Document:

EX-10.19

 Exhibit 10.19 

Confidential Materials omitted and filed separately with the 

Securities and Exchange Commission. Double asterisks denote omissions. 

Execution Copy 
 CONFIDENTIAL

 OPTION AND LICENSE AGREEMENT 

THIS OPTION AND LICENSE AGREEMENT (the
“Agreement”) is made effective as of February 27, 2017 (the “Effective Date”), by and between ADIMAB, LLC, a Delaware limited liability company having an address at 7
Lucent Drive, Lebanon, NH 03766 (“Adimab”), and ARSANIS INC., a Delaware corporation having an address at 890 Winter Street, Suite 230, Waltham, MA 02451-1472
(“Arsanis”). 
 BACKGROUND 

WHEREAS, Adimab has proprietary antibodies against RSV; 

WHEREAS, Arsanis desires to develop, manufacture and commercialize one or more RSV Antibodies against RSV
in accordance with the terms hereof; and 
 NOW, THEREFORE, in consideration of the
foregoing premises and the mutual covenants set forth below, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Adimab and Arsanis hereby agree as follows: 

ARTICLE 1 
 DEFINITIONS.

 The following initially capitalized terms have the following meanings (and derivative forms of them shall be interpreted
accordingly): 
 1.1 “Adimab” has the meaning set forth in the recitals. 

1.2 “Adimab Derived Antibody” has the meaning set forth in Section 1.7(b) (Adimab RSV Antibody). 

1.3 “Adimab Indemnitees” has the meaning set forth in Section 8.2 (Indemnification by Arsanis). 

1.4 “Adimab Materials” means any tangible biological or chemical materials (including all [**] and other [**] in the form of
tangible biological or chemical materials) used or created by Adimab under a previously performed RSV research program, [**]. 
 1.5
“Adimab Platform Patents” means all Patents [**] the [**] that [**]. For clarity, Adimab Platform Patents specifically exclude: (a) RSV Antibody Patents; and (b) any Patents Controlled by Adimab to the extent that they
Cover any invention or subject matter other than the manner in which Adimab discovered the Adimab RSV Antibodies. 

 1.6 “Adimab Platform Technology” means (a) methods of
discovery and optimization of antibodies, which methods include the use of synthetic DNA antibody libraries and engineered strains of yeast and interrogating repertoires generated through B-cell cloning, (b) all methods, materials and other
Know-How used in the foregoing and (c) platforms embodying any of the foregoing in (a) or (b), or components, component steps or other portions thereof; in each case, solely to the extent the foregoing either (i) are Covered by
Patents Controlled by Adimab or (ii) constitute Confidential Information of Adimab. For clarity, Adimab Platform Technology includes technology Controlled by, or confidential or proprietary to, Adimab that is used by Adimab in the discovery and
optimization of any Adimab RSV Antibody, in each case based on the manner in which Adimab discovered or optimized such Adimab RSV Antibody, but not based on the specific composition of or any Sequence information regarding such Adimab RSV Antibody
(or any product containing an Adimab RSV Antibody), but Adimab Platform Technology excludes: (A) Adimab RSV Antibodies; and (B) technology Controlled by, or confidential or proprietary to, Adimab that is related to: (1) product
formulation; (2) manufacturing, purification, or production; (3) modification or optimization of antibodies; (4) RSV (including any antigen representation thereof), or any mechanism of action via interaction with RSV, or methods of
using antibodies based on their interaction with RSV; or (5) if other than an IgG, the construct of any Product. 
 1.7
“Adimab RSV Antibody” means: 
 (a) any RSV-specific antibody discovered or identified by or on behalf of
Adimab, on or before the Effective Date, in any biological material obtained from a Donor, as listed on Exhibit A hereto (each, an “Initial RSV Antibody”); or 

(b) any modified or derivative form of any Initial RSV Antibody (including an scFv or Fab) created by or on behalf of Adimab (whether
before, on, or after the Effective Date), including any fragment or pegylated version (whether or not including amino acid changes) of an Initial RSV Antibody and including chemically modified versions (including associated amino acid substitutions)
of an Initial RSV Antibody, and including an antibody designed or derived using the Sequence of any Initial RSV Antibody, polynucleotide encoding it, and any cell line or cellular or bacterial expression system or vector expressing any Initial RSV
Antibody or incorporating the polynucleotide encoding an Initial RSV Antibody (in each case, an “Adimab Derived Antibody”). For clarity, any modified or derivative form of any Adimab Derived Antibody created by or on behalf
of Adimab shall itself be an Adimab Derived Antibody. 
 1.8 “Administrator” has the meaning set forth in Section
10.4(b)(i) (Arbitration). 
 1.9 “Affiliate” means an entity that, directly or indirectly, through one
or more intermediaries, controls, is controlled by or is under common control with a Party. For this purpose, “control” means the possession, directly or indirectly, of fifty percent (50%) or more of the voting securities entitled to
elect the directors or management of the entity, or of the actual power to elect or direct the management of the entity. 

  
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 1.10 “Agreement” has the meaning set forth in the recitals. 

1.11 “Antibody” means any full-length antibody, fragment thereof, and chemically modified version thereof
(including any pegylated versions and regardless of whether containing amino acid substitutions), all of the foregoing whether naturally occurring, artificially produced, raised in an artificial system, or created through modification of an antibody
produced in any of the foregoing ways or otherwise, and whether represented by physical material, nucleic acid sequences, or amino acid sequences. 

1.12 “Arsanis” has the meaning set forth in the recitals. 

1.13 “Arsanis Approvals” has the meaning set forth in Section 3.6 (Regulatory). 

1.14 “Arsanis Derived Antibody” means any modified or derivative form of an Adimab RSV Antibody (including an
scFv or Fab) created by or on behalf of Arsanis or its Licensees or the Foundation, including any fragment or pegylated version (whether or not including amino acid changes) of an Adimab RSV Antibody and including chemically modified versions
(including associated amino acid substitutions) of an Adimab RSV Antibody, and including an antibody designed or derived using the Sequence of any Adimab RSV Antibody, polynucleotide encoding it, and any cell line or cellular or bacterial expression
system or vector expressing any Adimab RSV Antibody or incorporating the polynucleotide encoding an Adimab RSV Antibody. For clarity, any modified or derivative form of any Arsanis Derived Antibody shall itself be an Arsanis Derived Antibody. 

1.15 “Arsanis Indemnitees” has the meaning set forth in Section 8.1 (Indemnification by Adimab). 

1.16 “Arsanis Invention” means any invention, whether or not patentable, that is made solely by one or more
employees, consultants or contractors of Arsanis in the course and as a result of: (a) the practice of the Research License during the Evaluation Term; or (b) the practice of the License or the discovery, optimization, research,
development, manufacture or commercialization of Arsanis Derived Antibodies or Products during the Post-Exercise Term. 
 1.17
“Arsanis Know-How” shall mean all Know-How Controlled by Arsanis as of the effective date of termination of this Agreement that is necessary or useful for the development, manufacture or commercialization of RSV
Antibodies in the Field, including, without limitation, all data and results of any research, preclinical, clinical, stability, toxicology or other study of any RSV Antibody conducted by or on behalf of Arsanis. 

1.18 “Arsanis Materials” means (a) any tangible biological or chemical materials (including antigen
samples and other Know-How in the form of tangible biological or chemical materials) created by Arsanis in the practice of the Research License or the License or in the development or manufacture of Licensed Antibodies and Products, and
(b) from and after the time of the Option exercise, the quantities of Selected Antibody provided to Arsanis by Adimab under this Agreement. 

1.19 “Arsanis Patents” means Patents Covering Arsanis Inventions. 

  
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 1.20 “Arsanis Regulatory Filings” has the meaning set forth in
Section 3.6 (Regulatory). 
 1.21 “Assignment” has the meaning set forth in Section 3.1(a)
(Assignment). 
 1.22 “Background Technology” has the meaning provided in the Grant Documents. For
clarity, Adimab RSV Antibodies are Background Technology, and will remain Background Technology even if (i) such Adimab RSV Antibodies are assayed or otherwise used in the performance of the Funded Project to generate data (understanding that
such data may be Funded Developments rather than Background Technology) or (ii) Arsanis Derived Antibodies are created from them (understanding that such Arsanis Derived Antibodies may be Funded Developments rather than Background Technology).

 1.23 “Bankruptcy Laws” has the meaning set forth in Section 10.2 (Bankruptcy Code). 

1.24 “Biosimilar” means, with respect to a Product in a country, any pharmaceutical biologic product that
(a) is similar to such Product; (b) has the same route of administration, dosage form and strength as such Product; (c) obtained regulatory approval under a biosimilar application submitted in accordance with the then-current rules
and regulations in such country that referred to or relied on data submitted by Arsanis, or any of its Affiliates or Licensees, in an NDA for the Product in such country; and (d) is sold in the same country as such Product by a Third Party that
is not a Licensee of Arsanis or its Affiliates and did not purchase such product in a chain of distribution that included any of Arsanis or its Affiliates or Licensees. 

1.25 “Blocking Arsanis Patents” shall mean: 

(a) in the case of (i) expiration of this Agreement pursuant to clause (a) of Section 9.1 (Term), or
(ii) termination of this Agreement prior to Option exercise either (A) by Adimab pursuant to Section 9.2 (Termination for Material Breach) or (B) by Arsanis pursuant to Section 9.3 (Termination for Convenience): Arsanis
Patents that, in the absence of a license thereunder, would be infringed by the manufacture, use, sale, offer for sale or import of any RSV Antibody; provided, however, that “Blocking Arsanis Patents” shall exclude any and all
Patents licensed to Arsanis by any Third Party; and 
 (b) in the case of termination of this Agreement during the Post-Exercise Term
either (i) by Adimab pursuant to Section 9.2 (Termination for Material Breach) or (ii) by Arsanis pursuant to Section 9.3 (Termination for Convenience): Arsanis Patents that, in the absence of a license thereunder, would be
infringed by the manufacture, use, sale, offer for sale or import of any Adimab RSV Antibody; provided, however, that “Blocking Arsanis Patents” shall exclude any and all Patents licensed to Arsanis by any Third Party. 

1.26 “CDR” means the complementarity determining regions of an antibody. 

1.27 “Combination Product” means a product containing a Licensed Antibody in combination with one or more Other
Active(s). 

  
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 1.28 “Commercially Reasonable Efforts” means with respect to
Arsanis’ obligation under this Agreement to conduct a particular activity, a level of efforts and resources similar to those efforts and resources normally used by Arsanis for a similar product owned by it or to which it has rights, which
product is at a similar stage in its development or product life and is of similar market potential, based on conditions then prevailing and taking into account safety, efficacy, product profile, the competitiveness of the marketplace, the
proprietary position of the product, the regulatory structure involved, the market potential and profitability of the product, and other relevant scientific, technical and commercial factors. 

1.29 “Companion Diagnostic” means an in vitro diagnostic device consisting of or containing
Licensed Antibody(ies) that provides information for the safe and effective use of a particular therapeutic Product, where the use of such in vitro diagnostic device is stipulated in the instructions for use in the labeling of
both such in vitro diagnostic device and the corresponding therapeutic Product approved by the applicable Regulatory Authority. 

1.30 “Compulsory License” means, in the case of a Product in a country, a compulsory license obtained by a Third Party
through the order, decree or grant of a Regulatory Authority or other governmental authority of such country, authorizing such Third Party to manufacture, use, sell, offer for sale or import such Product in such country. 

1.31 “Confidential Information” has the meaning set forth in Section 6.1(a)
(Confidential Information). 
 1.32 “Control” means, with respect to any Know-How or Patent[**]other than
pursuant to this Agreement[**] of the [**] as provided for in this Agreement without violating the terms of any written agreement with any Third Party. 

1.33 “Cover” or “Covering” or the like, means, with respect to a particular Licensed Antibody or
Product and a particular Patent, that the [**] of such [**] or [**]. 
 1.34 “Disclosing
Party” has the meaning set forth in Section 6.2 (Exclusions from Nondisclosure Obligation). 
 1.35
“Dispute” has the meaning set forth in Section 10.4(a) (Initial Dispute Resolution). 

1.36 “Donor” means either of the human donors identified by Adimab as “patient #[**]” and “patient
#[**].” 
 1.37 “Effective Date” has the meaning set forth in the recitals. 

1.38 “EMA” means the European Medicines Agency or any successor agency thereto in the European Union having
substantially the same function. 
 1.39 “Evaluation Term” means the time period beginning upon the
Effective Date and ending on the earlier of (a) [**] months from the date upon which Adimab has delivered to Arsanis both (i) the Sequences of all Adimab RSV Antibodies and (ii) [**] IgG material of each of the Highest-Affinity
Initial RSV Antibodies, and (b) the date that is [**] days after Arsanis receives funding from the Foundation for the conduct of the Funded Project activities described under “Milestone 3 – Phase 1 ready” in the Grant Documents
which funding is payable upon achievement of “Milestone 2 – Process Lock” as described in the Grant Documents. 

  
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 1.40 “Evaluation Term Data” has the meaning
set forth in Section 2.9 (Effect of Expiration of Option Without Exercise). 
 1.41 “Evaluation Term Patents”
means any application for an Arsanis Patent filed by or on behalf of Arsanis during the Evaluation Term that Covers any Arsanis Derived Antibody and all Arsanis Patents corresponding to such patent application. 

1.42 “Excluded Technology” means Third Party technology (and the Patents that Cover and the Know-How that embodies
such Third Party technology) related to: 
 [**]. 

1.43 “FDA” means the United States Food and Drug Administration or any successor agency thereto in the U.S. having
substantially the same function. 
 1.44 “Field” means all indications and uses;
provided, however, that if Arsanis proposes to commercialize any Product as a diagnostic (other than as a Companion Diagnostic) or as a research reagent, the Parties will first negotiate commercially reasonable financial terms for such field
of use. For clarity: (a) no further negotiation will be required for the development, manufacture, or commercialization of any Companion Diagnostic; (b) Arsanis shall pay royalties with respect to Net Sales of Companion Diagnostics in
accordance with Section 4.3 of this Agreement; (c) no Milestone Payments shall be payable with respect to any Companion Diagnostic; and (d) no other or additional financial terms will apply to the development, manufacture, or
commercialization of any Companion Diagnostic. 
 1.45 “First Commercial Sale” means, with respect to a
Product in any country, the first sale, transfer or disposition for value or for end use or consumption of such Product in such country after Marketing Approval (and, if legally required, pricing approval) for such Product has been received in such
country. 
 1.46 “First Product” has the meaning set forth in Section 4.2(a)
(Milestone Events). 
 1.47 “Force Majeure” means conditions beyond a Party’s reasonable control or
ability to plan for, including acts of God, war, terrorism, civil commotion, labor strike or lock-out; epidemic; failure or default of public utilities or common carriers; and destruction of facilities or materials by fire, earthquake, storm or like
catastrophe. 
 1.48 “Foundation” means the Bill & Melinda Gates Foundation or its designee(s). 

1.49 “Foundation Rights” means the licenses and other rights granted by Arsanis to the Foundation under the Grant
Documents with respect to Funded Developments and any Background Technology incorporated into a Funded Development or required to use a Funded Development. 

  
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 1.50 “FTE” means the equivalent of a full-time employee’s working
days over a twelve (12) month period (taking account of normal vacations, sick days and holidays not being considered working days), which equates to a total of [**] hours per twelve (12) month period of work performed by a fully qualified
Adimab employee or consultant. To provide an FTE over a given period that is less than a year means to provide the proportionate share (corresponding to the proportion that such period bears to a full year) during such period of a full year’s
FTE. 
 1.51 “FTE Rate” means [**] dollars ($[**]) per FTE. 

1.52 “Fully Paid Product” has the meaning set forth in Section 9.5(b)(i)(2)(A)
(Termination But For Fully-Paid Products). 
 1.53 “Funded Developments” has the meaning provided in the Grant
Documents. 
 1.54 “Funded Project” means the project described in the Project Plan incorporated by reference
in the Grant Documents. 
 1.55 “Global Access Commitment” means Arsanis’ obligations described under
the heading “Global Access” in the “Terms and Conditions” included in the Grant Documents. 
 1.56
“Grant Documents” means the Grant Agreement between Arsanis and the Foundation dated as of February 20, 2017, including all Attachments thereto. 

1.57 “Highest-Affinity Initial RSV Antibodies” has the meaning set forth in Section 2.3 (Delivery of Adimab
RSV Antibodies). 
 1.58 “IND” means: (a) in the United States, an Investigational New Drug
application (as more fully described in 21 CFR Part 312, or its successor regulation), filed with the FDA, or any successor application to the foregoing; or (b) in any other country or group of countries, the equivalent application or filing
filed with the governing Regulatory Authority in such country or group of countries necessary to commence human clinical trials in such jurisdiction. 

1.59 “Indemnified Party” has the meaning set forth in Section 8.3 (Indemnification
Procedures). 
 1.60 “Indemnify” has the meaning set forth in Section 8.1
(Indemnification by Adimab). 
 1.61 “Indemnifying Party” has the meaning set
forth in Section 8.3 (Indemnification Procedures). 
 1.62 “Indemnitees”
has the meaning set forth in Section 8.3 (Indemnification Procedures). 
 1.63 “Initial RSV Antibody”
has the meaning set forth in Section 1.7(a) (Adimab RSV Antibody). 

  
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 1.64 “Know-How” means all technical information and know-how in any
tangible or intangible form, including (a) inventions, discoveries, trade secrets, data, specifications, instructions, processes, formulae, materials (including cell lines, vectors, plasmids, nucleic acids and the like), methods, protocols,
expertise and any other technology, including the applicability of any of the foregoing to formulations, compositions or products or to their manufacture, development, registration, use or marketing or to methods of assaying or testing them or
processes for their manufacture, formulations containing them or compositions incorporating or comprising them, and (b) all data, instructions, processes, formulae, strategies, and expertise, whether biological, chemical, pharmacological,
biochemical, toxicological, pharmaceutical, physical, analytical, or otherwise and whether related to safety, quality control, manufacturing or other disciplines; that, in each case, are not in the public domain. Notwithstanding the foregoing,
Know-How excludes Patent claims. 
 1.65 “License” has the meaning set forth in Section 3.1(b)
(License). 
 1.66 “Licensed Antibody” means: (a) any Selected Antibody; or (b) any
Arsanis Derived Antibody created from any Selected Antibody, whether before or after exercise of the Option. 
 1.67
“Licensee” means a Third Party to whom Arsanis or its Affiliate has granted, directly or indirectly through one or more tiers of sublicense, a license, sublicense or other right to develop, manufacture, and/or commercialize any
Licensed Antibody or Product; but specifically excluding (a) the Foundation and (b) any Third Party contract service provider. For clarity, licensees of RSV Antibody Patents and sublicensees of the License (excluding, in each case, the
Foundation) shall be Licensees. 
 1.68 “Licensee Agreement” has the meaning set forth in Section 3.2
(Licensees and Sublicensees). 
 1.69 “Losses” has the meaning set forth in Section 8.1
(Indemnification by Adimab). 
 1.70 “Major European Market” means any of [**]. 

1.71 “Major Market” means any of the [**]. 

1.72 “Marketing Approval” means, within any given country, approval to market and sell a Product legally as a drug or
biologic, including approval of an NDA. Pricing approval need not be obtained in order for Marketing Approval to be achieved. 

1.73 “Milestone Event” has the meaning set forth in Section 4.2(a) (Milestone Events).

 1.74 “Milestone Payment” has the meaning set forth in Section 4.2(a) (Milestone
Events). 

  
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 1.75 “NDA” means: (a) in the United States, as
applicable, a New Drug Application (as more fully described in 21 CFR Part 314.50, et seq., or its successor regulation) or a Biologics License Application (as more fully described in 21 CFR Part 601, et seq., or its successor regulation), filed
with the FDA, or any successor application to either of the foregoing; or (b) in any other country or group of countries, the equivalent application or submission for approval to market a pharmaceutical product filed with the governing
Regulatory Authority in such country or group of countries. 
 1.76 “Net Sales” means the gross amounts invoiced for
sales or other dispositions of Products (including Companion Diagnostics) by or on behalf of Arsanis, its Affiliates and Licensees, and to the extent such sales or other dispositions are not NGO Sales, the Foundation (each, a “Selling
Party”) to Third Parties (other than a Selling Party), less the following deductions actually incurred, allowed, paid, accrued or otherwise specifically allocated to Products by the Selling Party (if not previously deducted in calculating
the amount invoiced), all in compliance with applicable accounting standards, consistently applied by the Selling Party: 

[**]. 
 NGO Sales
shall not be deemed sales or other dispositions of Products for purposes of this definition of “Net Sales” or for purposes of Article 4 (Financial Terms) hereof except to the extent set forth in Section 1.77 (NGO
Sales’). 
 For clarity, sale of a Product by a Selling Party to another Selling Party for resale by such entity to a Third Party
(other than a Selling Party) shall not be deemed a sale for purposes of this definition of “Net Sales,”; provided, however, that the first sale thereafter by a Selling Party to a Third Party (other than a Selling Party) shall be included
in the computation of Net Sales. If a Selling Party sells or disposes of a Product to a Third Party (other than a Selling Party) in a country in a transaction that is not an arm’s-length sale (defined below), the gross amount invoiced for such
Product for purposes of calculating Net Sales for such transaction shall be deemed to equal the weighted (by sales volume) average sale price of such Product in such country to arm’s-length purchasers during the calendar quarter in which such
sale or disposition occurs. For purposes of the foregoing, an “arm’s-length sale” is a sale of Product solely for cash consideration to a Third Party that is unaffiliated with the Selling Party. 

Further, transfers or dispositions of Products as free promotional samples in commercially reasonable amounts, consistent with prevailing
pharmaceutical industry standards, or in any patient assistance, test marketing program, named-patient program or compassionate use program (so long as such Products are provided without charge or at or below the Selling Party’s cost), donated
to non-profit institutions or government agencies, or used in research, development or regulatory activities, including, without limitation, clinical trials, shall be disregarded in determining Net Sales. 

On a country-by-country basis, if a Product under this Agreement is sold in the form of a Combination Product in a country, Net Sales for the
purpose of determining royalties due hereunder shall be calculated as follows: 
 (i) Where both Product containing the applicable
Licensed Antibody as its sole active therapeutic ingredient (“Single-Agent Product”) and all Other Active(s) in such Combination Product are sold separately in such country, Net Sales shall be calculated by multiplying
actual Net Sales of such Combination Product in such country (as determined 

  
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without the application of this paragraph) by the fraction A/(A+B), where A is the weighted average sale price (by sales volume) of Single-Agent Product in such country, and B is the weighted
average sale price (by sales volume) of the Other Active(s) in the Combination Product when sold separately, in each case in the same dosage and dosage form and in the same country as the Combination Product during the applicable reporting period.

 (ii) If Single-Agent Product is sold in such country, but none of the Other Active(s) is sold separately in such country, Net
Sales shall be calculated by multiplying actual Net Sales of such Combination Product in such country (as determined without the application of this paragraph) by the fraction A/C, where A is the weighted average sale price (by sales volume) of such
Single-Agent Product in such country, and C is the weighted average sale price (by sales volume) of the Combination Product in such country. 

(iii) If Single-Agent Product is not sold in such country, but the Other Active(s) are sold separately in such country, Net Sales
shall be calculated by multiplying actual Net Sales of such Combination Product in such country (as determined without the application of this paragraph) by the fraction (C-D)/C, where C is the weighted average sale price (by sales volume) of the
Combination Product in such country, and D is the sum of the weighted average sale price (by sales volume) of the Other Active(s) in the Combination Product when sold separately in such country. 

(iv) If neither Single-Agent Product nor the Other Active(s) are sold separately in such country, Net Sales for the purpose of
determining royalties due hereunder for the Combination Product shall be determined by mutual agreement of the Parties in good faith based on the relative value contributions of the Licensed Antibody and the Other Active(s), such agreement not to be
unreasonably withheld. If the Parties are unable to reach mutual agreement as to the relative value contributions of the Licensed Antibody and the Other Active(s), such relative value contributions shall be determined in accordance with Section 10.4
(Dispute Resolution). 
 1.77 “NGO Sales” means sales and dispositions of Products (including Companion
Diagnostics) by or on behalf of the Selling Parties in fulfillment of the Global Access Commitment, to the extent that the gross amounts invoiced and the fair market value of non-cash consideration received by the Selling Parties for such sales and
dispositions of Products does not exceed the sum of: (a) the Selling Party’s fully-burdened cost of goods of such Products; (b) excise taxes, use taxes, tariffs, sales taxes and customs duties and/or other government charges or fees
imposed on the sale of such Products (including VAT); and (c) outbound freight, shipment, insurance and other distribution costs for such Products. For clarity, to the extent that the gross amounts invoiced and the fair market value of non-cash
consideration received by the Selling Parties for sales and dispositions of Products (including Companion Diagnostics) in fulfillment of the Global Access Commitment exceed the sum of (a), (b) and (c) in the foregoing sentence, the amount
of such excess shall be included in the calculation of “Net Sales” (and shall not be considered “NGO Sales”). 

1.78 “Option” has the meaning set forth in Section 2.2(b) (Option). 

1.79 “Option Fee” has the meaning set forth in Section 4.1(b) (Option Fee). 

  
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 1.80 “Other Active” means any active therapeutic ingredient other than a
Licensed Antibody. 
 1.81 “Other Arsanis Patents” means all Arsanis Patents (other than Blocking Arsanis
Patents) that claim inventions actually practiced by or on behalf of Arsanis in the manufacture, use, sale, offer for sale or import of any RSV Antibody prior to termination of this Agreement. 

1.82 “Party” means Adimab or Arsanis. 

1.83 “Patent” means any patent application or patent anywhere in the world, including all of the following categories
of patents and patent applications, and their foreign equivalents: provisional, utility, divisional, continuation, continuation-in-part, and substitution applications; and utility, re-issue, re-examination, renewal and extended patents; and any
rights associated with extended patent terms, including Patent Term Adjustment (PTA), Patent Term Extension (PTE), Supplementary Protection Certificates (SPC); and other similar rights. 

1.84 “Phase I Trial” means a human clinical trial conducted in any country that would satisfy the requirements for a
Phase 1 study as defined in 21 CFR § 312.21(a) (or any amended or successor regulations). 
 1.85 “Phase II
Trial” means a human clinical trial conducted in any country that would satisfy the requirements for a Phase 2 study as defined in 21 CFR § 312.21(b) (or any amended or successor regulations). 

1.86 “Phase III Trial” means a human clinical trial conducted in any country that would satisfy the requirements for a
Phase 3 study as defined in 21 CFR § 312.21(c) (or any amended or successor regulations). 
 1.87 “PMDA”
shall mean the Japanese Pharmaceuticals and Medical Devices Agency or any successor agency thereto in Japan having substantially the same function. 

1.88 “Post-Exercise Term” means the portion of the Term beginning upon Arsanis’ exercise of the Option in
accordance with Section 2.2(b) (Option). 
 1.89 “Product” means any pharmaceutical product
(whether or not such product has received Marketing Approval) that comprises or contains one or more Licensed Antibodies (whether or not as the sole active ingredient(s)), including, without limitation, any Companion Diagnostic. 

1.90 “Receiving Party” has the meaning set forth in Section 6.2 (Exclusions from Nondisclosure
Obligation). 
 1.91 “Regulatory Authority” shall mean any national, supranational or other regulatory
agency, department, bureau or other governmental or regulatory authority having the administrative authority to regulate the development or marketing of pharmaceutical products in any country or other jurisdiction, including the FDA in the U.S., the
EMA in the European Union, and the PMDA in Japan. 

  
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 1.92 “Research License” has the meaning set forth in Section 2.2(a)
(Research License to Arsanis). 
 1.93 “Research Plan” has the meaning set forth in Section 2.3
(Delivery of Adimab RSV Antibodies). 
 1.94 “Royalty Payment” has the meaning set forth
in Section 4.3(a) (Royalty Payments). 
 1.95 “Royalty Term” means, on a
Product-by-Product and country-by-country basis, the term beginning on First Commercial Sale of a Product in a country and ending at the later of twelve (12) years after the First Commercial Sale of such Product in such country and (b) the
expiration of the last Valid Claim of an RSV Antibody Patent listed on Exhibit B hereto (or a Patent claiming priority to an RSV Antibody Patent listed on Exhibit B hereto) Covering such Product in such country. 

1.96 “RSV” means respiratory syncytial virus. 

1.97 “RSV Antibodies” means, collectively, Adimab RSV Antibodies and Arsanis Derived Antibodies. 

1.98 “RSV Antibody Patents” means those Patents that Cover Adimab RSV Antibodies, including those Patents set forth on
Exhibit B hereto. RSV Antibody Patents exclude: (a) Adimab Platform Patents; and (b) those Patents that Cover Arsanis Derived Antibodies (except to the extent any claim of any such Patent claims priority to any of the Patents set
forth on Exhibit B hereto). 
 1.99 “Rules” has the meaning set forth in Section 10.4(b)(i)
(Arbitration). 
 1.100 “Sale Transaction” has the meaning set forth in Section 10.7
(Assignment). 
 1.101 “Second Product” has the meaning set forth in Section 4.2(a)
(Milestone Events). 
 1.102 “Selected Antibody” has the meaning set forth in Section 2.2(b)
(Option). 
 1.103 “Selling Party” has the meaning provided in Section 1.766 (Net
Sales). 
 1.104 “Senior Executive Discussions” has the meaning set forth in Section 10.4(a)
(Initial Dispute Resolution). 
 1.105 “Sequence” means, with respect to any Antibody,
the amino acid sequence of such Antibody and the corresponding nucleic acid sequences encoding such Antibody. 
 1.106
“Single Agent Product” has the meaning set forth in Section 1.76 (Net Sales). 
 1.107
“Term” shall have the meaning set forth in Section 9.1 (Term). 
 1.108 “Third
Party” means an entity other than a Party or a Party’s Affiliates. 

  
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 1.109 “Third Party Acquirer” has the meaning set forth in Section 10.7
(Assignment). 
 1.110 “Third Party Claims” has the meaning
set forth in Section 8.1 (Indemnification by Adimab). 
 1.111 “Third Party Patent License” means a license
under a Patent of a Third Party that Arsanis determines in good faith is reasonably required for the manufacture, use, sale, offer for sale or import of a Licensed Antibody or Product in order to avoid potential Third Party claims of patent
infringement based on the way in which Adimab discovered an Adimab RSV Antibody using Adimab Platform Technology. For clarity, Third Party Patent Licenses explicitly excludes (a) licenses to any Patent other than a Patent Covering the way in
which an Adimab RSV Antibody was discovered using Adimab Platform Technology and (b) licenses to Excluded Technology. 

1.112 “Unrestricted RSV Antibody” means any RSV-specific antibody that is not an RSV Antibody. 

1.113 “Valid Claim” means a claim of a Patent, which claim (a) is issued and unexpired and has not been found to
be unpatentable, invalid or unenforceable by a court or other authority having jurisdiction, from which decision no appeal is taken, will be taken or can be taken; or (a) is pending and has not been finally abandoned or finally rejected and has
been pending for no more than seven (7) years. 
 1.114 References in the body of this Agreement to “Sections” or
“Articles” refer to the sections or articles of this Agreement. The terms “include,” “includes,” “including” and derivative forms of them shall be deemed followed by the phrase “without limitation”
regardless of whether such phrase appears there (and with no implication being drawn from its inconsistent inclusion or non-inclusion) and the term “or” has the inclusive meaning represented by the phrase “and/or” (regardless of
whether it is actually written and drawing no implication from the actual use of the phrase “and/or” in some instances but not in others). 

ARTICLE 2 
 RESEARCH
LICENSE AND OPTION; EVALUATION OF RSV ANTIBODIES. 
 2.1 Alliance Managers. Each Party shall designate in writing within [**]
days after the Effective Date an “Alliance Manager” to be the primary contact for such Party. A Party may replace its Alliance Manager at any time upon written notice to the other Party. The Alliance Managers shall be responsible for
managing communications between the Parties with respect to this Agreement. 
 2.2 Grants to Arsanis During Evaluation
Term. 
 (a) Research License to Arsanis. Subject to the terms and conditions of this Agreement, Adimab hereby grants
Arsanis, during the Evaluation Term, an exclusive, fully-paid, royalty-free, non-sublicensable license under the Adimab Platform Patents, Adimab Platform Technology, and RSV Antibody Patents, to create, research, optimize, make, have made and use
RSV Antibodies, including Arsanis Derived Antibodies, in the Field for the purposes of (i) determining whether to exercise the Option and (ii) identifying the Adimab RSV Antibodies (if any) with respect to which Arsanis wishes to exercise the
Option (the “Research License”). For the avoidance of doubt, the Research License specifically excludes the right to use the Adimab Platform Technology to discover or optimize antibodies. 

  
 - 13 - 

 (b) Option. Adimab hereby grants to Arsanis, during the Evaluation Period, the
exclusive option (the “Option”) to obtain the Assignment and License for up to [**] Adimab RSV Antibodies selected by Arsanis in its sole discretion. Arsanis may exercise the Option at any time on or before the expiry of the
Evaluation Term by delivering written notice to Adimab identifying the Adimab RSV Antibodies with respect to which Arsanis is exercising the Option (each, a “Selected Antibody”), not to exceed [**] Selected Antibodies, no later than
the expiry of the Evaluation Term, and paying the Option Fee to Adimab within [**] days after delivery of such notice. 
 2.3 Delivery of
Adimab RSV Antibodies. As promptly as practicable (and in any event within [**] days) after the Effective Date, Adimab shall deliver to Arsanis: (a) [**]. It is understood and agreed that [**] and [**], the [**] an Adimab RSV Antibody. In
addition, as promptly as reasonably practicable after the Effective Date, [**], and the [**], by mutual agreement of the Parties. [**] a written research plan for the [**] (the “Research Plan”), which shall set forth the [**]
described therein, and each Party shall [**]. Adimab shall [**]. If [**], Adimab will [**]. 
 2.4 Reports. During the
Evaluation Period, Arsanis shall provide [**] written reports to Adimab summarizing the research and development activities conducted by or on behalf of Arsanis with respect to RSV Antibodies during the preceding [**] period. In addition, such
report shall identify any stage completion milestone of the Funded Project that was achieved during such [**] period. For the avoidance of doubt, in no event shall Arsanis have any obligation to disclose to Adimab the Sequence of any Arsanis Derived
Antibody. 
 2.5 Adimab Materials. 

(a) Use of Adimab Materials During Evaluation Term. During the Evaluation Term, Arsanis shall use the Adimab Materials solely within
the scope of the Research License. Arsanis shall not use Adimab Materials for any other purposes. During the Evaluation Term, Arsanis shall not sell, transfer, disclose or otherwise provide access to the Adimab Materials, other Confidential
Information of Adimab, or RSV Antibodies to any Third Party, except as expressly permitted by Section 2.5(b) (Access to Adimab Materials Within Arsanis) and 2.5(c) (Third Party Access to Adimab Materials). 

(b) Access to Adimab Materials Within Arsanis. Arsanis may allow access to Adimab Materials, other Confidential Information of Adimab,
and RSV Antibodies to those employees, officers and consultants of Arsanis who require such access in order to enable Arsanis to conduct activities with respect to the RSV Antibodies within the scope of the Research License for the purpose of
determining whether to exercise the Option and identifying the Adimab RSV Antibodies (if any) with respect to which Arsanis wishes to exercise the Option; provided, however, that: (i) each such employee, officer or consultant is bound by
obligations of confidentiality and non-use regarding Confidential Information of Adimab, 

  
 - 14 - 

 
ownership, use and disposition of RSV Antibodies, including Adimab Materials, that, in each case, are no less protective of Adimab than the terms of this Agreement; and (ii) Arsanis shall at
all times be fully responsible for its employees’, officers’ and consultants’ compliance with this Agreement. 
 (c) Third
Party Access to Adimab Materials. Arsanis may engage Third Party contractors to perform activities within the scope of the Research License on behalf of Arsanis; provided, however, that: (i) none of Adimab’s rights
hereunder are diminished or otherwise adversely affected as a result of such contracting; (ii) each such contractor undertakes in writing obligations of confidentiality and non-use regarding Confidential Information of Adimab, ownership,
disposition, and use of RSV Antibodies, including Adimab Materials, that, in each case, are no less protective of Adimab than the terms of this Agreement; (iii) prior to initiating performance of any such activities on behalf of Arsanis, each
such contractor has signed a binding agreement or instrument assigning, and agreeing to assign, to Arsanis all data and other work product relating to Adimab Materials and RSV Antibodies generated by such contractor; and (iv) Arsanis shall at
all times be fully responsible for each such contractor’s compliance with this Agreement. 
 (d) Limits on Use of
Adimab Materials. Arsanis understands and agrees that Adimab Materials may have unpredictable and unknown chemical properties, that they are to be used with caution, and that, except as expressly permitted by Article 3 (License and
Assignment; Development & Commercialization) following exercise of the Option, they are not to be used [**]. At no time shall the physical Adimab Materials delivered by Adimab to Arsanis be [**] for any purpose. Arsanis shall use Adimab
Materials in compliance with all applicable laws and regulations. 
 2.6 Title to Adimab Materials. During the Evaluation
Term, Adimab shall retain title to the Adimab Materials, including all quantities of Adimab RSV Antibodies delivered to Arsanis. 

2.7 Adimab Retained Rights. 

(a) Adimab Platform Technology. Adimab will at all times retain the exclusive and absolute right to practice and license the Adimab
Platform Technology and the Adimab Platform Patents for any and all purposes; provided, however, that during the Evaluation Term and the Post-Exercise Term, Adimab shall not deliver Adimab RSV Antibodies to any Third Party. For clarity,
during the Evaluation Term, Adimab may use the Adimab Platform Technology to discover, optimize, develop, manufacture, and commercialize Unrestricted RSV Antibodies on behalf of itself or Third Parties without limitation. Except as set forth in this
Section 2.7(a) (Adimab Platform Technology), nothing herein shall prevent Adimab from licensing or transferring some or all of the Adimab Platform Technology to a Third Party (including technical support in connection therewith) nor shall
anything herein require Adimab to in any way limit the use of the Adimab Platform Technology by Adimab or a Third Party for purposes of generating antibodies against RSV. 

  
 - 15 - 

 (b) Antibodies within Libraries. Notwithstanding anything to the contrary in this
Agreement, nothing herein shall require Adimab to physically remove from its antibody libraries any RSV Antibody that is included in any antibody library it has generated or will generate. Arsanis acknowledges that Adimab has transferred antibody
libraries to numerous partners and may transfer additional antibody libraries to partners in the future, and that although statistically unlikely, it is theoretically possible that such antibody libraries contain antibodies with the same Sequence as
an RSV Antibody. Adimab hereby reserves the right for Adimab to license or transfer any antibody library to Third Parties (including the transfer of physical possession of such antibody libraries, which may contain samples of an RSV Antibody
included therein, to a Third Party as part of the transfer of libraries). 
 (c) Clarifications. For clarity, nothing contained in
this Agreement shall be construed to prohibit or restrict Adimab from: 
 (i) using the Adimab Platform Technology to discover,
optimize, develop, manufacture, and commercialize Unrestricted RSV Antibodies on behalf of itself or Third Parties; 
 (ii)
licensing or transferring any Unrestricted RSV Antibody (including the transfer of physical possession of samples of any Unrestricted RSV Antibody) to any Third Party; 

(iii) using or generating libraries which may include RSV Antibodies, subject to Adimab’s compliance with Section 2.8(a)
(Adimab Negative Covenants); or 
 (iv) licensing or transferring antibody libraries to any Third Party (including samples of
any RSV Antibody contained in such libraries, but solely as contained in such libraries), subject to Adimab’s compliance with Section 2.8(a) (Adimab Negative Covenants). 

2.8 Certain Negative Covenants. The following covenants are in addition to any express covenants of the parties contained elsewhere in
this Agreement. 
 (a) Adimab Negative Covenants. During the Evaluation Term, Adimab and its Affiliates shall not grant
to any Third Party any license, option or other right under or with respect to any RSV Antibody Patent and shall not deliver any isolated Adimab RSV Antibody to any Third Party. Adimab further covenants that, during the Evaluation Term, if any Third
Party to which Adimab or its Affiliate has transferred any antibody library that includes any Adimab RSV Antibody requests, or inquires as to the availability of, any license, option or other rights to any Adimab RSV Antibody, or requests the
nucleic acid sequence or amino acid sequence of any Adimab RSV Antibody, or requests additional physical material of any Adimab RSV Antibody, Adimab or its Affiliate shall: 

(i) inform such Third Party that rights to such Adimab RSV Antibody are not available and that Adimab’s contractual obligations to
another Adimab partner prohibit it from providing the sequence information for, or any additional physical material of, such Adimab RSV Antibody; 

(ii) not disclose to such Third Party the Sequence information (to the extent that such sequence has not been published) for such
Adimab RSV Antibody (it being understood that such Third Party may determine the Sequence of such Adimab RSV Antibody on its own initiative, and the same shall not constitute a breach of this Agreement by Adimab); and 

  
 - 16 - 

 (iii) not deliver any additional physical material of such Adimab RSV Antibodies to a
Third Party. 
 (b) Arsanis Negative Covenants. Arsanis and its Affiliates shall not file any IND with respect to or conduct
any clinical trial of any RSV Antibody during the Evaluation Term prior to Option exercise. Arsanis further covenants not to practice, and not to permit or cause any of its Affiliates or any Licensee or other Third Party to practice, any Adimab
Platform Patents, Adimab Platform Technology or RSV Antibody Patents or Evaluation Term Patents for any purpose outside the express scope of the Research License during the Evaluation Term prior to Option exercise. 

2.9 Effect of Expiration of Option Without Exercise. If the Evaluation Term expires without Arsanis having exercised the Option,
then: 
 (a) effective as of such expiration, (i) the Research License and the Option shall terminate and be of no
further force or effect, and (ii) [**]; and 
 (b) within [**] days after expiration of the Evaluation Term, Arsanis shall
(i) either return to Adimab or destroy (at Adimab’s direction) all quantities of Adimab RSV Antibodies (including Adimab Materials) remaining in the possession of Arsanis, (ii) destroy all quantities of Arsanis Derived Antibodies
remaining in the possession of Arsanis, and (iii) deliver to Adimab [**]. 
 Additional consequences of expiration of the Evaluation
Term without Arsanis having exercised the Option are set forth in Article 9 (Term; Termination) hereof. 
 ARTICLE 3 

LICENSE AND ASSIGNMENT; DEVELOPMENT & COMMERCIALIZATION 

3.1 Development and Commercialization License and Assignment. 

(a) Assignment. Subject to the terms and conditions of this Agreement, effective on Arsanis’ exercise of the Option, Adimab
hereby assigns to Arsanis all right, title and interest in and to all Selected Antibodies and all RSV Antibody Patents (the “Assignment”). 

(b) License. Subject to the terms and conditions of this Agreement, effective on Arsanis’ exercise of the Option, Adimab hereby
grants to Arsanis a non-exclusive, worldwide license, including the right to sublicense through multiple tiers of sublicense in accordance with Section 3.2 (Licensees and Sublicensees), under the Adimab Platform Patents and
Adimab Platform Technology, to research, develop, have developed, make, have made, use, sell, have sold, offer for sale, import and export Licensed Antibodies and Products in the Field (the “License”) during the Term. For the
avoidance of doubt, the License specifically excludes the right to use the Adimab Platform Technology to discover or optimize antibodies. 

  
 - 17 - 

 3.2 Licensees and Sublicensees. Arsanis shall have the right to grant licenses or
sublicenses, through multiple tiers of sublicense, under the License and/or the RSV Antibody Patents, in each case solely with respect to any Licensed Antibody or Product. Any license or sublicense (or option to license or sublicense) of any
Licensed Antibody or Product granted to any Licensee, and any direct or indirect license or sublicense (or option to license or sublicense) under the License and/or the RSV Antibody Patents granted to any Licensee, shall be made solely pursuant to a
written agreement (a “Licensee Agreement”) that is consistent with all relevant terms and conditions of this Agreement and that includes the applicable Licensee’s express agreement to comply with all applicable terms of this
Agreement, including, for clarity, Section 9.4 (Commitments Regarding RSV Antibodies). Arsanis shall remain responsible for all payments and other performance obligations due under this Agreement, notwithstanding any license or
sublicense that it may grant. 
 3.3 Additional Covenants. The provisions of Section 2.8(a) (Adimab Negative
Covenants) shall apply, mutatis mutandis, during the Post-Exercise Term. Arsanis covenants not to practice, and not to permit or cause any of its Affiliates or any Licensee or other Third Party to practice:
(a) any Adimab Platform Patents or Adimab Platform Technology for any purpose outside the express scope of the License; or (b) the RSV Antibody Patents, and Arsanis Patents that Cover Arsanis Derived Antibodies (and solely with respect to
the claims of such Arsanis Patents that Cover Arsanis Derived Antibodies), for the purpose of researching, developing, manufacturing or commercializing RSV Antibodies that are not Licensed Antibodies. 

3.4 Acknowledgment Regarding Arsanis Derived Antibodies. Arsanis hereby acknowledges and agrees that, regardless of whether or not any
of the manufacture, use, sale, offer for sale and import of an Arsanis Derived Antibody is Covered by, or would require the practice of, or a license under, any Adimab Platform Technology, Adimab Platform Patents or RSV Antibody Patents, all Arsanis
Derived Antibodies, and all Products comprising or containing any Arsanis Derived Antibody, developed or commercialized by or on behalf of Arsanis or any of its Affiliates or Licensees, whether during or after the Term, and whether or not any such
Arsanis Derived Antibody is a Licensed Antibody, are milestone- and royalty-bearing to Adimab in accordance with Article 4 of this Agreement; provided, however, that the foregoing shall not be construed as granting to Arsanis
any license or other right under any Adimab Platform Technology, Adimab Platform Patents or RSV Antibody Patents, or any other Patents or Know-How Controlled by Adimab, to develop or commercialize any RSV-specific antibody other than as expressly
permitted by this Agreement. 
 3.5 Diligence. During the Post-Exercise Term, Arsanis (directly or through its Affiliates or
Licensees) shall use Commercially Reasonable Efforts: (a) to [**]; (b) to [**]; (c) to [**]; and (d) following [**]. 

3.6 Regulatory. During the Post-Exercise Term, Arsanis (itself or with or through its Affiliates or Licensees) shall be solely
responsible for preparing and submitting all INDs, NDAs and other regulatory filings for Licensed Antibodies and Products in the Field (collectively, “Arsanis Regulatory Filings”), and for obtaining and maintaining all Marketing
Approvals for Products in the Field (“Arsanis Approvals”), at Arsanis’ sole expense. All Arsanis Regulatory Filings and Arsanis Approvals shall be submitted in the name of, and owned by, Arsanis (or its Affiliate or Licensee,
as applicable). 

  
 - 18 - 

 3.7 Disclosure Regarding Arsanis Efforts. After Arsanis’ exercise of the Option:
(a) prior to [**] of a Product, Arsanis shall provide [**] written reports to Adimab in [**] of each year summarizing the [**]; and (b) after [**] of a Product, Arsanis shall provide [**] written reports to Adimab in [**] of each year
summarizing the [**]. In addition, any such report shall identify any stage completion milestone of the Funded Project that was achieved during the applicable [**]month period. 

3.8 Acknowledgment of Foundation Rights. Adimab acknowledges that Arsanis’ activities under Article 2 and, if Arsanis exercises
the Option, certain activities of Arsanis under this Article 3 constitute part of the Funded Project. Adimab further acknowledges that the funding provided by the Foundation to Arsanis for the Funded Project entitles the Foundation to the Foundation
Rights and makes the Funded Developments and any Background Technology incorporated into a Funded Development or required to use a Funded Development subject to the Global Access Commitment both during and after the Term, regardless of whether or
not Arsanis exercises the Option and notwithstanding the expiration or any termination of this Agreement. 
 ARTICLE 4 

FINANCIAL TERMS. 
 4.1
Pre-Clinical Fees 
 (a) Research Funding. Arsanis shall compensate Adimab on a calendar quarterly basis for Adimab’s
performance of its obligations under, and in accordance with, the Research Plan, in an amount determined by multiplying the actual FTEs expended by Adimab in the performance of such obligations during such calendar quarter by the FTE Rate. Adimab
shall issue quarterly written invoices to Arsanis setting forth the actual FTEs expended by Adimab in performing such Research Plan obligations, which invoice shall describe the Research Plan activities performed, and Arsanis shall pay the invoiced
amount within [**] days of receipt. 
 (b) Option Fee. In order to exercise the Option under Section 2.2(b) (Option),
Arsanis shall pay to Adimab a non-creditable, nonrefundable option exercise fee of [**] dollars ($[**]) (the “Option Fee”). 

4.2 Milestone Payments. 

(a) Milestone Events. Subject to Section 4.2(b) (Maximum Milestone Payments) and Section 4.2(c) (Catch-Up Payments),
Arsanis shall report in writing to Adimab the first achievement of each event set forth in the table below (each, a “Milestone Event”) by (i) the first Product (excluding any Companion Diagnostic) to achieve such Milestone
Event (“First Product”) and (ii) the first Product (excluding any Companion Diagnostic) containing or incorporating a Licensed Antibody other than the Licensed Antibody contained or incorporated in the First Product
(“Second Product”), and, in each case, pay the corresponding milestone payment set forth in the table below (each, a “Milestone Payment”) to Adimab, each within [**] days after the first achievement of the
corresponding Milestone Event by such Product: 

  
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	 Milestone Event
	  	 Milestone Payment

	 	  	 First Product
	  	 Second Product

			
	 [**]
	  	[**]	  	[**]
			
	 [**]
	  	[**]	  	[**]
			
	 [**]
	  	[**]	  	[**]
			
	 [**]
	  	[**]	  	[**]
			
	 [**]
	  	[**]	  	[**]
			
	 [**]
	  	[**]	  	[**]

 (b) Maximum Milestone Payments. For clarity, the maximum aggregate amount of Milestone Payments
payable under this Section 4.2 (Milestone Payments) for any and all Products is twenty four million three hundred seventy five thousand dollars ($24,375,000) (i.e., a maximum aggregate of [**] dollars ($[**]) for the first achievement
of all Milestone Events by the First Product, and a maximum aggregate of [**] dollars ($[**]) for the first achievement of all Milestone Events by a Second Product). 

(c) Catch-Up Payments. If a later-stage clinical Milestone Event is achieved for any Product without one or more earlier-stage clinical
Milestone Events having been achieved for that Product, then Arsanis shall pay the Milestone Payment(s) for such previous clinical Milestone Event(s) along with the payment for the most recently achieved clinical-stage Milestone Event. If a
Milestone Event related to [**] for any Product is achieved without one or more of the clinical Milestone Events being achieved for that Product, then Arsanis shall pay the Milestone Payment(s) for such previous clinical Milestone Event(s) along
with the payment for the first Milestone Event related to filing of an NDA for such Product. 
 4.3 Royalties. 

(a) Royalty Payments. Subject to the remainder of Section 4.3 (Royalties), Arsanis shall pay Adimab, on a
Product-by-Product and country-by-country basis, a royalty of [**] percent ([**]%) of Net Sales of a Product in a country during the applicable Royalty Term for such Product in such country (“Royalty Payments”). On a
Product-by-Product and country-by-country basis, upon expiration of the Royalty Term with respect to a Product in a country, the License with respect to such Product in such country shall become royalty-free, fully-paid, irrevocable and perpetual.

 (b) Adjustment for Third Party IP. If Arsanis enters into any Third Party Patent License, then [**] percent ([**]%) of the
royalties actually paid to the Third Party under such Third Party Patent License with respect to sales of any given Product in any given calendar quarter in any given country may be offset against the Royalty Payment, if any, that would otherwise
have been payable to Adimab with respect to Net Sales of such Product in such calendar quarter in such country; provided, however, that in no event shall the royalty owed to Adimab be reduced by more than [**] percent ([**]%) of the payment
which would otherwise be due hereunder by reason of any and all such offsets in the aggregate. It is understood, agreed and acknowledged that Adimab’s allowing Arsanis to claim the credit of this Section 4.3(b)

  
 - 20 - 

 
(Adjustments for Third Party IP) as to any particular Third Party Patent License: (i) does not mean Adimab believes that the licensed Patents of the Third Party were infringed by or
Cover any aspect of the discovery or optimization work by Adimab; and (ii) is not, will not be, and shall not be under any circumstances construed as an admission of any kind. Adimab may have many reasons not to challenge any given assertion of
the credit of this Section 4.3(b) (Adjustment for Third Party IP) by Arsanis, including: (1) maintaining good relations with a counterparty; (2) an assessment that the costs of the credit are outweighed by the benefits of Arsanis
having a license in place that makes it feel comfortable to proceed with the Product (resulting in a greater likelihood of milestones and royalties being paid to Adimab); (3) resource limitations that make it impracticable to challenge
Arsanis’ assertion of such credit even though Adimab may disagree whether this is proper; and (4) other reasons other than thinking that the relevant Patents Cover or were infringed by any aspect of the discovery or optimization work. 

(c) Biosimilar Competition. On a Product-by-Product and country-by-country basis, if, during the Royalty Term for a Product in a
country, sales of Biosimilars of such Product account for [**]% or more of aggregate unit sales of such Product and such Biosimilars in such country in a calendar quarter, as determined by reference to applicable sales data obtained from a reputable
independent source (e.g., IMS Health), then for the remainder of the Royalty Term for such Product in such country, the royalties that would otherwise be payable by Arsanis under Section 4.3(a) (Royalty Payments) (as adjusted pursuant to
Section 4.3(b) (Adjustment for Third Party IP), to the extent applicable), with respect to Net Sales of such Product in such country shall be reduced by [**] percent ([**]%). 

(d) Compulsory Licensing. If a Compulsory License is granted to a Third Party with respect to a Product in a country, and the royalty
rate payable by such Third Party to Arsanis or its Affiliate or Licensee for such Compulsory License does not equal or exceed the royalty rate provided by Section 4.3(a) (Royalty Payments) (as adjusted pursuant to Section 4.3(b)
(Adjustment for Third Party IP) and 4.3(c) (Biosimilar Competition), to the extent applicable), then in lieu of Royalty Payments with respect to such Third Party’s Net Sales of such Product in such country, Arsanis shall pay to Adimab
[**] percent ([**]%) of the royalties paid by such Third Party to Arsanis or its Affiliate or Licensee with respect to such Third Party’s sales of such Product in such country for the period during which such Compulsory License is in effect,
but only with respect to sales or other dispositions of that Product in that country by that Third Party compulsory licensee. 
 (e)
Royalty Floor. Except as expressly set forth in Section 4.3(d) (Compulsory Licensing), in no event shall the effective royalty rate applicable to Net Sales of a Product in a country (excluding NGO Sales) for purposes of Royalty Payments
hereunder be reduced, by reason of any and all applicable adjustments in the aggregate, to less than [**] percent ([**]%) of Net Sales of such Product in such country. 

(f) No Royalty on NGO Sales. For clarity, no Royalty Payments, royalties or other payments of any kind shall be payable to Adimab with
respect to NGO Sales. 
 (g) [**]. 

  
 - 21 - 

 4.4 Quarterly Payment Timing. All Royalty Payments due under Section 4.3
(Royalties) shall be paid quarterly within [**] days after the end of the relevant calendar quarter for which royalties are due. 

4.5 Royalty Payment Reports. With respect to each calendar quarter, within [**] days after the end of the calendar quarter, Arsanis
shall provide to Adimab a written report stating the number and description of all Products sold during the relevant calendar quarter; the gross sales associated with such sales; and the calculation of Net Sales on such sales, including the amount
of any deduction provided for in the definition of Net Sales. The report shall provide all such information on a country-by-country and Product-by-Product basis. 

4.6 Payment Method. All payments due under this Agreement to Adimab shall be made by bank wire transfer in immediately available funds
to an account designated by Adimab. All payments hereunder shall be made in the legal currency of the United States of America, and all references to “$” or “dollars” shall refer to United States dollars
(i.e., the legal currency of the United States). 
 4.7 Taxes. Adimab will pay any and all taxes levied
on account of any payments made to it under this Agreement. The parties shall reasonably cooperate in good faith to achieve legally-available tax efficiencies related to payments under this Agreement. To the extent that Arsanis is required to deduct
and withhold taxes on any payment to Adimab, Arsanis shall deduct and withhold such taxes and pay the amounts of such taxes to the proper government authority in a timely manner and promptly submit to Adimab an official tax certificate or other
evidence of such withholding sufficient to enable Adimab to claim such payment of taxes. Arsanis shall provide Adimab with reasonable assistance in order to allow Adimab to recover, as permitted by applicable law, withholding taxes, value added
taxes or similar obligations resulting from payments made hereunder or to obtain the benefit of any present or future treaty against double taxation which may apply to such payments. Adimab shall provide Arsanis with any tax forms that may be
reasonably necessary in order for Arsanis not to withhold tax or to withhold tax at a reduced rate under an applicable bilateral tax income treaty. Adimab shall use reasonable efforts to provide any such tax forms to Arsanis at least [**] days prior
to the due date identified by Arsanis for any payment for which Adimab desires that Arsanis apply a reduced withholding rate. Arsanis shall make all payments due hereunder from the United States. 

4.8 Records; Audit. Arsanis shall keep (and shall cause its Affiliates and Licensees to keep) complete and accurate records pertaining
to the sale or other disposition of Products in sufficient detail to permit Adimab to confirm the accuracy of all royalty payments due hereunder for at least [**] full calendar years following the end of the calendar year to which they pertain.
Adimab shall have the right, [**], to cause an independent, certified public accountant of international standing and reasonably acceptable to Arsanis to audit such records solely to confirm Net Sales and royalties for a period covering not more
than the preceding [**] full calendar years. No calendar year shall be subject to audit under this section more than [**]. Such audits may be exercised during normal business hours upon at least [**] days’ prior written notice to Arsanis in the
location where the records are maintained. The auditor will execute a reasonable written confidentiality agreement with Arsanis and will disclose to Adimab only such information as is reasonably necessary to provide Adimab with information regarding
any actual or potential discrepancies between amounts reported and actually paid and amounts payable  

  
 - 22 - 

 
under this Agreement. The auditor will send a copy of the report to Arsanis at the same time it is sent to Adimab. The report sent to both Parties will include the methodology and
calculations used to determine the results. If the audit reveals an underpayment, Arsanis shall promptly pay to Adimab the amount of such underpayment plus interest in accordance with Section 4.11 (Late Payments). If the audit
reveals that the monies owed by Arsanis to Adimab have been understated by more than [**] percent ([**]%) for the period audited, Arsanis shall, in addition, pay the costs of such audit. If such audit discloses an overpayment by Arsanis, then
Arsanis shall have the right to deduct the amount of such overpayment from any amount owed to Adimab under this Agreement. 
 4.9
Foreign Exchange. If any currency conversion shall be required in connection with the calculation of amounts payable hereunder, such conversion shall be made using the rate of exchange for such currency used throughout Arsanis’ accounting
system for financial reporting purposes for the calendar quarter for which payment is due. With any payment in relation to which a currency conversion is performed to calculate the amount of payment due, Arsanis shall provide to Adimab a copy of the
exchange rates used in such calculation. 
 4.10 Non-refundable, non-creditable payments. Each payment that is required under
this Agreement is non-refundable and non-creditable except to the extent set forth in Section 4.3(b) (Adjustment for Third Party IP). 

4.11 Late Payments. Any amount owed by Arsanis to Adimab under this Agreement that is not paid within the applicable time period set
forth herein will accrue interest at the rate of [**] percent ([**]%) above the then-applicable short-term three-month London Interbank Offered Rate (LIBOR) as quoted in the Wall Street Journal (or if it no longer exists, a similarly authoritative
source) calculated on a daily basis, or, if lower, the highest rate permitted under applicable law. 
 ARTICLE 5 

INTELLECTUAL PROPERTY. 

5.1 Ownership and Inventorship. 

(a) Adimab Platform Patents. Adimab shall at all times remain the sole and exclusive owner of the Adimab Platform Patents. 

(b) RSV Antibody Patents. Prior to Option exercise, Adimab shall be the sole and exclusive owner of all RSV Antibody Patents.
From and after Arsanis’ exercise of the Option in accordance with Section 2.2(b) (Option), Arsanis shall be the sole and exclusive owner of all RSV Antibody Patents. 

(c) Other Patents. Except as expressly set forth in Section 2.9 (Effect of Expiration of Option Without Exercise), Section
5.1(b) (RSV Antibody Patents) and Section 9.5(b)(i)(2)(B) (Assignment of RSV Antibody Patents), nothing in this Agreement shall alter the ownership of the Parties’ Patents. 

  
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 (d) Inventorship. For purposes of this Agreement, inventorship of any invention, whether
or not patentable, shall be determined in accordance with United States patent law. 
 5.2 Assignment. Each Party shall promptly
execute and deliver, or require its employees or contractors to execute and deliver, all documents and instruments necessary or reasonably requested by the other Party to effectuate, evidence, record and perfect the Assignment and the ownership of
RSV Antibody Patents set forth in Section 5.1(b) (RSV Antibody Patents) and Section 9.5(b)(i)(2)(B) (Assignment of RSV Patent Rights), and to enable the other Party to apply for and prosecute
such RSV Antibody Patents in any country. In addition, [**]. Each Party hereby designates and appoints the other Party and its duly authorized officers and agents as its agent and attorney-in-fact to act for and on behalf of such Party solely to
execute, deliver and file the foregoing documents and instruments, with the same legal force and effect as if executed by such Party if a Party is unable for any reason to secure the other Party’s or its representatives’ signature on any
such document or instrument. Each Party acknowledges that this appointment is coupled with an interest. Each Party shall make its relevant personnel (and their assignments and signatures on such documents and instruments) reasonably available to the
other Party for assistance in accordance with this Article 5 (Intellectual Property) at no charge. 
 5.3
Patent Prosecution and Maintenance. 
 (a) Adimab Platform Technology. Adimab shall have the sole right (but not the obligation)
to file, prosecute, maintain, defend and enforce all Patents directed to Adimab Platform Technology and all Adimab Platform Patents, all at its own expense. 

(b) RSV Antibody Patents, Evaluation Term Patents and Arsanis Patents. 

(i) Prior to Option Exercise. During the Evaluation Term prior to Option exercise: 

(1) Adimab shall file additional RSV Antibody Patents and prosecute, maintain, defend and enforce all RSV Antibody Patents, in
accordance with instructions from Arsanis and at Arsanis’ expense; 
 (2) Arsanis and its Affiliates shall not file, and shall
not cause to be filed, any additional RSV Antibody Patents, including patent applications that Cover any Adimab RSV Antibody; 
 (3)
Adimab shall provide Arsanis with drafts of proposed patent office submissions with respect to Adimab RSV Antibodies and RSV Antibody Patents, including draft patent applications and related correspondence, no less than [**] business days in advance
of filing; 
 (4) Adimab shall consider in good faith the requests and comments of Arsanis with respect to such drafts; 

  
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 (5) Adimab shall keep Arsanis reasonably informed of progress with regard to the
prosecution and maintenance of RSV Antibody Patents and shall provide Arsanis with copies of all correspondence received from patent offices relating thereto (including office actions and the like) promptly after receipt; and 

(6) Arsanis may, in its sole discretion and at its sole expense, file or cause to be filed applications for Evaluation Term Patents,
[**]. 
 (ii) During the Post-Exercise Term. During the Post-Exercise Term: 

(1) Arsanis shall have the sole right to prosecute, maintain, enforce and defend all RSV Antibody Patents, Evaluation Term Patents, and
Arsanis Patents, all at its own expense; 
 (2) Adimab and its Affiliates shall not file, and shall not cause to be filed, any
additional RSV Antibody Patents; 
 (3) Adimab shall have the right to review and comment on prosecution of RSV Antibody Patents,
and Arsanis shall consider in good faith the requests and comments of Adimab with respect thereto; 
 (4) Arsanis shall provide
Adimab with drafts of proposed patent office submissions with respect to RSV Antibody Patents, including draft patent applications and related correspondence, no less than [**] business days in advance of filing; and 

(5) Arsanis shall keep Adimab reasonably informed of progress with regard to the prosecution and maintenance of RSV Antibody Patents
and shall provide Adimab with copies of all correspondence received from patent offices relating thereto (including office actions and the like) promptly after receipt. 

(c) Responsibility. It is understood and agreed that searching for, identification and evaluation of Third-Party Patents that
may Cover Excluded Technology, including the Sequence of, or any method of using or making, any Licensed Antibody, is the responsibility of Arsanis, and that Adimab shall have no responsibility for the foregoing nor liability if any such Third Party
Patents exist. 
 5.4 Cooperation of the Parties. At the reasonable request of the responsible (as provided for in this Article 5
(Intellectual Property)) Party, the other Party agrees to cooperate fully in the preparation, filing, prosecution, enforcement and maintenance of any RSV Patents under this Agreement. Such cooperation includes executing all
papers and instruments (or causing its personnel to do so) reasonably useful to enable the other Party to apply for and to prosecute patent applications in any country; and promptly informing the other Party of any matters coming to such
Party’s attention that may affect the preparation, filing, prosecution, enforcement or maintenance of any such Patents. Notwithstanding the foregoing, Adimab shall not be required pursuant hereto to disclose Adimab Platform Technology to
Arsanis or to participate in any action against another Adimab customer. 

  
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 ARTICLE 6 

CONFIDENTIALITY; PUBLICITY. 

6.1 General Confidentiality Obligations. 

(a) Confidential Information. Any and all confidential or proprietary information disclosed to one Party by the other Party under this
Agreement is the “Confidential Information” of the disclosing Party; provided, however, that, notwithstanding the foregoing: 

(i) information embodied in Adimab Materials is Adimab’s Confidential Information; 

(ii) information embodied in the Arsanis Materials is Arsanis’ Confidential Information; 

(iii) prior to exercise of the Option, Sequence information (whether as to amino acid sequence or nucleic acid sequence) with respect
to RSV Antibodies shall be deemed the Confidential Information of both Parties; and 
 (iv) from and after the date of Option
exercise: (A) the Sequence information as to the CDRs of RSV Antibodies shall be Confidential Information of Arsanis; and (B) the Sequence information as to the non-CDR portions (i.e., the framework) of RSV Antibodies may be
disclosed by either Party; provided, however, that this clause (B) shall not be construed to require Arsanis to disclose to Adimab any Sequence information with respect to any Arsanis Derived Antibody. 

(b) Limits on Use and Disclosure of Confidential Information. Each Party shall receive and maintain the other Party’s Confidential
Information in strict confidence. Neither Party shall disclose any Confidential Information of the other Party to any Third Party. Neither Party shall use the Confidential Information of the other Party for any purpose other than as required to
perform its obligations or exercise its rights hereunder. Each Party may disclose the other Party’s Confidential Information to the receiving Party’s employees and contractors requiring access thereto for the purposes of this Agreement,
provided, however, that prior to making any such disclosures, each such person shall be bound by written agreement to maintain Confidential Information in confidence and not to use such information for any purpose other than in accordance
with the terms and conditions of this Agreement. Each Party agrees to take all steps necessary to ensure that the other Party’s Confidential Information shall be maintained in confidence including such steps as it takes to prevent the
disclosure of its own proprietary and confidential information of like character. Each Party agrees that this Agreement shall be binding upon its employees and contractors involved in the activities contemplated hereby and that it shall be liable
for any breach by its employees or contractors. The foregoing obligations of confidentiality and non-use shall survive, and remain in effect for a period of [**] years from, the termination or expiration of this Agreement in accordance with Article
9 (Term; Termination). 
 6.2 Exclusions from Nondisclosure Obligation. Information shall not be considered Confidential
Information of a Party (the “Disclosing Party”) and the nondisclosure and nonuse obligations in Section 6.1 (General Confidentiality Obligations) shall not apply to the extent that the other Party (the
“Receiving Party”) can establish by competent written proof that such  

  
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information: (a) was publicly known at the time of disclosure (or generation, as applicable); (b) after disclosure (or generation, as applicable), becomes publicly known by publication
or otherwise, except by breach of this Agreement by the Receiving Party; (c) was in the Receiving Party’s possession at the time of disclosure hereunder; (d) is received by the Receiving Party from a Third Party who has the lawful
right to disclose the Confidential Information and who shall not have obtained the Confidential Information either directly or indirectly from the Disclosing Party; or (e) is independently developed by the Receiving Party (i.e., without
reference to Confidential Information of the disclosing Party); provided, however, that Adimab shall not be permitted to avail itself of: (i) the exceptions set forth in the foregoing clauses (c) and (e) during the Evaluation
Term with respect to Sequence information as to Adimab RSV Antibodies; (ii) the exception set forth in the foregoing clause (c) during the Post-Exercise Term with respect to Sequence information with respect to the CDRs of Adimab RSV
Antibodies; or (iii) the exception set forth in the foregoing clause (e) during the Post-Exercise Term with respect to Sequence information with respect to the CDRs of Adimab RSV Antibodies except to the extent that such Sequences are
independently rediscovered by Adimab without use of any Confidential Information of Arsanis or any Arsanis Materials. 
 6.3 Authorized
Disclosures. If either Party is required, pursuant to a governmental law, regulation or order, to disclose any Confidential Information of the other Party, the receiving Party (a) shall give advance written notice to the disclosing Party,
(b) shall make a reasonable effort to assist the other Party to obtain a protective order requiring that the Confidential Information so disclosed be used only for the purposes for which the law, regulation or order required and (c) shall
disclose the Confidential Information solely to the extent required by the law, regulation or order. In addition, and notwithstanding the provisions of Section 6.1 (General Confidentiality Obligations), the Receiving Party may disclose
Confidential Information of the Disclosing Party as expressly permitted by this Agreement, or if and to the extent such disclosure is reasonably necessary in the following instances: (i) filing or prosecuting Patent Rights as permitted by this
Agreement; (ii) enforcing such party’s rights under this Agreement and in performing its obligations under this Agreement; (iii) prosecuting or defending litigation as permitted by this Agreement; and (iv) in the case of Arsanis
as the Receiving Party, (A) disclosure in submissions to or filings with any Regulatory Authority (including, without limitation, in INDs and NDAs) with respect to any Product, and in correspondence with any Regulatory Authority regarding any
Product or any of the foregoing submissions or filings, and (B) disclosures to the Foundation required by the Grant Documents; provided, however, that in no event may Arsanis disclose Adimab Platform Technology without the prior written
consent of Adimab, which consent may be withheld in Adimab’s sole discretion. 
 6.4 Terms of Agreement. The terms of this
Agreement are the Confidential Information of both Parties. However, each Party shall be entitled to disclose the terms of this Agreement under legally binding obligations of confidence and limited use to: legal, financial and investment banking
advisors; and potential and actual investors and acquirers, and, in the case of Arsanis, potential and actual Licensees, doing diligence and counsel for the foregoing. In addition, if legally required, a copy of this Agreement may be filed by either
Party with the SEC (or relevant ex-U.S. counterpart). In that case, the filing Party will if requested by the other Party diligently seek confidential treatment for terms of this Agreement for which confidential treatment is reasonably available,
and shall provide the non-filing Party reasonable advance notice of the terms proposed for redactions and a reasonable opportunity to request that the filing Party make additional redactions to the extent confidential treatment is reasonably
available under the law. The filing Party shall seek and diligently pursue such confidential treatment requested by the non-filing Party. 

  
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 6.5 Return of Confidential Information. Promptly after the termination or expiration of
this Agreement for any reason (but specifically excluding expiration of the Term in accordance with clause (b) of Section 9.1 (Term)), each Party shall return to the other Party all tangible manifestations of such other Party’s
Confidential Information at that time in the possession of the receiving Party; provided, however, that: (a) a Party may retain one (1) copy of the Confidential Information of the other Party in its files for the sole purpose of
ascertaining and complying with its confidentiality obligations hereunder; (b) a Party shall not be required to destroy any computer files stored securely by such Party only on centralized storage servers (and not on personal computers or
devices) that are created during automatic system back up, so long as such computer files are not readily accessible by such Party’s personnel (other than its information technology specialists who are responsible for maintaining such
Party’s electronic backup services; and (c) the obligation of the receiving Party to return Confidential Information pursuant to this Section 6.5 (Return of Confidential Information)
shall not apply to Confidential Information of the other Party or copies thereof which must be retained pursuant to mandatory applicable law. Any Confidential Information retained will continue to be
subject to the terms of this Agreement. 
 6.6 Publicity. 

(a) Press Releases. The Parties shall issue joint press release announcing the execution of this Agreement in substantially the form
attached hereto as Exhibit C. It is further acknowledged that each Party may desire or be required to issue subsequent press releases relating to this Agreement or activities hereunder, all of which shall be made in accordance with the terms
of this Section 6.6(a) (Press Releases). 
 (i) Disclosure of Significant Achievements. During the Post-Exercise Term:
(A) Adimab may, without the prior review or approval of Arsanis, issue public statements or press releases announcing the exercise of the Option and the achievement of any Milestone Event for which a Milestone Payment is payable hereunder;
provided, however, that no such statement or release shall disclose any Sequence information as to the CDR of the Licensed Antibody contained in the Product that achieved such Milestone Event or otherwise specifically identify such Licensed
Antibody or Product (except that Adimab may identify such Licensed Antibody or Product by the Arsanis product designation used by Arsanis in its public disclosures); and (B) Arsanis may, without the prior review or approval of Adimab, issue
public statements or press releases regarding Products being developed or commercialized by or on behalf of Arsanis, its Affiliates or Licensees, including, without limitation, announcements regarding initiation or completion of clinical trials,
clinical trial results, regulatory filings and approvals, entry into License Agreements, and receipt of payments under License Agreements, and where not unreasonably cumbersome, Arsanis shall include in such statement a recognition of Adimab as the
source of the Adimab RSV Antibodies. 

  
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 (ii) Other Disclosures. Except as expressly set forth in Section 6.6(a)(i) (Disclosure
of Significant Achievements), the Parties agree to consult with each other reasonably and in good faith with respect to the text and timing of subsequent press releases prior to the issuance thereof; provided, however, that a Party may not
withhold consent to such releases that the other Party may determine, based on advice of counsel, are reasonably necessary to comply with applicable laws, including disclosure requirements of the U.S. Securities and Exchange Commission, or with the
requirements of any stock exchange on which securities issued by a Party or its Affiliates are traded. In the event of a required public announcement, to the extent practicable under the circumstances, the Party making such announcement shall
provide the other Party with a copy of the proposed text of such announcement sufficiently in advance of the scheduled release to afford such other Party a reasonable opportunity to review and comment upon the proposed text. Each Party may make
public statements regarding this Agreement in response to questions by the press, analysts, investors or those attending industry conferences or financial analyst calls, or issue press releases, so long as the contents of any such public statement
or press release are contained in a prior public disclosure or public statement approved by the other Party pursuant to this Section 6.6(a)(ii) (Other Disclosures) or permitted by Section 6.6(a)(i) (Disclosure of Significant
Achievements) or Section 6.3 (Authorized Disclosures) and does not reveal Confidential Information of the other Party. 
 (b)
Bundled Press Releases. It is understood and agreed that a Party may sometimes issue press releases that group multiple achievements of such Party. It is understood and agreed that a Party may choose to group text from a previously-approved
press release with other accomplishments or events not relating to this Agreement and, in such event, the only portions of the press release to which Section 6.6(a) (Press Releases) shall apply shall be those portions that relate to this
Agreement or the other Party. 
 6.7 Certain Data. The Parties recognize the need for Adimab to disclose the general capabilities of
the Adimab Platform Technology. In connection therewith, and provided that Adimab does not disclose the identity of Arsanis, any Adimab RSV Antibody, the target thereof (i.e., RSV) or any Sequence information as to the CDRs of Adimab RSV
Antibodies, Adimab shall have the right to disclose generally Adimab RSV Antibody attributes, including the following: [**]. For clarity, Adimab has already published the article by Gilman et al., entitled “Rapid profiling of RSV antibody
repertoires from the memory B cells of naturally infected adult donors”, Sci Immunol., Vol. 1(6), December 16, 2016 (Epublished December 9, 2016), which article includes the sequences of certain Adimab RSV Antibodies. 

ARTICLE 7 

REPRESENTATIONS AND WARRANTIES. 

7.1 Mutual Representations. Each of Adimab and Arsanis hereby represents and warrants to the other of them that the representing and
warranting Party is duly organized in its jurisdiction of incorporation; that the representing and warranting Party has the full power and authority to enter into this Agreement; that this Agreement is binding upon the representing and warranting
Party; that this Agreement has been duly authorized by all requisite corporate action within the representing and warranting Party; and that the execution, delivery and performance by the representing and warranting Party of this Agreement and its
compliance with the terms and conditions hereof does not and shall not conflict with or result in a breach of any of the terms and conditions of or constitute a default under (a) any agreement or other instrument binding or affecting it or its
property, (b) the provisions of its bylaws or other governing documents or (c) any order, writ, injunction or decree of any governmental authority entered against it or by which any of its property is bound. 

  
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 7.2 Representations of Adimab. Adimab hereby represents and warrants to Arsanis that, as
of the Effective Date: 
 [**]. 

7.3 DISCLAIMER OF WARRANTIES. OTHER THAN THE EXPRESS WARRANTIES SET FORTH IN THIS ARTICLE 7 (REPRESENTATIONS AND WARRANTIES), EACH
PARTY DISCLAIMS ALL WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING, WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, VALIDITY OF PATENTS, NON-INFRINGEMENT OF THE INTELLECTUAL PROPERTY RIGHTS OF THIRD
PARTIES, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICES. 
 7.4 Limitation of Liability. EXCEPT FOR LIABILITY FOR
BREACH OF ARTICLE 6 (CONFIDENTIALITY; PUBLICITY), NEITHER PARTY SHALL BE ENTITLED TO RECOVER FROM THE OTHER PARTY ANY SPECIAL, INCIDENTAL, CONSEQUENTIAL OR PUNITIVE DAMAGES IN CONNECTION WITH THIS AGREEMENT OR ANY LICENSE GRANTED HEREUNDER;
PROVIDED, HOWEVER, THAT THIS SECTION 7.4 (LIMITATION OF LIABILITY) SHALL NOT BE CONSTRUED TO LIMIT EITHER PARTY’S INDEMNIFICATION OBLIGATIONS UNDER ARTICLE 8 (INDEMNIFICATION). 

ARTICLE 8 

INDEMNIFICATION 
 8.1
Indemnification by Adimab. Adimab hereby agrees to indemnify, defend and hold harmless (collectively, “Indemnify”) Arsanis, its Affiliates and its and their directors, officers, agents and employees (collectively,
“Arsanis Indemnitees”) from and against any and all liability, loss, damage or expense (including without limitation reasonable attorneys’ fees) (collectively, “Losses”) they may suffer as the result of any
claim, demand, action or other proceeding by any Third Party (collectively, “Third-Party Claims”) arising out of or relating to (a) the breach by Adimab of any warranty, representation, covenant or agreement made by Adimab in
this Agreement, or (b) the gross negligence or intentional misconduct of any Adimab Indemnitee; except, in each case, to the extent such Losses result from (i) [**]. 

8.2 Indemnification by Arsanis. Arsanis hereby agrees to Indemnify Adimab, its Affiliates and its and their directors, officers, agents
and employees (collectively, “Adimab Indemnitees”) from and against any and all Losses they may suffer as the result of Third-Party Claims arising out of or relating to (a) the breach by Arsanis of any warranty, representation,
covenant or agreement made by Arsanis in this Agreement, (b) the gross negligence or intentional misconduct of any Arsanis Indemnitee, (c) the research, testing, development, manufacture, use, handling, storage, sale, offer for sale,
import or other disposition by or on behalf of Arsanis or any of its Affiliates or Licensees or the Foundation of any Licensed Antibody or Product, or (d) the use by Arsanis or its Affiliates or Licensees or the Foundation of any Excluded
Technology; except, in each case, to the extent such Losses result from (i) [**]. 

  
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 8.3 Indemnification Procedures. The obligation of a Party (the “Indemnifying
Party”) under Section 8.1 (Indemnification By Adimab) or Section 8.2 (Indemnification By Arsanis) (as applicable) to Indemnify the other Party (the “Indemnified Party”) and its associated indemnitees –
i.e., the Adimab Indemnitees or Arsanis Indemnitees, as applicable (the “Indemnitees”) – is conditioned on: (a) the Indemnified Party providing the Indemnifying Party prompt written notice of any Third-Party Claim
giving rise to an indemnification obligation hereunder, (b) the Indemnified Party and its Indemnitees permitting the Indemnifying Party to assume direction and control of the defense of the Third-Party Claim (including the right to settle the
Third-Party Claim solely for monetary consideration) using counsel reasonably satisfactory to the Indemnified Party, (c) the Indemnified Party and its Indemnitees cooperating as requested (at the expense of the Indemnifying Party) in the
defense of the Third-Party Claim, and (d) the Indemnified Party and its Indemnitees not compromising or settling such Third-Party Claim without the Indemnifying Party’s prior written consent. The Indemnifying Party shall not agree to any
settlement of such Third-Party Claim or consent to any judgment in respect thereof that does not include a complete and unconditional release of the Indemnified Party and its Indemnitees from all liability with respect thereto, that imposes any
liability or obligation on the Indemnified Party or its Indemnitees or that acknowledges fault by the Indemnified Party or any Indemnitee, without the prior written consent of the Indemnified Party or such Indemnitee, as applicable. If the Parties
cannot agree as to the application of the foregoing Sections 8.1 (Indemnification by Adimab) and 8.2 (Indemnification by Arsanis), each may conduct separate defenses of the Third-Party Claim, and each Party reserves the right to claim
indemnity from the other in accordance with this Article 8 (Indemnification) upon the resolution of the underlying Third-Party Claim. 

ARTICLE 9 
 TERM;
TERMINATION. 
 9.1 Term. The term (the “Term”) of this Agreement shall commence on the Effective Date and,
unless this Agreement is earlier terminated as set forth below in this Article 9 (Term; Termination), shall expire upon (a) the expiration of the Evaluation Term in the event that the Option is not exercised prior to expiration of the
Evaluation Term; or (b) in the event that the Option is exercised, on the expiration of the last-to-expire Royalty Term for any and all Products. Upon expiration of the Term pursuant to clause (b) of this Section 9.1 (Term), the
License shall become royalty-free, fully-paid, irrevocable and perpetual. 
 9.2 Termination for Material Breach. 

(a) Material Breach Other Than Breach of Diligence Obligation. Subject to Section 9.2(c) (Dispute Regarding Breach), and except
in the case of a material breach covered by Section 9.2(b) (Material Breach of Diligence Obligations), each Party shall have the right, in the event of material breach of this Agreement by the other Party, to terminate this Agreement upon
written notice to the other Party if such other Party is in material breach of this 

  
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Agreement and has not cured such breach within [**] days (or [**] days with respect to any payment breach) after notice from the terminating Party requesting cure of the breach. Any such
termination shall become effective at the end of such [**] day period (or [**] day period with respect to any payment breach) unless the breaching Party has cured such breach prior to the end of such period. Notwithstanding the foregoing or Section
9.5 (Effect of Expiration or Termination) to the contrary, but without limiting Adimab’s rights under Section 9.2(b) (Material Breach of Diligence Obligations), after initiation of the first clinical trial of a Product, Adimab may
not terminate this Agreement pursuant to this Section 9.2(a) (Material Breach Other Than Breach of Diligence Obligations), except in the case of uncured material payment breach by Arsanis, but for clarity, Adimab may pursue any and all remedies that
may be available to it at law or in equity as a result of such breach by Arsanis. 
 (b) Material Breach of Diligence Obligation. If
Adimab in good faith believes that Arsanis has failed to comply with its obligations under Section 3.5 (Diligence), Adimab shall so notify Arsanis and, within [**] days thereafter, Arsanis and Adimab will meet and discuss the matter in good
faith and attempt to reach mutual agreement as to whether or not Arsanis is in material breach of Section 3.5 (Diligence) and, if so, to agree upon a mutually acceptable plan for Arsanis to regain compliance with Section 3.5
(Diligence) within a reasonable period. Following such meeting, if either (i) the Parties do not reach mutual agreement within such [**] day period, or (ii) the Parties mutually agree on a plan for Arsanis to regain compliance with
Section 3.5 (Diligence) but Arsanis fails to regain such compliance within the agreed period, then subject to Section 9.2(c) (Dispute Regarding Breach) below, Adimab will have the right, at its sole discretion, to terminate this
Agreement. 
 (c) Dispute Regarding Breach. Any right to terminate this Agreement under this Section 9.2 (Termination For Material
Breach) shall be stayed and the cure period tolled in the event that, during any cure period, the Party alleged to have been in material breach shall have initiated dispute resolution in accordance with Section 10.4 (Dispute) with respect
to the alleged breach, which stay and tolling shall continue until such dispute has been resolved in accordance with Section 10.4 (Dispute). 

9.3 Termination for Convenience. Arsanis may terminate this Agreement for any reason or for no reason upon sixty (60) days’
written notice to Adimab. 
 9.4 Commitments Regarding RSV Antibodies. The Parties agree that if Arsanis or any of its Licensees
develops or commercializes any RSV Antibody or Product, then Arsanis shall pay to Adimab the fees set forth in Article 4 (Financial Terms), including the Option Fee (if not previously paid), Milestone Payments and Royalty Payments, as
applicable, on all RSV Antibodies developed or commercialized by Arsanis or any of its Licensees as (or as if) a Product under this Agreement. Arsanis shall include in each Licensee Agreement an obligation on the part of the applicable Licensee, in
the event that Arsanis is unwilling or unable to pay to Adimab any Milestone Payments and Royalty Payments that become due hereunder with respect to RSV Antibodies developed or commercialized by such Licensee (because, for example, of the
dissolution of Arsanis for bankruptcy or other reasons), to make such payments directly to Adimab; provided, however, that: (a) if such Licensee achieves a Milestone Event for which a Milestone Payment is payable by Arsanis hereunder and
pays to Arsanis a milestone payment with respect to such Milestone Event, but Arsanis fails to remit to Adimab the corresponding 

  
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Milestone Payment, then such Licensee shall have no liability to Adimab for such Milestone Payment; and (b) if such Licensee pays royalties to Arsanis on particular Net Sales of Products by
such Licensee, but Arsanis fails to remit to Adimab the corresponding Royalty Payment with respect to those Net Sales, then such Licensee shall have no liability to Adimab for such Royalty Payment. 

9.5 Effect of Expiration or Termination. 

(a) Any Termination. Upon any termination of this Agreement prior to its expiration, all licenses and rights granted by either Party to
the other Party pursuant to this Agreement (including the Research License, the Option and the License) shall automatically terminate and revert to the granting Party, and all other rights and obligations of the Parties under this Agreement shall
terminate; in each case, except as expressly provided below in this Section 9.5 (Effect of Expiration or Termination) or elsewhere in this Article 9 (Term; Termination). 

(b) Expiration Without Option Exercise, or Termination by Adimab For Material Breach or by Arsanis For Convenience. Solely in the event
of expiration of this Agreement pursuant to clause (a) of Section 9.1 (Term), or termination of this Agreement by Adimab pursuant to Section 9.2 (Termination for Material Breach), or by Arsanis pursuant to Section 9.3
(Termination for Convenience), the following provisions shall apply, subject, in all cases, to Section 9.5(c) (Survival of Licensee Agreements) and Section 9.5(d) (Foundation Rights): 

(i) Termination of Licenses. As applicable: 

(1) Prior to Option Exercise. In the case of expiration of this Agreement pursuant to clause (a) of Section 9.1 (Term), or
termination of this Agreement during the Evaluation Term either by Adimab pursuant to Section 9.2 (Termination for Material Breach) or by Arsanis pursuant to Section 9.3 (Termination for Convenience), the Research License and the Option shall
terminate and be of no further force or effect. 
 (2) After Option Exercise. In the case of or termination of this Agreement during
the Post-Exercise Term either by Adimab pursuant to Section 9.2 (Termination for Material Breach) or by Arsanis pursuant to Section 9.3 (Termination for Convenience): 

(A) Termination But For Fully-Paid Products. The License shall terminate and be of no further force or effect; provided,
however, that if the License with respect to a particular Product in a particular country had become royalty-free, fully-paid, irrevocable and perpetual by virtue of the expiration of the Royalty Term for such Product in such country prior to
such termination (such Product in such country, a “Fully-Paid Product”), then the License with respect to such Fully-Paid Product shall survive such termination; and 

(B) Assignment of RSV Antibody Patents. Effective as of such termination, Arsanis shall, and it hereby does, assign to Adimab all
right, title and interest in and to all RSV Antibody Patents; 

  
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 (ii) Adimab Materials and RSV Antibodies. Within [**] days after such termination,
Arsanis shall (1) either return to Adimab or destroy (at Adimab’s direction and expense) all Adimab Materials and all Adimab RSV Antibodies remaining in the possession of Arsanis (other than Fully-Paid Products), and (2) except as
otherwise mutually agreed by the Parties in writing, destroy all quantities of Arsanis Derived Antibodies in the possession of Arsanis (other than Fully-Paid Products); 

(iii) Non-Exclusive Unblocking License to Adimab. Effective as of such termination, Arsanis shall, and it hereby does, grant to
Adimab, a non-exclusive, worldwide, royalty-free, fully-paid license, with the right to sublicense through multiple tiers, under Blocking Arsanis Patents solely to make, have made, use, sell, have sold, offer for sale and import Adimab RSV
Antibodies and products comprising or containing Adimab RSV Antibodies (but excluding Fully-Paid Products, if any) in the Field. For clarity, the sole purpose of the license that may be granted pursuant to this Section 9.5(b)(iii) (Non-Exclusive
Unblocking License to Adimab) is to provide Adimab with freedom to operate under Blocking Arsanis Patents solely with respect to the manufacture, use, sale, offer for sale and import of Adimab RSV Antibodies and products comprising or containing
Adimab RSV Antibodies (excluding Fully-Paid Products) in the Field, and this Section 9.5(b)(iii) (Non-Exclusive Unblocking License to Adimab) does not, and shall not be construed to, obligate Arsanis to disclose any Blocking Arsanis Patent or
the Arsanis Invention(s) claimed therein to Adimab; 
 (iv) Right of Negotiation for Exclusive License and Product Transfer to
Adimab. Effective as of such termination, Arsanis shall, and it hereby does, grant to Adimab, a right of first negotiation, exercisable within [**] days after termination, to obtain, upon commercially reasonable terms and conditions to be
negotiated in good faith by the Parties: 
 (1) Exclusive License. An exclusive, worldwide, royalty-bearing license, with the right
to sublicense through multiple tiers, under the Blocking Arsanis Patents, Other Arsanis Patents and Arsanis Know-How, in each case, solely to develop, make, have made, use, sell, have sold, offer for sale and import RSV Antibodies and Products
(excluding Fully-Paid Products) in the Field; provided, however, that, to the extent that Blocking Arsanis Patents, Other Arsanis Patents or Arsanis Know-How includes Patents or Know-How licensed to Arsanis by a Third Party that is subject to
royalty or milestone payment obligations to such Third Party with respect to any RSV Antibody or Product, then Arsanis shall so notify Adimab, together with a true, complete and correct description of such royalty and milestone payment obligations,
and the inclusion of such Patents or Know-How in the Blocking Arsanis Patents, Other Arsanis Patents or Arsanis Know-How (as applicable) shall be subject to Adimab’s agreeing in writing to pay, and promptly paying, all royalty and milestone
payments that become due to such Third Party by reason of the development, manufacture, use, sale, offer for sale or import of RSV Antibodies and Products by or on behalf of Adimab or its Affiliates, licensees or sublicensees (in addition to the
mutually agreed compensation payable to Arsanis for the grant of rights described in this Section 9.5(b)(iv) (Exclusive Unblocking License and Regulatory Transfer to Adimab)); 

(2) Regulatory Filings and Approvals. The transfer and assignment to Adimab of all Arsanis Regulatory Filings, including INDs and
NDAs, and all Arsanis Approvals, including Marketing Approvals, in each case for RSV Antibodies and Products (other than Fully-Paid Products) in the Field controlled by Arsanis or any of its Affiliates; and 

  
 - 34 - 

 (3) Other Transfers. The transfer and assignment or sublicense of such other elements as
may be necessary or useful for Adimab to continue the development and commercialization of RSV Antibodies and Products as conducted by Arsanis prior to such termination, including, for example, transferring (to the extent requested by Adimab) formal
relationships with manufacturing organizations, patient groups and payors that, in each case, are specific to RSV Antibodies and Products, as well as other Product-specific items such as pharmacovigilance databases, and data related to indication,
use, risks, and benefits. 
 (v) Prohibition on Further Use. Arsanis and its Affiliates shall not, and shall not grant any license
or other right to, or otherwise cause or permit, any Third Party to, develop, manufacture or commercialize any RSV Antibody or Product (other than Fully-Paid Products). 

(c) Survival of License Agreements. In the event that (i) Arsanis has entered into a Licensee Agreement consistent with the terms
of this Agreement (including the provisions of Section 3.2 (Licensees and Sublicensees)), (ii) this Agreement is terminated, and (iii) such Licensee Agreement is in effect at the time of such termination, then such Licensee
Agreement will survive such termination of this Agreement; provided, however, that the Licensee assumes all of Arsanis’ obligations hereunder with respect to the Licensed Antibodies and Products covered by such Licensee Agreement
(including those obligations set forth in Section 3.5 (Diligence), Section 3.7 (Disclosure Regarding Arsanis Efforts), and Section 9.4 (Commitments Regarding RSV Antibodies), and pays to Adimab all amounts that would have been
due to Adimab from Arsanis as a result of Licensee’s activities (including those obligations set forth in Article 4 (Financial Terms)). 

(d) Foundation Rights. Notwithstanding any other provision of this Agreement to the contrary, the Parties acknowledge and agree that
any and all Foundation Rights that have accrued or become effective prior to any expiration of this Agreement pursuant to clause (a) of Section 9.1 (Term) or the effective date of any termination of this Agreement prior to its expiration
pursuant to clause (b) of Section 9.1 (Term) shall survive such expiration or termination of this Agreement and remain in full force and effect in accordance with the terms of the Grant Documents. Adimab further acknowledges and agrees
that, to the extent that (i) the RSV Antibody Patents are assigned back to Adimab, (ii) the Evaluation Term Patents (if any) are assigned to Adimab, (iii) Evaluation Term Data and Sequence information for Arsanis Derived Antibodies
created during the Evaluation Term are disclosed to Adimab, and/or (iv) any Blocking Arsanis Patents, Other Arsanis Patents or Arsanis Know-How are licensed to Adimab, the foregoing shall remain subject to the Foundation Rights to the same
extent as they were immediately prior to such expiration or termination, and Adimab shall be bound by the Global Access Commitment with respect thereto. 

  
 - 35 - 

 9.6 Accrued Obligations; Survival. Neither expiration nor any termination of this
Agreement shall relieve either party of any obligation or liability accruing prior to such expiration or termination, nor shall expiration or any termination of this Agreement preclude either party from pursuing all rights and remedies it may have
under this Agreement, at law or in equity, with respect to breach of this Agreement. In addition, the parties’ rights and obligations under Sections 2.9 (Effect of Expiration of Option Without Exercise), 3.4 (Acknowledgment Regarding
Arsanis Derived Antibodies), 3.8 (Acknowledgment of Foundation Rights), 4.4 (Quarterly Payment Timings) through 4.11 (Late Payments) (with respect to payment obligations outstanding or having accrued as the effective date of
termination or expiration), 5.1 (Ownership and Inventorship), 5.2 (Assignment), 6.1 (General Confidentiality Obligations), 6.2 (Exclusions from Nondisclosure Obligation), 6.3 (Authorized Disclosures), 6.4 (Terms
of Agreement), 6.5 (Return of Confidential Information), 6.7 (Certain Data), 7.3 (Disclaimer of Warranties), 7.4 (Limitation of Liability), 9.4 (Commitments Regarding RSV Antibodies), 9.5 (Effect of
Expiration or Termination) and 9.6 (Accrued Obligations; Survival), and Articles 1 (Definitions), 8 (Indemnification) and 10 (Miscellaneous) shall survive any expiration or termination of this Agreement. 

ARTICLE 10 

MISCELLANEOUS. 
 10.1 No
Implied Licenses. No right or license under any Patent, Know-How or other intellectual property of either Party is granted or shall be deemed to have been granted under this Agreement by implication. All such rights or licenses are or shall be
granted only as expressly provided in this Agreement. 
 10.2 Bankruptcy Code. All rights and licenses granted under or pursuant to
this Agreement are, and shall otherwise be deemed to be, for purposes of Section 365(n) of Title 11 of the United States Code and other similar laws in any jurisdiction outside the US (collectively, the “Bankruptcy Laws”),
licenses of rights to be “intellectual property” as defined under the Bankruptcy Laws. If a case is commenced during the Term by or against a Party under Bankruptcy Laws then, unless and until this Agreement is rejected as provided in such
Bankruptcy Laws, such Party (in any capacity, including debtor-in-possession) and its successors and assigns (including a trustee) shall perform all of the obligations provided in this Agreement to be performed by such Party. If a case is commenced
during the Term by or against a Party under the Bankruptcy Laws, this Agreement is rejected as provided in the Bankruptcy Laws and the other Party elects to retain its rights hereunder as provided in the Bankruptcy Laws, then the Party subject to
such case under the Bankruptcy Laws (in any capacity, including debtor-in-possession) and its successors and assigns (including a Title 11 trustee), shall provide to the other Party copies of all Information necessary for such other Party to
prosecute, maintain and enjoy its rights under the terms of this Agreement promptly upon such other Party’s written request therefor. All rights, powers and remedies of the non-bankrupt Party as provided herein are in addition to and not in
substitution for any and all other rights, powers and remedies now or hereafter existing at law or in equity (including the Bankruptcy Laws) in the event of the commencement of a case by or against a Party under the Bankruptcy Laws. 

10.3 Independent Contractors. The Parties shall perform their obligations under this Agreement as independent contractors. Nothing
contained in this Agreement shall be construed to be inconsistent with such relationship or status. This Agreement and the Parties’ relationship in connection with it shall not constitute, create or in any way be interpreted as a joint venture,
fiduciary relationship, partnership, or agency of any kind. 

  
 - 36 - 

 10.4 Dispute Resolution. 

(a) Initial Dispute Resolution. Subject to Section 10.4(c) (Court Actions), either Party may refer any dispute in connection
with this Agreement (“Dispute”) not resolved by discussion of the Alliance Managers to senior executives of the Parties (for Adimab, its CEO or his designee and for Arsanis, its CEO or his designee) for good-faith discussions over a
period of not less than [**] days (the “Senior Executives Discussions”). Each Party will make its executives reasonably available for such discussions. 

(b) Disputes Not Resolved Between the Parties. 

(i) Arbitration. Subject to Section 10.4(c) (Court Actions) below, any Dispute that is not resolved under Section 10.4(a)
(Initial Dispute Resolution) within the period specified above shall be resolved by final and binding arbitration administered by JAMS (the “Administrator”) in accordance with its then-effective Comprehensive Arbitration
Rules and Procedures (the “Rules”), except to the extent any such Rule conflicts with the express provisions of this Section 10.4(b) (Arbitration). (Capitalized terms used but not otherwise defined in this Agreement shall
have the meanings provided in the Rules.) The Arbitration shall be conducted by three (3) neutral arbitrators, each of whom shall be a lawyer with at least fifteen (15) years of experience with a law firm or corporate law department and at
least ten (10) years representing (either as outside counsel or in-house counsel) companies in the pharmaceutical or biotechnology industry in connection with licensing transactions; provided, however, that no such individual shall be a
current or former employee or director, or a current stockholder, of either party or any of their respective Affiliates. Each party shall appoint one arbitrator, and the two so-appointed arbitrators shall jointly nominate the third arbitrator. The
arbitration and all associated discovery proceedings and communications shall be conducted in English, and the arbitration shall be held in New York, New York. 

(ii) Hearing; Decision. The Hearing shall commence within [**] days after the discovery cutoff. The arbitrators shall require that
each party submit concise written statements of position and shall permit the submission of rebuttal statements, subject to reasonable limitations on the length of such statements to be established by the arbitrators. The Hearing shall be no longer
than [**] business days in duration. The arbitrators shall also permit the submission of expert reports. The arbitrators shall render the Award within [**] days after the arbitrators declares the Hearing closed, and the Award shall include a written
statement describing the essential findings and conclusions on which the Award is based, including the calculation of any damages awarded. The arbitrators will, in rendering their decision, apply the substantive law of the State of New York,
excluding its conflicts of laws principles with the exception of sections 5-1401 and 5-1402 of New York General Obligations Law. The arbitrators’ authority to award special, incidental, consequential or punitive damages shall be subject to the
limitation set forth in Section 7.4 (Limitations on Liability). The Award rendered by the arbitrators shall be final, binding and non-appealable, and judgment may be entered upon it in any court of competent jurisdiction. 

  
 - 37 - 

 (iii) Costs. Each Party shall bear its own costs and expenses and attorneys’ fees
and an equal share of the arbitrators’ fees and any administrative fees or arbitration, unless in each case the arbitrators order otherwise, which they are hereby empowered, authorized and instructed to do if they determine that to be fair and
appropriate. 
 (iv) Confidentiality of Process and Awards. Except to the extent necessary to confirm an award or as may be
permitted by Section 6.3 (Authorized Disclosures) or Section 6.6(a) (Press Releases), neither Party shall disclose the existence, content or results of an arbitration under this Agreement without the prior written consent of the other
Party. 
 (v) Statute of Limitations. In no event shall an arbitration be initiated after the date when commencement of a legal or
equitable proceeding based on the subject matter of the Dispute would be barred by the applicable statute of limitations under New York law. 

(c) Court Actions. Nothing contained in this Agreement shall deny either Party the right to seek injunctive or other equitable relief
from a court of competent jurisdiction in the context of a bona fide emergency or prospective irreparable harm, and such an action may be filed and maintained notwithstanding any ongoing discussions between the Parties or any ongoing arbitration
proceeding. In addition, either Party may bring an action in any court of competent jurisdiction to resolve disputes pertaining to the validity, construction, scope, enforceability, infringement or other violations of Patents or other intellectual
property rights, and no such claim shall be subject to arbitration pursuant to Section 10.4(b) (Disputes Not Resolved Between the Parties). 

10.5 Governing Law. This Agreement shall be governed by and interpreted in accordance with the laws of the State of New York, excluding
its conflicts of laws principles with the exception of sections 5-1401 and 5-1402 of New York General Obligations Law. 
 10.6
Entire Agreement. This Agreement (including its Exhibits) set forth all the covenants, promises, agreements, warranties, representations, conditions and understandings between the Parties with respect to the subject matter hereof and supersedes
and terminates all prior agreements and understandings between the Parties with respect to such subject matter. No subsequent alteration, amendment, change or addition to this Agreement shall be binding upon the Parties unless reduced to writing and
signed by the respective authorized officers of the Parties. 
 10.7 Assignment. Except as expressly provided
hereunder, neither this Agreement nor any rights or obligations hereunder may be assigned or otherwise transferred by either Party without the prior written consent of the other Party (which consent shall not be unreasonably withheld); provided,
however, that: 
 (a) either party may assign this Agreement and its rights and obligations hereunder without the other
party’s consent: 

  
 - 38 - 

 (i) in connection with the transfer or sale of all or substantially all of the business
of such party to which this Agreement relates to a Third Party (“Third Party Acquirer”), whether by merger, sale of stock, sale of assets or otherwise (each, a “Sale Transaction”); provided, however, that in
the event of a Sale Transaction (whether this Agreement is actually assigned or is assumed by the Third Party Acquirer or the surviving corporation resulting from such Sale Transaction by operation of law (e.g., in the context of a reverse
triangular merger)), intellectual property rights of the Third Party Acquirer that existed prior to the Sale Transaction shall not be included in the technology licensed or assigned hereunder or otherwise subject to this Agreement; or 

(ii) to an Affiliate; provided, however, that the assigning party shall remain liable and responsible to the non-assigning
party hereto for the performance and observance of all such duties and obligations by such Affiliate; and 
 (b) Adimab may assign or
transfer its rights to receive payments under this Agreement (but none of its obligations or liabilities), without Arsanis’ consent, to an Affiliate or to a Third Party in connection with the sale of, monetization of, transfer of, or obtaining
financing on the basis of the payments due to Adimab under this Agreement or debt or project financing in connection with this Agreement. 

This Agreement shall be binding upon and shall inure to the benefit of the Parties and their respective successors and permitted assigns. Any
assignment of this Agreement not made in accordance with this Agreement is prohibited hereunder and shall be null and void. 
 10.8
Severability. If one or more of the provisions in this Agreement are deemed unenforceable by law, then such provision shall be deemed stricken from this Agreement and the remaining provisions shall continue in full force and effect, and the
Parties shall substitute for the unenforceable provision an enforceable provision that conforms as nearly as possible with the original intent of the Parties. 

10.9 Force Majeure. A Party shall be excused from liability for the failure or delay in performance of such Party’s obligations
under this Agreement to the extent that such performance is prevented by a Force Majeure. Such excuse from liability shall be effective only to the extent and duration of the Force Majeure event(s) causing the failure or delay in performance. The
affected Party shall notify the other Party of such Force Majeure event(s) as soon as reasonably practicable and shall use reasonable efforts to resume performance of its obligations under this Agreement as soon as reasonably practicable.

 10.10 Notices. Any notice required or permitted to be given under this Agreement shall be in writing, shall specifically refer
to this Agreement and shall be deemed to have been sufficiently given for all purposes if mailed by first class certified or registered mail, postage prepaid, delivered by express delivery service or personally delivered. Unless otherwise specified
in writing, the mailing addresses of the Parties shall be as described below. 
 If to Adimab: 

Adimab, LLC 
 7 Lucent Drive 

Lebanon, NH 03766 
 Attention:
General Counsel 

  
 - 39 - 

 with a required copy to: 

Attention: Head, Business Development at the same address. 

In the case of Arsanis: 
 Arsanis
Inc. 
 890 Winter Street 

Suite 230 
 Waltham, MA 02451-1472

 Attention: CEO 
 10.11
Construction. This Agreement has been prepared jointly and shall not be strictly construed against either Party. Ambiguities, if any, in this Agreement shall not be construed against any Party, irrespective of which Party may be deemed to have
authored the ambiguous provision. 
 10.12 Headings. The headings for each Article and Section in this Agreement have been
inserted for convenience of reference only and are not intended to limit or expand on, nor to be used to interpret, the meaning of the language contained in the particular Article or Section. 

10.13 No Waiver. Any delay in enforcing a Party’s rights under this Agreement or any waiver as to a particular default or other
matter shall not constitute a waiver of such Party’s rights to the subsequent enforcement of its rights under this Agreement, excepting only as to an express written and signed waiver as to a particular matter for a particular period of time
executed by an authorized officer of the waiving Party. 
 10.14 Performance by Affiliates. A Party may perform
some or all of its obligations under this Agreement through Affiliate(s) or may exercise some or all of its rights under this Agreement through Affiliates. However, each Party shall remain responsible and be guarantor of the performance by its
Affiliates and shall cause its Affiliates to comply with the provisions of this Agreement in connection with such performance as if such Party were performing such obligations itself, and references to a Party in this Agreement shall be deemed to
also reference such Affiliate. In particular and without limitation, all Affiliates of a Party that receive Confidential Information of the other Party pursuant to this Agreement shall be governed and bound by all obligations set forth in Article 6
(Confidentiality; Publicity), and shall (to avoid doubt) be subject to the intellectual property assignment and other intellectual property provisions of Article 5 (Intellectual Property) as if they were the original Party to this
Agreement (and be deemed included in the actual Party to this Agreement for purposes of all intellectual property-related definitions). 

10.15 Counterparts. This Agreement may be executed in one or more identical counterparts, each of which shall be deemed to be an
original, and which collectively shall be deemed to be one and the same instrument. In addition, signatures may be exchanged by facsimile or PDF. 

[Remainder of Page Left Intentionally Blank; Signature Page Follows] 

  
 - 40 - 

 IN WITNESS WHEREOF, the
Parties have by duly authorized persons executed this Agreement to be effective as of the Effective Date. 
  

							
	ARSANIS INC.:	 	ADIMAB, LLC:
				
	By:	 	/s/ Michael P. Gray	 	By:	 	/s/ Tillman Gerngross
	Title:	 	Chief Financial Officer	 	Title:	 	Tillman Gerngross
	Date:	 	February 24, 2017	 	Date:	 	2/25/2017

  
 - 41 - 

 EXHIBITS LIST 

A –ADIMAB RSV ANTIBODIES 

B –RSV ANTIBODY PATENTS 

C –PRESS RELEASE 

 EXHIBIT A 

Adimab RSV Antibodies 

Confidential Materials omitted and filed separately with the Securities and Exchange Commission. A total of 3 pages were omitted. [**] 

  
 A-1 

 Exhibit B 

RSV Antibody Patents 
 [**] 

 EXHIBIT C 

Press Release 
  

			
	

	  	

 DRAFT- NOT FOR IMMEDIATE RELEASE 

Arsanis and Adimab Enter Into License Agreement to Target Respiratory Syncytial Virus (RSV) With Monoclonal Antibodies 

Arsanis awarded up to $9.3 million from the Bill & Melinda Gates Foundation to advance RSV antibody program towards the clinic

 WALTHAM, MA., US, VIENNA, Austria, and LEBANON, NH., US – [February __, 2017] – Arsanis, Inc., a clinical-stage biopharmaceutical
company developing targeted monoclonal antibodies for pre-emptive and post-infection treatment of serious infectious diseases, and Adimab, LLC, the global leader in the discovery and optimization of fully human monoclonal and bispecific antibodies,
announced today they have entered into an agreement under which Arsanis has secured the exclusive, worldwide license to antibodies targeting respiratory syncytial virus (RSV) that were discovered by Adimab. Arsanis will initially focus on the
selection of a lead RSV antibody candidate and has received a grant of up to $9.3 million from the Bill & Melinda Gates Foundation to advance the selected antibody to IND filing. 

“Arsanis’ partnerships with Adimab and the Gates Foundation will allow us to apply our deep expertise in the discovery and development of
anti-infective antibodies to advance highly potent human monoclonal antibodies for the prevention of RSV infection,” said Rene Russo, Pharm.D., BCPS, President and Chief Executive Officer, Arsanis. “We believe this approach has the
potential to address a significant global need for effective and accessible RSV therapeutics in both developed and developing countries.” 
 Under the
agreement with Adimab, Arsanis has exclusively licensed a panel of RSV antibodies for the purpose of evaluating and selecting the best therapeutic leads under an exclusive global development and commercialization license. Adimab will be entitled to
receive license fees and development milestones, as well as a royalty on net sales. 
 “We are very pleased that Arsanis and the Gates Foundation are
collaborating on this important program. Through our B cell isolation approach, Adimab has identified highly potent antibodies against a number of infectious disease targets. The RSV antibodies licensed to Arsanis include some of the most potent RSV
neutralizers reported to date,” said Guy Van Meter, VP of Business Development at Adimab. “This new agreement expands an already successful relationship with Arsanis, under which Arsanis’ lead program ASN100 for S. aureus
pneumonia, currently in a Phase 2 clinical study, was discovered.” 

 About Respiratory Syncytial Virus (RSV) 

RSV is a highly contagious virus that causes infections in both the upper and lower respiratory tract. RSV infects nearly every child at least once by the age
of two years and is a major cause of hospitalization due to respiratory infection in children, the elderly, and immunocompromised patients. RSV infection typically results in cold-like symptoms but can lead to more serious respiratory illnesses such
as croup, pneumonia, bronchiolitis, and in extreme cases, death. RSV infection in the pediatric and adult populations account for more than 300,000 hospitalizations per year in the U.S. In the developing world, RSV is responsible for 30 million
cases of acute respiratory tract infection and 200,000 deaths per year. As a result, there is a significant need for novel therapeutics to prevent RSV infection. 

About Arsanis, Inc. 
 Arsanis is a clinical-stage
biotechnology company leading the development of targeted monoclonal antibodies (mAbs) for pre-emptive therapy and treatment of serious infectious diseases. The company’s current programs address pathogenic processes selectively, aiming to
preserve the healthy microbiome and potentially allowing Arsanis to address critical infections without contributing to the problem of resistance. The company is building a broad product pipeline addressing the most important infectious diseases
that threaten patients globally. Its lead clinical program, ASN100, is aimed at serious Staphylococcus aureus infections and is being evaluated in a Phase 2 clinical study for the prevention of S. aureus pneumonia in high-risk
patients. 
 Arsanis is a U.S. company headquartered in Waltham, Massachusetts, with European research and preclinical development operations headquartered
in Vienna, Austria (Arsanis Biosciences GmbH). For more information, please visit the Arsanis website at www.arsanis.com. 
 About Adimab 

Adimab has established antibody discovery collaborations with many leading pharmaceutical companies, such as Merck, Novo Nordisk, Biogen, GSK, Roche, Novartis,
Eli Lilly, Genentech, Celgene, Gilead, Kyowa Hakko Kirin, Takeda and Sanofi. In addition, Adimab has partnered with several smaller publicly traded companies, such as Acceleron, Merrimack Pharmaceuticals, Kite, Five Prime, as well as leading
venture-backed companies including Jounce, Mersana, Alector, Surface Oncology, Potenza, Tizona, Tusk and several academic institutions such as Memorial Sloan Kettering and MD Anderson. The Adimab antibody discovery and optimization platform has also
been internalized by several large pharma partners; Adi-inside partners include Merck, Novo Nordisk, Biogen and GSK. 
 Adimab’s integrated
antibody discovery and optimization platform provides unprecedented speed from antigen to purified, full-length human IgGs. Adimab offers fundamental advantages by delivering diverse panels of therapeutically relevant antibodies that meet the most
aggressive standards for affinity, epitope coverage, species cross-reactivity and developability. Adimab enables its partners to rapidly expand their biologics pipelines through a broad spectrum of technology access arrangements. For more
information, please visit the Adimab website at http://www.adimab.com. 

 Arsanis Contacts: 

 

	
	 Media Contact:

	 Ten Bridge Communications

	 Krystle Gibbs

	 krystle@tenbridgecommunications.com, 508-479-6358

  

	
	 Investor Contact:

	 Michael Gray

	 Chief Financial and Chief Business Officer

	 mike.gray@arsanis.com, 781-819-5201

  

	
	 Adimab Contact:

	 Guy Van Meter

	 Vice President, Business Development

	 Guy.vanmeter@adimab.com, 603-653-5775EX-10.20

 Exhibit 10.20 

Confidential Materials omitted and filed separately with the 

Securities and Exchange Commission. Double asterisks denote omissions. 

GRANT AGREEMENT 
 Investment
ID OPP1170296 
 AGREEMENT SUMMARY & SIGNATURE PAGE 

 

			
	GRANTEE INFORMATION
	Name:	  	Arsanis, Inc
	Tax Status:	  	Not exempt from federal income tax under U.S. IRC § 501(c)(3) You confirm that the above information is correct and agree to notify the Foundation immediately of any change.
	Expenditure Responsibility:	  	This Agreement is subject to “expenditure responsibility” requirements under the U.S. Internal Revenue Code.
	Mailing Address:	  	890 Winter Street Suite 230 Waltham, MA 02451-1472 United States
	Primary Contact:	  	[**]

  

			
	FOUNDATION INFORMATION
	Mailing Address:	  	P. O. Box 23350, Seattle, WA 98102, U.S.A.
	Primary Contact:	  	[**]

  

			
	AGREEMENT INFORMATION
	Title:	  	Respiratory Syncytial Virus (RSV) Program Proposal
	“Charitable Purpose”:	  	To fund pre-clinical development of monoclonal antibodies (mAbs) for the prevention of respiratory syncytial virus (RSV) infection in newborns
	“Start Date”:	  	Date of last signature
	“End Date”:	  	August 31, 2019
	This Agreement includes and incorporates by this reference:	  	 This Agreement Summary & Signature Page and:

•    Grant Amount and Reporting & Payment Schedule (Attachment A)

•    Terms and Conditions (Attachment B)

•    List of Developing Countries (Attachment C)

•    Project Information (Submitted January 13, 2017)

•    Project Plan (date submitted February 8, 2017)

•    Budget (date submitted February 3, 2017)

  
 Page 1 of 25 

 THIS AGREEMENT is between Arsanis, Inc (“You” or
“Grantee”) and the Bill & Melinda Gates Foundation (“Foundation”), and is effective as of the date of last signature. Each party to this Agreement may be referred to individualy
as a “Party” and together as the “Parties.” As a condition of this grant, the Parties enter into this Agreement by having their authorized representatives sign below. 

 

									
	BILL & MELINDA GATES FOUNDATION	 		 	ARSANIS, INC
					
		 	/s/ Trevor Mundel	 		 		 	/s/ Mike Gray
	By:	 	Trevor Mundel	 		 	By:	 	Mike Gray
	Title:	 	President of Global Health	 		 	Title:	 	Chief Financial and Chief Business Officer
	Date	 	February 10, 2017	 		 	Date	 	February 20, 2017

  
 Page 2 of 25 

 GRANT AGREEMENT 

Investment ID OPP1170296 

ATTACHMENT A 
 GRANT
AMOUNT AND REPORTING & PAYMENT SCHEDULE 
 GRANT AMOUNT 

The Foundation will pay You up to the total grant amount specified in the Reporting & Payment Schedule below. The Foundation’s Primary Contact
must approve in writing any Budget cost category change of more than [**]%. 
 REPORTING & PAYMENT SCHEDULE 

For the avoidance of doubt, the Foundation will make the first payment in full subject to the applicable milestone and compliance with this Agreement, but the
subsequent payment is an “up to” amount and may be reduced in the Foundation’s discretion based on its assessment of Your completion of, or progress against, targets and milestones. 

REPORTING 
 You will submit reports according to the
Reporting & Payment Schedule using the Foundation’s templates or forms, which the Foundation will make available to You and which may be modified from time to time. For a progress or final report to be considered satisfactory, it must
demonstrate meaningful progress against the targets or milestones for that investment period. If meaningful progress has not been made, the report should explain why not and what adjustments You are making to get back on track. Please notify the
Foundation’s Primary Contact if You need to add or modify any targets or milestones. The Foundation must approve any such changes in writing. You agree to submit other reports the Foundation may reasonably request. 

 

									
	REPORTING & PAYMENT SCHEDULE
	 Investment
Period
	 	 Milestone or Reporting Deliverable
	  	Due By	  	Payment
Date	  	Payment
Amount
(U.S.$)
		 	Countersigned Grant Agreement	  	March 1,
2017	  		  	
		 	Confirmation of execution of Option Agreement enabling access to IP for the Project and consistent with Global Access and this Agreement	  	Within [**]
days after
Countersigned
Grant
Agreement	  	Within [**]
days after
receipt
Confirmation
of Option
Agreement	  	$[**]
	Start date to End Date	 	Quarterly Financial & Progress Updates	  	Quarterly	  		  	

  
 Page 3 of 25 

									
		  	Global Access Strategy satisfactory to the Foundation	  	[**]	  	[**]	  	Up to $[**]
		  	Updated Financial Statements	  	  	  
		  	Product Development Summary and Status Candidate Target Product Profile Revised Budget, including Sub-award Budget	  	  	  
		  	[**]	  		  		  	
	[**]	  	[**]	  	[**]	  		  	
		  	[**]	  	[**]	  	[**]	  	[**]
	[**]	  	[**]	  	[**]	  		  	
		  	[**]	  	[**]	  		  	
	Start Date through End Date	  	Final Report	  	Within [**] days
of End Date	  		  	
	Total Grant Amount	  	Up to $9,330,878

 GO/NO-GO MILESTONE(S) 

You will provide the results of the “go/no-go” milestone(s) identified in the Reporting & Payment Schedule by the applicable due date.
During the course of the project The Foundation will then determine, in its sole discretion, whether to provide continued funding under this Agreement. If the Foundation determines that it will not continue funding, the Foundation will terminate
this Agreement in accordance with its terms. 

  
 Page 4 of 25 

 GRANT AGREEMENT 

Investment ID OPP1170296 

ATTACHMENT B  

TERMS & CONDITIONS 
 This Agreement is
subject to the following terms and conditions. 
 PROJECT SUPPORT 

PROJECT DESCRIPTION AND CHARITABLE PURPOSE 

The Foundation is awarding You this grant to carry out the project described in the Project Plan and Project Information Sheet (collectively,
“Project”) in order to further the Charitable Purpose. 
 MANAGEMENT OF FUNDS 

USE OF FUNDS 
 You may not
use funds provided under this Agreement (“‘Grant Funds”) for any purpose other than the Project. You may not use Grant Funds to reimburse any expenses You incurred prior to the Start Date. 

INVESTMENT OF FUNDS 
 You must invest Grant
Funds in highly liquid investments with the primary objective of preservation of principal (e.g., interest-bearing bank accounts or a registered money market mutual fund) so that the Grant Funds are available for the Project. Together with any
progress or final reports required under this Agreement, You must report the amount of any currency conversion gains (or losses) and the amount of any interest, or other income generated by the Grant Funds (collectively, “Income”).
Any Income must be used for the Project. 
 GLOBAL ACCESS 

GLOBAL ACCESS COMMITMENT 

You will conduct and manage the Project and the Funded Developments in a manner that ensures Global Access. Your Global Access commitments will
survive the term of this Agreement. “Funded Developments” means the products, services, processes, technologies, materials, software, data, other innovations, and intellectual property resulting from the Project (including
modifications, improvements, and further developments to Background Technology). “Background Technology’ means any and all products, services, processes, technologies, materials, software, data, or other innovations, and
intellectual property created by You or a third party prior to or outside of the Project used as part of the Project. “Global Access” means: (a) the knowledge and information gained from the Project will be promptly and broadly
disseminated; and (b) the Funded 

  
 Page 5 of 25 

 
Developments will be made available and accessible at an affordable price (i) to people most in need within developing countries, or (ii) in support of the U.S. educational system and
public libraries, as applicable to the Project. 
 GLOBAL ACCESS MILESTONES 

To further define Your Global Access commitments, You are required to complete a Global Access Strategy and any other Global Access activities
and documentation listed in the Reporting & Payment Schedule. The Global Access Strategy should address the following concepts with respect to all Funded Developments: (a) identification of Background Technology at the outset and
during the Project and specific strategies to ensure access to such Background Technology; (b) agreements and/or procedures for transfers of materials and data among Project Collaborators or third parties relevant to the Project;
(c) reporting processes for the creation of Funded Developments to both the Project management team and to the Foundation as well as the publishing and dissemination of the knowledge and information gained from the Project; (d) strategies
to secure, manage and allocate intellectual property rights associated with the Funded Developments or Background Technology in a way that ensures Global Access while providing incentives for future potential private sector participation; and
(e) anticipated development, commercialization and sustainability strategies during and after the Project to ensure that Global Access can be met. 

You may not materially change the plans and strategies contained in any Global Access documents after they have been approved by the
Foundation without the Foundation’s prior written approval. You will provide the Foundation with updates to the Global Access Strategy during each year of the Project describing any new or modified approaches with respect to Funded Developments
and Background Technology, and related agreements, taking into account any new product, technology, and commercialization developments and/or market information. “Global Access Strategy” means a written document, subject to the
Foundation’s approval, describing how You intend to achieve Global Access given the particular circumstances of the Project. “Project Collaborators” means all current and future subgrantees, subcontractors, partners, agents,
affiliates, or other parties who provides any input to the Project. 
 LICENSE TO THE FOUNDATION 

For the purpose of achieving Global Access, You grant the Foundation a nonexclusive, perpetual, worldwide, royalty-free, fully paid up,
sublicensable license to: make, use, sell, offer to sell, import, distribute, copy, modify, create derivative works, publicly perform and display the Funded Developments and any Background Technology incorporated into a Funded Development or
required to use a Funded Development for the benefit of people in Developing Countries. In the event You demonstrate to the satisfaction of the Foundation that Global Access can best be achieved without such a license (or a license of different
scope), such as by the provision of a Global Access Strategy satisfactory to the Foundation, the Foundation and You will make good faith efforts to modify or terminate this license, as appropriate. As used herein, Developing Countries shall mean any
GAVI-eligible countries as described in Attachment C and any GAVI graduating countries (see http://www.gavi.org/country/). 

  
 Page 6 of 25 

 PUBLICATION 

For the purpose of achieving Global Access, You will seek prompt publication of any Funded Developments consisting of data and results in a
peer-reviewed journal, treatise, or trade publication, as applicable. Publication may be delayed for a reasonable period for the sole purpose of seeking patent protection, provided the patent application is drafted, filed, and managed in a manner
that best furthers the Charitable Purpose. You will also use good faith efforts to ensure that Your subgrantees, and subcontractors, agents, and affiliates, as applicable, likewise seek prompt publication of any Funded Developments consisting of
data and results. 
 PUBLICATION IN PEER-REVIEWED JOURNALS 

If You seek publication of Funded Developments in a peer-reviewed journal, such publication shall be under “open access” terms and
conditions consistent with the Foundation’s Open Access Policy available at: www.gatesfoundation.org/How-We-Work/General-Information/Open-Access-Policy, which may be modified from time to time. 

INTELLECTUAL PROPERTY REPORTING 

During the term of this Agreement and for [**] years after, You will submit upon request annual intellectual property reports related to the
Funded Developments, Background Technology, and any related agreements using the Foundation’s templates or forms, which the Foundation may modify from time to time. 

SUBGRANTS AND SUBCONTRACTS 
 SUBGRANTS
AND SUBCONTRACTS 
 You have the exclusive right to select subgrantees and subcontractors to assist with the Project. 

RESPONSIBILITY FOR OTHERS 

You are responsible for (a) all acts and omissions of any of Your trustees, directors, officers, employees, subgrantees, subcontractors,
contingent workers, agents, and affiliates assisting with the Project, and (b) ensuring their compliance with the terms of this Agreement. 

  
 Page 7 of 25 

 PROHIBITED ACTIVITIES 

ANTI-TERRORISM 
 You will
not use funds provided under this Agreement, directly or indirectly, in support of activities (a) prohibited by U.S. laws related to combatting terrorism; (b) with persons on the List of Specially Designated Nationals
(www.treasury.gov/sdn) or entities owned or controlled by such persons; or (c) in or with countries or territories against which the U.S. maintains comprehensive sanctions (currently, Cuba, Iran, (North) Sudan, Syria, North Korea, and
the Crimea Region of Ukraine), including paying or reimbursing the expenses of persons from such countries or territories, unless such activities are fully authorized by the U.S. government under applicable law and specifically approved by the
Foundation in its sole discretion. 
 ANTI-CORRUPTION; ANTI-BRIBERY 

You will not offer or provide money, gifts, or any other things of value directly or indirectly to anyone in order to improperly influence any
act or decision relating to the Foundation or the Project, including by assisting any party to secure an improper advantage. Training and information on compliance with these requirements are available at www.learnfoundationlaw.org. 

POLITICAL ACTIVITY AND ADVOCACY 

You may not use Grant Funds to influence the outcome of any election for public office or to carry on any voter registration drive. You
acknowledge that the Foundation has not earmarked Grant Funds to support lobbying activity or to otherwise support attempts to influence local, state, federal, or foreign legislation. Your strategies and activities, and any materials produced with
Grant Funds, must comply with applicable local, state, federal, or foreign lobbying law. You agree to comply with all lobbying, gift, and ethics rules applicable to the Project. 

PUBLICITY 
 PUBLICITY BY THE
FOUNDATION 
 The Foundation may include information about the award of this grant, including Your name, in its periodic public reports
and may make such information available on its website and as part of press releases, public reports, speeches, newsletters, tax returns, and other public disclosures. 

PUBLICITY BY YOU 
 You must
obtain the Foundation’s prior written approval before: (a) issuing a press release or other public announcement regarding this grant; and (b) any other public use of the Foundation’s name or logo. Please email Your request to:
grantee.comms@.gatesfoundation.org two weeks in advance to provide the Foundation an opportunity to review and comment. Detailed guidelines are available at: www.gatesfoundation.org/grantseeker/documents/guidelines communications for
grantees.doc. 

  
 Page 8 of 25 

 PUBLICITY BY OTHERS 

You and Your subgrantees, subcontractors, contingent workers, agents, or affiliates may not state or otherwise imply to third parties that the
Foundation directly funds or otherwise endorses their activities. 
 OTHER 

COMPLIANCE WITH LAWS 
 In
carrying out the Project, You will comply with all applicable laws, regulations, and rules and will not infringe, misappropriate, or violate the intellectual property, privacy, or publicity rights of any third party. 

COMPLIANCE WITH REQUIREMENTS 

You will conduct, control, manage, and monitor the Project in compliance with all applicable ethical, legal, regulatory, and safety
requirements, including applicable international, national, local, and institutional standards (“Requirements”). You will obtain and maintain all necessary approvals, consents, and reviews before conducting the applicable activity.
As a part of Your annual progress report to the Foundation, you must report whether the Project activities were conducted in compliance with all Requirements. 

If the Project involves: 
 a. any
protected information (including personally identifiable, protected health, or third-party confidential), You will not disclose this information to the Foundation without obtaining the Foundation’s prior written approval and all necessary
consents to disclose such information; 
 b. children or vulnerable subjects, You will obtain any necessary consents and approvals unique to
these subjects; and/or 
 c. any trial involving human subjects, You will adhere to current Good Clinical Practice as defined by the
International Council on Harmonisation (ICH) E-6 Standards (or local regulations if more stringent) and will obtain applicable trial insurance. 

Any activities by the Foundation in reviewing documents and providing input or funding does not modify Your responsibility for determining and
complying with all Requirements for the Project. 

  
 Page 9 of 25 

 RELIANCE 

You acknowledge that the Foundation is relying on the information You provide in reports and during the course of any due diligence conducted
prior to the Start Date and during the term of this Agreement. You represent that the Foundation may continue to rely on this information and on any additional information You provide regarding activities, progress, and Funded Developments. 

INDEMNIFICATION 
 If the
Project involves clinical trials, trials involving human subjects, post-approval studies, field trials involving genetically modified organisms, experimental medicine, or the provision of medical/health services (“Indemnified
Activities”), You will indemnify, defend, and hold harmless the Foundation and its trustees, employees, and agents (“Indemnified Parties”) from and against any and all demands, claims, actions, suits, losses, damages
(including property damage, bodily injury, and wrongful death), arbitration and legal proceedings, judgments, settlements, or costs or expenses (including reasonable attorneys’ fees and expenses) (collectively, “Claims”)
arising out of or relating to the acts or omissions, actual or alleged, of You or Your employees, subgrantees, subcontractors, contingent workers, agents, and affiliates with respect to the Indemnified Activities. You agree that any activities by
the Foundation in connection with the Project, such as its review or proposal of suggested modifications to the Project, will not modify or waive the Foundation’s rights under this paragraph. An Indemnified Party may, at its own expense, employ
separate counsel to monitor and participate in the defense of any Claim. Your indemnification obligations are limited to the extent permitted or precluded under applicable federal, state or local laws, including federal or state tort claims acts,
the Federal Anti-Deficiency Act, state governmental immunity acts, or state constitutions. Nothing in this Agreement will constitute an express or implied waiver of Your governmental and sovereign immunities, if any. 

INSURANCE 
 You will
maintain insurance coverage sufficient to cover the activities, risks, and potential omissions of the Project in accordance with generally-accepted industry standards and as required by law. You will ensure Your subgrantees and subcontractors
maintain insurance coverage consistent with this section. 
 TERM AND TERMINATION 

TERM 
 This Agreement
commences on the Start Date and continues until the End Date, unless terminated earlier as provided in this Agreement. 
 TERMINATION

 The Foundation may modify, suspend, or discontinue any payment of Grant Funds or terminate this Agreement if: (a) the Foundation is
not reasonably satisfied with Your progress on the Project; (b) there are significant changes to Your leadership or other factors that the Foundation reasonably believes may threaten the Project’s success; (c) there is a change in
Your control; (d) there is a change in Your tax status; or (e) the Project is no longer aligned with the programmatic strategy; (f) You fail to comply with this Agreement. 

  
 Page 10 of 25 

 RETURN OF FUNDS 

Any Grant Funds that have not been used for, or committed to, the Project upon expiration or termination of this Agreement must be returned
promptly to the Foundation, applied to another Foundation-funded project (current or under consideration), or applied to another mutually-agreed upon charitable project, as directed in writing by the Foundation. Any Income that has not been used
for, or committed to, the Project must be either applied to another Foundation-funded project (current or under consideration) or applied to another mutually-agreed upon charitable project, as directed in writing by the Foundation. 

RECORD KEEPING 
 You will
maintain adequate accounting records related to the Project. You will make such records available to enable the Foundation to monitor and evaluate how Grant Funds have been used. 

SURVIVAL 
 A Party’s
obligations under this Agreement will be continuous and survive expiration or termination of this Agreement as expressly provided in this Agreement or otherwise required by law or intended by their nature. 

GENERAL 
 ENTIRE AGREEMENT AND
AMENDMENTS 
 This Agreement contains the entire agreement of the Parties and supersedes all prior and contemporaneous agreements
concerning its subject matter. Except as specifically permitted in this Agreement, no modification, amendment, or waiver of any provision of this Agreement will be effective unless in writing and signed by authorized representatives of both Parties.

 NOTICES AND APPROVALS 

Written notices, requests, and approvals under this Agreement must be delivered by mail or email to the other Party’s primary contact
specified on the Agreement Summary & Signature Page, or as otherwise directed by the other Party. 
 SEVERABILITY 

Each provision of this Agreement must be interpreted in a way that is enforceable under applicable law. If any provision is held unenforceable,
the rest of the Agreement will remain in effect. 

  
 Page 11 of 25 

 ASSIGNMENT 

You may not assign, or transfer by operation of law or court order, any of Your rights or obligations under this Agreement without the
Foundation’s prior written approval. This Agreement will bind and benefit any permitted successors and assigns. 
 COUNTERPARTS AND
ELECTRONIC SIGNATURES 
 Except as may be prohibited by applicable law or regulation, this Agreement and any amendment may be signed in
counterparts, by facsimile, PDF, or other electronic means, each of which will be deemed an original and all of which when taken together will constitute one agreement. Facsimile and electronic signatures will be binding for all purposes. 

  
 Page 12 of 25 

 GRANT AGREEMENT 

Investment ID OPP1170296 

ATTACHMENT C 

DEVELOPING COUNTRIES 
  

					
	Afghanistan	  	Ghana	  	Nicaragua
	Angola	  	Guinea	  	Niger
	Armenia	  	Guinea Bissau	  	Nigeria
	Azerbaijan	  	Guyana	  	Pakistan
	Bangladesh	  	Haiti	  	Papua New Guinea
	Benin	  	Honduras	  	Rwanda
	Bhutan	  	India	  	Sao Tome e Principe
	Bolivia	  	Indonesia	  	Senegal
	Burkina Faso	  	Kenya	  	Sierra Leone
	Burundi	  	Kiribati	  	Solomon Islands
	Cambodia	  	Korea DPR	  	Somalia
	Cameroon	  	Kyrgyz Republic	  	Sri Lanka
	Central African Republic	  	Lao PDR	  	Republic of Sudan
	Chad	  	Lesotho	  	South Sudan
	Comoros	  	Liberia	  	Tajikistan
	Congo Republic	  	Madagascar	  	Tanzania
	Cote d’Ivoire	  	Malawi	  	Timor Leste
	Cuba	  	Mali	  	Togo
	Democratic Republic of	  	Mauritania	  	Uganda
	Congo	  	Moldova	  	Ukraine
	Djibouti	  	Mongolia	  	Uzbekistan
	Eritrea	  	Mozambique	  	Viet Nam
	Ethiopia	  	Myanmar	  	Yemen
	Gambia	  	Nepal	  	Zambia
	Georgia	  		  	Zimbabwe

 Certain countries in this Attachment C may be subject to U.S. comprehensive embargo restrictions at present or in the future.
The Parties acknowledge that such restrictions could preclude one or both Parties’ ability to include such countries in any efforts under this GACA. 

  
 Page 13 of 25 

 

 
 Innovative Technology Solutions 

The Innovative Technology Solutions (ITS) team has a unique process and approach to making and managing investments. Please note that other foundation
investments in which you may also be involved will not use the same process and approach. 
 PROJECT INFORMATION - GRANTS 

The purpose of this document is for you to provide organizational and project details to support your proposal to the foundation. 

 

													
	 Foundation Information
	  				 			
	 Opportunity ID
	  	 	OPP1170296	 	 			
	 Program Officer
	  	 	[**]	 	 	 	Program Coordinator	 	 	 	[**]	 
				
	 General Information
	  				 				 			
	Investment Title	  	 	RSV Pre-Clinical Program	 
	Short Description	  	 

	Discovery, lead selection, pre-clinical development, and IND-enabling
toxicology studies for monoclonal antibodies (mAbs) targeting
respiratory syncytial virus (RSV). Goal is to achieve a product profile
that
supports Global Access objectives (e.g. low-cost, single dose
prophylaxis).	 
 
 
 
 
	Organization	  	 	Arsanis, Inc.	 
	Investment Duration (months)	  	 	30	 	 				 			
	Requested Amount (U.S.$)	  	 	$8.8 Million	 	 	 	Total Project Cost (U.S. $)	 	 	 	$9.4 Million	 
	Organization Legal Name1	  	 	Arsanis, Inc.	 
	 Mailing Address
	  				 				 			
	 Street Address 1
	  	 
	890 Winter
Street	 
 	 	 	Primary Contact Name	 	 	 	[**]	 
	 Street Address 2
	  	 	Suite 230	 	 	 	Primary Contact Title	 	 	 	[**]	 
	 Street Address 3
	  				 	 	Primary Contact Email	 	 	 	[**]	 
	 City
	  	 	Waltham	 	 	 	Primary Contact Phone	 	 	 	[**]	 
	 State / Province
	  	 	MA	 	 				 			
	 Zip / Postal Code
	  	 	02451-1472	 	 	 	Authorized Signer Name	 	 	 	Mike Gray	 
	 Country
	  	 	US	 	 	 	Authorized Signer Title	 	 	 	CFO and CBO	 
	 Website (if applicable)
	  	 	www.arsanis.com	 	 	 	Authorized Signer Email	 	 	 	mike.gray@arsanis.com	 
	
1        Legal
Name will be used in the agreement and should match the name on the bank account that receives the grant funds (assuming fully executed agreement).
	
         

	 Tax Status (if known and applicable)

Refer to Tax Status Definitions
	  	 

 
	Non-Exempt
Organization
 – C Corporation
	 
 
  
	 	 

	Organization’s Total
Revenue for Most
Recent Audited
Financial Year (U.S.$)	 
 
 
 	 	 	No sales revenue	 
	U.S. Employer Identification Number (EIN) (if applicable)	  	 	27-3181608	 	 	 			

  
 Page 14 of 25 

 

 
 Charitable Purpose & Public Description 

Describe the charitable purpose of the project. This statement will be used to inform the public description of this project. Please limit to one
sentence, begin with “to” and do not include a period at the end. Example: “This grant will be used [to fund new schools and assist other organizations in the design of new schools]” 

This grant will be used to fund pre-clinical development of monoclonal antibodies (mAbs) for the prevention of respiratory syncytial virus (RSV) infection in
newborns, which is responsible for over 30 million cases of acute lower respiratory infection and 200,000 deaths per year in the developing world. 

Conduct & Control of the Project 
 In
answering the questions in this section, please consider all Project activities, such as those involving: confidential or protected information (including personally identifiable information or protected health information); the inclusion of
children or vulnerable populations; research involving human subjects; clinical trials; post-approval studies; field trials; experimental medicine; provision of medical services (diagnostic, prophylactic or treatment); product development; use of
genetically modified organisms, human tissue, animals, radioactive isotopes, pathogenic organisms, recombinant nucleic acids, select agents or toxins (www.selectagents.gov), dual-use technology
(http://export.gov/regulation/eg_main_018229.asp), or any substance, organism, or material that is toxic or hazardous; use of aircraft, unmanned vehicle systems, drones or satellites; and the import, export, transfer, approvals, consents,
records, data, specimens, images, and materials related to any of the forgoing. 
  

	1.	Please confirm that your organization: 

  

	 	a)	will maintain the expertise necessary to conduct, control, manage, and monitor all aspects of the Project in compliance with all applicable ethical, legal, regulatory, and safety requirements, including applicable
international, national, local, and institutional standards and policies and is responsible for determining and complying with these requirements and standards; 

 

	 	b)	will not disclose any confidential or protected information to the Foundation without obtaining prior written approval from the foundation and all necessary consents to disclose such information;

  

	 	c)	acknowledges that any activities by the Foundation in reviewing documents, providing input or funding does not modify your organization’s responsibility for determining and complying with all applicable ethical,
legal, regulatory, and safety requirements for the Project in all places; 

  

	 	d)	will maintain insurance coverage sufficient to cover the activities, risks, and potential omissions of the Project in accordance with generally-accepted standards and as required by law (for instance, general,
professional, clinical trial, product liability, medical malpractice, workers’ compensation, or otherwise); 

  

	 	e)	will not transfer any biological materials, chemicals, reagents, hazardous materials or the like to the Foundation. Confirmed     X  

Not confirmed            (please explain) 

 

	2.	Does the Project involve any of the following: clinical trial, other trial involving human subjects, post-approval study, experimental medicine, genetically modified organism, or the provision of medical/health
services? 

  

	 	No	    X  

  

	 	Yes            (If	yes, please list all approvals and consents required for each site and describe the timeframe in which your organization will acquire the necessary approvals and consents.) 

  
 Page 15 of 25 

 

 
  

	3.	Please identify the name of the entity that will be the sponsor/responsible party of any clinical trials, studies involving human subjects, experimental medicine studies, post-approval studies, products, or
regulatory filings contemplated by the Project. Note that the Foundation will not serve as the sponsor/responsible party nor accept delegation of any of these responsibilities. If the Project will not involve such activities, please indicate not
applicable or N/A below. 

  

	Arsanis,	Inc. 

 Global Access & Open Access 

In order to establish that the projects we fund are charitable and will have a positive impact on the intended beneficiaries of our work, the foundation
requires the projects it funds be conducted and managed in a manner that ensures Global Access and Open Access. 
 “Global
Access” is a foundation policy requiring that: (a) the knowledge and information gained from the project will be promptly and broadly disseminated; and (b) the Funded Developments will be made available and accessible at an
affordable price (i) to people most in need within developing countries, or (ii) in support of the U.S. educational system and public libraries, as applicable to the project. 

“Funded Developments” means the products, services, processes, technologies, materials, software, data, other innovations, and
intellectual property resulting from the project, including modifications, improvements, and further developments to Background Technology. 

“Background Technology” means any and all products, services, processes, technologies, materials, software, data, or other
innovations, and intellectual property created by You or a third party prior to or outside of the project used as part of the project. 

Additional information about Global Access (including examples and case studies) can be found at
http://globalaccess.gatesfoundation.org/. 
 “Open Access”is a foundation policy that sets the requirements, terms
and conditions for publication of Funded Developments in a peer-reviewed journal. Additional Information on the foundation’s Open Access Policy for peer-reviewed publications and underlying data can be found at
www.gatesfoundation.org/How-We-Work/General-Information/Open-Access-Policy. Note: the foundation will pay directly for reasonable fees to effect publication on “open access” terms; such fees should not be included in the
project budget (See the Open Access Policy FAQs for further detail). 
  

	 	a)	Knowledge and Information 

  

	 	Describe	how the knowledge and information gained from the project will be promptly and broadly disseminated (including how you will comply with the foundation’s Open Access Policy, discussed above).

 Arsanis will promptly and broadly disseminate the output of Funded Developments in compliance with the Open Access Policy and Arsanis
internal policies. Our primary approaches are publication in peer-reviewed journals and presentations (e.g. abstracts, oral sessions) at scientific congresses. In some circumstances, timing of disclosures may be gated by the need to provide for
relevant intellectual property protections prior to such disclosures. 
  

	 	b)	Funded Developments (Indicate “not applicable,” as appropriate) 

	 	i.	Describe any Funded Developments that may ultimately result from the project, including any Background Technology that will be used or incorporated in the proposed project. If applicable, briefly explain how the
Funded Developments will be made available and accessible at an affordable price to the intended beneficiaries. The use of commonly-available, off-the-shelf products (such as Microsoft Excel, Adobe, etc.) need not be disclosed.

 Funded Developments that may ultimately result from the project include: 

 

	 	•	 	Monoclonal antibody (mAb) drug candidates targeting RSV infection. 

  

	 	•	 	Pre-clinical data and regulatory filings that support the initiation of human studies of these mAbs. 

  

	 	•	 	Manufacturing know-how for the production of GMP mAb drug product. 

  

	 	•	 	Intellectual property (including patents and know-how) covering the mAbs. 

  
 Page 16 of 25 

 

 
 Background technology that may be incorporated in the project includes: 

 

	 	•	 	Arsanis know-how related to the discovery and optimization of mAbs. 

  

	 	•	 	RSV mAb sequences (patents and know-how) that may be in-licensed by Arsanis from Adimab, LLC upon exercise of the Adimab license described below. 

 

	 	•	 	Technologies (patents and know-how) related to the optimization of RSV mAbs in-licensed by Arsanis from third parties. 

  

	 	•	 	Technologies (patents and know-how) related to the manufacture of RSV mAbs in-licensed by Arsanis from third parties. 

  

	 	ii.	Please confirm that you will make the Funded Developments – including any Background Technology incorporated into or required to use the Funded Developments – available to achieve the proposed
project’s goals and Global Access. If you foresee any obstacles to achieving Global Access (e.g., third party rights, broad access, time frame, affordability) please briefly summarize the obstacles and the specific steps that you will take to
address them. 

 Arsanis will make the Funded Developments available to achieve the project’s goals and Global Access as agreed upon
with BMGF. 
 Potential obstacles include: 
 [**] 

 

	 	c)	If one or more of the following applies, please click the following link to complete an Intellectual Property (IP) Report: 

 

	 	•	 	Creation of Funded Developments will likely involve new IP rights (Note: copyrights in works intended to be published in accordance with the Open Access Policy need not be disclosed); 

 

	 	•	 	Use of Background Technology requires access to existing IP rights; or 

  

	 	•	 	For-Profit entities are engaged in the project. 

 Note: For login purposes, please use the email
address to which this Proposal Narrative was sent. To delegate permissions to another member of your project team, or for any questions regarding the IP Report, please contact GlobalAccess@gatesfoundation.org. 

  
 Page 17 of 25 

 

 
 Privacy and Non-Confidentiality Notice 

The foundation is required by the IRS to publish a list of its grants. We may also provide a general description of our grants and contracts on our web
sites, in press releases, and in other marketing materials. Subject to the foundation’s Privacy Policy, the foundation may also share information you provide to us (either orally or in writing) with third parties, including external
reviewers, key partners and co-founders. This document is subject to the foundation’s Terms of Use. 

  
 Page 18 of 25 

 

 
 RSV Pre-Clinical Program Proposal 

Prepared by: Arsanis, Inc. 
 Updated
February 8, 2017 
  
 Confidential
Materials omitted and filed separately with the Securities and Exchange Commission. 
 A total of 22 pages were omitted. [**] 

ARSANIS NON-CONFIDENTIAL REDACTED DRAFT 

  
 Page 19 of 25 

	
	

  
 Page 20 of 25 

	
	

  
 Page 21 of 25 

 Confidential Materials omitted and filed separately with the Securities and Exchange Commission. A total of 32
pages were omitted. [**] 

  
 Page 22 of 25 

 

 
 AMENDMENT 1 to GRANT AGREEMENT Investment ID OPP1170296 

AMENDMENT SUMMARY & SIGNATURE PAGE 
  

			
	AMENDMENT INFORMATION
		
	Agreement to be Amended:	  	Grant agreement between the Bill & Melinda Gates Foundation and Arsanis Inc, effective February 20, 2017, and bearing Investment ID OPP1170296
		
	Amendment Purpose:	  	No-cost Extension and Revised Payment & Reporting Schedule
		
	Amendment Date:	  	Date of this email
		
	New End Date:	  	October 31, 2019
		
	This Amendment includes and incorporates into the Agreement by this reference:	  	 This Amendment Summary & Signature Page and:

- Attachment A-1

 THIS AMENDMENT amends, and is made part of, the above-referenced Agreement and is effective as 

of the date of this email. Capitalized terms not defined in this Amendment will have the meaning provided in the Agreement. Except as modified by this
Amendment, all other terms and conditions of the Agreement remain in full force and effect. In the event of a conflict between the Agreement and this Amendment, the terms of this Amendment will prevail. 

As provided in the Agreement, Your countersignature is not required. 

ATTACHMENT A-1 
 TERM 

This Amendment approves Your request for a no-cost extension to the Agreement. The term of the 

Agreement is extended to the new End Date specified on the Amendment Summary & Signature Page. 

UPDATED REPORTING PAYMENT SCHEDULE 

This Amendment notifies You that the reporting and payment schedule for Your grant has changed. 

Your updated Reporting & Payment Schedule is deleted and replaced with the following: 

 

									
	 REPORTING & PAYMENT
SCHEDULE

	 Investment
Period
	  	 Target, Milestone, or Reporting

Deliverable
	  	 Due By
	  	 Payment Date
	  	 Payment Amount
(U.S.$)

		  	Paid	  		  	[**]	  	[**]
	Start Date to End Date	  	Quarterly Financial & Progress Updates	  	Quarterly	  		  	
		  	Global Access Strategy satisfactory to the Foundation	  	[**]	  	[**]	  	[**]
		  	Updated Financial Statements	  	  	  
		  	Product Development Summary and Status - Candidate Target Product Profile, Revised Budget, including Sub-award Budget	  	  	  
		  	[**]	  	  	  

  
 Page 23 of 25 

 

 
  

									
	 [**]
	  	[**]	  	[**]	  		  	
		  	[**]	  	[**]	  	[**]	  	[**]
	 [**]
	  	[**]	  	[**]	  		  	

  
 Page 24 of 25 

 

 
  

							
		  	[**]	  	[**]	  	
	 Start Date to End Date
	  	Final Report	  	[**]	  	
	 Amended Total Grant Amount
	  	$9,330,878.00

  
 Page 25 of 25

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