diff --git a/setup.py b/setup.py
index 9a51e7c..53729af 100644
--- a/setup.py
+++ b/setup.py
@@ -79,7 +79,7 @@ PACKAGE_DESCRIPTION_SHORT = """
 Conversion script from various messaging formats to markdown.""".strip()
 
 def parse_version_file(text: str) -> str:
-    text = re.sub('^#.*$', '', text)
+    text = re.sub('^#.*', '', text, flags=re.MULTILINE)
     match = re.match(r'^\s*__version__\s*=\s*(["\'])([\d\.]+)\1$', text)
     if match is None:
         msg = 'Malformed _version.py file!'