The Northern Irishman was due to fight Fabian Orozco but was ruled out of the bout after losing to Julian Aristule last month, and Frampton will now meet Briceno at Wembley.
"Everth Briceno is a great fighter. The guy has fought for the world title on two separate occasions," Frampton told reporters.
"He also boxed Leo Santa Cruz who is a future rival of mine, so I aim to do a better job on Briceno than Cruz did.
"I am in the best shape of my life right now. I am improving in training every day, sparring great, and I'm looking forward to showcasing my skills at Wembley on the 20th."
Frampton is yet to lose in his 16-fight professional career.