In an interview with Game Informer (via GameSpot), Mass Effect: Andromeda creative director Mac Walters explained that Andromeda will not kick off another trilogy in the Mass Effect universe.
Ryder, Andromeda's protagonist, follows a vastly different arc than Commander Shepard. Players go to know the latter in media res, well after Shephard had established a reputation as a competent and formidable force in BioWare's fictional universe.
On the other hand, Ryder is wet behind the ears, and follows a more classical hero's journey style of narrative. Once the game ends, BioWare says, Ryder's chapter ends with it.
"At the end of this, we want it to feel like a story has completed," said Walters. "Yes, for the universe, there's much more you could explore, and we want to tease that, but it feels like its own story. It's like, 'Great. I had my Ryder sibling becoming-a-hero story. What's next? Is it going to be Ryder? Is it going to be something else? Who knows?"
Walters gave evasive answers concerning Andromeda's ending: will there be more than one? Will it be controversial enough for players to whine and wheedle until BioWare backpedals and retcons it via an expansion? Walters and his team knows, but they're not telling.
He did confirm that Mass Effect: Andromeda's campaign is fully playable offline, and that crew members and companions cannot die. Walters also said that a co-op campaign is possible in the Mass Effect universe, but did not confirm whether or not Andromeda features such an option.
A cinematic trailer released earlier this week provided an overview of humanity's struggle during Andromeda's timeline.
If you need space-faring adventures to tide you over until Mass Effect: Andromeda releases next year, both Mass Effect 2 and 3 are now backwards compatible on Xbox One.