diff --git a/mod/assign/feedback/editpdf/classes/document_services.php b/mod/assign/feedback/editpdf/classes/document_services.php
index 7ae0b30ef02..912bd8addff 100644
--- a/mod/assign/feedback/editpdf/classes/document_services.php
+++ b/mod/assign/feedback/editpdf/classes/document_services.php
@@ -438,8 +438,10 @@ class document_services {
         if (!empty($files)) {
             $first = reset($files);
             if (!$readonly && $first->get_timemodified() < $submission->timemodified) {
-                // Image files are stale - regenerate them, except in readonly mode.
+                // Image files are stale, we need to regenerate them, except in readonly mode.
+                // We also need to remove the draft annotations and comments associated with this attempt.
                 $fs->delete_area_files($contextid, $component, $filearea, $itemid);
+                page_editor::delete_draft_content($itemid);
                 $files = array();
             } else {
 
diff --git a/mod/assign/feedback/editpdf/classes/page_editor.php b/mod/assign/feedback/editpdf/classes/page_editor.php
index 1b1447ac0df..3dfa0716871 100644
--- a/mod/assign/feedback/editpdf/classes/page_editor.php
+++ b/mod/assign/feedback/editpdf/classes/page_editor.php
@@ -340,4 +340,21 @@ class page_editor {
 
         return true;
     }
+
+    /**
+     * Delete the draft annotations and comments.
+     *
+     * This is intended to be used when the version of the PDF has changed and the annotations
+     * might not be relevant any more, therefore we should delete them.
+     *
+     * @param int $gradeid The grade ID.
+     * @return bool
+     */
+    public static function delete_draft_content($gradeid) {
+        global $DB;
+        $conditions = array('gradeid' => $gradeid, 'draft' => 1);
+        $result = $DB->delete_records('assignfeedback_editpdf_annot', $conditions);
+        $result = $result && $DB->delete_records('assignfeedback_editpdf_cmnt', $conditions);
+        return $result;
+    }
 }