Are there any films, novels, or TV series that take place in this universe after Stargate: Universe? If there are none presently, are there any announcements of works in development?
As per Joseph Mallozzi (an Executive Producer on SG-1, SG:A and SGU) in one of his regular "Mail Bag" blog posts:
Fancy Trav writes: “Obviously Stargate Universe is over after 2 seasons. Is that a definate that it is over forever? Has a good run and support so may be able to get it back on? Another network “may” pick it up? Or am I hoping too much and its over for good??”
Answer: Again, sorry to be the bearer of bad news but it is over for SG-1, Atlantis, and Universe.
Yes, there is the Stargate Universe: Back to Destiny comic series
From June 2017 to September 2018, American Mythology Productions produced a six-issue comic series entitled Stargate Universe: Back to Destiny. It is a canon continuation set after the Season 2 finale of the TV show.
Here is the publisher's summary of the first issue:
Stargate Universe the comic book begins right where Season Two of the acclaimed science fiction TV series ended, with the crew and unwilling passengers of Destiny set to cross a vast expanse of space with no margin for error. With almost all of the crew of the ancient starship Destiny in suspended animation, only Eli Wallace is left awake to repair his own stasis pod before time runs out. While he races against time, a new and unexpected danger threatens the fragile plan designed to keep everyone alive and away from the aliens who had been pursuing them. What strange new menace confronts Eli, Colonel Young, Doctor Rush and the others? You’ll have to pick up this issue to find out!
While the extant 3 series may be done for on the small screen...
It's highly likely that there will be semi-canonical novels; there have been for the other series. They usually get announced once the manuscript is sent for layout.
Likewise, it's possible there will be comics.
It's quite possible that a further SG derivative may be done later.
Whether they're set after SGU is yet to be seen, but it's highly likely, as that means far less canon to avoid.
But none of these are announced yet that I've heard of. Wait and see...
There is indeed at least one short-lived franchise which takes place after SGU: Stargate Infinity is set in the future.
That said, it's not actually considered canon. Sadly, I've never seen it myself, so I can't comment on its quality.
The show's producer Joseph Malozzi has confirmed that there are no plans to further the series. In addition to confirming the death of the SG:U TV series (with the striking of the sets and the dismissal of the staff) he's also revealed his tentative plotlines for the third season.
The sole author of an SG:U novelisation; J.M.Swallow confirmed in this blog post that despite his desire (and presumably his request) to write further books within the same universe, he was unable to do so due to internal rights wranglings at MGM post their bankruptcy in 2010:
KEK: I'm guessing it's because the first one sold really poorly. It's a stupid indicator really though, as it was only a novelization of the pilot. Hardly indicative of the sort of number they could expect if they made a genuine canon continuation in novel form.
JMSwallows : Actually, as I understand it, the Air novelization sold fairly well...
KEK : How do you know that?
JMSwallows : Because I wrote it.
On the upside, there will be more Stargate films in the near future. so there will almost certainly be additional novelisations to read.
There is nothing concrete for what happened after the end of SGU. There were several plans on the part of the show's producers, writers, and staff as to how to continue it, though.
The one they seem to have been going for was that three years later, everyone would come to and find Eli half-crazy and living in the shuttle.
Once the series ended, and they were trying to make a straight-to-DVD movie, the plan seemed to be "The gate from the Milky Way is open, and tons of people and supplies from the SGC pour through, including some characters we know." That, too, was set "Three years later."
When the season 3 and movie options had expired, one of the producers simply said, "They'll wake up in a hundred years."
I would like to point out that the director of the original movie that sold the rights to mgm, has said that sg-1, atlantis, and universe are NOT considered canon in his opinion to the original movie. Which gives cause for the possible movie trilogy reboot I've been reading about that would actually be canon.
MGM has released 10 short episodes called Stargate:Origins earlier this year.
It was announced on July 20, 2017 at the 2017 San Diego Comic Con as part of Stargate SG-1's 20th anniversary celebration. The series consists of 10 episodes, each 10 minutes in length, essentially a 10-episode feature length movie, and expands upon the existing mythology of the Stargate franchise.
Stargate Origins premiered with 3 episodes on February 14, 2018 on MGM's Stargate Command subscription service. A 104 minutes long ‘Feature Cut‘ titled Stargate Origins: Catherine was released on June 19, 2018 on digital retail outlets around the world in SD, HD, and 4K formats.
‘Feature Cut‘ additions include a fresh sound mix, enhanced visual effects, a new title sequence, and subtitles in 12 different languages.
There are a number of "new" canon stories set after the end of SGU on television.
First there's the Back to Destiny comic series but also a Back to Pegasus series focused mainly on SGA that also involve the SGC. (I'll warn you that these SGA issues have numerous errors ranging from spelling to continuity and the characters don't look much like themselves but often too much like each other, though I think any fan will still enjoy them.)
There are also several paperback novels that continue the SGA arc but annoyingly these are a totally separate and incompatible canon continuity as the comics.