I'm not quite sure what you mean? Sikhism, Jainism, and Buddhism (Dharmic religions) have been practiced since their creation, and are still practices by many hundreds of thousands of people to the present day.

Indo-European typically refers to linguistic categories, rather than religious ones, but wouldn't the Abrahamic religions and Zoroastrianism fall in to the category of Indo-European, all being conceived in the lands between Europe and India?