Exhibit 99.1 This Statement on Form 4 is filed by the Reporting Persons listed below. Name of Designated Filer: INVUS PUBLIC EQUITIES, L.P. Date of Event Requiring Statement: November 15, 2017. Issuer Name: Lexicon Pharmaceuticals, Inc. [LXRX] INVUS PUBLIC EQUITIES, L.P. By: Invus Public Equities Advisors, LLC, its general partner By: /s/ Raymond Debbane ------------------------------------------------- Name: Raymond Debbane Title: President ARTAL INTERNATIONAL S.C.A. By: Artal International Management S.A., its managing partner By: /s/ Anne Goffard ------------------------------------------------- Name: Anne Goffard Title: Managing Director INVUS, L.P. By: Invus Advisors, L.L.C., its general partner By: /s/ Raymond Debbane ------------------------------------------------- Name: Raymond Debbane Title: President INVUS ADVISORS, L.L.C. By: /s/ Raymond Debbane ------------------------------------------------- Name: Raymond Debbane Title: President INVUS PUBLIC EQUITIES ADVISORS, LLC By: /s/ Raymond Debbane ------------------------------------------------- Name: Raymond Debbane Title: President ARTAL INTERNATIONAL MANAGEMENT S.A. By: /s/ Anne Goffard ------------------------------------------------- Name: Anne Goffard Title: Managing Director ARTAL GROUP S.A. By: /s/ Anne Goffard ------------------------------------------------- Name: Anne Goffard Title: Authorized Person WESTEND S.A. By: /s/ Pascal Minne ------------------------------------------------- Name: Pascal Minne Title: Director STICHTING ADMINISTRATIEKANTOOR WESTEND By: /s/ Pascal Minne ------------------------------------------------- Name: Pascal Minne Title: Sole Member of the Board MR. PASCAL MINNE By: /s/ Pascal Minne -------------------------------------------------