diff --git a/setup.py b/setup.py
index 002cd44..3cf8ed8 100755
--- a/setup.py
+++ b/setup.py
@@ -12,7 +12,7 @@ root_dir = os.path.abspath(os.path.dirname(__file__))
 
 
 def get_version():
-    version_re = re.compile(r"^__version__ = '([\w_.]+)'$")
+    version_re = re.compile(r"^__version__ = '([\w_.-]+)'$")
     with open(os.path.join(root_dir, 'src', 'semantic_version', '__init__.py')) as f:
         for line in f:
             match = version_re.match(line[:-1])