FORM 4 JOINT FILER INFORMATION Names of Joint Filers: Aisling Capital III, LP Aisling Capital Partners III, LP Aisling Capital Partners III LLC Steve Elms Andrew N. Schiff, M.D. Dennis J. Purcell Address of Joint Filers: c/o Aisling Capital Partners LLC 888 Seventh Avenue New York, NY 10106 Designated Filer: Aisling Capital III, LP Issuer and Ticker Symbol: Loxo Oncology, Inc. [LOXO] Date of Event: July 12, 2018 Signatures of Joint Filers: AISLING CAPITAL III, LP By: Aisling Capital Partners III, LP General Partner By: Aisling Capital Partners III LLC General Partner By: /s/ Robert Wenzel ------------------------------------ Name: Robert Wenzel Title: CFO AISLING CAPITAL PARTNERS III, LP By: Aisling Capital Partners III LLC General Partner By: /s/ Robert Wenzel ------------------------------------ Name: Robert Wenzel Title: CFO AISLING CAPITAL PARTNERS III LLC By: /s/ Robert Wenzel ------------------------------------ Name: Robert Wenzel Title: CFO /s/ Steve Elms -------------------------------------------- Steve Elms /s/ Andrew Schiff -------------------------------------------- Andrew Schiff /s/ Dennis Purcell -------------------------------------------- Dennis Purcell