Dec 17 (Reuters) - Tetraphase Pharmaceuticals Inc said its antibiotic drug to treat complicated intra-abdominal infections was as effective as Merck & co Inc's ertapenem in a late-stage study.
The drug, eravacycline, treats infections caused by gram-negative bacteria, a type of antibiotic-resistant pathogens, often called superbugs.
Tetraphase shares were up 14.5 percent at $38 in after-hours trading. They closed up 10.6 percent in regular trade on Wednesday, after touching a record high of $33.22 earlier in the session. (Reporting by Amrutha Penumudi in Bengaluru; Editing by Savio D'Souza)