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  <xsd:element id="kala_StockWarrantsTextBlock" name="StockWarrantsTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="kala_DeferredTaxAssetsTaxDeferredExpenseRebatesIncentivesTradeDiscountsAndAllowances" name="DeferredTaxAssetsTaxDeferredExpenseRebatesIncentivesTradeDiscountsAndAllowances" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="kala_ScheduleOfWeightedAverageRemainingLeaseTermAndWeightedAverageDiscountRateTableTextBlock" name="ScheduleOfWeightedAverageRemainingLeaseTermAndWeightedAverageDiscountRateTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="kala_TermLoanCMember" name="TermLoanCMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="kala_NeitherTrancheBTermLoanNorTrancheCTermLoanIsMadeMember" name="NeitherTrancheBTermLoanNorTrancheCTermLoanIsMadeMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="kala_EitherTrancheBTermLoanNorTrancheCTermLoanIsMadeMember" name="EitherTrancheBTermLoanNorTrancheCTermLoanIsMadeMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="kala_DebtInstrumentPeriodicPaymentMonthlyInstallments" name="DebtInstrumentPeriodicPaymentMonthlyInstallments" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="kala_DebtInstrumentFinalPaymentFeesPercentage" name="DebtInstrumentFinalPaymentFeesPercentage" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <xsd:element id="kala_DebtInstrumentFacilityFeesPaid" name="DebtInstrumentFacilityFeesPaid" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="kala_ShareBasedCompensationArrangementByShareBasedPaymentAwardsEquityInstrumentsOtherThanOptionsNonvestedNumber" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardsEquityInstrumentsOtherThanOptionsNonvestedNumber" nillable="true" type="xbrli:positiveIntegerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <xsd:element name="CombangioIncMember" id="kala_CombangioIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FirstPatientDosedWithAnyProductInPhase2ClinicalTrialDosingMilestoneMember" id="kala_FirstPatientDosedWithAnyProductInPhase2ClinicalTrialDosingMilestoneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredEquityInterestIssuedAndIssuableNumberOfShares" id="kala_AssetAcquisitionConsiderationTransferredEquityInterestIssuedAndIssuableNumberOfShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndDeferred" id="kala_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndDeferred" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ContingentConsiderationPolicyPolicyTextBlock" id="kala_ContingentConsiderationPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SharesIssuedOnJanuary32022Member" id="kala_SharesIssuedOnJanuary32022Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PotentialMaximumPayoutForContingentConsideration" id="kala_PotentialMaximumPayoutForContingentConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PotentialPayoutForContingentConsiderationUponAchievementOfSpecifiedDevelopmentRegulatoryAndCommercialMilestones" id="kala_PotentialPayoutForContingentConsiderationUponAchievementOfSpecifiedDevelopmentRegulatoryAndCommercialMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ContingentConsiderationMember" id="kala_ContingentConsiderationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AssetAcquisitionContingentMilestoneConsiderationPayable" id="kala_AssetAcquisitionContingentMilestoneConsiderationPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ScenarioAchievementOfSalesBasedMilestoneRelatingToKpi012ProductMember" id="kala_ScenarioAchievementOfSalesBasedMilestoneRelatingToKpi012ProductMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="MeasurementInputMilestoneAchievementProbabilityMember" id="kala_MeasurementInputMilestoneAchievementProbabilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FairValueAssetsLevel1ToLevel2TransfersAmount1" id="kala_FairValueAssetsLevel1ToLevel2TransfersAmount1" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="FairValueAssetsLevel2ToLevel1TransfersAmount1" id="kala_FairValueAssetsLevel2ToLevel1TransfersAmount1" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="FairValueLiabilitiesLevel1ToLevel2TransfersAmount1" id="kala_FairValueLiabilitiesLevel1ToLevel2TransfersAmount1" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FairValueLiabilitiesLevel2ToLevel1TransfersAmount1" id="kala_FairValueLiabilitiesLevel2ToLevel1TransfersAmount1" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RepaymentsOfLongTermDebtPrincipalPayment" id="kala_RepaymentsOfLongTermDebtPrincipalPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DebtInstrumentFinalPaymentFees" id="kala_DebtInstrumentFinalPaymentFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DebtInstrumentPeriodicPaymentNumberOfInstallments" id="kala_DebtInstrumentPeriodicPaymentNumberOfInstallments" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DebtInstrumentAccretionExpenses" id="kala_DebtInstrumentAccretionExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GainLossOnFairValueReMeasurementOfContingentConsideration" id="kala_GainLossOnFairValueReMeasurementOfContingentConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SeriesENonRedeemableNonControllingPreferredStockMember" id="kala_SeriesENonRedeemableNonControllingPreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockIssuedDuringPeriodValueNonRedeemableNonControllingPreferredStockTotal" id="kala_StockIssuedDuringPeriodValueNonRedeemableNonControllingPreferredStockTotal" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IssuanceOfNonRedeemableNonControllingSeriesEPreferredStockShares" id="kala_IssuanceOfNonRedeemableNonControllingSeriesEPreferredStockShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="StockIssuedDuringPeriodValuePrivatePlacement" id="kala_StockIssuedDuringPeriodValuePrivatePlacement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodSharesPrivatePlacement" id="kala_StockIssuedDuringPeriodSharesPrivatePlacement" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AdjustedLongTermDebt" id="kala_AdjustedLongTermDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AssetAcquisitionContingentMilestoneConsiderationCashPaid" id="kala_AssetAcquisitionContingentMilestoneConsiderationCashPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AssetAcquisitionContingentMilestoneConsiderationEquityInterestIssuedOrIssuable" id="kala_AssetAcquisitionContingentMilestoneConsiderationEquityInterestIssuedOrIssuable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AssetAcquisitionContingentMilestoneConsiderationNumberOfEquityInterestIssuedOrIssuable" id="kala_AssetAcquisitionContingentMilestoneConsiderationNumberOfEquityInterestIssuedOrIssuable" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PaymentOnOrBeforeJune302023Member" id="kala_PaymentOnOrBeforeJune302023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PaymentOnOrBeforeJanuary312024Member" id="kala_PaymentOnOrBeforeJanuary312024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PaymentOnOrPriorToDecember312024Member" id="kala_PaymentOnOrPriorToDecember312024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PaymentOnOrPriorToJune302025Member" id="kala_PaymentOnOrPriorToJune302025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TaxCreditCarryforwardAmountAnnualLimitation" id="kala_TaxCreditCarryforwardAmountAnnualLimitation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SharesNotIssuedUntilEscrowReleaseDateOfMarch2023Member" id="kala_SharesNotIssuedUntilEscrowReleaseDateOfMarch2023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PaymentOCashPortionOfDosingMilestone" id="kala_PaymentOCashPortionOfDosingMilestone" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AreaOfPropertyLeased" id="kala_AreaOfPropertyLeased" type="dtr-types:areaItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RestrictedCashAndOtherLongTermAssetsMember" id="kala_RestrictedCashAndOtherLongTermAssetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorizedAnnuallyPercent" id="kala_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorizedAnnuallyPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AwardAgreementMember" id="kala_AwardAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CaliforniaInstituteForRegenerativeMedicineMember" id="kala_CaliforniaInstituteForRegenerativeMedicineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LoanAgreementWithOxfordFinanceLlcMember" id="kala_LoanAgreementWithOxfordFinanceLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AnnualLimitOnNonEmployeeDirectorCompensationForIncumbentDirectors" id="kala_AnnualLimitOnNonEmployeeDirectorCompensationForIncumbentDirectors" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AnnualLimitOnNonEmployeeDirectorCompensationForDirectorsFirstYearOfService" id="kala_AnnualLimitOnNonEmployeeDirectorCompensationForDirectorsFirstYearOfService" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AmountEntitledForInitialDisbursementOfGrant" id="kala_AmountEntitledForInitialDisbursementOfGrant" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ThresholdPeriodForAchievementOfSpecifiedMilestones" id="kala_ThresholdPeriodForAchievementOfSpecifiedMilestones" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RoyaltyOnNetSalesAsPercent" id="kala_RoyaltyOnNetSalesAsPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RoyaltyOnNetSalesBasedOnOfFundsUtilizedByCompany" id="kala_RoyaltyOnNetSalesBasedOnOfFundsUtilizedByCompany" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="TermOfRoyaltyFromDateOfFirstCommercialSaleOfSuchProductServiceOrApprovedDrug" id="kala_TermOfRoyaltyFromDateOfFirstCommercialSaleOfSuchProductServiceOrApprovedDrug" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ThresholdSalesAfterWhichRoyaltyOnNetSalesOfFundedInventionIsPayable" id="kala_ThresholdSalesAfterWhichRoyaltyOnNetSalesOfFundedInventionIsPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LondonInterbankOfferedRatesLiborMember" id="kala_LondonInterbankOfferedRatesLiborMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="GrantIncomeAbstract" id="kala_GrantIncomeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="GrantIncomeTextBlock" id="kala_GrantIncomeTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="GrantIncomeTable" id="kala_GrantIncomeTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="GrantIncomeLineItems" id="kala_GrantIncomeLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IncomeFromGrants" id="kala_IncomeFromGrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="MenloParkCaliforniaOfficeLeaseMember" id="kala_MenloParkCaliforniaOfficeLeaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SeriesFNonRedeemableNonControllingPreferredStockMember" id="kala_SeriesFNonRedeemableNonControllingPreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SecuritiesPurchaseAgreement2024Member" id="kala_SecuritiesPurchaseAgreement2024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SeriesGNonRedeemableNonControllingPreferredStockMember" id="kala_SeriesGNonRedeemableNonControllingPreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SeriesHNonRedeemableNonControllingPreferredStockMember" id="kala_SeriesHNonRedeemableNonControllingPreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ProceedsFromIssuanceOfCommonStockAndSeriesHPreferredStock" id="kala_ProceedsFromIssuanceOfCommonStockAndSeriesHPreferredStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SecondSecuritiesPurchaseAgreement2024Member" id="kala_SecondSecuritiesPurchaseAgreement2024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ScenarioAchievementOfSpecifiedDevelopmentAndRegulatoryMilestonesRelatingToKPI012ProductMember" id="kala_ScenarioAchievementOfSpecifiedDevelopmentAndRegulatoryMilestonesRelatingToKPI012ProductMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AnnualLicenseMaintenanceFeesUponAchievementOfSpecificMilestones" id="kala_AnnualLicenseMaintenanceFeesUponAchievementOfSpecificMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SeriesINonRedeemableNonControllingPreferredStockMember" id="kala_SeriesINonRedeemableNonControllingPreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ThirdSecuritiesPurchaseAgreement2024Member" id="kala_ThirdSecuritiesPurchaseAgreement2024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ProceedsFromIssuanceOfCommonStockAndSeriesIPreferredStock" id="kala_ProceedsFromIssuanceOfCommonStockAndSeriesIPreferredStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AccruedIssuanceCosts" id="kala_AccruedIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="NumberOfDaysOfObligationsDueDateOfCovenants" id="kala_NumberOfDaysOfObligationsDueDateOfCovenants" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SingleReportingSegmentMember" id="kala_SingleReportingSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResearchAndDevelopmentExpenseProductDevelopmentCosts" id="kala_ResearchAndDevelopmentExpenseProductDevelopmentCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentExpenseEmployeeRelatedCosts" id="kala_ResearchAndDevelopmentExpenseEmployeeRelatedCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ContingentConsiderationNoncurrentMember" id="kala_ContingentConsiderationNoncurrentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockIssuedDuringPeriodSharesNewIssuesConversionOfSeriesHPreferredStock" id="kala_StockIssuedDuringPeriodSharesNewIssuesConversionOfSeriesHPreferredStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodSharesNewIssuesConversionOfSeriesGPreferredStock" id="kala_StockIssuedDuringPeriodSharesNewIssuesConversionOfSeriesGPreferredStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodSharesNewIssuesSharesConversionOfSeriesGPreferredStock" id="kala_StockIssuedDuringPeriodSharesNewIssuesSharesConversionOfSeriesGPreferredStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PaymentsOfCommonStockAndPreferredIssuanceCosts" id="kala_PaymentsOfCommonStockAndPreferredIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ConvertibleLoanAgreementWithIndividualInvestorMember" id="kala_ConvertibleLoanAgreementWithIndividualInvestorMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="UnvestedRestrictedStockUnitsMember" id="kala_UnvestedRestrictedStockUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfClosings" id="kala_NumberOfClosings" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="VotingAgreementIrrevocableProxyTerm" id="kala_VotingAgreementIrrevocableProxyTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SeriesAaConvertibleNonRedeemablePreferredStockMember" id="kala_SeriesAaConvertibleNonRedeemablePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMarkToMarketAmount" id="kala_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMarkToMarketAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationTaxCreditFederalRDAndOrphanDrugCreditsAmount" id="kala_EffectiveIncomeTaxRateReconciliationTaxCreditFederalRDAndOrphanDrugCreditsAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMarkToMarketPercent" id="kala_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMarkToMarketPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationTaxCreditFederalRDAndOrphanDrugCreditsPercent" id="kala_EffectiveIncomeTaxRateReconciliationTaxCreditFederalRDAndOrphanDrugCreditsPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DeferredTaxAssetsValuationAllowanceRollForward" id="kala_DeferredTaxAssetsValuationAllowanceRollForward" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ValuationAllowanceDeferredTaxAssetIncreaseDecreaseChargedToIncomeTaxExpenseAmount" id="kala_ValuationAllowanceDeferredTaxAssetIncreaseDecreaseChargedToIncomeTaxExpenseAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SeriesAaaConvertibleNonRedeemablePreferredStockMember" id="kala_SeriesAaaConvertibleNonRedeemablePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SecuritiesPurchaseAgreementJanuary2026Member" id="kala_SecuritiesPurchaseAgreementJanuary2026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DebtInstrumentSettlementAmountOwed" id="kala_DebtInstrumentSettlementAmountOwed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PaymentsForSettlementOfDebt" id="kala_PaymentsForSettlementOfDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LoanSettlementAgreementWithOxfordFinanceLlcMember" id="kala_LoanSettlementAgreementWithOxfordFinanceLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="YounetMember" id="kala_YounetMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PlatformDevelopmentAndExclusiveLicenseAgreementMember" id="kala_PlatformDevelopmentAndExclusiveLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseAgreementInitialTerm" id="kala_LicenseAgreementInitialTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAgreementRenewalTerm" id="kala_LicenseAgreementRenewalTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAgreementMaximumCashFees" id="kala_LicenseAgreementMaximumCashFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicenseAgreementPaymentOfCashFees" id="kala_LicenseAgreementPaymentOfCashFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicenseAgreementCashFeesAmountPayable" id="kala_LicenseAgreementCashFeesAmountPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicenseAgreementCashFeesNumberOfPaymentInstallments" id="kala_LicenseAgreementCashFeesNumberOfPaymentInstallments" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="LicenseAgreementCashFeesAmountOfPaymentInstallments" id="kala_LicenseAgreementCashFeesAmountOfPaymentInstallments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicenseAgreementTerminationNoticePeriod" id="kala_LicenseAgreementTerminationNoticePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAgreementSharesAgreedToIssue" id="kala_LicenseAgreementSharesAgreedToIssue" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="LicenseAgreementShareIssuancePeriod" id="kala_LicenseAgreementShareIssuancePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAgreementCashPaymentAmountRenewalTerm" id="kala_LicenseAgreementCashPaymentAmountRenewalTerm" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicenseAgreementSharesAgreedToIssueRenewalTerm" id="kala_LicenseAgreementSharesAgreedToIssueRenewalTerm" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="LicenseAgreementShareIssuancePeriodRenewalPeriod" id="kala_LicenseAgreementShareIssuancePeriodRenewalPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAgreementMaximumDailyTradingVolumePercentage" id="kala_LicenseAgreementMaximumDailyTradingVolumePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="LicenseAgreementOptionToAcquireEquityInterestsOrAllAssetsPurchasePrice" id="kala_LicenseAgreementOptionToAcquireEquityInterestsOrAllAssetsPurchasePrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ImpairmentLongLivedAssetHeldForUseStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag" id="kala_ImpairmentLongLivedAssetHeldForUseStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SeriesAaConvertibleNonRedeemablePreferredStockAndSeriesaaaConvertibleNonRedeemablePreferredStockMember" id="kala_SeriesAaConvertibleNonRedeemablePreferredStockAndSeriesaaaConvertibleNonRedeemablePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FinancingReceivableFaceAmount" id="kala_FinancingReceivableFaceAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ProceedsFromPreferredStockReservedForFutureIssuance" id="kala_ProceedsFromPreferredStockReservedForFutureIssuance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FinancingReceivableInterestRatePercentage" id="kala_FinancingReceivableInterestRatePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="FinancingReceivableGracePeriodToMakePayment" id="kala_FinancingReceivableGracePeriodToMakePayment" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="FinancingReceivableDefaultInterestRatePercentage" id="kala_FinancingReceivableDefaultInterestRatePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="IssuanceOfStockAndWarrantsForSettlementAgreements" id="kala_IssuanceOfStockAndWarrantsForSettlementAgreements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
</xsd:schema>
