diff --git a/webapp/api/api/models.py b/webapp/api/api/models.py
index 0bfccd8c..e7749f0f 100644
--- a/webapp/api/api/models.py
+++ b/webapp/api/api/models.py
@@ -114,7 +114,7 @@ def save(self, *args, skip_load=False, **kwargs, ):
         # load the CDB, and raise if this fails.
         if not skip_load:
             try:
-                CDB.load(self.cdb_file)
+                CDB.load(self.cdb_file.path)
             except Exception as exc:
                 raise MedCATLoadException(f'Failed to load Concept DB from {self.cdb_file}, '
                                           f'check if this CDB file successfully loads elsewhere') from exc