diff --git a/tests/bugfixes/github/test_CVE_2018_9145.py b/tests/bugfixes/github/test_CVE_2018_9145.py
index 9fc541be1f..7d56a1adb3 100644
--- a/tests/bugfixes/github/test_CVE_2018_9145.py
+++ b/tests/bugfixes/github/test_CVE_2018_9145.py
@@ -1,8 +1,9 @@
 # -*- coding: utf-8 -*-
 
 import system_tests
+import unittest
 
-
+@unittest.skip("Skipping test using option -pR (only for Debug mode)")
 class SubBoxLengthDataBufAbort(metaclass=system_tests.CaseMeta):
 
     url = "https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-9145"
diff --git a/tests/bugfixes/github/test_issue_216.py b/tests/bugfixes/github/test_issue_216.py
index 7d7f29a069..4030e58225 100644
--- a/tests/bugfixes/github/test_issue_216.py
+++ b/tests/bugfixes/github/test_issue_216.py
@@ -1,8 +1,9 @@
 # -*- coding: utf-8 -*-
 
 import system_tests
+import unittest
 
-
+@unittest.skip("Skipping test using option -pR (only for Debug mode)")
 class UncontrolledRecursion(metaclass=system_tests.CaseMeta):
     url = "https://github.com/Exiv2/exiv2/issues/216"
 
diff --git a/tests/bugfixes/github/test_issue_511.py b/tests/bugfixes/github/test_issue_511.py
index 89239b5317..414b46123f 100644
--- a/tests/bugfixes/github/test_issue_511.py
+++ b/tests/bugfixes/github/test_issue_511.py
@@ -1,8 +1,9 @@
 # -*- coding: utf-8 -*-
 
 import system_tests
+import unittest
 
-
+@unittest.skip("Skipping test using option -pR (only for Debug mode)")
 class ThrowsWhenIFDsAreMalformed(metaclass=system_tests.CaseMeta):
     url = "https://github.com/Exiv2/exiv2/issues/511"
 
diff --git a/tests/bugfixes/redmine/test_issue_1108.py b/tests/bugfixes/redmine/test_issue_1108.py
index 02c4be13bc..f78d636841 100644
--- a/tests/bugfixes/redmine/test_issue_1108.py
+++ b/tests/bugfixes/redmine/test_issue_1108.py
@@ -1,7 +1,9 @@
 # -*- coding: utf-8 -*-
 
 import system_tests
+import unittest
 
+@unittest.skip("Skipping test using option -pR (only for Debug mode)")
 class CheckDumpSubFiles(metaclass=system_tests.CaseMeta):
 
     url = "http://dev.exiv2.org/issues/1108"