Sadly, there just aren't enough visitors to keep the museum open, and its doors will close June 30th. :(
My guess is that most fans make Liverpool a priority for all things Beatles, and tend to make Hamburg a second choice..meanwhile, I just read that someone who visited said that this museum offered rare artifacts from the boys Hamburg days vs. "The Beatlesl Story", which houses present-day memorabilia in contrast. No judgement there; each museum does right by the boys, regardless. It's just a shame that more people haven't been privy to this museum to warrant keeping it open.
http://www.beatlemania-hamburg.com/en/home/