According to its official website, the new Sailor Moon anime will be broadcast on Niconico starting July 2014.

Some staff were also announced:

Original Creator: Naoko Takeuchi
Director: Munehisa Sakai
Series Composition: Yuuji Kobayashi
Animation Production: Toei Animation
Theme Song: Momoiro Clover Z

Source: Official site

Previous related topic: New Anime 'Bishoujo Senshi Sailor Moon' to Stream Worldwide Winter 2014


Update April 27
According to Nico Live, the new main cast has been announced.

Sailor Moon/Usagi Tsukino: Kotono Mitsuishi
Sailor Mercury/Ami Mizuno: Hisako Kanemoto
Sailor Mars/Rei Hino: Rina Satou
Sailor Jupiter/Makoto Kino: Ami Koshimizu
Sailor Venus/Minako Aino: Shizuka Itou

It was also announced that the anime will be remade and will start streaming on July 5, 2014, ever first and third Saturdays of the month.

Source: Yaraon, ANN

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