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
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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
    ----------------