Voyager Therapeutics is trading at $2.00, down 8.66%, in after-hours trading; the catalyst remains unclear. - No company-specific announcement dated October 20 has been identified to explain the decline; the investor-relations page lists no release later than September 1. - The regular-session close was $2.19, following two consecutive gains, but that trend does not explain the after-hours reversal. - Major U.S. indexes finished higher, and after-hours volume was unavailable.