Document:

Exhibit 10.1

 

EXECUTION COPY

 

LICENSE
AND DEVELOPMENT AGREEMENT

 

This License and Development Agreement
(“Agreement”) is made and entered into as of this June 5, 2015 (the “Effective Date”) by and between Bayer
HealthCare LLC, with offices at 100 Bayer Blvd., Whippany, NJ 07981 (“Bayer”), and Acura Pharmaceuticals, Inc., with
offices at 616 N. North Court, Palatine IL 60067 (“Acura”). Bayer and Acura each are referred to herein as a “Party”
and collectively as the “Parties.”

 

WITNESSETH:

 

WHEREAS,
Acura has developed Impede® Technology designed to prevent extraction of pseudoephedrine from tablets and to disrupt the direct
conversion of pseudoephedrine from tablets into methamphetamine;

 

WHEREAS,
Bayer and its Affiliates have substantial expertise in the distribution, sales and marketing of healthcare products worldwide;

 

WHEREAS,
Acura wishes to grant to Bayer, and Bayer wishes to obtain, the rights to (i) make, have made, distribute, have distributed, sell,
have sold, market, have marketed, commercialize, and have commercialized the Developed Product(s) utilizing the Impede® Technology
in the Field in the Territory, on the terms and conditions set forth herein (as each such term in defined herein);

 

NOW THEREFORE,
in consideration of the foregoing premises and the mutual promises, covenants and conditions contained in this Agreement, the Parties
agree as follows:

 

ARTICLE I – DEFINITIONS

 

		1.1	“Affiliate” means any corporation or other entity, which directly or indirectly
controls, is controlled by or is under common control with a Party. A corporation or other entity shall be regarded as in control
of another corporation or entity if it owns or directly or indirectly controls more than Fifty Percent (50%) of the voting stock
or other ownership interest of the other corporation or entity, or if it possesses, directly or indirectly, the power to direct
or cause the direction of the management and policies of the corporation or other entity or the power to elect or appoint more
than Fifty Percent (50%) of the members of the governing body of the corporation or other entity. Notwithstanding the foregoing,
a private equity or venture capital firm with an ownership interest in an entity shall not be an Affiliate by reason of such ownership
and portfolio companies of a private equity firm or a venture capital firm shall not be Affiliates or a Party by virtue of the
private equity firm or venture capital firm being Affiliates of a Party.

 

*****Confidential treatment requested pursuant to a request
for confidential treatment filed with the Securities and Exchange Commission; omitted portions have been separately filed with
the Commission.

 

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		1.2	“Allergy Product” means [*****].

 

		1.3	“Applicable Law” means, with respect to any Person, any domestic or foreign,
federal, state or local statute, treaty, law, ordinance, rule, regulation, administrative interpretation, order, writ, injunction,
judicial decision, decree or other requirement of any governmental authority, including any rules, regulations or other requirements
of the Regulatory Authorities in the Territory, applicable to such Person or any of such Person’s respective properties,
assets, officers, directors, employees, consultants or agents.

 

		1.4	“Budget” is the budget for the proposed development of the Developed Product
as set forth in Exhibit B, and as amended in writing by the DC.

 

		1.5	“Commercialization Condition” [*****].

 

		1.6	“Commercially Reasonable Efforts” means with respect to a Party, the efforts
and resources which would be used (including the promptness in which such efforts and resources would be applied) by that Party
consistent with its normal business practices and in compliance with Applicable Law and the exercise of prudent scientific and
business judgment, which in no event shall be less than the level of efforts and resources standard in the pharmaceutical industry
for a company similar in size and scope to such Party, with respect to a product or potential product at a similar stage in its
development and with similar market potential or product life cycle taking into account efficacy, safety, commercial value, the
competitiveness of alternative products of Third Parties that are in the marketplace, and the Patent Rights and other proprietary
position of such product.

 

		1.7	“Confidential Information” is defined in Section 7.1 herein below.

 

		1.8	“Competing Product” means [*****].

 

		1.9	“Control” means, with respect to Intellectual Property Rights, ownership or
the possession of the ability by license or otherwise to assign or grant a license or sublicense to or disclose such Intellectual
Property Rights without violating the terms of any agreement or other arrangement, express or implied, with any Third Party.

 

		1.10	“DC” means a Development Committee.

 

		1.11	Delivery” has the meaning set forth in Section 5.2.

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission;
omitted portions have been separately filed with the Commission.

 

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		1.12	“Development Plan” means the plan for the development of the Developed Product
set forth in Exhibit A, as the same may be amended by the Parties in writing.

 

		1.13	“Developed Product(s)” means a [*****] product [*****].

 

		1.14	“Effective Date” has the meaning set forth above.

 

		1.15	“FDA” means the United States Food and Drug Administration, or any successor
thereto.

 

		1.16	“Field” means over-the-counter (non-prescription) (“OTC”)
and prescription (“Rx”) products.

 

		1.17	“FTE Expense” means [*****].

 

		1.18	“GAAP” means generally accepted accounting principles in effect in the United
States from time to time applied on a consistent basis.

 

		1.19	“Gross Sales” means [*****].

 

		1.20	“Impede® Patent Rights” means [*****].

 

		1.21	“Impede® Technology” means [*****].

 

		1.22	“Information” means any development data, results, records, reports,
and technical information and information of any type whatsoever, in any tangible or intangible form, including, without limitation,
technical, reports, specifications, test data (including pharmacological, biological, chemical, biochemical, toxicological, preclinical
and clinical test data), analytical and quality control data, stability data, other study data and procedures.

 

		1.23	“Infringing Competing Product” means [*****].

 

		1.24	“Intellectual Property Rights” means Know-How, registered trademarks,
trademark applications, unregistered trademarks, trade dress, copyrights, and Patent Rights.

 

		1.25	“Know-How” means all Information that is Controlled by a Party, including
but not limited to ideas, concepts, discoveries, inventions, developments, and improvements.

 

		1.26	“Know-How Royalty Payment” is defined in Section 4.2.1 

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		1.27	“License” has the meaning set forth in Section 3.1.

 

		1.28	“Major Foreign Markets” means [*****].

 

		1.29	“Milestone Payments” is defined in Section 4.1.

 

		1.30	“Net Sales” means [*****].

 

		1.31	“Non-Delivery Notice” is defined in Section 5.2.

 

		1.32	“Patent Rights” means patents and patent applications, and all divisionals,
continuations, continuations in part, reissues, extensions, supplementary protection certificates and foreign counterparts thereof.

 

		1.33	“Person” means an individual, a corporation, a general partnership, a
limited partnership, a limited liability company, a limited liability partnership, an association, a trust or any other entity
or organization.

 

		1.34	“Pilot BE Study” means in vivo pharmacokinetic studies designed to test
bioequivalence on [*****] meeting the criteria of Exhibit D.

 

		1.35	“PSE” means pseudoephedrine or a pharmaceutically acceptable salt thereof.

 

		1.36	“Regulatory Approval” means the license or final FDA, or equivalent foreign
governmental authority, marketing approval necessary as a prerequisite for marketing the Developed Product in a country in the
Territory.

 

		1.37	“Regulatory Approval Application” means shall mean any filing(s) made with the
Regulatory Authority in any country in the Territory for Regulatory Approval of the marketing, manufacture and sale (and pricing
when applicable) of the Developed Product in such country.

 

		1.38	“Regulatory Authority” means the FDA in the U.S., and any health regulatory
authority(ies) in any other country in the Territory that is a counterpart to the FDA and has responsibility for granting regulatory
approval for the marketing, manufacture, and sale of the Developed Product in such country, including, but not limited to, pricing
and reimbursement approvals, and any successor(s) thereto, as well as any state or local health regulatory authorities having jurisdiction
over any activities contemplated by the Parties.

 

		1.39	“Right of First Negotiation Product” is defined in Section 3.7.

 

*****Confidential treatment
requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted portions
have been separately filed with the Commission.

 

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		1.40	“Royalty Payments” means the Standard Royalty Payments and the Know-how
Royalty Payments.

 

		1.41	“Royalty Report” is defined in Section 4.3.

 

		1.42	“Standard Royalty Payment” is defined in Section 4.2.1 

 

		1.43	“Target Product Profile” is defined in Exhibit D.

 

		1.44	“Term” has the meaning set forth in Section 2.1.

 

		1.45	“Territory” means the world.

 

		1.46	“Third Party” means any entity other than Acura and its Affiliates and Bayer
and its Affiliates.

 

		1.47	“Valid” means, with respect to a Impede® Patent Rights in a particular
country, such Impede® Patent Rights have not (A) expired or been cancelled, (B) been declared invalid or unenforceable
by a decision of a court or other appropriate body of competent jurisdiction, from which no appeal is or can be taken, (C) been
admitted to be invalid or unenforceable through reissue, disclaimer or otherwise, or (D) been abandoned or disclaimed either affirmatively
or by operation of law.

 

ARTICLE II-TERM AND TERMINATION

 

		2.1	Term and Expiration. The Term of this Agreement shall be on a country-by-country basis and,
with respect to each country, will begin on the Effective Date and will expire on the later of the date that (i) the Impede®
Patent Rights in such country are not Valid or do not claim the Developed Product; or (ii) is five years post launch of the Developed
Product in such country in which there are not any Impede® Patent Rights that are both Valid and claim the Developed
Product. The Agreement shall expire in its entirety when the Term has expired for all countries.

 

		2.2	Termination

 

		2.2.1	Before Delivery, Bayer may terminate this Agreement in its entirety immediately upon written notice
to Acura. After Delivery, Bayer may terminate this Agreement at will upon six (6) months’ notice to Acura.

 

		2.2.2	Acura may terminate this Agreement at any time upon sixty (60) days’ written notice to Bayer
if Bayer does not launch the Developed Product in the United States [*****] Nothing in this Section 2.2.2 shall relieve Bayer of
its obligations to use Commercially Reasonable Efforts to commercialize the Developed Product.

 

*****Confidential treatment requested
pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted portions have been
separately filed with the Commission.

 

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		2.2.3	Acura may terminate this Agreement at any time [*****] if Bayer suspends commercialization of the
Developed Product in the United States for more than [*****]. Nothing in this Section 2.2.3 shall relieve Bayer of its obligations
to use Commercially Reasonable Efforts to commercialize the Developed Product.

 

		2.2.4	Acura may terminate this Agreement at any time upon sixty (60) days’ written notice to Bayer
if Bayer for an aggregate period greater than [*****] has not conducted any development of the Developed Product for the United
States prior to Regulatory Approval for the United States, [*****].

 

		2.2.5	With respect to each Major Foreign Market, if Bayer does not (i) initiate development of the Developed
Product for such Major Foreign Market within [*****].

 

		2.2.6	If Bayer or an Affiliate of Bayer files or has a Regulatory Approval Application pending or seeks
Regulatory Approval of, or holds, directly or indirectly, including by way of a license, a Regulatory Approval for, or launches
or assist a Third Party in the launch of an Infringing Competing Product or Competing Product in a country in the Territory, Acura
may elect to terminate this Agreement with respect to such country only. Bayer shall provide written notice to Acura within [*****]
days after (i) it or an Affiliate files or has pending a Regulatory Approval application for a Competing Product or an Infringing
Competing Product or (ii) after receipt by it or an Affiliate of Bayer of receipt, or holding of a Regulatory Approval for the
Developed Product.

 

		2.2.7	Either Party may terminate the Agreement in its entirety by giving written notice of termination
at any time, if the other Party fails to fulfill or breaches any material term or condition of this Agreement, and does not remedy
the failure or breach within [*****] of receipt of written notice specifying such failure or breach given by the other Party; or
if the other Party becomes insolvent, makes an assignment for the benefit of its creditors, is subject to proceedings in voluntary
or involuntary bankruptcy instituted on behalf of or against such Party, goes into liquidation or has a receiver or trustee appointed
for all or substantially all of its property.

 

		2.3	Consequences of Expiration. Upon expiration of this Agreement with respect to a country,
Bayer shall retain a non-exclusive, perpetual, irrevocable, fully paid-up and royalty-free license to, have made, sell, promote,
or otherwise exploit the Developed Product in such country.

 

*****Confidential treatment requested
pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted portions have been
separately filed with the Commission.

 

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		2.4	Consequences of Termination. Upon termination of this Agreement with respect to one or more
countries: (i) all of Bayer’s licenses with respect to Acura’s trademarks and the Impede® Technology with respect
to the terminated countries shall terminate; (ii) Bayer shall retain its Regulatory Approvals with respect to the Developed Product
for the terminated countries; (iii) if the termination is by Bayer under Section 2.2.1, or by Acura under Sections 2.2.2, 2.2.3,
2.2.4, 2.2.5, 2.2.6 or 2.2.7, Acura’s non-compete contained in Sections 3.5 and 3.6 shall terminate immediately with respect
to the terminated countries; (vi) if the termination of this Agreement is for all countries (e.g., in its entirety), Bayer shall
pay [*****]; and (v) Bayer’s right of reference under Section 3.4 with respect to such terminated countries shall terminate
if such termination occurs prior to Delivery under Section 2.2.1.

 

		2.5	Accrued Rights; Surviving Obligations.

 

		2.5.1	Termination, relinquishment or expiration of this Agreement for any reason shall be without prejudice
to any rights that shall have accrued to the benefit of either Party prior to such termination, relinquishment or expiration. Such
termination, relinquishment or expiration shall not relieve either Party from obligations that are expressly indicated to survive
termination or expiration of this Agreement.

 

		2.5.2	All of the Parties’ rights and obligations under Sections 2.3, 2.4, 2.5, 3.5, 4.3, 4.5.2,
4.7, 4.8, 5.6.5, and Articles 6, 7, 8, 9, 11, and 12, shall survive termination, relinquishment or expiration of this Agreement,
and all other provisions reasonable construed to survive shall also survive termination or expiration. Where a provision specifies
a survival period, such provision shall survive only during such survival period.

 

ARTICLE III-LICENSE AND COMMERCIALIZATION

 

		3.1	License. Acura hereby grants Bayer an exclusive (even as to Acura), sub-licensable (subject
to Section 3.8), royalty-bearing right and license under the Impede® Patent Rights to develop, manufacture, have manufactured,
distribute, have distributed, sell, have sold, market, have marketed, commercialize and have commercialized the Developed Product(s)
in the Field in the Territory.

 

		3.2	No Other Rights and Retained Rights. This Agreement confers no right, license or interest
by implication, estoppel, or otherwise under any Patent Rights, Confidential Information, Know-How or other Intellectual Property
(including but not limited to trade secrets, formulations, manufacturing processes, data) that was owned by a Party prior to signing
the Agreement except as expressly set forth in this Article III. Each Party hereby expressly retains and reserves all rights
and interests with respect to patents, Confidential Information, technology or other intellectual property rights not expressly
granted to the other Party hereunder.

 

*****Confidential treatment requested
pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted portions have been
separately filed with the Commission.

 

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		3.3	Bayer to use CRE. Bayer shall use Commercially Reasonable Efforts to market and sell Developed
Product in the United States and Major Foreign Markets, after obtaining Regulatory Approval for the Developed Product in such country;
provided, however, that (i) Bayer shall have sole discretion and control as to the manner and extent of such commercialization
of such Developed Product and (ii) subject to Section 2.2 and 4.5.1, Bayer shall have the right to postpone or delay the commercial
launch of such Developed Product or discontinue, interrupt or cease the marketing and sale of such Developed Product in Territory
if the commercialization of Developed Product is reasonably determined by Bayer to be economically unviable or in the event litigation
is pending or threatened with respect to such Developed Product. During the Term, Bayer shall have the sole obligation and responsibility,
and at its sole cost and expense, for all aspects of manufacturing, including without limitation, testing packaging and labelling
the Developed Product, and any costs associated with storage, release and Third Party logistics. As part of such responsibilities,
Bayer shall have the sole responsibility to obtain or to coordinate with and provide to its contract manufacturer such information
and materials as shall be reasonably necessary to obtain sufficient quota for active pharmaceutical ingredients from the Drug Enforcement
Administration, and similar foreign agencies. Bayer shall be solely responsible at its cost and expense for any recalls or withdrawals
of Developed Product.

 

		3.4	Right of Reference. Acura grants Bayer a right of reference to [*****].

 

		3.5	Non-Compete. Acura will not file a Regulatory Approval Application or seek Regulatory Approval
of or launch or assist a Third Party in the launch of an Infringing Competing Product or a Competing Product in a country in the
Territory [*****].

 

		3.6	Allergy Product Development. Acura will not file a Regulatory Approval Application or seek
Regulatory Approval of or launch or assist a Third Party in the launch of an Allergy Product containing Acura’s Impede®
Technology [*****].

 

		3.7	Right of First Negotiation Product. As used in this Agreement, “Right of First Negotiation
Product” means a product containing the following as its only active pharmaceutical ingredients: [*****]. If Acura [*****]
and in each case Acura determines to license, develop, collaborate with respect to or sell such Right of First Negotiation Product,
then it will send Bayer written notice of same, before offering such Right of First Negotiation Product to any Third Party. [*****].
This Section 3.7 shall not survive termination or expiration of this Agreement.

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		3.8	Sublicenses. Bayer shall not grant a sublicense in the United States of the licenses granted
to it under Section 3.1, to a Third Party to market or sell the Developed Product without the consent of Acura, such consent not
be unreasonably withheld. Bayer may grant sublicenses outside of the United States of the licenses granted to Bayer under Section
3.1, to a Third Party to market or sell the Developed Product (other than sublicenses granted to Third Parties acting as distributors
or wholesalers or to Third Parties providing products or non-marketing/selling services to or on behalf of Bayer or its Affiliates),
provided, however, [*****].

 

ARTICLE IV-MILESTONES AND
ROYALTIES

 

		4.1	Milestone Payments. Bayer shall make the following non-refundable, non-creditable milestone
payments (“Milestone Payments”), and provide the following notices, to Acura:

 

		4.1.1	Within [*****], Bayer shall pay Acura [*****].

 

		4.1.2	Within [*****] Bayer shall pay Acura [*****].

 

		4.1.3	Within [*****] Bayer shall pay Acura [*****].

 

		4.1.4	Within [*****] Bayer shall pay Acura [*****].

 

		4.1.5	The Milestone Payments provided in each of Sections 4.1.2, 4.1.3 and 4.1.4 shall be reduced by
[*****] if [*****].

 

		4.2	Royalties and Other Payments. The following payments shall be payable by Bayer to Acura
for sales made during each calendar quarter and payment will be remitted within [*****] after the end of the quarter to which it
relates.

 

		4.2.1	Standard Royalty Payment. For each country in the Territory during any period of the Term
in which (a) a claim under any Impede® Patent Right is Valid in a country and (b) a Third Party does not sell a Competing Product
in such country, Bayer shall pay to Acura a royalty of [*****]. Such royalty shall be payable for sales made during each calendar
quarter and payment will be remitted [*****]. The royalty payment under this section 4.2.1 is referred to as the “Standard
Royalty Payment.”

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		4.2.2	Know-How Royalty Payment. For each country during any period of the Term in which (a) Impede®
Patent Rights do not exist or are not Valid in a country or (b) a Third Party sells a Competing Product in such country, Bayer
shall pay Acura a quarterly royalty payment of [*****]. Bayer shall only be required to make payments under this Section 4.2.2
with respect to a country (determined on a country-by-country basis) until [*****]. Bayer shall provide Acura a detailed written
explanation if it makes any Know-How Payments due to a Competing Product within [*****] of reaching such determination. The royalty
payment under this Section 4.2.2 is referred to as the “Know-How Royalty Payment.”

 

		4.3	Royalty Reports. Bayer shall prepare in respect of each calendar quarter a report (“Royalty
Report”) that shows for that calendar quarter the [*****]. The Royalty Report shall be in the form of Exhibit E.

 

		4.4	Royalty Stacking. The Royalty Payments with respect to a country will be reduced by [*****],
but for any calendar quarter shall not reduce the Royalty Payments payable to Acura with respect to such country to less than [*****].

 

		4.5	Minimum Annual Royalty.

 

		4.5.1	Notwithstanding the calculation of the Royalty Payments under Section 4.2, commencing [*****],
the aggregate Royalty Payments in the Territory payable by Bayer to Acura in any calendar year during the Term of this Agreement
shall not be less than [*****] (the “Annual Minimum Royalty Amount”). In the first year in which the minimum Royalty
Payments are payable, the minimum royalty shall be pro-rated by dividing (A) the number of days during such calendar year in which
such minimum royalty obligations exist by (B) 365 and multiplying the result by the Annual Minimum Royalty Amount. Similarly in
the calendar year of expiration, the minimum royalty shall equal (A) the number of days in such calendar year prior to expiration
divided by (B) 365 and multiplying the result by the Annual Minimum Royalty Amount. In addition, if a Commercialization Condition
exists and Bayer is not commercializing the Developed Product then for such calendar year the minimum royalty shall be reduced
(not below zero) by [*****].

 

		4.5.2	Within [*****], Bayer shall pay Acura any difference between Annual Minimum Royalty Amount (as
the same may be prorated pursuant to section 4.5.1) and the royalties actually paid during the preceding calendar year, if applicable.

 

		4.6	Pricing. Bayer shall have sole discretion to determine the price, terms and conditions of
sales of Developed Product(s) to Bayer’s customers. Bayer shall not price the Developed Product in any country for any transaction
[*****].

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

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		4.7	Currency. All payments required under this Agreement shall be made in U.S. dollars, regardless
of the country(ies) in which sales are made or expenses are incurred, via wire transfer of immediately available funds to an account
designated in writing by Acura. Whenever, for the purpose of calculating any sums due under this Agreement, conversion from any
foreign currency shall be required, such conversion shall be made as follows: the amounts shall be converted into United States
dollars using the average rate of exchange for such currencies for the relevant period, such exchange rate shall be the exchange
rate taken from The Wall Street Journal as published on the last day of the relevant period for which payments are due, or such
other publication as may be agreed between the Parties from time to time.

 

4.8Taxes.In
the event that a Party is mandated under the laws of a country to withhold any tax to the tax or revenue authorities in such country
in connection with any payment to the other Party, such amount shall be deducted from the payment to be made by such withholding
Party, provided, however, that the withholding Party shall take reasonable and lawful actions, at the other Party’s sole
cost, to avoid and minimize such withholding and promptly notify the other Party so that the other Party may take lawful actions
to avoid and minimize such withholding. The withholding Party shall promptly furnish the other Party with copies of any tax certificate
or other documentation evidencing such withholding as necessary to satisfy the requirements of the United States Internal Revenue
Service related to any application by such other Party for foreign tax credit for such payment. Each Party agrees to cooperate
with the other Party in claiming exemptions from such deductions or withholdings under any agreement or treaty from time to time
in effect. All amounts payable under this Agreement and not paid within [*****] of when due in accordance with the provisions hereof
shall bear interest from the due date until paid at the rate equal to [*****]. Unless otherwise stated all dollar amounts in this
Agreement are in United States dollars.

 

ARTICLE V-DEVELOPMENT/REGULATORY

 

		5.1	Development. Bayer and Acura shall jointly develop the Developed Product pursuant to the
Development Plan attached hereto as Exhibit A. Acura will use Commercially Reasonable Efforts to [*****]. Any activity not
specifically assigned to Acura shall be the responsibility of Bayer. Under no circumstances will Acura be responsible for [*****].
Bayer shall be responsible for all costs and expenses (including Acura’s FTE Expense), for performing all Developed Product
development activities, whether performed by Acura or Bayer. Acura agrees to use Commercially Reasonable Efforts to utilize the
Impede® Technology to obtain a formulation meeting the Target Product Profile provided there can be no assurance and Acura
makes no representation that the Impede® Technology is sufficient to obtain a formulation meeting the Target Product Profile
or that Acura will succeed in the development and Delivery of the Developed Product. Bayer will use Commercially Reasonable Efforts
to finalize development and gain Regulatory Approval in the U.S. within [*****].

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		5.2	Delivery. Acura shall use commercial reasonable efforts to Deliver a formulation and development
scale quantities of a prototype of the Developed Product meeting the Target Product Profile. “Delivery” will occur
[*****].

 

		5.3	Major Foreign Markets. Bayer shall use Commercially Reasonable Efforts to develop product
formulation(s), similar to the Developed Product, for use in the Major Foreign Markets.

 

		5.4	Joint Development Committee. The Parties shall coordinate all development activities under
a joint development committee (“DC”) which will meet to discuss progress on the Development Plan, Budget and Target
Product Profile. The parties shall establish the DC within thirty (30) days after the Effective Date. The DC will consist of equal
number of designees from each Party and meet at least quarterly in person or by teleconference during the Term. Either Party may
also call a special meeting of the DC (by videoconference or teleconference) by at least seven (7) day’s prior written notice
to the other Party, unless the other Party otherwise agrees to shorter notice, in the event such Party reasonably believes that
a significant matter must be addressed prior to the next scheduled meeting. The DC may change its size from time to time by mutual
consent of its designees, provided that the DC shall at all times consist of an equal number of designees. Each party may replace
its designees at any time upon written notice to the other Party. The DC may invite non-designees to participate in the discussions
and meetings of the DC, provided that such participants shall be approved by the other Party and have no voting authority at the
DC. A designee may designate a substitute designee if he or she cannot attend a meeting for purpose of that meeting. At each meeting
a Secretary will be appointed who shall keep minutes of the meetings, which shall be voted upon at the next meeting. One designee
of each Party shall constitute a quorum for the meetings. The DC shall act by unanimous consent, but in no event may it amend any
provisions of this Agreement. In the event of a disagreement between the Acura designees and the Bayer designees relating to a
matter within the jurisdiction of the DC, either Party may refer the matter to one designated executive of each Party, other than
a Chief Executive, for resolution (a “Senior Executive”). If such Senior Executives cannot resolve the matter within
ten (10) Business Days, then Bayer shall have final decision making authority for all DC matters other than disputes relating to:
(i) any right or obligation under this Agreement, or (ii) amendment of the Budget or the Target Product Profile or the Development
Plan that would require Acura to undertake activities not provided in the Development Plan or incur internal or external costs
not fully set forth in the Budget (regardless of whether such amounts are funded in whole or in part by Bayer). Any dispute described
in clauses (i) through (ii) above that is not resolved by Senior Executives under this Section shall be submitted for resolution
by Chief Executives and, if necessary, to binding arbitration pursuant to Section 12.1. This Section is intended to address only
disputes that arise within the specifically delineated jurisdiction of the DC and shall not affect the rights of either Party with
respect to matters outside the jurisdiction of the DC. The DC shall:

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		A.	review all material Developed Product development, manufacturing and regulatory activities, milestones
(including expected launch dates) and accomplishments on a calendar quarter basis;

 

		B.	review and upon mutual agreement, approve changes to the Development Plan, Target Product Profile
and the Budget;

 

		C.	evaluate the progress of development of the Developed Product inside and outside the United States
and the timing of launch in the United States and such other countries following receipt of Regulatory Approval in the United States
and such other countries; and

 

		D.	perform such other responsibilities as may be agreed upon by the Parties in writing from time to
time such as a joint development of a Right of First Negotiation Product.

 

		5.5	Budget and Expenses.

 

All expenses of the Parties (including
Acura’s approved out-of-pocket expenses) with respect to the DC shall be borne by Bayer. The Budget for the development of
the Developed Product (exclusive of milestones to Acura) is attached as Exhibit A. Bayer shall be responsible for [*****]
of any and all costs including without limitation the actual development and regulatory costs associated with the Developed Product.
[*****]. Notwithstanding the foregoing, nothing in this Agreement shall obligate Acura to continue development of the Developed
Product if Acura will expend more than [*****] without the express written consent of Acura [*****].

 

		5.6	Schedule of Payment.

 

		5.6.1	Within sixty (60) days of the Effective Date, Bayer shall pay Acura for all FTE Expenses and approved
out-of-pocket expenses listed on Exhibit F and incurred before the Effective Date.

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		5.6.2	Bayer shall reimburse Acura for approved out-of-pocket expenses incurred under the Development
Plan within sixty (60) days of receipt of invoice for same.

 

		5.6.3	Any FTE Expense or reimbursement for an expense or payment associated with a “Development
Event” item set forth below or incurred prior to the date set forth opposite such Development Event item shall be paid within
[*****] of Bayer’s receipt of such invoice. The Parties acknowledge that payments due relating to a Development Event may
exceed the budgeted amounts for same, as contained in the Budget or as previously approved by the DC.

 

	Development Event
	[*****]
	[*****]
	[*****]

 

		5.6.4	Any FTE Expense for a service/event not described above or contained in the Budget or previously
approved in the budget by the DC may be invoiced by Acura after incurrence of the FTE Expense and such invoice shall be paid by
Bayer within [*****] of Bayer’s receipt of such invoice.

 

		5.6.5	Notwithstanding the foregoing, on expiration or termination of the Agreement, in each case in its
entirety, Bayer shall pay all outstanding invoices from Acura within [*****] of Bayer’s receipt of such invoices and Acura
shall invoice Bayer for all unpaid FTE Expenses, unreimbursed expenses and for services performed under the Development Plan but
not paid and incurred to date and Bayer shall make payment within [*****] of Bayer’s receipt of such invoice.

 

		5.7	Cooperation for Regulatory Filings.

 

		5.7.1	Acura shall make available to Bayer all relevant Impede® Technology, Information and other
documentation relating to the Developed Products Controlled by it, including but not limited to Developed Product design history
profile, device master records, existing tool and fixture designs, component specifications and test procedures, component supplier
information, and any other data necessary or useful to support the regulatory filings to be submitted by Bayer for the Developed
Products in the Territory. From time to time during the Term, at the reasonable request of Bayer, Acura shall provide, [*****].

 

		5.7.2	Bayer shall be responsible for all required regulatory activities in the Territory. All costs related
to the regulatory activities shall be the responsibility of Bayer, except that Acura shall reasonably cooperate with Bayer to accomplish
such regulatory tasks, for which [*****].

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		5.8	Regulatory Approvals and Fees. Bayer shall be the sole owner of the Developed Product Regulatory
Approvals, registration materials, clinical documentation, and any and all country specific dossiers for [*****]. Bayer shall be
responsible for maintaining the Developed Product Regulatory Approvals and pay any and all fees and expenses in connection therewith
including, without limitation, any filing fees, establishment fees, annual product fees, active pharmaceutical supplier fees, and
any fees associated with the amendment of a Regulatory Approval, any costs and expenses associated with regulatory changes requested
by a Regulatory Authority relating to the Developed Product, or the Developed Product Regulatory Approvals.

 

ARTICLE VI–RECORDS

 

		6.1	Records. During the Term and for [*****] thereafter, each Party shall keep all usual and
proper records and books of account and all usual and proper entries relating to the Developed Product. Bayer shall maintain (electronically
or otherwise) such records and books of account containing all necessary data for the calculation of Royalty Payments and Milestone
Payments due under this Agreement.

 

		6.2	Audits. At the request and expense of either Party (“Auditing Party”), the other
Party (“Audited Party”) shall permit an independent, certified public accountant reasonably acceptable to the Audited
Party, upon giving of reasonable prior written notice of no less than [*****] and not more than once per calendar year, to examine
such records during normal working hours, as may be necessary for the sole purpose of verifying the calculation and reporting of
Net Sales, reimbursements and the accuracy of any Royalty Payment or other payment or reimbursement made under this Agreement for
any period within the preceding [*****]. All results of any such examination shall be made available to the Audited Party. In the
event that any audit reveals an under-payment in the amount of any payment obligation that should have been paid by the Audited
Party to the other, then the underpayment amount shall be paid within [*****] after the Audited Party’s receipt of Auditing
Party’s written demand therefore, plus interest thereon if such amount is in excess of [*****] unless such underpayment is
disputed by Bayer. Bayer shall have [*****] to dispute in writing such underpayment determination and if Bayer disputes such underpayment
determination, an independent, mutually agreed upon arbiter shall be selected by the Parties to resolve the dispute within [*****]
of notice of Bayer’s dispute. The cost of such arbiter shall be borne by the Party whose position is overruled by such arbiter.
Such interest shall be calculated from the date such amount was due until the date such amount is actually paid, at the rate of
[*****]. In addition, if the underpayment is in excess of [*****], then the Audited Party shall reimburse the Auditing Party for
the reasonable cost of such audit.

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

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ARTICLE VII– CONFIDENTIALITY
AND LIMITATIONS ON USE

 

		7.1	Confidential Information. During the term of this Agreement and for a period of five (5)
years thereafter, Bayer and Acura shall keep, and each shall cause its respective Affiliates, officers, directors, employees and
agents to keep, confidential all Confidential Information. The receiving Party will not disclose the Confidential Information to
any third party. The receiving Party will hold the Confidential Information secret and in confidence, and take such steps as it
normally takes to protect its own confidential and proprietary information, but in any event no less than reasonable steps, to
preserve the confidentiality of the Confidential Information. The receiving Party will use the Confidential Information solely
for the Purpose of this Agreement. The receiving Party will not use the Confidential Information for its own benefit or for the
benefit of any third party. “Confidential Information” means information that the disclosing Party considers confidential
and discloses to the receiving Party for the purpose of this Agreement. Confidential Information must be marked or otherwise identified
as confidential or proprietary or, under the circumstances surrounding the disclosure, ought in good faith to be treated as confidential
or proprietary. Confidential Information may be conveyed in written, graphical, physical or oral form. Confidential Information
may include, without limitation, information concerning the study, discovery, design, research, development, manufacture, formulation,
extraction, compounding, mixing, processing, testing, control, preservation, storage, finishing, packing, packaging, use, administration,
distribution, sale, reimbursement and/or marketing of pharmaceutical products or compounds and potential products or compounds,
data from and methodology of pre-clinical and clinical studies, the contents of any submissions to the U.S. Food and Drug Administration
(together with any successor agency), marketing plans or computer hardware and software systems and designs and plans for same.
Confidential Information may include confidential or proprietary information of a third party that is in the possession of a disclosing
Party. Confidential Information does not include information that: (a) is or hereafter becomes generally available to the public
other than by reason of any default with respect to confidentiality under this Agreement, (b) is hereafter disclosed to such Party
by a Third Party rightfully in possession of the Confidential Information and without restriction as to confidentiality or use
(and such disclosure can be properly demonstrated by the receiving Party), (c) was previously or is hereafter developed by or on
behalf of such Party, without reliance on confidential information acquired prior to the date hereof (and such can be properly
demonstrated by the receiving Party), (d) the receiving Party obtains from a third party, but only for such time that the receiving
Party reasonably believes in good faith that such information was not obtained by said third party, directly or indirectly, from
the Disclosing Party under an obligation of confidentiality; or (e) is developed by or for the receiving Party independently of
the information provided by the Disclosing Party, as evidenced by the receiving Party’s corporate records. Confidential Information
shall not be deemed to be in, or have come into, the public domain merely because any part of such Confidential Information is
embodied in general disclosures or because individual features, components or combinations thereof are or become publicly known.
Nothing in this Agreement shall prohibit a Party from disclosing Confidential Information under confidentiality provisions similar
to those in this Agreement, to Third Parties for insurance, consulting, accounting, legal, lending and borrowing, acquisition,
investment, divestment or sale and similar purposes, or to any permitted assignee of this Agreement, to the extent considered reasonably
necessary to facilitate the assignment. Nothing in this Agreement shall prohibit either Party from disclosing Confidential Information
complying with applicable legal or regulatory requirements or a validly issued subpoena, order of a court of competent jurisdiction
or other request for information from a governmental agency, seeking disclosure of any Confidential Information, provided that
such Party provides prompt notice thereof to the other Party (unless legally prohibited) so that such other Party may seek a protective
order or other appropriate remedy. Such Party shall thereafter be entitled to comply with such legal or regulatory requirements,
subpoena, court order or other request for information. The Confidential Information that is disclosed pursuant to the prior two
sentences section shall remain Confidential Information for all other purposes of this Agreement. Each of Bayer and Acura recognizes
that any violation of this confidentiality provision would cause the other irreparable harm and agrees that the other Party shall
be entitled, in addition to any other right or remedy it may have, at law or in equity, to an injunction without the posting of
any bond or other security, enjoining the disclosing Party, its Affiliates and their respective officers, directors, employees
and agents from any violation or potential violation of this Section 7.1. The terms of this Section 7.1 shall survive any termination
or expiration of this Agreement for five (5) years, except the obligations with respect to trade secrets shall survive indefinitely.
Confidential Information disclosed by an Affiliate of a Party to the other Party shall be deemed to have been disclosed by the
Party whose Affiliate disclosed such information.

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		7.2	Limitations on Use. Bayer and Acura agree that they will not use the Confidential Information
of the other Party for any purpose, other than as set forth in this Agreement and carrying out their respective obligations set
forth in this Agreement, including, without limitation, publication of any kind, without the prior written consent of such other
Party.

 

		7.3	Prior Confidentiality Agreement. Nothing herein shall relieve any Party of any breach of
that certain Confidentiality Agreement, dated as of January 21, 2014, by and between the Parties with respect to the information
disclosed between the Parties prior to the date hereof, provided any information disclosed under such agreement shall also be deemed
disclosed under this Agreement and such agreement shall not apply to any information disclosed after the date hereof, which disclosure
shall be governed by this Agreement.

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		7.4	Publicity. A Party may originate any publicity, news release and/or other public announcement,
written or oral, relating to the existence or terms of this Agreement or referencing the other party’s name, trademarks,
trade name or logos (a “Public Disclosure”) that is required by Applicable Law, stock exchange and/or regulatory authority
(a “Required Public Disclosure”). In the event of any Required Public Disclosure, the disclosing party shall endeavor,
on a reasonable basis under the circumstances, to provide a meaningful opportunity for the other party to review and comment upon
such Required Public Disclosure before disclosure to the public and shall give reasonable consideration to all reasonable additions,
deletions or changes suggested thereto including whether the disclosure is in fact a Required Disclosure. The review and/or comment
by a Party on any Required Public Disclosure to be made by the other Party shall not constitute or be deemed confirmation by the
reviewing Party of the accuracy of such disclosure, and the originating Party shall solely be responsible for its contents. Mutual
consent of the Parties shall be discussed and obtained prior to a Party originating any Public Disclosure that is not a Required
Public Disclosure. The contents of any Required Public Disclosure, or Public Disclosure mutually consented to by the Parties, previously
released pursuant to this Section 7.4 can be subsequently verbally disclosed only by either Party without the other Party’s
approval, provided that each Party shall keep the other Party reasonably informed about their plans for such verbal disclosure.

 

		7.5	Contacts and Statements. Contacts with the applicable governmental agency with respect to
this Agreement shall be coordinated between Acura and Bayer. The Parties shall mutually agree to the responsible Party for initiating
such contact. All public statements regarding Bayer trademarks will be the responsibility solely of Bayer. Where practical, all
such statements will be provided to Acura for content review prior to release.

 

ARTICLE XIII– LIABILITY
AND INDEMNIFICATION

 

		8.1	Maximum Liability. Other than a Party’s indemnification obligations (except for [*****]
or breach of the confidentiality provisions, each Party’s maximum liability to the other Party for any claim arising from
this Agreement for any reason whatsoever (excluding monetary consideration for this Agreement, such as such as Milestone Payments,
Royalty Payments, reimbursements for FTE Expenses and out-of-pocket costs and expenses) will not exceed [*****]

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

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		8.2	Consequential Damages. Except for breaches of the confidentiality provisions, under no circumstances
whatsoever will either Party be liable to the other in contract, tort, negligence, breach of statutory duty, or otherwise for (i)
any (direct or indirect) loss of profits, of production, of anticipated savings, of business, or goodwill or (ii) for any other
liability, damage, costs, or expense of any kind incurred by the other Party of an indirect or consequential nature, regardless
of any notice of the possibility of these damages.

 

		8.3	Indemnification by Acura. Acura shall indemnify, defend and hold Bayer, its officers, employees
and its Affiliates harmless from and against all liabilities, claims, demands, damages, costs, expenses or money judgments (including
reasonable attorneys’ fees) incurred by or rendered against Bayer, its officers and employees or its Affiliates for personal
injury, sickness, disease or death or other damages which arise out of (a) Acura’s development of the Developed Product pursuant
to the Development Plan (limited to those subjects included in the clinical studies conducted by Acura); (b) Acura’s breach
of any of its obligations under this Agreement; (c) the gross negligence or intentional misconduct of Acura; or (d) Acura’s
breach of any representation or warranty made or given in this Agreement.

 

		8.4	Indemnification by Bayer. Bayer shall indemnify, defend and hold Acura, its officers, employees
and its Affiliates harmless from and against all liabilities, claims, demands, damages, costs, expenses or money judgments (including
reasonable attorneys’ fees) incurred by or rendered against Acura, its officers and employees or its Affiliates for personal
injury, sickness, disease or death or other damages which arise out of: (a) Bayer’s breach of any of its obligations under
this Agreement; (b) any claims arising out of the development (exclusive of the claims described in Section 8.3(b) above), manufacturing,
or commercialization of the Developed Product; (c) the gross negligence or intentional misconduct of Bayer; (d) Bayer’s breach
of any representation or warranty made or given by Bayer in this Agreement; or (e) any actual or alleged infringement of any Third
Party patent, copyright, trademark or trade dress rights arising from materials, labeling, marketing or advertising of the Developed
Product.

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		8.5	Procedure; Defense.

 

		8.5.1	Each party claiming indemnification must promptly notify the other Party in writing, providing
reasonable detail, of any claim upon receipt of notice thereof; provided, however, that failure to given such notice shall not
affect the indemnification provided under this Agreement except to the extent the indemnifying Party shall have been actually prejudiced
as a result of such failure.

 

		8.5.2	The following provisions shall apply to any Third Party claim for which a Party is entitled to
indemnification from the other Party under this Article 8. If the indemnifying Party elects to defend or, if local procedural rules
or laws do not permit the same, elects to control the defense of a Third Party claim, it shall be entitled to do so provided it
gives notice to the indemnified Party of its intention to do so within [*****] after the receipt of the written notice from the
indemnified Party of the potentially indemnifiable Third Party Claim (the “Litigation Condition”). Subject to compliance
with the Litigation Condition, the indemnifying Party shall retain counsel reasonably acceptable to the indemnified Party (such
acceptance not to be unreasonably withheld or delayed) to represent the indemnified Party and shall pay the fees and expenses of
such counsel related to such proceeding. In any such proceeding, the indemnified Party shall have the right to retain its own counsel,
but the fees and expenses of such counsel shall be at the expense of the indemnified Party. The indemnified Party shall not settle
any claim for which it is seeking indemnification without the prior consent of the indemnifying Party which consent shall not be
unreasonably withheld, conditioned or delayed. The indemnified Party shall, if requested by the indemnifying Party, cooperate in
all reasonable respects in the defense of such claim that is being managed and/or controlled by the indemnifying Party, at the
indemnifying Party’s cost and expense. The indemnifying Party shall not, without the written consent of the indemnified Party
(which consent shall not be unreasonably withheld, conditioned or delayed), effect any settlement of any pending or threatened
proceeding in which the indemnified Party is, or based on the same set of facts could have been, a party and indemnity could have
been sought hereunder by the indemnified Party, unless such settlement includes an unconditional release of the indemnified Party
from all liability on claims that are the subject matter of such proceeding and will not result in the Indemnified Party’s
becoming subject to injunctive or other relief or otherwise adversely affect the business of the indemnified Party in any manner.
Notwithstanding the foregoing, a Party’s consent (which shall not be unreasonably withheld, delayed or conditioned) shall
be required for any settlement that entails any license, covenant not to sue relating to, admission of invalidity or unenforceability
or abandonment of any of its intellectual property. If the Litigation Condition is not met, then the indemnified Party shall have
the right to control the defense of such Third Party Claim, for which the indemnifying Party shall pay the reasonable fees and
costs incurred by the indemnified Party, and the Parties shall cooperate in and be consulted on the material aspects of such defense
at the indemnifying Party’s expense.

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

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ARTICLE
IX– NOTICES

 

		9.1	Notices. Any notice or request to be given or furnished under this Agreement by any Party
to the other shall be in writing and shall be delivered personally or registered or certified mail, postage prepaid, or by overnight
delivery service to the following:

 

		TO
                          ACURA:	Acura
                                         Pharmaceuticals, Inc.

			616 N. North Court

			Palatine, IL 60067

			Attn: Robert B. Jones

			Telephone No. [*****]

 

		Copy
                          To:	LeClairRyan

			1037 Raymond Blvd.

			Newark, NJ 07102

			Attn: John P. Reilly, Esq.

			Telephone No. [*****]

			

 

With a copy
to the Attention of the Legal Department at the same address.

 

			

		TO
                           BAYER:	Bayer
                                         HealthCare LLC

			100 Bayer Blvd.

			Whippany, NJ 07981

			Attention: Business Development Department

			Telephone No.: [*****]

 

With a copy
to the Attention of the Legal Department at the same address.

 

		9.2	Receipt of Notice.All notices and other communications
given to any Party in accordance with the provisions of this Agreement shall be deemed to have been given on the date of receipt
if delivered by hand or overnight courier services or sent by telecopy, or on the date five (5) business days after dispatch by
certified or registered mail (postage prepaid) if mailed, in each case delivered, sent or mailed (properly addressed) to such
Party as provided in this Article IX, or in accordance with the latest unrevoked direction from such Party given in accordance
with this Article IX.

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

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ARTICLE X-
PATENT PROSECUTION, INFRINGEMENT

 

		10.1	Ownership of Intellectual Property Rights. Except as otherwise provided in Section 5.8,
Acura shall own [*****]. Bayer owns [*****]. Acura hereby licenses to Bayer, on a non-exclusive basis, the use of the mark Impede®
in the Field and Territory solely for the commercialization of the Developed Product during the Term.

 

		10.2	Patent Prosecution and Maintenance. Acura is responsible for the prosecution and maintenance
of the Impede® Patent Rights in its sole discretion and at its own cost and expense. Acura shall provide Bayer a reasonable
opportunity to review and comment on such prosecution and maintenance efforts regarding Impede® Patent Rights in the Territory
that may claim the Developed Product, or the making or the use thereof. Acura shall provide Bayer with a copy of material communications
from any patent authority in the Territory regarding such Impede® Patent Rights within a reasonable time after receipt of such
communications and shall provide drafts of any material filings or responses to be made to such patent authorities in a reasonable
amount of time in advance of submitting such filings or responses for Bayer’s review and comment. Acura shall reasonably
consider such comments by Bayer in connection with the prosecution and maintenance of the Impede® Patent Rights. If Acura decides
to cease the prosecution or maintenance of any Impede® Patent Rights that claim the Developed Product, after it has commenced
prosecution of such Impede Patent Rights in the Territory, Acura shall notify Bayer in writing at least sixty (60) days prior to
any relevant deadline so that Bayer may, at its discretion, assume the responsibility for the prosecution or maintenance of such
Impede® Patent Rights in the Territory. Bayer shall have forty (40) days to decide whether or not to assume these costs, during
which time Acura shall make Commercially Reasonable Efforts to prepare, prosecute, and maintain any such Impede® Patent Rights.
In the event Bayer chooses to maintain such preparation and prosecution or pay such maintenance fees (to the extent it is not already
required to pay such fees), Acura agrees to cooperate with Bayer to execute all lawful papers and instruments reasonably necessary
to transfer and assign such Impede® Patent Rights to Bayer, at Bayer’s sole expense, provided Bayer shall grant Acura
an exclusive, perpetual, sub licensable, royalty free license to such Impede Patent Rights other than with respect to the Developed
Product.

 

		10.3	Infringement of Impede® Patent Rights. Each of Bayer and Acura will notify the
other Party within [*****] upon learning of any possible infringement by a Third Party of the Impede® Patent Rights,
which infringement may reasonably be expected to affect the commercialization of the Developed Product. [*****][two pages redacted].

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		10.7	Allegations of Infringement by Third Parties. [*****][one page redacted].

 

		10.8	Settlement of Allegations of Infringement. [*****].

 

ARTICLE XI-WARRANTIES

 

		11.1	Mutual Representations, Warranties and Covenants. Each Party represents and warrants that
(i) it has the full right, power and authority to enter into this Agreement; (ii) that entering into and performing its obligations
set forth in this Agreement does not conflict with any other agreement to which it is a party; and (iii) as at the Effective Date,
there are no claims, judgments, litigations, suits, actions, disputes, arbitration, judicial or legal, administrative or other
proceedings or governmental investigations pending or, to such Party’s knowledge, threatened against such Party or any of
its Affiliates, and neither such Party nor its Affiliates is a party to any settlement agreement, which would be reasonably expected
to materially affect or restrict the ability of such Party to consummate the transactions contemplated under this Agreement and
to perform its obligations under this Agreement.

 

		11.2	Acura Representations, Warranties and Covenants. Acura represents and warrants that: [*****].

 

		11.3	Bayer’s Representations Warranties and Covenants. Bayer represents, warrants and covenants
that (i) it shall develop, manufacture, commercialize the Developed Product in accordance with Applicable Law; and (ii) it believes
the amounts in the Budget (other than those to be paid to Acura) are reasonable amounts to complete development and receipt of
U.S. Regulatory Approval of the Developed Product. [*****].

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

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ARTICLE XII– MISCELLANEOUS

 

		12.1	Dispute Resolution. Bayer and Acura agree to use
good faith efforts to resolve any and all disputes arising out of or relating to this Agreement. If after [*****], the Parties
are unable to resolve the dispute, then the matter shall by fully and finally resolved by arbitration. A Party that desires to
arbitrate a dispute shall serve a written notice upon another requesting arbitration of a dispute pursuant to this Section 12.1.
Any such arbitration shall be submitted to final and binding arbitration under the then current commercial arbitration rules of
the American Arbitration Association (the “AAA”) in accordance with this Section 12.1. The place of arbitration
of any dispute shall be New York, New York. Such arbitration shall be conducted by one (1) arbitrator mutually agreed by the Parties
but if such agreement cannot be reached within [*****] of the commencement of the arbitration, then an arbitrator appointed by
the AAA. The arbitrator shall be a person with relevant experience in the pharmaceutical industry. The arbitration proceeding
shall be held as soon as practicable but in any event within [*****] of appointment of the arbitrator. Any award rendered by the
arbitrators shall be final and binding upon the Parties. Judgment upon any award rendered may be entered in any court having jurisdiction,
or application may be made to such court for a judicial acceptance of the award and an order of enforcement, as the case may be.
The arbitrator shall render a formal, binding, non-appealable resolution and award as expeditiously as possible, but not more
than [*****] after the hearing. Each Party shall pay its own expenses of arbitration, and the expenses of the arbitrator shall
be equally shared between the Parties unless the arbitrators assess as part of their award all or any part of the arbitration
expenses of a Party (including reasonable attorneys’ fees) against the other Party. A Party may make application to the
Arbitrator for the award and recovery of its fees and expenses (including reasonable attorneys’ fees). This Section 12.1,
shall not prohibit a Party from seeking injunctive relief from a court of competent jurisdiction in the event of a breach or prospective
breach of this Agreement by any other Party which would cause irreparable harm to the first Party.

 

		12.2	Waivers; Amendment. The failure of either Party to insist, in any one or more instances,
upon the performance of any of the terms, covenants or conditions of this Agreement or to exercise any right hereunder, shall not
be construed as a waiver or relinquishment of the future performance of any such term, covenant or conditions or the future exercise
of such right, and the obligation of the other Party with respect to such future performance shall continue in full force and effect.
No item or provision of this Agreement may be altered, amended or waived except by a writing signed by both Parties.

 

		12.3	Assignment and Sub-License. Neither Party shall
sub-license any of its rights or obligations under this Agreement, in whole or in part to any person, firm, partnership, or other
entity, except to an Affiliate, without the prior written consent of the other Party, which consent shall not be unreasonably
withheld, delayed or conditioned. Notwithstanding the foregoing, a Party may assign this Agreement in connection with (i) the
transfer of all or substantially all of its assets or its Impede Technology assets (by merger, sale of assets or otherwise) to
the transferee thereof or (ii) the sale of its line of business to which this Agreement relates, provided however, that Acura
will cause the acquirer to confirm with Bayer prior to closing such transaction that Bayer has such licenses to and a non-compete
with respect to the Developed Product as are provided herein. Notwithstanding the foregoing, nothing shall prevent Bayer from
offering to acquire the Developed Product intellectual property from Acura on terms negotiated between the parties.

 

*****Confidential treatment requested pursuant to a request for confidential treatment
filed with the Securities and Exchange Commission; omitted portions have been separately filed with the Commission.

 

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		12.4	Other Terms and Conditions. Other terms and conditions not inconsistent with terms and conditions
in this Agreement covering Developed Product(s) to be supplied under this Agreement will be provided in purchase orders and releases
issued by Bayer and in order acknowledgments and invoices issued by Acura. In the event of any conflict of terms in these documents,
Bayer and Acura agree to negotiate in good faith to resolve such differences, unless such terms conflict with the terms of this
Agreement, in which case the terms of this Agreement shall control.

 

		12.5	Covenant of Further Assurances. Bayer and Acura covenant and agree that subsequent to the
execution and delivery of this Agreement and without any additional consideration, each of Bayer and Acura shall execute and deliver
any further legal instruments and perform such acts which are or may become necessary to effectuate the purposes of this Agreement.

 

		12.6	Headings. The heading of the Articles and Sections used in this Agreement are included for
convenience only and are not to be used in construing or interpreting this Agreement.

 

		12.7	Governing Law. Unless any competent governmental entity or any other applicable laws and
regulations require otherwise, this Agreement shall be governed by and construed under the laws of the State of New Jersey as applied
to agreements executed and performed solely in New Jersey, without regard to choice-of-law principles thereof.

 

		12.8	Subcontracting. Acura shall not subcontract its obligations hereunder to subcontractors
(other than Affiliates) without the prior written consent of Bayer, which shall not be unreasonably withheld, provided however
that without such consent Acura may use third party contract research organizations and other service and material providers, as
long as Acura actively oversees the project.

 

		12.9	Relationship. Acura is an independent contractor engaged by Bayer for the provision of the
Developed Product(s). Nothing in this Agreement shall constitute either Party as an employee, agent or general representative of
the other, nor shall either Bayer or Acura have the right or authority to assume, create or incur any liability or any obligation
of any kind, express or implied, against, or in the name of or on behalf of, the other.

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

     25

     

    

  

EXECUTION COPY

 

		12.10	Severability. The provisions of this Agreement shall be deemed separate. Accordingly, the
invalidity or unenforceability of any particular provision of this Agreement shall not affect the other provisions, and this Agreement
shall be construed in all respects as if such invalid or unenforceable provision were omitted, except in cases where such unenforceable
provision is a basic prerequisite of any Party or both Parties to enter into this Agreement. The Parties shall in such an instance
use their best efforts to replace the unenforceable provision(s) with valid, legal and enforceable provision(s) which, insofar
as practical, implement the purposes of this Agreement.

 

		12.11	Entire Agreement. This Agreement including all Exhibits and Schedules attached hereto constitutes
the entire Agreement between Bayer and Acura with respect to the subject matter addressed herein and this Agreement supersedes
all prior understandings and agreements, whether oral or written, between the Bayer and Acura with respect thereto. Any amendment
to any provisions set forth in the Agreement must be in writing, signed by both Bayer and Acura and specifically state that it
is an amendment.

 

		12.12	Counterparts; Facsimile Signatures. This Agreement may be executed in multiple counterparts,
each of which shall be deemed to be an original and of equal force and effect, but all of which taken together shall constitute
one and the same instrument. A facsimile, digital, PDF, e-mail or other electronic copy hereof shall suffice as an original Agreement.

 

		12.13	Waiver of Rule of Construction. Each Party has had the opportunity to consult with counsel
in connection with the review, drafting and negotiation of this Agreement. Accordingly, the rule of construction that any ambiguity
in this Agreement shall be construed against the drafting Party shall not apply.

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

     26

     

    

  

EXECUTION COPY

 

IN WITNESS
WHEREOF, Bayer and Acura have caused this Agreement to be executed by their duly authorized officers as of the day and year
first above written.

  

	ACURA PHARMACEUTICALS, INC.	 	BAYER HEALTHCARE LLC
	 	 	 	 	 
	By:	/s/ Robert B. Jones	 	By:	/s/ Mike DiBiasi
	 	 	 	 	 
	Name:	 Robert B. Jones	 	Name:	Mike DiBiasi
	 	 	 	 	 
	Title:	President & CEO	 	Title:	V.P. Allergy
	 	 	 	 	 
	Date:	June 15, 2015	 	Date:	June 5, 2015

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

     27

     

    

 

EXECUTION COPY

 

EXHIBIT
A

 

 

Development
Plan

 

[*****][table
redacted]

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

     28

     

    

  

EXECUTION COPY

 

Exhibit
B

 

 

BAYER budget and timeline
for Delivery of the Prototype [*****].

 

*****Confidential treatment
requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted portions
have been separately filed with the Commission.

 

     29

     

    

  

EXECUTION COPY

 

	[*****] – Budget	 
	 	 	 
	[*****][1.1 pages redacted]	 	 

 

*****Confidential treatment
requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted portions
have been separately filed with the Commission.

 

     30

     

    

 

Exhibit
C 

Impede®
Patent Rights

ISSUED
OR NOTICE OF ALLOWANCE

 

[*****][1.25
pages redacted]

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

     

     

    

 

EXHIBIT
D

 

Target
Product Profile

Including
Success Criteria for 

Pilot
Bioequivalence Study

 

The following
constitutes the Target Product Profile [*****]

 

Pilot Bioequivalence Study Requirements:

 

[*****]

 

*****Confidential treatment
requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted portions
have been separately filed with the Commission.

 

     

     

    

 

Exhibit
E

 

Form
of Royalty Report.

 

	ROYALTY REPORT
	Contract Year Ended ______________
	Quarter Reported _________________

 

	Licensee Name:	 
	Property:	 
	Territory:	 
	Address:	 
	Contact:  	 
	Phone Number:	 
	Fax Number:  	 

 

[*****][1.1 pages redacted]

 

*****Confidential
treatment requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted
portions have been separately filed with the Commission.

 

     

     

    

 

 

Exhibit
F

 

Pre-Effective
Date Amounts to be Reimbursed to Acura

 

	Item	Quantity	Amount
	[*****]	[*****]	[*****]
	[*****]	[*****]	[*****]
	  Total	 	[*****]

 

*****Confidential treatment
requested pursuant to a request for confidential treatment filed with the Securities and Exchange Commission; omitted portions
have been separately filed with the Commission.Exhibit

Exhibit 4.1
Execution Version

THIS INSTRUMENT OF RESIGNATION, APPOINTMENT AND ACCEPTANCE (this “Instrument”), dated as of February 10, 2016 (the close of business on such date, the “Effective Date”), is by and among Horsehead Holding Corp., a Delaware corporation (the “Issuer”), Delaware Trust Company, a Delaware state chartered trust company (the “Successor Trustee”), and U.S. Bank National Association, a national banking association duly organized and existing under the laws of the United States of America (the “Resigning Trustee”). Capitalized terms not otherwise defined herein shall have the same meaning ascribed to such terms in the Indenture (as defined below).

RECITALS

WHEREAS, pursuant to an Indenture dated as of July 27, 2011 (as the same may be supplemented and amended from time to time, the “Indenture”), entered into by the Issuer and the Resigning Trustee, the Issuer issued 3.80% Convertible Senior Notes due 2017 (the “Notes”);

WHEREAS, the Issuer appointed the Resigning Trustee as the Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture;

WHEREAS, there is presently issued and outstanding $100,000,000 in aggregate principal amount of Notes;

WHEREAS, Section 10.09 of the Indenture provides that the Trustee may at any time resign by giving written notice of such resignation to the Issuer and such resignation shall become effective upon a successor trustee’s acceptance of appointment by the Issuer as provided thereunder;

WHEREAS, Section 10.10 of the Indenture provides that any successor Trustee appointed as provided in Section 10.09 of the Indenture shall execute, acknowledge and deliver to the Issuer and to its predecessor Trustee an instrument accepting such appointment thereunder;

WHEREAS, the Resigning Trustee desires to resign as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture, and the Issuer desires to appoint the Successor Trustee as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture to succeed the Resigning Trustee in each of such capacities under the Indenture; and

WHEREAS, the Successor Trustee is willing to accept the appointment as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture;

NOW, THEREFORE, in consideration of the covenants herein and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1

1.Acceptance of Resignation of Resigning Trustee; Appointment of Successor Trustee.  The Resigning Trustee hereby resigns as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture effective as of the Effective Date. 

The Issuer accepts the resignation of the Resigning Trustee as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar, and pursuant to Section 10.09 of the Indenture hereby appoints the Successor Trustee as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture. The Issuer hereby acknowledges that, as of the Effective Date, the Successor Trustee shall be the Trustee under the Indenture and shall hold all rights, powers, trusts, privileges, duties and obligations which the Resigning Trustee now holds under and by virtue of the Indenture. The Issuer agrees that the Successor Trustee shall be entitled to charge fees for the Successor Trustee’s services in accordance with the fee schedule submitted contemporaneously herewith to the Issuer by the Successor Trustee.

2.    Issuer Representations and Warranties.  The Issuer represents and warrants to the Successor Trustee that:

a.    It is a corporation duly organized and validly existing pursuant to the laws of the State of Delaware;

b.    It has duly authorized the execution and delivery of this Instrument;

c.    The Indenture was validly and lawfully executed and delivered by the Issuer and is in full force and effect; and

d.    Assuming the accuracy of the representations and warranties made by the Resigning Trustee in Section 3 hereof, all conditions precedent relating to the appointment of the Successor Trustee as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture have been complied with by the Issuer.

3.    Resigning Trustee Representations and Warranties.  The Resigning Trustee hereby represents and warrants to the Successor Trustee that:

a.    No covenant or condition contained in the Indenture has been waived by the Resigning Trustee or, to the knowledge of the responsible officer of the Resigning Trustee who is signing this document, by the Holders of the percentage in aggregate principal amount of Notes required by the Indenture to effect any such waiver; 
    
b.    There is no action, suit or proceeding pending or, to the knowledge of the responsible officer of the Resigning Trustee who is signing this document, threatened against the Resigning Trustee before any court or governmental authority arising out o

2

f any action or omission by the Resigning Trustee as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar;

c.    The Resigning Trustee shall endeavor to deliver to the Successor Trustee, as of or immediately after the Effective Date hereof, to the extent available, all of the documents listed in Exhibit C hereto;  

d.    The execution and delivery of this Instrument has been duly authorized by the Resigning Trustee, and this Instrument constitutes the Resigning Trustee’s legal, valid, binding and enforceable obligation in accordance with its terms;

e.    As of the Effective Date, the Resigning Trustee will hold no property under the Indenture;

f.    To the best knowledge of the responsible officer of the Resigning Trustee who is signing this document, the Resigning Trustee has lawfully discharged its duties as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture; 

g.    Each person who so authenticated the Notes was duly elected, qualified and acting as an officer or authorized signatory of the Resigning Trustee and empowered to authenticate the Notes at the respective times of such authentication and the signature of such person or persons appearing on such Notes is each such person’s genuine signature;

h.    The Resigning Trustee certifies that $100,000,000 in aggregate principal amount of Notes is outstanding and interest is current through July 1, 2015; and

i.    Except as set forth on Exhibit C hereto, the Indenture has not been supplemented and remains in full force and effect.

4.    Successor Trustee Representation and Warranty.  The Successor Trustee represents and warrants to the Resigning Trustee and the Issuer that:

a.    It is eligible to serve as Trustee under Section 10.08 of the Indenture; and

b.    The execution and delivery of this Instrument has been duly authorized by the Successor Trustee, and this Instrument constitutes the Successor Trustee’s legal, valid, binding and enforceable obligation in accordance with its terms.

5.    Assignment etc. by Resigning Trustee.  Effective on the Effective Date, the Resigning Trustee hereby confirms, assigns, transfers, delivers and conveys to the Successor Trustee, as Trustee under the Indenture, upon the trusts expressed in the Indenture, all rights, powers, trusts, privileges, duties and obligations which the Resigning Trustee now holds under and by virtue of the Indenture, and effective as of such date does hereby pay over to 

3

the Successor Trustee any and all property and money, if any, held by the Resigning Trustee under and by virtue of the Indenture, with like effect as if the Successor Trustee was originally named as Trustee under the Indenture. Promptly after the execution and delivery of this Instrument, the Resigning Trustee shall cause a notice, the form of which is annexed hereto as Exhibit A to be sent to each Holder of the Notes.
6.    Acceptance by Successor Trustee. Pursuant to Section 10.10 of the Indenture, the Successor Trustee hereby accepts its appointment as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture, and this Instrument and the resignation, appointment and acceptance effected hereby shall be effective as of the Effective Date; provided, that the resignation of the Resigning Trustee as Paying Agent and the appointment of the Successor Trustee as Paying Agent under the Indenture shall be effective 10 business days after the Effective Date. The Successor Trustee will perform said rights, powers and duties upon the terms and conditions set forth in the Indenture. Promptly after the execution and delivery of this Instrument, the Successor Trustee shall cause a notice, the form of which is annexed hereto as Exhibit B to be sent to each Holder of the Notes.
7.    Additional Documentation.  The Resigning Trustee, for the purposes of more fully and certainly vesting in and confirming to the Successor Trustee the rights, powers, trusts, privileges, duties and obligations hereby assigned, transferred, delivered and conveyed, agrees, upon reasonable request of the Successor Trustee, to execute, acknowledge and deliver such further instruments of conveyance and further assurance and to do such other things as may reasonably be required by the Successor Trustee.

8.    Choice of Laws.  This Instrument shall be governed by the laws of the State of New York.  

9.    Counterparts.  This Instrument may be executed in any number of counterparts, each of which, when so executed and delivered, shall be an original, but all counterparts shall constitute but one and the same instrument.

10.    Survival of Issuer’s Obligations to Resigning Trustee. Notwithstanding the resignation of the Resigning Trustee as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture, the Issuer shall remain obligated under Section 10.06 of the Indenture to compensate, reimburse and indemnify the Resigning Trustee in connection with its prior service as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar as provided in the Indenture, and nothing contained in this Instrument shall in any way abrogate the obligations of the Issuer to the Resigning Trustee under the Indenture or any lien created in favor of the Resigning Trustee thereunder.  

11.    Notices.  All notices, whether faxed or mailed, will be deemed received in accordance with Section 1.05 of the Indenture to the following:

4

TO THE SUCCESSOR TRUSTEE:

Delaware Trust Company
2711 Centerville Road 
Wilmington, DE 19808 
Attn: Trust Administration
Facsimile:  (302) 636-8666 

With a copy to:

Golenbock Eiseman Assor Bell & Peskoe LLP
437 Madison Avenue 
New York, NY 10022
Attn: Jonathan L. Flaxer and Marc D. Rosenberg

TO THE RESIGNING TRUSTEE:

U.S. Bank National Association 
    333 Commerce Street, Suite 800 
    Nashville, Tennessee 37201
Attn: Corporate Trust Services

With a copy to:

Waller Lansden Dortch & Davis, LLP
Nashville City Center
511 Union Street, Suite 2700
Nashville, Tennessee 37219
Facsimile: (615) 244-6804
Attention: Beth E. Vessel
    
THE ISSUER:

Horsehead Holding Corp.
4955 Steubenville Pike, Suite 405
Pittsburgh, Pennsylvania 15205
Facsimile: (412) 788-1812
Attention: Gary R. Whitaker, Esq.
Vice President, General Counsel and Secretary

With a copy to:

5

Kirkland & Ellis LLP
300 N LaSalle
Chicago, Illinois 60654
Facsimile: (312) 862-2200
Attention: James S. Rowe, Esq.    
    
12.    Successors and Assigns.  All agreements of the Issuer, the Resigning Trustee and the Successor Trustee in this Instrument shall bind their respective successors and assigns.

[Remainder of page left intentionally blank.]

6

IN WITNESS WHEREOF, the parties hereto have executed this Instrument as of the date set forth above.

Horsehead Holding Corp., as Issuer

By__/s/ Robert D. Scherich_______________
Name:    Robert D. Scherich
   Its:    Vice President and Chief Financial Officer

U.S. Bank National Association, as Resigning Trustee

By__/s/ Wally Jones ____________________
Name: Wally Jones
   Its:     Vice President

Delaware Trust Company, as Successor Trustee

By__/s/ Alan R. Halpern__________________    
Name:    Alan R. Halpern
   Its:    Vice President

7

EXHIBIT A

[U.S. Bank National Association Letterhead]

Notice to Holders of 3.80% Convertible Senior Notes due 2017 (the “Notes”)
issued pursuant to that certain indenture between Horsehead Holding Corp.
and U.S. Bank National Association (the “Trustee”), dated July 27, 2011

CUSIP NO: 440694AB3

NOTE:  THIS NOTICE CONTAINS IMPORTANT INFORMATION.  IF APPLICABLE, ALL DEPOSITORIES, CUSTODIANS, AND OTHER INTERMEDIARIES RECEIVING THIS NOTICE ARE REQUESTED TO EXPEDITE RE-TRANSMITTAL TO BENEFICIAL OWNERS OF THE NOTES REFERENCED ABOVE IN A TIMELY MANNER.

The Trustee hereby notifies you of its resignation as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar under the Indenture, pursuant to which the Notes were issued and are outstanding.

The Trustee’s resignation as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar was effective as of the close of business on February ____, 2016.

Dated:  February ____, 2016

                
U.S. Bank National Association
                

EXHIBIT B

[Delaware Trust Company Company Letterhead]

Notice to Holders of Horsehead Holding Corp. (the “Issuer”)
3.80% Convertible Senior Notes due 2017 (the “Notes”)

CUSIP NO: 440694 AB3

NOTE:  THIS NOTICE CONTAINS IMPORTANT INFORMATION.  IF APPLICABLE, ALL DEPOSITORIES, CUSTODIANS, AND OTHER INTERMEDIARIES RECEIVING THIS NOTICE ARE REQUESTED TO EXPEDITE RE-TRANSMITTAL TO BENEFICIAL OWNERS OF THE NOTES REFERENCED ABOVE IN A TIMELY MANNER.

We hereby notify you of the resignation of U.S. Bank National Association, as Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar of the Notes (the “Resigning Trustee”) under the Indenture, dated as of July 27, 2011 (the “Indenture”), between the Issuer and the Resigning Trustee, pursuant to which the Notes were issued and are outstanding.

The Issuer has appointed Delaware Trust Company (the “Successor Trustee”), a Delaware state chartered trust company, whose Corporate Trust Office is located at 2711 Centerville Road, Wilmington, DE 19808, as successor Trustee, Paying Agent, Custodian, Conversion Agent, Bid Solicitation Agent and Registrar of the Notes under the Indenture, which appointment has been accepted and became effective at the close of business on the date hereof. Delaware Trust Company has also been appointed as the office or agency where the Notes may be surrendered for registration of transfer or exchange, where the Notes may be presented or surrendered for payment and where notices and demands to or upon the Issuer in respect of the Notes and the Indenture may be served.

Dated:  February ____, 2016

Delaware Trust Company, as Successor Trustee
                

EXHIBIT C

Documents to be delivered by Resigning Trustee to Successor Trustee as to the Indenture:
1.Executed copy of the Indenture and Supplemental Indentures, if any.
		
	2.
	Copy of the most recent Compliance Certificate delivered pursuant to the Indenture.

		
	3.
	Certified list of the Holders of Notes as of the Effective Date, certificate detail and all “stop transfers” and the reason for such “stop transfers” (or, alternatively, if there are a substantial number of registered Holders of Notes, the computer tape reflecting the identity of such Holders of Notes), and copies of other documents and information relating to administration and status of the trust created by the Indenture.

		
	4.
	Copies of any official notices sent by the Trustee to all Holders of Notes pursuant    to the terms of the Indenture during the past twelve months.

		
	5.
	Notes debt service records.

		
	6.
	Trust account statements for one-year period preceding the Effective Date of this Instrument.

		
	7.
	All unissued Note inventory, if any and DTC FAST held global certificates.

		
	8.
	Such other non-confidential, unprivileged documents or information as the                  Successor Trustee may request on or after the Effective Date.

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