diff --git a/app/datatables/protocols_datatable.rb b/app/datatables/protocols_datatable.rb
index aea0a38c9..72f1b874b 100644
--- a/app/datatables/protocols_datatable.rb
+++ b/app/datatables/protocols_datatable.rb
@@ -172,7 +172,7 @@ class ProtocolsDatatable < CustomDatatable
   def get_raw_records
     get_raw_records_base.select(
       '"protocols".*',
-      'STRING_AGG("protocol_keywords"."name", \', \') AS "protocol_keywords_str"',
+      'STRING_AGG(DISTINCT("protocol_keywords"."name"), \', \') AS "protocol_keywords_str"',
       'COUNT(DISTINCT("protocol_versions"."id")) + 1 AS "nr_of_versions"', # User assignments generate duplicates
       'COUNT("protocol_drafts"."id") AS "nr_of_drafts"',
       'COUNT("user_assignments"."id") AS "nr_of_assigned_users"',