapid onset of action, zuranolone is expected to face challenges in Japan’s MDD market due to its severe side effect profile, according to pharma analytics company GlobalData.

In Japan, the standard of care (SOC) treatments for MDD are selective serotonin reuptake inhibitors (SSRI) and serotonin-norepinephrine reuptake inhibitors (SNRI), which typically take four to six weeks to work. Following inadequate response to SOC, drugs with differentiated mechanisms, such as zuranolone, are typically prescribed as a second-line treatment. However, zuranolone is unlikely to displace first-line antidepressants for MDD treatment due to their long history of use, well-established clinical profiles, and widely available cheap generic alternatives.