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    <footnotes>
        <footnote id="F1">Shares withheld by Neurocrine Biosciences, Inc. (the &quot;Company&quot; or &quot;Issuer&quot;) to satisfy tax withholding requirements on vesting of restricted stock units (&quot;RSUs&quot;) or performance restricted stock units (&quot;PRSUs&quot;), as applicable. No shares were sold.</footnote>
        <footnote id="F2">On May 19, 2023, the Reporting Person was granted PRSUs representing the right to receive shares of the Issuer's common stock based upon the achievement of specified performance metrics over the three-year performance period ending on December 31, 2025. Effective February 13, 2026, the achievement of the applicable performance metrics and the resulting payout level were certified, and, as a result of such certification, the PRSUs vested at 125% of the target number of shares subject to the award.</footnote>
        <footnote id="F3">Each RSU represents a contingent right to receive one share of the Issuer's common stock.</footnote>
        <footnote id="F4">This RSU was granted to the Reporting Person on February 12, 2025. In accordance with the terms of the RSU, the award vested as to 2,133 shares on February 12, 2026, and will vest as to 2,133 shares on February 12, 2027, 2,134 shares on February 12, 2028, and 2,134 shares on February 12, 2029, subject to the terms and conditions of the award.</footnote>
        <footnote id="F5">This RSU was granted to the Reporting Person on February 13, 2024.  In accordance with the terms of the RSU, the award vested as to 2,241 shares on February 13, 2025, vested as to 2,241 shares on February 13, 2026, and will vest as to 2,242 shares on February 13, 2027, and 2,242 shares on February 13, 2028, subject to the terms and conditions of the award.</footnote>
        <footnote id="F6">This RSU was granted to the Reporting Person on February 13, 2023.  In accordance with the terms of the RSU, the award vested as to 2,566 shares on February 13, 2024, vested as to 2,566 shares on February 13, 2025, vested as to 2,566 shares on February 13, 2026, and will vest as to 2,566 shares on February 13, 2027, subject to the terms and conditions of the award.</footnote>
        <footnote id="F7">Represents option of which 1/48th of the shares underlying the option becomes vested and exercisable on March 13, 2026 and an additional 1/48th of the shares underlying the option becomes vested and exercisable each month thereafter.</footnote>
        <footnote id="F8">The Restricted Stock Units will vest annually at 1/4 of the units vesting on each of February 13, 2027, February 13, 2028, February 13, 2029, and February 13, 2030.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Darin Lippoldt, Attorney-in-Fact</signatureName>
        <signatureDate>2026-02-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
