UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 6-K Report of Foreign Private Issuer Pursuant to Rule 13a-16 or 15d-16 under the Securities Exchange Act of 1934 For the month of May 2021 Commission file number: 001-39957 NLS PHARMACEUTICS LTD. (Translation of registrant's name into English) Alter Postplatz 2 CH-6370 Stans, Switzerland (Address of principal executive offices) Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F ...