Can I send a variable to paypal using paypal subscribe for development

[anuj_123]

I am trying this way but not getting custom variable in IPN response of boy

<script

    src="https://www.paypal.com/sdk/js?client-id=ClientID123&vault=true&intent=subscription"

    data-sdk-integration-source="button-factory"></script>

<script>

    paypal.Buttons({

        style: {

            shape: 'rect',

            color: 'gold',

            layout: 'vertical',

            label: 'subscribe'

        },

        createSubscription: function (data, actions) {

            return actions.subscription.create({

                'plan_id': 'P-54S50542LP608591HL7DE',

'option_selection1': "anuj-custom",

                'os4': "anuj-custom",

                 'custom_id':"anuj-custom",

                          });

        },

        onApprove: function (data, actions) {

            alert(JSON.stringify(data));

            console.log("data=" +JSON.stringify(data))

        }

    }).render('#paypal-button-container');

</script>