<?xml version="1.0"?>
<ownershipDocument>

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    <periodOfReport>2021-02-22</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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        <issuerName>Moderna, Inc.</issuerName>
        <issuerTradingSymbol>MRNA</issuerTradingSymbol>
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            <rptOwnerName>AFEYAN NOUBAR</rptOwnerName>
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            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02142</rptOwnerZipCode>
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            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>102852</value>
                    <footnoteId id="F19"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>140.236</value>
                    <footnoteId id="F19"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17233161</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>70631</value>
                    <footnoteId id="F20"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>141.4573</value>
                    <footnoteId id="F20"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17162530</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>117011</value>
                    <footnoteId id="F21"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>142.7605</value>
                    <footnoteId id="F21"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17045519</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>397126</value>
                    <footnoteId id="F22"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>143.5744</value>
                    <footnoteId id="F22"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>16648393</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>405551</value>
                    <footnoteId id="F23"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>144.5529</value>
                    <footnoteId id="F23"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>16242842</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>357316</value>
                    <footnoteId id="F24"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>145.4803</value>
                    <footnoteId id="F24"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15885526</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>307795</value>
                    <footnoteId id="F25"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>146.6369</value>
                    <footnoteId id="F25"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15577731</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>292483</value>
                    <footnoteId id="F26"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>147.5729</value>
                    <footnoteId id="F26"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15285248</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>268688</value>
                    <footnoteId id="F27"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>148.521</value>
                    <footnoteId id="F27"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15016560</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>179268</value>
                    <footnoteId id="F28"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>149.626</value>
                    <footnoteId id="F28"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14837292</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>190710</value>
                    <footnoteId id="F29"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>150.5137</value>
                    <footnoteId id="F29"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14646582</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>23423</value>
                    <footnoteId id="F30"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>151.2851</value>
                    <footnoteId id="F30"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14623159</value>
                    <footnoteId id="F31"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship Ventures Fund IV, L.P. and Flagship Ventures Fund IV-Rx, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11464359</value>
                    <footnoteId id="F32"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Flagship VentureLabs IV LLC and Flagship Pioneering, Inc.</value>
                    <footnoteId id="F32"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2101703</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These sales were effected by Flagship Ventures Fund IV, L.P. (&quot;Flagship Fund IV&quot;) and Flagship Ventures Fund IV-Rx, L.P. (&quot;Flagship Fund IV-Rx&quot;) pursuant to Rule 10b5-1 trading plans adopted on December 23, 2020.</footnote>
        <footnote id="F2">Represents 135,986 shares sold by Flagship Fund IV and 25,901 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $158.65 to $159.61, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F3">Shares held directly by Flagship Fund IV and Flagship Fund IV-Rx. Flagship Ventures Fund IV General Partner LLC (&quot;Flagship Fund IV GP&quot;) is the general partner of each of Flagship Fund IV and Flagship Fund IV-Rx. The reporting person is the sole manager of Flagship Fund IV GP and disclaims beneficial ownership of such shares except to the extent of his pecuniary interest therein.</footnote>
        <footnote id="F4">Represents 45,703 shares sold by Flagship Fund IV and 8,706 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $159.65 to $160.64, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F5">Represents 25,879 shares sold by Flagship Fund IV and 4,929 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $160.65 to $161.54, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F6">Represents 210,421 shares sold by Flagship Fund IV and 40,080 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $161.79 to $162.78, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F7">Represents 307,835 shares sold by Flagship Fund IV and 58,636 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $162.79 to $163.78, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F8">Represents 158,928 shares sold by Flagship Fund IV and 30,272 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $163.79 to $164.78, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F9">Represents 139,086 shares sold by Flagship Fund IV and 26,492 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $164.79 to $165.78, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F10">Represents 295,016 shares sold by Flagship Fund IV and 56,194 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $165.79 to $166.78, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F11">Represents 103,081 shares sold by Flagship Fund IV and 19,634 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $166.79 to $167.78, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F12">Represents 49,037 shares sold by Flagship Fund IV and 9,340 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $167.79 to $168.75, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F13">Represents 45,589 shares sold by Flagship Fund IV and 8,685 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $168.80 to $169.79, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F14">Represents 25,989 shares sold by Flagship Fund IV and 4,949 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $169.85 to $170.35, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F15">Represents 8,387 shares sold by Flagship Fund IV and 1,598 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $136.01 to $137.00, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F16">Represents 102,600 shares sold by Flagship Fund IV and 19,542 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $137.01 to $137.96, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F17">Represents 38,826 shares sold by Flagship Fund IV and 7,396 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $138.03 to $139.01, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F18">Represents 47,406 shares sold by Flagship Fund IV and 9,029 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $139.05 to $140.04, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F19">Represents 86,395 shares sold by Flagship Fund IV and 16,457 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $140.05 to $140.92, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F20">Represents 59,330 shares sold by Flagship Fund IV and 11,301 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $141.06 to $142.05, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F21">Represents 98,290 shares sold by Flagship Fund IV and 18,721 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $142.06 to $143.05, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F22">Represents 333,586 shares sold by Flagship Fund IV and 63,540 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $143.06 to $144.05, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F23">Represents 340,662 shares sold by Flagship Fund IV and 64,889 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $144.06 to $145.05, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F24">Represents 300,146 shares sold by Flagship Fund IV and 57,170 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $145.06 to $146.05, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F25">Represents 258,547 shares sold by Flagship Fund IV and 49,248 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $146.07 to $147.06, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F26">Represents 245,686 shares sold by Flagship Fund IV and 46,797 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $147.07 to $148.06, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F27">Represents 225,698 shares sold by Flagship Fund IV and 42,990 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $148.07 to $149.06, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F28">Represents 150,585 shares sold by Flagship Fund IV and 28,683 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $149.07 to $150.06, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F29">Represents 160,196 shares sold by Flagship Fund IV and 30,514 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $150.08 to $151.07, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F30">Represents 19,676 shares sold by Flagship Fund IV and 3,747 shares sold by Flagship Fund IV-Rx. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $151.08 to $151.64, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F31">Following the transactions reported herein, 10,417,023 shares are held directly by Flagship Fund IV and 4,206,136 shares are held directly by Flagship Fund IV-Rx.</footnote>
        <footnote id="F32">11,460,435 shares are held directly by Flagship VentureLabs IV LLC (&quot;VentureLabs IV&quot;) and 3,924 shares are held directly by Flagship Pioneering, Inc. (&quot;Flagship Pioneering&quot;). Flagship Fund IV is a member of VentureLabs IV and also serves as its manager. Flagship Fund IV GP is the general partner of Flagship Fund IV. The reporting person is the sole manager of Flagship Fund IV GP and CEO and sole stockholder of Flagship Pioneering and disclaims beneficial ownership of such shares except to the extent of his pecuniary interest therein.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Noubar B. Afeyan, Ph.D. By: /s/ Noubar B. Afeyan, Ph.D.</signatureName>
        <signatureDate>2021-02-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
