According to digitalspy.com, the special, which will air Nov. 1 at 9 PM on NBC, is also expected to feature Nora Dunna, Julia Louis-Dreyfus, Laraine Newman, Cheri Oteri, Maya Rudolph and Kristen Wiig.
Clips from past shows will be featured, as will original material.
Dratch's stage credits include Sylvia at New Jersey's George Street Playhouse and Minsky's in Los Angeles. Gasteyer has appeared on Broadway in The Royal Family, Wicked, The Threepenny Opera and The Rocky Horror Show.
As previously reported, "Glee" star Jane Lynch will host the Oct. 9 episode of SNL.
