diff --git a/src/uu/ptx/src/ptx.rs b/src/uu/ptx/src/ptx.rs
index c273b976c..c3bedb266 100644
--- a/src/uu/ptx/src/ptx.rs
+++ b/src/uu/ptx/src/ptx.rs
@@ -31,6 +31,8 @@ const ABOUT: &str = "\
     Mandatory arguments to long options are mandatory for short options too.\n\
     With no FILE, or when FILE is -, read standard input. Default is '-F /'.";
 
+const REGEX_CHARCLASS: &str = "^-]\\";
+
 #[derive(Debug)]
 enum OutFormat {
     Dumb,
@@ -166,7 +168,11 @@ impl WordFilter {
                         break_set
                             .unwrap()
                             .into_iter()
-                            .map(|c| c.to_string())
+                            .map(|c| if REGEX_CHARCLASS.contains(c) {
+                                format!("\\{}", c)
+                            } else {
+                                c.to_string()
+                            })
                             .collect::<Vec<String>>()
                             .join("")
                     )
diff --git a/tests/fixtures/ptx/break_file b/tests/fixtures/ptx/break_file
index 4c992d40a..499598c20 100644
--- a/tests/fixtures/ptx/break_file
+++ b/tests/fixtures/ptx/break_file
@@ -1 +1 @@
-abc_e
+abc_e^-]\
diff --git a/tests/fixtures/ptx/gnu_ext_disabled_break_file.expected b/tests/fixtures/ptx/gnu_ext_disabled_break_file.expected
index 7afce1861..7ea13471d 100644
--- a/tests/fixtures/ptx/gnu_ext_disabled_break_file.expected
+++ b/tests/fixtures/ptx/gnu_ext_disabled_break_file.expected
@@ -29,6 +29,7 @@
 .xx "" "let's check special characte" "rs:" ""
 .xx "" """quote" "s"", for roff" ""
 .xx "" "oh, and back\sla" "sh" ""
+.xx "" "oh, and back\" "slash" ""
 .xx "" "and" "some other like %a, b#, c$c" ""
 .xx "" "let's check" "special characters:" ""
 .xx "" "let's check special charac" "ters:" ""