diff --git a/autoload/vimtex/syntax/p/asymptote.vim b/autoload/vimtex/syntax/p/asymptote.vim
index 70ad323a7e..ae723a1a8f 100644
--- a/autoload/vimtex/syntax/p/asymptote.vim
+++ b/autoload/vimtex/syntax/p/asymptote.vim
@@ -6,7 +6,7 @@
 
 function! vimtex#syntax#p#asymptote#load(cfg) abort " {{{1
   call vimtex#syntax#core#new_env({
-        \ 'name': 'asy\(def\)?',
+        \ 'name': 'asy\(def\)\?',
         \ 'region': 'texAsymptoteZone',
         \ 'nested': 'asy',
         \})
diff --git a/test/test-syntax/test-asymptote.vim b/test/test-syntax/test-asymptote.vim
index c6e0d952f5..242c5bd29c 100644
--- a/test/test-syntax/test-asymptote.vim
+++ b/test/test-syntax/test-asymptote.vim
@@ -5,5 +5,5 @@ set runtimepath^=.
 EditConcealed test-asymptote.tex
 
 if empty($INMAKE) | finish | endif
- 
+
 call vimtex#test#finished()