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  <xsd:element id="vtgn_UpfrontLicensePayment" name="UpfrontLicensePayment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_WarrantsExpiringDecember92024Member" name="WarrantsExpiringDecember92024Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_WarrantsExpiringJuly252025Member" name="WarrantsExpiringJuly252025Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vtgn_WarrantsIssuedInConnectionWithEquityFinancingPolicyTextBlock" name="WarrantsIssuedInConnectionWithEquityFinancingPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_i3StrategyPartnersMember" name="i3StrategyPartnersMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-10-commitments-and-contingencies-minimum-lease-payments-details" name="statement-statement-note-10-commitments-and-contingencies-minimum-lease-payments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-10-commitments-and-contingencies-operating-activities-in-cash-flow-statements-details" name="statement-statement-note-10-commitments-and-contingencies-operating-activities-in-cash-flow-statements-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-10-commitments-and-contingencies-operating-lease-cost-details" name="statement-statement-note-10-commitments-and-contingencies-operating-lease-cost-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-10-commitments-and-contingencies-operating-lease-in-condensed-consolidated-balance-sheet-details" name="statement-statement-note-10-commitments-and-contingencies-operating-lease-in-condensed-consolidated-balance-sheet-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-10-commitments-and-contingencies-tables" name="statement-statement-note-10-commitments-and-contingencies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-3-summary-of-significant-accounting-policies-schedule-of-changes-in-contract-liabilities-details" name="statement-statement-note-3-summary-of-significant-accounting-policies-schedule-of-changes-in-contract-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-3-summary-of-significant-accounting-policies-schedule-of-contract-acquisition-costs-details" name="statement-statement-note-3-summary-of-significant-accounting-policies-schedule-of-contract-acquisition-costs-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-3-summary-of-significant-accounting-policies-schedule-of-fair-value-of-options-granted-blackscholes-option-pricing-model-details" name="statement-statement-note-3-summary-of-significant-accounting-policies-schedule-of-fair-value-of-options-granted-blackscholes-option-pricing-model-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-3-summary-of-significant-accounting-policies-schedule-of-potentially-dilutive-securities-excluded-from-earnings-per-share-computation-details" name="statement-statement-note-3-summary-of-significant-accounting-policies-schedule-of-potentially-dilutive-securities-excluded-from-earnings-per-share-computation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-3-summary-of-significant-accounting-policies-schedule-of-stockbased-compensation-expense-details" name="statement-statement-note-3-summary-of-significant-accounting-policies-schedule-of-stockbased-compensation-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-3-summary-of-significant-accounting-policies-tables" name="statement-statement-note-3-summary-of-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-4-prepaid-expenses-and-other-current-assets-schedule-of-prepaid-expenses-and-other-current-assets-details" name="statement-statement-note-4-prepaid-expenses-and-other-current-assets-schedule-of-prepaid-expenses-and-other-current-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-4-prepaid-expenses-and-other-current-assets-tables" name="statement-statement-note-4-prepaid-expenses-and-other-current-assets-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-5-property-and-equipment-net-schedule-of-assets-subject-to-financing-lease-details" name="statement-statement-note-5-property-and-equipment-net-schedule-of-assets-subject-to-financing-lease-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-5-property-and-equipment-net-schedule-of-property-and-equipment-details" name="statement-statement-note-5-property-and-equipment-net-schedule-of-property-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-5-property-and-equipment-net-tables" name="statement-statement-note-5-property-and-equipment-net-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-6-accrued-expenses-schedule-of-accrued-expenses-details" name="statement-statement-note-6-accrued-expenses-schedule-of-accrued-expenses-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-6-accrued-expenses-tables" name="statement-statement-note-6-accrued-expenses-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-7-note-payable-summary-of-notes-payable-details" name="statement-statement-note-7-note-payable-summary-of-notes-payable-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-7-note-payable-tables" name="statement-statement-note-7-note-payable-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-8-capital-stock-schedule-of-warrants-details" name="statement-statement-note-8-capital-stock-schedule-of-warrants-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-note-8-capital-stock-tables" name="statement-statement-note-8-capital-stock-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vtgn_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
