According to Yanick Roy, studio director at Bioware Montreal, Mass Effect 4 is in development at halfway. Considering this Eurogamer affirmed that the game should release in October 2015.
There hasn’t been established a name for the game so that everybody is calling it Mass Effect 4. Bioware said also that the earlier games in the franchise will be respected even if we don’t now until now if the story of the new game continues the old one or it precedes it. Hope the game will be as good as the other ones.