Exhibit 99.1 This Statement on Form 4 is filed by the Reporting Persons listed below. Name of Designated Filer: ARTAL INTERNATIONAL S.C.A. Date of Event Requiring Statement: December 16, 2020. Issuer Name: Lexicon Pharmaceuticals, Inc. [LXRX] ARTAL INTERNATIONAL S.C.A. By: ARTAL INTERNATIONAL MANAGEMENT S.A., its general partner By: /s/ Anne Goffard ---------------- Name: Anne Goffard Title: Managing Director 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 PASCAL MINNE By: /s/ Pascal Minne ----------------