The offer, which was originally due to expire on Nov. 25, has now been extended to Dec. 10. All terms and conditions of the offer remain the same, Roche said. So far 14.8% of the shares were tendered.
Roche has put back the deadline several times since it announced the $4.3 billion offer to buy the gene therapy company in February.
(Reporting by John Revill; Editing by Michael Shields)