<?xml version="1.0" encoding="us-ascii"?>
<!--Generated by EDGARfilings PROfile 4.3.0.0 Summit Financial Printing, LLC. All rights reserved.-->
<xs:schema targetNamespace="http://cytrx.com/20170630" elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:cytr="http://cytrx.com/20170630" xmlns:us-types="http://fasb.org/us-types/2016-01-31" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:invest="http://xbrl.sec.gov/invest/2013-01-31" xmlns:num="http://www.xbrl.org/dtr/type/numeric" xmlns:nonnum="http://www.xbrl.org/dtr/type/non-numeric" xmlns:dei="http://xbrl.sec.gov/dei/2014-01-31">
  <xs:annotation>
    <xs:appinfo>
      <link:linkbaseRef xlink:type="simple" xlink:href="cytr-20170630_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="cytr-20170630_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="cytr-20170630_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="cytr-20170630_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:roleType roleURI="http://cytrx.com/role/DocumentAndEntityInformation" id="DocumentAndEntityInformation">
        <link:definition>000100 - Document - Document and Entity Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/CondensedBalanceSheetsUnaudited" id="CondensedBalanceSheetsUnaudited">
        <link:definition>010000 - Statement - CONDENSED BALANCE SHEETS (Unaudited)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/CondensedBalanceSheetsUnauditedParenthetical" id="CondensedBalanceSheetsUnauditedParenthetical">
        <!--Parent Role: CONDENSED BALANCE SHEETS (Unaudited)-->
        <link:definition>010100 - Statement - CONDENSED BALANCE SHEETS (Unaudited) (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/CondensedStatementsOfOperationsUnaudited" id="CondensedStatementsOfOperationsUnaudited">
        <link:definition>020000 - Statement - CONDENSED STATEMENTS OF OPERATIONS (Unaudited)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/CondensedStatementsOfCashFlowsUnaudited" id="CondensedStatementsOfCashFlowsUnaudited">
        <link:definition>030000 - Statement - CONDENSED STATEMENTS OF CASH FLOWS (Unaudited)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/DescriptionOfCompanyAndBasisOfPresentation" id="DescriptionOfCompanyAndBasisOfPresentation">
        <link:definition>060100 - Disclosure - Description of Company and Basis of Presentation</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/ForeignCurrencyRemeasurement" id="ForeignCurrencyRemeasurement">
        <link:definition>060200 - Disclosure - Foreign Currency Remeasurement</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/RecentAccountingPronouncements" id="RecentAccountingPronouncements">
        <link:definition>060300 - Disclosure - Recent Accounting Pronouncements</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/TermLoan" id="TermLoan">
        <link:definition>060400 - Disclosure - Term Loan</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/BasicAndDilutedNetLossPerCommonShare" id="BasicAndDilutedNetLossPerCommonShare">
        <link:definition>060500 - Disclosure - Basic and Diluted Net Loss Per Common Share</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/WarrantLiabilities" id="WarrantLiabilities">
        <link:definition>060600 - Disclosure - Warrant Liabilities</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/StockBasedCompensation" id="StockBasedCompensation">
        <link:definition>060700 - Disclosure - Stock Based Compensation</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/FairValueMeasurements" id="FairValueMeasurements">
        <link:definition>060800 - Disclosure - Fair Value Measurements</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/LiquidityAndCapitalResources" id="LiquidityAndCapitalResources">
        <link:definition>060900 - Disclosure - Liquidity and Capital Resources</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/EquityTransactions" id="EquityTransactions">
        <link:definition>061000 - Disclosure - Equity Transactions</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/IncomeTaxes" id="IncomeTaxes">
        <link:definition>061100 - Disclosure - Income Taxes</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/CommitmentsAndContingencies" id="CommitmentsAndContingencies">
        <link:definition>061200 - Disclosure - Commitments and contingencies</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/SubsequentEvents" id="SubsequentEvents">
        <link:definition>061300 - Disclosure - Subsequent Events</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/TermLoanTables" id="TermLoanTables">
        <!--Parent Role: Term Loan-->
        <link:definition>080400 - Disclosure - Term Loan (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/WarrantLiabilitiesTables" id="WarrantLiabilitiesTables">
        <!--Parent Role: Warrant Liabilities-->
        <link:definition>080600 - Disclosure - Warrant Liabilities (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/StockBasedCompensationTables" id="StockBasedCompensationTables">
        <!--Parent Role: Stock Based Compensation-->
        <link:definition>080700 - Disclosure - Stock Based Compensation (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/FairValueMeasurementsTables" id="FairValueMeasurementsTables">
        <!--Parent Role: Fair Value Measurements-->
        <link:definition>080800 - Disclosure - Fair Value Measurements (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/DescriptionOfCompanyAndBasisOfPresentationDetails" id="DescriptionOfCompanyAndBasisOfPresentationDetails">
        <!--Parent Role: Description of Company and Basis of Presentation-->
        <link:definition>090100 - Disclosure - Description of Company and Basis of Presentation (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/ForeignCurrencyRemeasurementDetails" id="ForeignCurrencyRemeasurementDetails">
        <!--Parent Role: Foreign Currency Remeasurement-->
        <link:definition>090200 - Disclosure - Foreign Currency Remeasurement (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/TermLoanDetails" id="TermLoanDetails">
        <!--Parent Role: Term Loan-->
        <link:definition>090400 - Disclosure - Term Loan (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/BasicAndDilutedNetLossPerCommonShareDetails" id="BasicAndDilutedNetLossPerCommonShareDetails">
        <!--Parent Role: Basic and Diluted Net Loss Per Common Share-->
        <link:definition>090500 - Disclosure - Basic and Diluted Net Loss Per Common Share (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/WarrantLiabilitiesDetails" id="WarrantLiabilitiesDetails">
        <!--Parent Role: Warrant Liabilities-->
        <link:definition>090600 - Disclosure - Warrant Liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/StockBasedCompensationDetails" id="StockBasedCompensationDetails">
        <!--Parent Role: Stock Based Compensation-->
        <link:definition>090700 - Disclosure - Stock Based Compensation (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/StockBasedCompensationScheduleOfEmployeeAndNonEmployeeServiceShareBasedCompensationDetails" id="StockBasedCompensationScheduleOfEmployeeAndNonEmployeeServiceShareBasedCompensationDetails">
        <!--Parent Role: Stock Based Compensation-->
        <link:definition>090702 - Disclosure - Stock Based Compensation, Schedule of Employee and Non Employee Service Share Based Compensation (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/StockBasedCompensationByExercisePriceRangeDetails" id="StockBasedCompensationByExercisePriceRangeDetails">
        <!--Parent Role: Stock Based Compensation-->
        <link:definition>090704 - Disclosure - Stock Based Compensation, by Exercise Price Range (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/FairValueMeasurementsDetails" id="FairValueMeasurementsDetails">
        <!--Parent Role: Fair Value Measurements-->
        <link:definition>090800 - Disclosure - Fair Value Measurements (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/LiquidityAndCapitalResourcesDetails" id="LiquidityAndCapitalResourcesDetails">
        <!--Parent Role: Liquidity and Capital Resources-->
        <link:definition>090900 - Disclosure - Liquidity and Capital Resources (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/EquityTransactionsDetails" id="EquityTransactionsDetails">
        <!--Parent Role: Equity Transactions-->
        <link:definition>091000 - Disclosure - Equity Transactions (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/IncomeTaxesDetails" id="IncomeTaxesDetails">
        <!--Parent Role: Income Taxes-->
        <link:definition>091100 - Disclosure - Income Taxes (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/CommitmentsAndContingenciesDetails" id="CommitmentsAndContingenciesDetails">
        <!--Parent Role: Commitments and contingencies-->
        <link:definition>091200 - Disclosure - Commitments and contingencies (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://cytrx.com/role/SubsequentEventsDetails" id="SubsequentEventsDetails">
        <!--Parent Role: Subsequent Events-->
        <link:definition>091300 - Disclosure - Subsequent Events (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xs:appinfo>
  </xs:annotation>
  <xs:import namespace="http://fasb.org/us-gaap/2016-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd" />
  <xs:import namespace="http://xbrl.sec.gov/dei/2014-01-31" schemaLocation="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd" />
  <xs:import namespace="http://xbrl.sec.gov/invest/2013-01-31" schemaLocation="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd" />
  <xs:import namespace="http://xbrl.sec.gov/country/2016-01-31" schemaLocation="http://xbrl.sec.gov/country/2016/country-2016-01-31.xsd" />
  <xs:import namespace="http://xbrl.sec.gov/currency/2016-01-31" schemaLocation="http://xbrl.sec.gov/currency/2016/currency-2016-01-31.xsd" />
  <xs:import namespace="http://xbrl.sec.gov/exch/2016-01-31" schemaLocation="http://xbrl.sec.gov/exch/2016/exch-2016-01-31.xsd" />
  <xs:import namespace="http://xbrl.sec.gov/naics/2011-01-31" schemaLocation="http://xbrl.sec.gov/naics/2011/naics-2011-01-31.xsd" />
  <xs:import namespace="http://xbrl.sec.gov/sic/2011-01-31" schemaLocation="http://xbrl.sec.gov/sic/2011/sic-2011-01-31.xsd" />
  <xs:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xs:import namespace="http://www.xbrl.org/2009/role/net" schemaLocation="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd" />
  <xs:import namespace="http://xbrl.sec.gov/stpr/2011-01-31" schemaLocation="http://xbrl.sec.gov/stpr/2011/stpr-2011-01-31.xsd" />
  <xs:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xs:import namespace="http://www.xbrl.org/2004/ref" schemaLocation="http://www.xbrl.org/2004/ref-2004-08-10.xsd" />
  <xs:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <xs:import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
  <xs:import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd" />
  <xs:import namespace="http://fasb.org/us-types/2016-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2016/elts/us-types-2016-01-31.xsd" />
  <xs:import namespace="http://www.xbrl.org/2009/arcrole/fact-explanatoryFact" schemaLocation="http://www.xbrl.org/lrr/arcrole/factExplanatory-2009-12-16.xsd" />
  <xs:element name="LiquidityAndCapitalResourcesAbstract" id="cytr_LiquidityAndCapitalResourcesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="LiquidityAndCapitalResourcesTextBlock" id="cytr_LiquidityAndCapitalResourcesTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="EstimatedProjectedExpendituresTable" id="cytr_EstimatedProjectedExpendituresTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="HerculesTechnologyGrowthCapitalIncAndHerculesTechnologyIIILPMember" id="cytr_HerculesTechnologyGrowthCapitalIncAndHerculesTechnologyIIILPMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="NantCellIncMember" id="cytr_NantCellIncMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="OtherProgramsMember" id="cytr_OtherProgramsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="InterestAndTermLoanPaymentMember" id="cytr_InterestAndTermLoanPaymentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="OtherGeneralAndAdministrativeExpensesMember" id="cytr_OtherGeneralAndAdministrativeExpensesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="GeneralOperationMember" id="cytr_GeneralOperationMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="AldoxorubicinMember" id="cytr_AldoxorubicinMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="EstimatedProjectedExpenditureLineItems" id="cytr_EstimatedProjectedExpenditureLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="CurrentlyProjectedExpendituresForClinicalPrograms" id="cytr_CurrentlyProjectedExpendituresForClinicalPrograms" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" />
  <xs:element name="WarrantLiabilityFairValueDisclosure" id="cytr_WarrantLiabilityFairValueDisclosure" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="PotentialFutureMilestonePaymentsOnEachAdditionalFinalMarketingApproval" id="cytr_PotentialFutureMilestonePaymentsOnEachAdditionalFinalMarketingApproval" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="NumberOfCompetingDerivativeComplaints" id="cytr_NumberOfCompetingDerivativeComplaints" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="CommonStockSharesIssuedFromExerciseOfWarrants" id="cytr_CommonStockSharesIssuedFromExerciseOfWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="WarrantLiabilitiesAbstract" id="cytr_WarrantLiabilitiesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="WarrantLiabilitiesTextBlock" id="cytr_WarrantLiabilitiesTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="StockIssuedInConnectionWithTheClassActionSettlement" id="cytr_StockIssuedInConnectionWithTheClassActionSettlement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" />
  <xs:element name="WarrantLiabilityExercise" id="cytr_WarrantLiabilityExercise" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" />
  <xs:element name="AdjustmentsToAdditionalPaidInCapitalWarrantsIssuedInConnectionWithTermLoan" id="cytr_AdjustmentsToAdditionalPaidInCapitalWarrantsIssuedInConnectionWithTermLoan" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" />
  <xs:element name="ScheduleOfWeightedAverageAssumptionsTableTextBlock" id="cytr_ScheduleOfWeightedAverageAssumptionsTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="DescriptionOfCompanyAndBasisOfPresentationAbstract" id="cytr_DescriptionOfCompanyAndBasisOfPresentationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="PreferredStockStatedValue" id="cytr_PreferredStockStatedValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="EstimatedAnnualizedForfeitureRate" id="cytr_EstimatedAnnualizedForfeitureRate" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="RestrictedStockAbstract" id="cytr_RestrictedStockAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="StockIncentivePlanMember" id="cytr_StockIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="LongTermIncentivePlanMember" id="cytr_LongTermIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="NonEmployeesMember" id="cytr_NonEmployeesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="FormerExecutiveMember" id="cytr_FormerExecutiveMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="EmployeesAndDirectorsMember" id="cytr_EmployeesAndDirectorsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="ShareBasedCompensationStockOptionsActivityAbstract" id="cytr_ShareBasedCompensationStockOptionsActivityAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisedForfeituresExpiredInPeriod" id="cytr_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisedForfeituresExpiredInPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisedForfeituresExpiredInPeriodWeightedAverageExercisePrice" id="cytr_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisedForfeituresExpiredInPeriodWeightedAverageExercisePrice" type="num:perShareItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="EmployeesMember" id="cytr_EmployeesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="StockOptionsAndWarrantsMember" id="cytr_StockOptionsAndWarrantsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="NumberOfClassesOfUltraHighPotencyDrugConjugates" id="cytr_NumberOfClassesOfUltraHighPotencyDrugConjugates" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="NumberOfPatientsTestedForVariousTypesOfCancer" id="cytr_NumberOfPatientsTestedForVariousTypesOfCancer" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="FutureMilestonePaymentReceivableUnderLicenseAgreement" id="cytr_FutureMilestonePaymentReceivableUnderLicenseAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" />
  <xs:element name="NumberOfYearsOrphanDrugDesignationProvidesSeveralBenefitsOfMarketExclusivityAfterApproval" id="cytr_NumberOfYearsOrphanDrugDesignationProvidesSeveralBenefitsOfMarketExclusivityAfterApproval" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="NumberOfYearsOfSoftTissueSarcomasConfersMarketAmongOtherBenefits" id="cytr_NumberOfYearsOfSoftTissueSarcomasConfersMarketAmongOtherBenefits" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="PercentageOfCommonStockPremiumAtMarketPrice" id="cytr_PercentageOfCommonStockPremiumAtMarketPrice" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" />
  <xs:element name="UnrestrictedMember" id="cytr_UnrestrictedMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="DocumentAndEntityInformationAbstract" id="cytr_DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="ScheduleOfTotalStockBasedCompensationExpenseFromStockOptionsAndWarrantsTableTextBlock" id="cytr_ScheduleOfTotalStockBasedCompensationExpenseFromStockOptionsAndWarrantsTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="PercentageOfStockIssuableUponExerciseOfWarrants" id="cytr_PercentageOfStockIssuableUponExerciseOfWarrants" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="NumberOfDaysToCalculateVolumeWeightedAveragePriceOfCommonStock" id="cytr_NumberOfDaysToCalculateVolumeWeightedAveragePriceOfCommonStock" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="ChargesOfPrepaymentOfDebt" id="cytr_ChargesOfPrepaymentOfDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" />
  <xs:element name="DebtInstrumentUnamortizedDiscountCurrentAndIssuanceCost" id="cytr_DebtInstrumentUnamortizedDiscountCurrentAndIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
  <xs:element name="TermLoanFeePayableNoncurrent" id="cytr_TermLoanFeePayableNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="WarrantsClassifiedAsEquityWarrantFairValue" id="cytr_WarrantsClassifiedAsEquityWarrantFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="DebtInstrumentMinimumCashBalanceRequiredToBeMaintained" id="cytr_DebtInstrumentMinimumCashBalanceRequiredToBeMaintained" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
  <xs:element name="DebtInstrumentFaceAmountCurrent" id="cytr_DebtInstrumentFaceAmountCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="DebtInstrumentFaceAmountNoncurrent" id="cytr_DebtInstrumentFaceAmountNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="DebtInstrumentUnamortizedDiscountNoncurrentAndIssuanceCost" id="cytr_DebtInstrumentUnamortizedDiscountNoncurrentAndIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
  <xs:element name="DebtInstrumentAmendedMaturityDate" id="cytr_DebtInstrumentAmendedMaturityDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="RangeFourMember" id="cytr_RangeFourMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="RangeOneMember" id="cytr_RangeOneMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="RangeTwoMember" id="cytr_RangeTwoMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="RangeThreeMember" id="cytr_RangeThreeMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="ShareBasedCompensationSharesAuthorizedUnderSignificantRangesOfOutstandingStockOptionPlansInPeriodAbstract" id="cytr_ShareBasedCompensationSharesAuthorizedUnderSignificantRangesOfOutstandingStockOptionPlansInPeriodAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAveragePrice" id="cytr_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAveragePrice" type="us-types:perUnitItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" />
</xs:schema>


