JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.16.4/lodash.min.js.map"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.16.4/lodash.min.js"></script>

JavaScript

var tst = [
 {"topicId":1,"subTopicId":1,"topicName":"a","subTopicName1":"w"},
 {"topicId":2,"subTopicId":2,"topicName":"b","subTopicName2":"x"},
 {"topicId":3,"subTopicId":3,"topicName":"c","subTopicName3":"y"},
 {"topicId":1,"subTopicId":4,"topicName":"c","subTopicName4":"z"}
];

var t = _.uniqBy(tst, 'topicId');
var dataMap = {
    topicId: 'id',
    topicName: 'name'
};


var finalT = t.map(function (topic) {
    var t = {};
    for (var key in dataMap) {
        t[dataMap[key]] = topic[key];
    };
    return t;
});

console.log(finalT);