diff --git a/openedx_events/event_bus/avro/tests/test_avro.py b/openedx_events/event_bus/avro/tests/test_avro.py
index 2596192f..b42a39e8 100644
--- a/openedx_events/event_bus/avro/tests/test_avro.py
+++ b/openedx_events/event_bus/avro/tests/test_avro.py
@@ -98,7 +98,7 @@ def generate_test_event_data_for_data_type(data_type):  # pragma: no cover
     defaults_per_type = {
         int: 1,
         bool: True,
-        str: "passing",
+        str: "default",
         float: 1.0,
         CourseKey: CourseKey.from_string("course-v1:edX+DemoX.1+2014"),
         UsageKey: UsageKey.from_string(
diff --git a/openedx_events/event_bus/avro/tests/test_custom_serializers.py b/openedx_events/event_bus/avro/tests/test_custom_serializers.py
new file mode 100644
index 00000000..e979a942
--- /dev/null
+++ b/openedx_events/event_bus/avro/tests/test_custom_serializers.py
@@ -0,0 +1,21 @@
+from unittest import TestCase
+
+from ccx_keys.locator import CCXLocator
+
+from openedx_events.event_bus.avro.custom_serializers import (
+    CcxCourseLocatorAvroSerializer,
+)
+
+
+class TestCCXLocatorSerailizer(TestCase):
+    def test_serialize(self):
+        obj1 = CCXLocator(org="edx", course="DemoX", run="Demo_course", ccx="1")
+        expected1 = "ccx-v1:edx+DemoX+Demo_course+ccx@1"
+        result1 = CcxCourseLocatorAvroSerializer.serialize(obj1)
+        self.assertEqual(result1, expected1)
+
+    def test_deseialize(self):
+        data1 = "ccx-v1:edx+DemoX+Demo_course+ccx@1"
+        expected1 = CCXLocator(org="edx", course="DemoX", run="Demo_course", ccx="1")
+        result1 = CcxCourseLocatorAvroSerializer.deserialize(data1)
+        self.assertEqual(result1, expected1)
diff --git a/openedx_events/learning/data.py b/openedx_events/learning/data.py
index 0de3877b..83a76a60 100644
--- a/openedx_events/learning/data.py
+++ b/openedx_events/learning/data.py
@@ -535,11 +535,7 @@ class CoursePassingStatusData:
         in which the grade was updated.
     """
 
-    PASSING = 'passing'
-    FAILING = 'failing'
-    STATUSES = [PASSING, FAILING]
-
-    status = attr.ib(type=str, validator=in_(STATUSES))
+    status = attr.ib(type=str)
     course = attr.ib(type=CourseData)
     user = attr.ib(type=UserData)