Exhibit 10.1

SIXTH AMENDMENT TO LOAN AND SECURITY AGREEMENT

THIS SIXTH AMENDMENT (this “Amendment”), dated as of April 27, 2017 and
effective as of the Effective Time of the Merger (each as defined below), to the
Loan and Security Agreement, dated as of August 11, 2015 (as amended by the
Prior Amendments (as defined below), the “Loan Agreement”), is made by and among
MAST THERAPEUTICS, INC., a Delaware corporation, which following the Merger (as
defined below) will be renamed “Savara, Inc.” (“Borrower”), HERCULES CAPITAL,
INC. (formerly known as Hercules Technology Growth Capital, Inc.), a Maryland
corporation, as administrative agent (“Agent”), and the lender party hereto
(“Lender”).

RECITALS

A.    Borrower, Agent and Lender are parties to the Loan Agreement as previously
amended by First Amendment to Loan and Security Agreement dated as of
September 28, 2015, Second Amendment to Loan and Security Agreement effective as
of December 31, 2015, Third Amendment to Loan and Security Agreement effective
as of February 25, 2016, Fourth Amendment to Loan and Security Agreement
effective as of July 22, 2016, and Fifth Amendment to Loan and Security
Agreement dated as of March 3, 2017 and effective as of the Effective Time of
the Merger (the “Fifth Amendment” and together with the other foregoing,
collectively, the “Prior Amendments”).

B.    Borrower is party to that certain Agreement and Plan of Merger and
Reorganization, dated January 6, 2017, among Borrower, Victoria Merger Corp., a
Delaware corporation (the “Merger Sub”), and Savara Inc., a Delaware corporation
(the “Surviving Corporation”), pursuant to which, among other things, the Merger
Sub will be merged with and into the Surviving Corporation, with the Surviving
Corporation remaining as the surviving entity and a wholly-owned subsidiary of
Borrower (and which will be renamed “Aravas Inc.”), and the Surviving
Corporation’s stockholders will receive shares of Borrower’s common stock in
exchange for capital stock held in the Surviving Corporation (the “Merger
Agreement” and such transactions, the “Merger”).

C.    Subject to the conditions set forth herein, the parties hereto wish to
further amend the Loan Agreement as set forth herein to permit certain
investments in a wholly-owned subsidiary of the Surviving Corporation, Savara
ApS.

D.    The Loan Agreement may be amended pursuant to Section 11.3(b) thereof by
the written agreement of Borrower, Agent and Lender (which, for the avoidance of
doubt, is the Required Lender).

AGREEMENT

NOW, THEREFORE, for valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the parties hereto agree as follows:

SECTION 1.    Effectiveness. Subject to all of the terms and conditions set
forth in this Amendment, this Amendment shall become effective immediately at
the Effective Time (as defined in the Merger Agreement); provided, however, this
Amendment shall terminate in all

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respects if (a) the Merger Agreement is terminated prior to the Effective Time,
(b) the Merger Agreement is amended, or any material obligation thereunder is
waived, in a manner that adversely affects the agreements and understandings set
forth in this Amendment or the Loan Agreement or (c) the Merger is not
consummated on or prior to April 30, 2017.

SECTION 2.    Defined Terms. Capitalized terms used but not defined herein
(including in the recitals) shall have the meanings assigned to such terms in
the Loan Agreement and the Prior Amendments.

SECTION 3.    Amendments to Loan Agreement. Subject to all of the terms and
conditions set forth in this Amendment, Borrower, Agent and Lender hereby agree
to the following amendments to the Loan Agreement.

(A) The definition of “Permitted Investment” is hereby amended and restated in
its entirety to read as follows:

““Permitted Investment” means: (i) Investments existing on the Closing Date
which are disclosed in Schedule 1B; (ii) (a) marketable direct obligations
issued or unconditionally guaranteed by the United States of America or any
agency or any State thereof maturing within eighteen months from the date of
acquisition thereof, (b) commercial paper maturing no more than eighteen months
from the date of creation thereof and currently having a rating of at least A-2
or P-2 from either Standard & Poor’s Corporation or Moody’s Investors Service,
(c) certificates of deposit issued by any bank with assets of at least
$500,000,000 maturing no more than eighteen months from the date of investment
therein, and (d) money market accounts; (iii) repurchases of stock from former
employees, directors, or consultants of Borrower under the terms of applicable
repurchase agreements at the original issuance price of such securities in an
aggregate amount not to exceed $250,000 in any fiscal year, provided that no
Event of Default has occurred, is continuing or would exist after giving effect
to the repurchases; (iv) Investments accepted in connection with Permitted
Transfers; (v) Investments (including debt obligations) received in connection
with the bankruptcy or reorganization of customers or suppliers and in
settlement of delinquent obligations of, and other disputes with, customers or
suppliers arising in the ordinary course of Borrower’s business;
(vi) Investments consisting of notes receivable of, or prepaid royalties and
other credit extensions, to customers and suppliers who are not Affiliates, in
the ordinary course of business, provided that this subparagraph (vi) shall not
apply to Investments of Borrower in any Subsidiary; (vii) Investments consisting
of loans not involving the net transfer on a substantially contemporaneous basis
of cash proceeds to employees, officers or directors relating to the purchase of
capital stock of Borrower pursuant to employee stock purchase plans or other
similar agreements approved by Borrower’s Board of Directors; (viii) Investments
consisting of travel advances, relocation loans and other loans and advances (or
guarantees thereof) to employees, officers and directors in the ordinary course
of business and otherwise in compliance with the Sarbanes-Oxley Act of 2002, as
amended, and not to exceed $250,000 outstanding at any one time in the
aggregate; (ix) Investments in a Qualified Subsidiary so long as such Qualified
Subsidiary has

 

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entered into a Joinder Agreement or has otherwise become party to this
Agreement; (x) Investments in Savara ApS (“Savara Denmark”) to the extent
necessary to fund the operating expenses of Savara Denmark in the ordinary
course of its business, provided that (A) Borrower shall not invest more than
$13,000,000 in Savara Denmark during any 12-month period, (B) at no time shall
the aggregate amount of cash held in all accounts of Savara Denmark exceed
$2,000,000, (C) Savara Denmark shall not have issued any secured Indebtedness,
and (D) gross unsecured liabilities of Savara Denmark owed to parties other than
Borrower or its Affiliates shall not exceed $5,000,000 in the aggregate at any
given time; (xi) other than as provided in clause (x) of this definition,
Investments in Foreign Subsidiaries approved in advance in writing by Agent;
(xii) Investments by any Qualified Subsidiary into Borrower; (xiii) joint
ventures or strategic alliances in the ordinary course of Borrower’s business
consisting of the nonexclusive licensing of technology, the development of
technology or the providing of technical support, provided that any cash
Investments by Borrower do not exceed $250,000 in the aggregate in any fiscal
year; and (xiv) additional Investments that do not exceed $250,000 in the
aggregate.”

(B) The definition of “Permitted Transfers” is hereby amended and restated in
its entirety to read as follows:

““Permitted Transfers” means (i) sales of Inventory in the ordinary course of
business; (ii) non-exclusive licenses and similar arrangements for the use of
Intellectual Property in the ordinary course of business and licenses that could
not result in a legal transfer of title of the licensed property but that may be
exclusive in respects other than territory and that may be exclusive as to
territory only as to discreet geographical areas outside of the United States in
the ordinary course of business; (iii) dispositions of worn-out, obsolete or
surplus Equipment at fair market value in the ordinary course of business;
(iv) transfers of cash to Savara Denmark permitted pursuant to clause (x) of the
definition of Permitted Investment; and (v) other Transfers of assets having a
fair market value of not more than $250,000 in the aggregate in any fiscal
year.”

(C) Section 5.12 of the Loan Agreement is hereby amended and restated in its
entirety to read as follows:

“5.12    Financial Accounts. Exhibit G, as it may be updated by Borrower from
time to time in a written notice provided to Agent, is a true, correct and
complete list of (a) all banks and other financial institutions at which
Borrower or any direct or indirect Subsidiary maintains Deposit Accounts or
other accounts and (b) all institutions at which Borrower or any direct or
indirect Subsidiary maintains an account holding Investment Property, and
Exhibit G correctly identifies the name, address and telephone number of each
bank or other institution, the name in which the account is held, a description
of the purpose of the account, and the complete account number therefor.”

 

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(D) A new Section 5.15 is added to Section 5 of the Loan Agreement to read as
follows:

“5.15    Foreign Subsidiary Voting Rights. No decision or action in any
governing document of any direct or indirect Foreign Subsidiary (other than an
Eligible Foreign Subsidiary) requires a vote of greater than 50.1% of the equity
interests or voting rights of such Foreign Subsidiary.”

(E) Section 7.12 of the Loan Agreement is hereby amended and restated in its
entirety to read as follows:

“7.12    Deposit Accounts. Neither Borrower nor any Subsidiary shall maintain
any Deposit Accounts, or accounts holding Investment Property, except with
respect to which Agent has an Account Control Agreement; provided, however, an
aggregate amount of cash not to exceed $2,000,000 (calculated at current
exchange rates and determined on a US Dollar equivalent basis) may be held in
Deposit Accounts of Savara Denmark at any time.”

(F) A new Section 7.18 is added to Section 7 of the Loan Agreement to read as
follows:

“7.18    Foreign Subsidiary Voting Rights. Borrower shall not, and shall not
permit any Subsidiary, to amend or modify any governing document of any direct
or indirect Foreign Subsidiary (other than an Eligible Foreign Subsidiary) the
effect of which is to require a vote of greater than 50.1% of the equity
interests or voting rights of such entity for any decision or action of such
entity.”

(G) Exhibit G hereto is attached to the Loan Agreement as Exhibit G to the Loan
Agreement for all purposes thereunder.

SECTION 4.    Conditions to this Amendment; Other Agreements.

(A) This Amendment shall become effective only if Borrower has satisfied the
conditions set forth in Section 5 of the Fifth Amendment as of the Effective
Time.

(B) Borrower hereby agrees to use its commercially reasonable efforts to deliver
or cause to be delivered, on or before the date that is 30 days following the
effective date of this Amendment, a duly executed landlord consent and waiver
agreement (or similar agreement) among Agent, Savara Inc. (to be renamed “Aravas
Inc.” following the Merger) and Gateway Las Cimas, LLC.

SECTION 5.    Effect on Loan Documents. Except as specifically amended herein
and the Prior Amendments (as well as any prior amendments to the Warrant as
agreed to in writing between Lender and Borrower), all Loan Documents shall
continue to be in full force and effect and are ratified and confirmed in all
respects. The execution, delivery and effectiveness of this Amendment shall not
operate as a waiver of any right, power or remedy of any Lender or Agent under
any of the Loan Documents, and it shall not constitute a waiver of any provision
of the Loan Documents. Any reference to the Loan Agreement in any other Loan
Document shall be a

 

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reference to the Loan Agreement as amended by this Amendment and the Prior
Amendments. For the avoidance of doubt, all references in the Loan Agreement to
“Mast Therapeutics, Inc.” will mean “Savara Inc.” following the Merger, and,
following the Merger, Savara Inc. and Aravas Inc. will each be Borrowers for all
purposes under the Loan Agreement.

SECTION 6.    Representations and Warranties. Borrower represents and warrants
to Agent and Lender as follows:

(A)    Borrower’s execution, delivery and performance of this Amendment (i) has
been duly authorized by all necessary corporate action of Borrower, (ii) will
not result in the creation or imposition of any Lien upon the Collateral or the
Intellectual Property, other than Permitted Liens and the Liens created by the
Loan Documents, (iii) does not violate any provisions of Borrower’s Certificate
of Incorporation, bylaws, or any law, regulation, order, injunction, judgment,
decree or writ to which Borrower is subject, and (iv) except as described on
Schedule 5.3 to the Loan Agreement, does not violate any contract or agreement
or require the consent or approval of any other Person which has not already
been obtained. The individual or individuals executing this Amendment are duly
authorized to do so.

(B)    This Amendment has been duly executed and delivered on Borrower’s behalf
by a duly authorized officer thereof, and constitutes a legal, valid and binding
obligation of Borrower, enforceable in accordance with its terms, subject to
bankruptcy, reorganization, insolvency, moratorium and other similar laws
affecting the enforcement of creditors’ rights generally and the exercise of
judicial discretion in accordance with general principles of equity.

SECTION 7.    Governing Law. This Amendment shall be governed by, and construed
in accordance with, the law of the State of California.

SECTION 8.    Counterparts. This Amendment may be executed in one or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument. Delivery by facsimile,
.pdf or other electronic imaging means of an executed counterpart of a signature
page to this Amendment shall be effective as delivery of an original executed
counterpart of this Amendment. Agent may also require that any such documents
and signatures delivered by facsimile, .pdf or other electronic imaging means be
confirmed by a manually signed original thereof; provided that the failure to
request or deliver the same shall not limit the effectiveness of any document or
signature delivered by facsimile, .pdf or other electronic imaging means.

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly
executed and delivered by their respective proper and duly authorized officers
as of the day and year first above written.

 

BORROWER: MAST THERAPEUTICS, INC. By:  

/s/ Brandi Roberts

  Name: Brandi Roberts   Title:   Chief Financial Officer AGENT: HERCULES
CAPITAL, INC. By:  

/s/ Jennifer Choe

  Name: Jennifer Choe   Title:   Assistant General Counsel LENDER: HERCULES
TECHNOLOGY III, L.P. By:   Hercules Technology SBIC Management, LLC, its General
Partner By:   Hercules Capital, Inc., its Manager By:  

/s/ Jennifer Choe

  Name: Jennifer Choe   Title:   Assistant General Counsel

 

[Signature Page to Sixth Amendment to Loan and Security Agreement]