The First International Nikolai Karlovich Medtner Competition will be held at the end of November 2016 in St Petersburg, organised by Nota Bene Association. The competition is open for pianists, vocalists and musicological research and review in English or Russian language. Applications are accepted until 15 October. The submission guidelines can be found here; they didn’t announce them in translation for whatever reason, but I was told that contributions in English are welcome.
Update November 2016: The competition’s musicological research and review section was cancelled due to an insufficient number of contributions. This fact was communicated only upon request.