Exhibit 10.36

FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT

This FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT (this “Agreement”) is
entered into as of November 19, 2019, by and among INNOVATUS LIFE SCIENCES
LENDING FUND I, LP, a Delaware limited partnership (together with its successors
and assigns, “Innovatus”), as collateral agent (in such capacity, together with
its successors and assigns in such capacity, “Collateral Agent”), the Lenders
listed on Schedule 1.1 thereof or otherwise a party thereto from time to time
(each a “Lender” and collectively, “Lenders”), and EXAGEN INC., a Delaware
corporation (f/k/a EXAGEN DIAGNOSTICS, INC.) (“Borrower”).

Recitals
A. Collateral Agent, Lenders, and Borrower have entered into that certain Loan
and Security Agreement dated as of September 7, 2017 (as the same may from time
to time be amended, modified, supplemented or restated, the “Loan Agreement”).
B. Lenders have extended credit to Borrower for the purposes permitted in the
Loan Agreement.
C. Borrower has requested that Collateral Agent and Lenders amend the Loan
Agreement as more fully set forth herein.
D. Collateral Agent and Lenders have agreed to amend certain provisions of the
Loan Agreement, but only to the extent, in accordance with the terms, subject to
the conditions and in reliance upon the representations and warranties set forth
below.
E. As of the date hereof, the outstanding principal balance of the Term Loans,
including payable in-kind interest which has been capitalized, is $26,161,884.94
(See Annex X).
Agreement
        Now, Therefore, in consideration of the foregoing recitals and other
good and valuable consideration, the receipt and adequacy of which is hereby
acknowledged, and intending to be legally bound, the parties hereto agree as
follows:
1.Definitions. Capitalized terms used but not defined in this Agreement shall
have the meanings given to them in the Loan Agreement.
2.Amendments.
2.1 Section 2.2 (Term Loans). Section 2.2(b) of the Loan Agreement is amended
and restated as follows:
(b) Repayment. Borrower shall make monthly payments of interest only commencing
on the second (2nd) Payment Date following the Funding Date of the Term Loan,
and continuing on the Payment Date of each successive month thereafter through
and including the Payment Date immediately preceding the Amortization Date.
Borrower agrees to pay, on the Funding Date of the Term Loan, any initial
partial monthly interest payment otherwise due for the period between the
Funding Date of such Term Loan and the first Payment Date after such Funding
Date. Commencing on the Amortization Date, and continuing on the Payment Date of
each month thereafter, Borrower shall make consecutive equal monthly payments of
principal,

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plus interest, in arrears, to each Lender, as calculated by Collateral Agent
(which calculations shall be deemed correct absent manifest error) based upon:
(1) the amount of such Lender’s Term Loan, (2) the effective rate of interest,
as determined in Section 2.3(a), and (3) a repayment schedule equal to
twenty-four (24) months. All unpaid principal and accrued and unpaid interest
with respect to the Term Loan is due and payable in full on the Maturity Date.
The Term Loan may only be prepaid in accordance with Sections 2.2(c) and 2.2(d).

2.2 Section 2.2 (Term Loans). Section 2.2(d) of the Loan Agreement is amended
and restated as follows:
(d) Permitted Prepayment of Term Loan. After the first anniversary of the First
Amendment Effective Date only, Borrower shall have the option to prepay all or
part of the Term Loan advanced by the Lenders under this Agreement, provided
Borrower (i) provides written notice to Collateral Agent of its election to
prepay the Term Loan at least five (5) days prior to such prepayment, (ii) in
the event of a partial prepayment, prepays such part of the Term Loan in a
denomination that is a whole number multiple of Five Million Dollars
($5,000,000.00), and (iii) pays to the Lenders on the date of such prepayment,
payable to each Lender in accordance with its respective Pro Rata Share, an
amount equal to the sum of (A) the portion of outstanding principal of the Term
Loan being prepaid plus all accrued and unpaid interest thereon through the
prepayment date, (B) the applicable Final Payment with respect to the portion of
the Term Loan being prepaid, (C) all other Obligations that are then due and
payable, including Lenders’ Expenses and interest at the Default Rate with
respect to any past due amounts pursuant to the terms of this Agreement, and (D)
the applicable Prepayment Fee with respect to the portion of the Term Loan being
prepaid. For the sake of clarity, any partial prepayment shall be applied
pro-rata to all outstanding amounts under the Term Loan, and shall be applied on
a pro-rata basis to all remaining payments outstanding in inverse order of
maturity.

2.3 Section 2.3 (Payment of Interest on the Term Loan). Section 2.3(a) of the
Loan Agreement is amended and restated as follows:
(a) Interest Rate. Subject to Section 2.3(b), the principal amount outstanding
under the Term Loan shall accrue interest at a fixed per annum rate equal to
eight and one-half percent (8.50%), which interest shall be payable monthly in
arrears in accordance with Sections 2.2(b) and 2.3(e); provided that two percent
(2.00%) of such eight and one-half percent (8.50%) interest rate shall be
payable in-kind through the Amortization Date by adding an amount equal to such
two percent (2.00%) interest to the then outstanding principal balance on a
monthly basis so as to increase the outstanding principal balance of such Term
Loan on each Payment Date and which amount shall be payable when the principal
amount of the Term Loan is payable in accordance with Sections 2.2(b) and 2.3(e)
and on which principal amount interest shall be owed pursuant to Section 2.3(a).

2.4 Section 6.11 (Minimum Liquidity). Section 6.11 of the Loan Agreement is
amended and restated as follows:
6.11 Minimum Liquidity. Borrower shall at all times maintain minimum
unrestricted cash and Cash Equivalents, in an account subject to a control
agreement in favor of Collateral Agent, in an amount equal to Two Million
Dollars ($2,000,000.00).

2.5 Section 6.15 (Performance to Plan). A new Section 6.15 is added to the Loan
Agreement as follows:
6.15 Performance to Plan. So long as the Performance Period is not in effect,
Borrower shall achieve minimum trailing twelve (12) month revenue under GAAP,

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measured at the end of each calendar quarter commencing with the quarter ending
December 31, 2019, greater than seventy percent (70%) of projected revenue under
GAAP (such projections attached hereto as Annex Q, the “Management Plan”) (the
“Performance Covenant”). Borrower’s failure to maintain the Performance Covenant
may be cured by the Equity Cure. Upon the Equity Cure, the Performance Covenant
shall be based on the New Management Plan.

2.6 Section 8.2 (Covenant Default). Section 8.2(a) of the Loan Agreement is
amended and restated as follows:
(a) Borrower or any of its Subsidiaries fails or neglects to perform any
obligation in Sections 6.2 (Financial Statements, Reports, Certificates), 6.4
(Taxes), 6.5 (Insurance), 6.6 (Operating Accounts), 6.7 (Protection of
Intellectual Property Rights), 6.11 (Minimum Liquidity), 6.15 (Performance to
Plan) or Borrower violates any provision in Section 7; or

2.7 Section 13 (Definitions). The following terms and their definition are added
to or amended and restated in Section 13 of the Loan Agreement as follows:
“Amortization Date” is the thirty-seventh (37th) Payment Date following the
First Amendment Effective Date.

“Cash Flow” is an amount equal to (i) Borrower’s cash flow from operations,
minus (ii) Borrower’s capital expenditures.

“Equity Cure” means Borrower’s receipt, within sixty (60) days (or such longer
period as acceptable to Collateral Agent and Innovatus in their sole reasonable
discretion based on Borrower’s good faith efforts to complete the Equity Cure)
of any failure to achieve the Performance Covenant, of gross proceeds from the
sale and issuance of Borrower’s equity securities or Subordinated Debt, which in
each case will not have any redemption, clawback, escrow or similar terms of at
least an amount necessary for Borrower to achieve Cash Flow of at least Zero
Dollars ($0) prior to the Maturity Date based on a new management plan provided
by the Borrower (the “New Management Plan”), which is subject to Collateral
Agent’s and Innovatus’ approval in their sole reasonable discretion.

“First Amendment Effective Date” is November 19, 2019.

“Maturity Date” is November 19, 2024.

“Performance Period” is, provided no Event of Default has occurred and is
continuing, the period (a) commencing on the day that Borrower provides to
Collateral Agent and Lenders a written report that (i) Borrower has achieved
trailing twelve (12) month revenue under GAAP of at least One Hundred Million
Dollars ($100,000,000.00), and (ii) Borrower has been cash flow positive for at
least two (2) consecutive quarters (collectively, the “Performance
Requirement”), and (b) terminating on the earlier to occur of (i) the occurrence
of an Event of Default, and (ii) the first day thereafter in which Borrower
fails to maintain the Performance Requirement as disclosed in any Compliance
Certificate.

“Prepayment Fee” is, with respect to any Term Loan subject to prepayment prior
to the Maturity Date, whether by mandatory or voluntary prepayment, acceleration
or otherwise, as indicated, an additional fee payable to the Lenders in amount
equal to:

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(i) for any prepayment made after the First Amendment Effective Date through and
including the first anniversary of the First Amendment Effective Date, which,
pursuant to Section 2.2(d), may not be a voluntary prepayment, three percent
(3.00%) of the principal amount of the Term Loan prepaid;

(ii) for any prepayment made after the first anniversary of the First Amendment
Effective Date through and including the second anniversary of the First
Amendment Effective Date, two percent (2.00%) of the principal amount of the
Term Loan prepaid;

(iii) for any prepayment made after the second anniversary of the First
Amendment Effective Date through and including the third anniversary of the
First Amendment Effective Date, one percent (1.00%) of the principal amount of
the Term Loan prepaid; and

(iv) for any prepayment made after the third anniversary of the First Amendment
Effective Date, zero percent (0%) of the principal amount of the Term Loan
prepaid.

2.8 Section 13 (Definitions). The following terms and their definitions are
deleted in their entirety from Section 13 of the Loan Agreement:
“Gross Margin”; “Gross Profit”; “Interest-Only Milestones”; “I/O Gross Margin
Milestone”; “I/O Gross Profit Milestone”; “I/O Revenue Milestone”; “Permitted
Prepayment Mandatory Warrant”; “Permitted Prepayment Reason”; “Prepayment
Mandatory Fee”.

2.9 Exhibit C (Compliance Certificate) to the Loan Agreement is replaced with
Exhibit C attached hereto.
2.10 Annex Q (Management Plan) to the Loan Agreement is replaced with Annex Q
attached hereto.
2.11 Annex X (Loan Interest Rate and Payment of Principal Schedule) attached
hereto is added to the Loan Agreement.
2.12 Schedule I (Prepayment Mandatory Fee) to the Loan Agreement is deleted in
its entirety.
3.Limitation of Agreement.
3.1 This Agreement is effective for the purposes set forth herein and shall be
limited precisely as written and shall not be deemed to (a) be a consent to any
amendment, waiver or modification of any other term or condition of any Loan
Document, or (b) otherwise prejudice any right or remedy which Collateral Agent
and Lenders may now have or may have in the future under or in connection with
any Loan Document.
3.2 This Agreement shall be construed in connection with and as part of the Loan
Documents, and all terms, conditions, representations, warranties, covenants and
agreements set forth in the Loan Documents are hereby ratified and confirmed and
shall remain in full force and effect.
4.Representations and Warranties. Borrower represents and warrants to Collateral
Agent and Lenders as follows:

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4.1 (a) the representations and warranties contained in the Loan Documents are
true, accurate and complete in all material respects as of the date hereof
(except to the extent such representations and warranties relate to an earlier
date, in which case they are true and correct as of such date), and (b) no Event
of Default has occurred and is continuing immediately before and after giving
effect to this Agreement;
4.2 Borrower has the power and authority to execute and deliver this Agreement
and to perform its obligations under the Loan Agreement;
4.3 The organizational documents of Borrower delivered to Collateral Agent and
Lenders on the Effective Date or subsequent thereto remain true, accurate and
complete and have not been amended, supplemented or restated and are and
continue to be in full force and effect;
4.4 The execution and delivery by Borrower of this Agreement and the performance
by Borrower of its obligations under the Loan Agreement have been duly
authorized by all necessary action on the part of Borrower;
4.5 The execution and delivery by Borrower of this Agreement and the performance
by Borrower of its obligations under the Loan Agreement do not and will not
contravene (a) any law or regulation binding on or affecting Borrower, (b) any
contractual restriction with a Person binding on Borrower, (c) any order,
judgment or decree of any court or other governmental or public body or
authority, or subdivision thereof, binding on Borrower, or (d) the
organizational documents of Borrower;
4.6 The execution and delivery by Borrower of this Agreement and the performance
by Borrower of its obligations under the Loan Agreement do not require any
order, consent, approval, license, authorization or validation of, or filing,
recording or registration with, or exemption by any governmental or public body
or authority, or subdivision thereof, binding on either Borrower, except as
already has been obtained or made; and
4.7 This Agreement has been duly executed and delivered by Borrower and is the
binding obligation of Borrower, enforceable against Borrower in accordance with
its terms, except as such enforceability may be limited by bankruptcy,
insolvency, reorganization, liquidation, moratorium or other similar laws of
general application and equitable principles relating to or affecting creditors’
rights.
5.Prior Agreement. The Loan Documents are hereby ratified and reaffirmed and
shall remain in full force and effect. This Agreement is not a novation and the
terms and conditions of this Agreement shall be in addition to and supplemental
to all terms and conditions set forth in the Loan Documents. In the event of any
conflict or inconsistency between this Agreement and the terms of such
documents, the terms of this Agreement shall be controlling, but such document
shall not otherwise be affected or the rights therein impaired.
6.Integration. This Agreement and the Loan Documents represent the entire
agreement about this subject matter and supersede prior negotiations or
agreements. All prior agreements, understandings, representations, warranties,
and negotiations between the parties about the subject matter of this Agreement
and the Loan Documents merge into this Agreement and the Loan Documents.
7.Counterparts. This Agreement may be executed in any number of counterparts and
all of such counterparts taken together shall be deemed to constitute one and
the same instrument.
8.Conditions to Effectiveness. This Agreement shall be deemed effective upon the
due execution and delivery to Collateral Agent and Lenders, in form and
substance reasonably satisfactory to Collateral Agent and each Lender, such
documents, and completion of such other matters, as Collateral Agent and each
Lender may reasonably deem necessary or appropriate (and requested in writing at
least three Business Days prior to the date hereof), including, without
limitation:

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a)  this Agreement duly executed by each party hereto;
b) a duly executed corporate borrowing certificate dated as of the date hereof;
and
c) Borrower’s payment of all Lenders’ Expenses incurred through the date of this
Agreement to the extent due and payable pursuant to Sections 2.4(d) or 12.2 of
the Loan Agreement, which amount for the documentation and negotiation of this
Agreement shall not exceed Fifteen Thousand Dollars ($15,000).
9.Miscellaneous.
9.1 This Agreement shall constitute a Loan Document under the Loan Agreement;
the failure to comply with the covenants contained herein shall constitute an
Event of Default under the Loan Agreement; and all obligations included in this
Agreement (including, without limitation, all obligations for the payment of
principal, interest, fees, and other amounts and expenses) shall constitute
obligations under the Loan Agreement and secured by the Collateral.
9.2 Each provision of this Agreement is severable from every other provision in
determining the enforceability of any provision.
10.Governing Law. This Agreement and the rights and obligations of the parties
hereto shall be governed by and construed in accordance with the laws of the
State of New York.
[Signature pages follow.]

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed
as of the date first written above.

BORROWER:

EXAGEN INC.

By: /s/Kamal Adawi

Name: Kamal Adawi

Title: Chief Financial Officer

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed
as of the date first written above.

COLLATERAL AGENT AND LENDER:

INNOVATUS LIFE SCIENCES LENDING FUND I, LP

By: Innovatus Life Sciences GP, LP
Its: General Partner

By: /s/ Andrew Hobson 

Name: Andrew Hobson

Title: Authorized Signatory

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EXHIBIT C

Compliance Certificate

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ANNEX Q
(Management Plan)

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ANNEX X

(Loan Interest Rate and Payment of Principal Schedule)