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<!-- Creation Date :2023-05-03T20:40:15.3208+00:00 -->
<!-- Copyright (c) 2023 Donnelly Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="algs_LuxnaLicenseAgreementMember" name="LuxnaLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_MerckLicenseAndResearchCollaborationFirstAmendmentMember" name="MerckLicenseAndResearchCollaborationFirstAmendmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_MerckLicenseAndResearchCollaborationMember" name="MerckLicenseAndResearchCollaborationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_MerckMember" name="MerckMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_NonVotingCommonStocksMember" name="NonVotingCommonStocksMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_SAntigenTransportInhibitingOligonucleotidePolymersMember" name="SAntigenTransportInhibitingOligonucleotidePolymersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_SeriesBTwoPreferredStockMember" name="SeriesBTwoPreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_VotingCommonStocksMember" name="VotingCommonStocksMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_DeferredOfferingCostsPolicyTextBlock" name="DeferredOfferingCostsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_RecentlyIssuedAccountingPronouncementsNotYetAdoptedPolicyTextBlock" name="RecentlyIssuedAccountingPronouncementsNotYetAdoptedPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_RiskAndUncertainityPolicyTextBlock" name="RiskAndUncertainityPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_UnauditedInterimFinancialInformationPolicyTextBlock" name="UnauditedInterimFinancialInformationPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_DerivativeLiabilitiesAndRedeemableConvertiblePreferredStockLiabilityTable" name="DerivativeLiabilitiesAndRedeemableConvertiblePreferredStockLiabilityTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_InvestmentInAvailableForSaleAndHeldToMaturitySecuritiesTable" name="InvestmentInAvailableForSaleAndHeldToMaturitySecuritiesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_NatureOfOperationsTable" name="NatureOfOperationsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_ScheduleOfAvailableForSaleAndHeldToMaturitySecuritiesAmortisedCostGrossUnrealisedGainsLossesAndFairValueTable" name="ScheduleOfAvailableForSaleAndHeldToMaturitySecuritiesAmortisedCostGrossUnrealisedGainsLossesAndFairValueTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="algs_DebtSecuritiesAvailableForSaleMaturityTableTextBlock" name="DebtSecuritiesAvailableForSaleMaturityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_ScheduleOfAdditionalInformationRelatedToTheLeasesTableTextBlock" name="ScheduleOfAdditionalInformationRelatedToTheLeasesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_ScheduleOfEstimatedUsefulLifeOfAssetTableTextBlock" name="ScheduleOfEstimatedUsefulLifeOfAssetTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_SummaryOfAvailableForSaleAndHeldToMaturitySecuritiesAmortizedCostGrossUnrealizedGainsLossesAndFairValueTableTextBlock" name="SummaryOfAvailableForSaleAndHeldToMaturitySecuritiesAmortizedCostGrossUnrealizedGainsLossesAndFairValueTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_DerivativeLiabilitiesAndRedeemableConvertiblePreferredStockLiabilityTextBlock" name="DerivativeLiabilitiesAndRedeemableConvertiblePreferredStockLiabilityTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_DisclosureOfDeferredRevenueFromCollaborationsTableTextBlock" name="DisclosureOfDeferredRevenueFromCollaborationsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_DisclosureOfDeferredRevenueFromCustomersTableTextBlock" name="DisclosureOfDeferredRevenueFromCustomersTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_DiscontinuedDevelopmentOfDrugCandidatesTextBlock" name="DiscontinuedDevelopmentOfDrugCandidatesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_LicenseAndCollaborationAgreementsTextBlock" name="LicenseAndCollaborationAgreementsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="algs_SignificantAccountingPoliciesAndEstimatesPolicyTextBlock" name="SignificantAccountingPoliciesAndEstimatesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
