diff --git a/sessionctx/binloginfo/binloginfo_test.go b/sessionctx/binloginfo/binloginfo_test.go
index 72f255ad70d42..89622fe6c226c 100644
--- a/sessionctx/binloginfo/binloginfo_test.go
+++ b/sessionctx/binloginfo/binloginfo_test.go
@@ -619,8 +619,12 @@ func (s *testBinlogSuite) TestAddSpecialComment(c *C) {
 			"create table t1(id int, v int, primary key(a) /*T![clustered_index] clustered */ );",
 		},
 		{
-			"create table t1(id int primary key clustered, v int);", // CDC upstream => downstream never produce this
 			"create table t1(id int primary key clustered, v int);",
+			"create table t1(id int primary key /*T![clustered_index] clustered */ , v int);",
+		},
+		{
+			"alter table t add primary key(a) clustered;",
+			"alter table t add primary key(a) /*T![clustered_index] clustered */ ;",
 		},
 		{
 			"create table t1 (id int, a varchar(255), primary key (a, b) nonclustered);",
diff --git a/types/parser_driver/special_cmt_ctrl.go b/types/parser_driver/special_cmt_ctrl.go
index 748bbffc5ec0d..ffa26636981c5 100644
--- a/types/parser_driver/special_cmt_ctrl.go
+++ b/types/parser_driver/special_cmt_ctrl.go
@@ -68,5 +68,5 @@ var FeatureIDPatterns = map[featureID]*regexp.Regexp{
 	FeatureIDAutoRandom:     regexp.MustCompile(`(?P<REPLACE>(?i)AUTO_RANDOM\b\s*(\s*\(\s*\d+\s*\)\s*)?)`),
 	FeatureIDAutoIDCache:    regexp.MustCompile(`(?P<REPLACE>(?i)AUTO_ID_CACHE\s*=?\s*\d+\s*)`),
 	FeatureIDAutoRandomBase: regexp.MustCompile(`(?P<REPLACE>(?i)AUTO_RANDOM_BASE\s*=?\s*\d+\s*)`),
-	FeatureClusteredIndex:   regexp.MustCompile(`(?i)PRIMARY\s+KEY\s*\(.*\)\s+(?P<REPLACE>(NON)?CLUSTERED\b)`),
+	FeatureClusteredIndex:   regexp.MustCompile(`(?i)PRIMARY\s+KEY(\s*\(.*\))?\s+(?P<REPLACE>(NON)?CLUSTERED\b)`),
 }