diff --git a/lib/pem.js b/lib/pem.js
index 6cde7b4b..e56e406e 100644
--- a/lib/pem.js
+++ b/lib/pem.js
@@ -880,7 +880,7 @@ function generateCSRSubject(options) {
 
     Object.keys(csrData).forEach(function(key) {
         if (csrData[key]) {
-            csrBuilder.push('/' + key + '=' + csrData[key].replace(/[^\w \.\*\-@]+/g, ' ').trim());
+            csrBuilder.push('/' + key + '=' + csrData[key].replace(/[^\w \.\*\-\,@]+/g, ' ').trim());
         }
     });