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      <link:linkbaseRef xlink:type="simple" xlink:href="mdgl-20171231_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="mdgl-20171231_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="mdgl-20171231_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
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  <xsd:import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/dei/2014-01-31" schemaLocation="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd" />
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  <xsd:element name="CorporateDebtSecuritiesDueWithinThreeMonthsMember" id="mdgl_CorporateDebtSecuritiesDueWithinThreeMonthsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="HoffmanLaRocheMember" id="mdgl_HoffmanLaRocheMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DocumentAndEntityInformationAbstract" id="mdgl_DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ScheduleOfShareBasedCompensationExpenseAllocationOfCompensationCostsAndRecognizedPeriodCostsTableTextBlock" id="mdgl_ScheduleOfShareBasedCompensationExpenseAllocationOfCompensationCostsAndRecognizedPeriodCostsTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="MaturityPeriodFromDateOfPurchaseToClassifyInvestmentAsMarketableSecurities" id="mdgl_MaturityPeriodFromDateOfPurchaseToClassifyInvestmentAsMarketableSecurities" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CashAndCashEquivalentsAndAvailableForSaleSecuritiesGrossUnrealizedGains" id="mdgl_CashAndCashEquivalentsAndAvailableForSaleSecuritiesGrossUnrealizedGains" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="CashAndCashEquivalentsAndAvailableForSaleSecuritiesGrossUnrealizedLosses" id="mdgl_CashAndCashEquivalentsAndAvailableForSaleSecuritiesGrossUnrealizedLosses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <element id="mdgl_CommonStockAggregateOfferingPrice" name="CommonStockAggregateOfferingPrice" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <xsd:element name="PercentageOfGrossProceedsPayableAsCommission" id="mdgl_PercentageOfGrossProceedsPayableAsCommission" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualLifeAbstract" id="mdgl_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualLifeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAggregateIntrinsicValueAbstract" id="mdgl_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAggregateIntrinsicValueAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <element id="mdgl_CommonStockVotingRightsNumber" name="CommonStockVotingRightsNumber" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <xsd:element name="AtTheMarketIssuanceSalesAgreementMember" id="mdgl_AtTheMarketIssuanceSalesAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EmployeeAndDirectorsStockOptionsMember" id="mdgl_EmployeeAndDirectorsStockOptionsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <element id="mdgl_CowenCo.LlcMember" name="CowenCo.LlcMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_SalesAgreementTerminationNoticePeriodDays" name="SalesAgreementTerminationNoticePeriodDays" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_MadrigalPharmaceuticalsIncMember" name="MadrigalPharmaceuticalsIncMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_PaidInKindInterestRelatedPartyDebt" name="PaidInKindInterestRelatedPartyDebt" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_IncreaseDecreaseInAccruedInterestRelatedParty" name="IncreaseDecreaseInAccruedInterestRelatedParty" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_RestructuringOfRelatedPartyDebt" name="RestructuringOfRelatedPartyDebt" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_LiquidityAndUncertaintiesDisclosureAbstract" name="LiquidityAndUncertaintiesDisclosureAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_PatentCosts" name="PatentCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_DeferredTaxAssetsPercentageOfValuationAllowance" name="DeferredTaxAssetsPercentageOfValuationAllowance" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_AdvancesPayableToRelatedPartiesDisclosureAbstract" name="AdvancesPayableToRelatedPartiesDisclosureAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_AdvancesPayableToRelatedPartiesDisclosureTextBlock" name="AdvancesPayableToRelatedPartiesDisclosureTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ProceedsFromAdvancesFromRelatedParties" name="ProceedsFromAdvancesFromRelatedParties" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ChangeInControlBonusPlanMember" name="ChangeInControlBonusPlanMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_MergerCombinedCompanyMember" name="MergerCombinedCompanyMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayableAccruedExpensesAndOtherLiabilities" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayableAccruedExpensesAndOtherLiabilities" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_FormerChiefExecutiveOfficerMember" name="FormerChiefExecutiveOfficerMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ConsultingAgreementMember" name="ConsultingAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_RelatedPartyTransactionPeriodOfPriorNoticeForTerminationOfAgreement" name="RelatedPartyTransactionPeriodOfPriorNoticeForTerminationOfAgreement" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ResearchDevelopmentAndCommercializationAgreementMember" name="ResearchDevelopmentAndCommercializationAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_RemainingMilestonePayments" name="RemainingMilestonePayments" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ConvertiblePromissoryNotesRelatedPartiesDisclosureAbstract" name="ConvertiblePromissoryNotesRelatedPartiesDisclosureAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ConvertiblePromissoryNotesRelatedPartiesDisclosureTextBlock" name="ConvertiblePromissoryNotesRelatedPartiesDisclosureTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_AmendedAndRestatedMarch12016ConvertiblePromissoryNotesPayableMember" name="AmendedAndRestatedMarch12016ConvertiblePromissoryNotesPayableMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_LenderDMember" name="LenderDMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_InterestPayableAndWaivedInterestRelatedPartyCurrent" name="InterestPayableAndWaivedInterestRelatedPartyCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_InterestPayableRelatedPartyCurrent" name="InterestPayableRelatedPartyCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_InterestPayableWaivedRelatedPartyCurrent" name="InterestPayableWaivedRelatedPartyCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_RelatedPartyTransactionsDebtConversionConvertedInstrumentAmount" name="RelatedPartyTransactionsDebtConversionConvertedInstrumentAmount" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_NumberOfSharesIssuedForEachShareOfAcquiredEntity" name="NumberOfSharesIssuedForEachShareOfAcquiredEntity" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_SyntaPharmaceuticalsCorpMember" name="SyntaPharmaceuticalsCorpMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_StockholdersMember" name="StockholdersMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_BusinessCombinationChangeControlSharesReceivedByPlanParticipantsInBonusOrShareBasedCompensationPlan" name="BusinessCombinationChangeControlSharesReceivedByPlanParticipantsInBonusOrShareBasedCompensationPlan" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_BonusPlanAwardsPercentageOfAwardsReceivedToEntitysShares" name="BonusPlanAwardsPercentageOfAwardsReceivedToEntitysShares" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ReverseMergerAgreementAbstract" name="ReverseMergerAgreementAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_AdjustmentsToAdditionalPaidInCapitalRelatedPartyDebtRestructuring" name="AdjustmentsToAdditionalPaidInCapitalRelatedPartyDebtRestructuring" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_AdjustmentOfCommonStockSharesRelatedToConversionOfConvertibleDebt" name="AdjustmentOfCommonStockSharesRelatedToConversionOfConvertibleDebt" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_RemainingSecuritiesUnderShelfRegistrationValue" name="RemainingSecuritiesUnderShelfRegistrationValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_OtherShareBasedCompensation" name="OtherShareBasedCompensation" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ProceedsFromSaleOfPropertyPlantAndEquipmentAndOtherAssets" name="ProceedsFromSaleOfPropertyPlantAndEquipmentAndOtherAssets" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost" name="DeferredTaxLiabilitiesTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_DeferredTaxAssetsDeferredExpenseCapitalizedResearchAndDevelopmentCosts" name="DeferredTaxAssetsDeferredExpenseCapitalizedResearchAndDevelopmentCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseInterestExpensesAmount" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseInterestExpensesAmount" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_EffectiveIncomeTaxRateReconciliationTransactionCostsAmount" name="EffectiveIncomeTaxRateReconciliationTransactionCostsAmount" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentGoodwill" name="BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentGoodwill" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_RecapitalizationDisclosureAbstract" name="RecapitalizationDisclosureAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_RecapitalizationTextBlock" name="RecapitalizationTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_SecuritiesPurchaseAgreementMember" name="SecuritiesPurchaseAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ConvertibleSeriesPreferredStockMember" name="ConvertibleSeriesPreferredStockMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_CashCashEquivalentsAndShortTermInvestmentsAtCost" name="CashCashEquivalentsAndShortTermInvestmentsAtCost" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ProceedsFromIssuanceOrSaleOfEquityNet" name="ProceedsFromIssuanceOrSaleOfEquityNet" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_RelatedPartyLenderExchangedAdvancesToConvertibleDebtNumber" name="RelatedPartyLenderExchangedAdvancesToConvertibleDebtNumber" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_PreferredStockNumberOfVotingRights" name="PreferredStockNumberOfVotingRights" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_TaxCutsAndJobsActOf2017ChangeInTaxRateDeferredTaxAssetIncomeTaxExpense" name="TaxCutsAndJobsActOf2017ChangeInTaxRateDeferredTaxAssetIncomeTaxExpense" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_GoldmanSachsCoMember" name="GoldmanSachsCoMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit" name="TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_UnderwritingAgreementMember" name="UnderwritingAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_RegisteredOfferingMember" name="RegisteredOfferingMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_SaleOfStockPeriodGrantedToPurchaseAdditionalShares" name="SaleOfStockPeriodGrantedToPurchaseAdditionalShares" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="mdgl_ConvertibleNotesRelatedPartyInterestPayableRecordedAsIncreaseInAdditionalPaidInCapital" name="ConvertibleNotesRelatedPartyInterestPayableRecordedAsIncreaseInAdditionalPaidInCapital" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
</xsd:schema>
