X0306 4 2019-06-11 0 0001510487 Principia Biopharma Inc. PRNB 0001131399 GLAXOSMITHKLINE PLC 980 GREAT WEST ROAD BRENTFORD MIDDLESEX X0 TW8 9GS UNITED KINGDOM 0 0 1 0 Director Stock Option 31.77 2019-06-11 4 A 0 10240 0 A 2029-06-10 Common Stock 10240 10240 I See Footnote The stock option was granted to Simeon George as director's compensation and vests and becomes exercisable in 12 equal monthly installments beginning one month after the grant date, until such time as the option is 100% vested, subject to the continuing service of Simeon George on each vesting date. As President of S. R. One, Limited and an employee of GlaxoSmithKline LLC, Simeon George is obligated to transfer any shares issued under the stock option to S.R. One, Limited, an indirect, wholly-owned subsidiary of GlaxoSmithKline plc. /s/ Victoria Whyte 2019-06-17