X0306 4 2020-08-20 0 0001802665 Harmony Biosciences Holdings, Inc. HRMY 0001602402 Nielsen Jack C/O 630 W. GERMANTOWN PIKE, SUITE 215 PLYMOUTH MEETING PA 19462 1 0 0 0 Common Stock 2020-08-20 4 P 0 2736 35.00 A 2736 I See Footnote Common Stock 2020-08-21 4 P 0 24812 24.00 A 27548 I See Footnote Common Stock 2020-08-21 4 P 0 7352 34.10 A 34900 I See Footnote Common Stock 2020-08-24 4 P 0 3057 34.30 A 37957 I See Footnote The shares are held of record by Vivo Capital Fund IX, L.P. Vivo Capital IX, LLC is the General Partner of Vivo Capital Fund IX, L.P. As a managing member of Vivo Capital IX, LLC, Jack Nielsen shares voting and dispositive power with respect to the shares held of record by Vivo Capital Fund IX, L.P with other managing members, but disclaims beneficial ownership of such shares except to the extent of his individual pecuniary interest therein. The price reported herein is the public offering price. The price reported herein is a weighted average price. These shares were acquired on the open market in multiple transactions at prices ranging from $33.3 to $35.0, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares acquired at each separate price within the ranges set forth in footnote (3) to this Form 4. The price reported herein is a weighted average price. These shares were acquired on the open market in multiple transactions at prices ranging from $35.0 to $33.8, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares acquired at each separate price within the ranges set forth in footnote (4) to this Form 4. /s/ Stephanie Wisdo, Attorney-in-fact for Jack Bech Nielsen 2020-08-24