Signature Page to Securities Purchase Agreement] REGISTRATION RIGHTS AGREEMENT This Registration Rights Agreement (this “Agreement”) is made and entered into as of [], 2024, by and between Arrowhead Pharmaceuticals, Inc., a Delaware corporation (the...

[Signature Page to Securities Purchase Agreement] REGISTRATION RIGHTS AGREEMENT This Registration Rights Agreement (this “Agreement”) is made and entered into as of [], 2024, by and between Arrowhead Pharmaceuticals, Inc., a Delaware corporation (the “Company”), and Avoro Life Sciences Fund LLC, a Delaware limited liability company (the “Purchaser”). NOW, THEREFORE, IN CONSIDERATION of the mutual covenants contained in this Agreement, and for other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, the Company and the Purchaser agree as follows: ARTICLE I DEFINITIONS Section 1.1. Definitions. As used in this Agreement, the following terms shall have the following meanings: (a) “Adverse Disclosure” means public disclosure of material non-public information that, in the good faith judgment of the board of directors of the Company: (i) would be required to be made in such Registration Statement filed with the SEC by the Company so that such Registration Statement, from and after its effective date, does not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; (ii) would not be required to be made at such time but for the filing, effectiveness or continued use of such Registration Statement; and (iii) the Company has a bona fide business purpose for not disclosing publicly. (b) “Affiliate” means, with respect to any Person, another Person that controls, is controlled by or is under common control with such Person; provided, that with respect to the Purchaser, the term “Affiliate” shall not include any employee benefit plan of Purchaser. A Person shall be deemed to control another Person if such Person possesses, directly or indirectly, the power to direct or cause the direction of the management and policies of such Person, whether through the ownership of voting securities, by contract or otherwise. For the purposes of this Agreement, in no event shall the Purchaser or any of its Affiliates be deemed Affiliates of the Company or any of its Affiliates, nor shall the Company or any of its Affiliates be deemed Affiliates of the Purchaser or any of its Affiliates. (c) “Agreement” has the meaning set forth in the preamble. (d) “Business Day” means any day except Saturday, Sunday and any legal holiday or a day on which banking institutions in Pasadena, California generally are authorized or required by law or other governmental actions to close. (e) “Closing” means the date of the purchase and sale of the Shares and the Pre-Funded Warrant pursuant to the Purchase Agreement. (f) “Common Stock” means the common stock of the Company, par value $0.001 per share.

(g) “Company Indemnitee” has the meaning set forth in Section 2.8. (h) “Effectiveness Period” has the meaning set forth in Section 2.1.3. (i) “Exchange Act” means the Securities Exchange Act of 1934, as amended, as in effect from time to time. (j) “Filing Deadline” has the meaning set forth in Section 2.1.1. (k) “FINRA” means the Financial Industry Regulatory Authority. (l) “Holder” or “Holders” means the Purchaser, or such other holder or holders, as the case may be, from time to time of Registrable Securities. (m) “Initial Registration Statement” has the meaning set forth in Section 2.1.1(a). (n) “Issuer Free Writing Prospectus” means an issuer free writing prospectus, as defined in Rule 433 under the Securities Act, relating to an offer of the Registrable Securities. (o) “Laws” mean all United States and foreign national, federal, state, and local laws, statutes, ordinances, rules, regulations, orders, treaties and decrees. (p) “Loss” has the meaning set forth in Section 2.7.1. (q) “New Registration Statement” has the meaning set forth in Section 2.1.1. (r) “Permitted Transferee” means any Affiliate of the Purchaser. (s) “Person” means any individual, firm, corporation, limited liability company, partnership, company or other entity, and shall include any successor (by merger or otherwise) of such entity. (t) “Pre-Funded Warrant” means the pre-funded warrant to purchase Common Stock issued to the Purchaser pursuant to the Purchase Agreement. (u) “Prospectus” means (i) the prospectus included in any Registration Statement, all amendments and supplements to such prospectus, including post-effective amendments and supplements, and all other material incorporated by reference in such prospectus, and (ii) any Issuer Free Writing Prospectus. (v) “Public Offering” means the offer and sale of Registrable Securities for cash pursuant to an effective registration statement under the Securities Act (other than a registration statement on Form S-4 or Form S-8 or any successor form). (w) “Purchase Agreement” means the Securities Purchase Agreement, by and between the Company and the Purchaser, dated as of November [25], 2024. (x) “Purchaser” has the meaning set forth in the preamble.

(y) “Registrable Securities” means all of (i) the Shares, (ii) the Warrant Shares, and (iii) any securities issued or issuable upon any stock split, dividend or other distribution, recapitalization or similar event with respect to the foregoing, provided, that with respect to a particular Holder, such Holder’s Shares and Warrant Shares shall cease to be Registrable Securities upon a sale pursuant to a Registration Statement or Rule 144 under the Securities Act (in which case, only such security sold by the Holder shall cease to be a Registrable Security). (z) “Registration” means registration under the Securities Act of the offer and sale to the public of any Registrable Securities under a Registration Statement. The terms “register”, “registered” and “registering” shall have correlative meanings. (aa) “Registration Expenses” has the meaning set forth in Section 2.6. (bb) “Registration Statement” or “Registration Statements” means any one or more registration statements of the Company filed under the Securities Act that covers the resale of any of the Registrable Securities pursuant to the provisions of this Agreement (including the Initial Registration Statement, the New Registration Statement and, if applicable, any Additional Registration Statement), amendments and supplements to such Registration Statements, including post-effective amendments, all exhibits and all material incorporated by reference or deemed to be incorporated by reference in such Registration Statements. (cc) “Representatives” means, with respect to any Person, any of such Person’s officers, directors, employees, agents, attorneys, accountants, actuaries, consultants, equity financing partners or financial advisors or other Person associated with, or acting on behalf of, such Person. (dd) “Rule 144” means Rule 144 under the Securities Act (or any successor rule). (ee) “SEC” means the Securities and Exchange Commission. (ff) “Securities Act” means the Securities Act of 1933, as amended. (gg) “Selling Stockholder Information” has the meaning set forth in Section 2.7.1. (hh) “Shares” means the shares of Common Stock issued or issuable to the Purchaser pursuant to the Purchase Agreement. (ii) “Shelf Takedown Request” has the meaning set forth in Section 2.1.4(a). (jj) “Suspension” has the meaning set forth in Section 2.1.3. (kk) “Transfer” means, with respect to any Registrable Security, any interest therein, or any other securities or equity interests relating thereto, a direct or indirect transfer, sale, exchange, assignment, pledge, hypothecation or other encumbrance or other disposition thereof, including the grant of an option or other right, whether directly or indirectly, whether voluntarily,

to the offer and sale of Registrable Securities by any Holders thereof from time to time in accordance with the methods of distribution elected by such Holders, and the Company shall use its reasonable best efforts to cause the Initial Registration Statement to promptly become effective under the Securities Act, provided, however, that the Company shall be permitted to file a post- effective amendment or Prospectus supplement to any effective shelf Registration Statement in lieu of filing a new Registration Statement to the extent the Company determines, and the Holders agree, that the Registrable Securities may be sold thereunder by the Holders pursuant to their intended plan of distribution. (b) Notwithstanding the registration obligations set forth in this Section 2.1.1, in the event the SEC informs the Company that all of the Registrable Securities cannot, as a result of the application of Rule 415, be registered for resale as a secondary offering on a single registration statement, the Company agrees to promptly (i) inform each of the Holders thereof and use its commercially reasonable efforts to file amendments to the Initial Registration Statement as required by the SEC and/or (ii) withdraw the Initial Registration Statement and file a new registration statement (a “New Registration Statement”), in either case covering the maximum number of Registrable Securities permitted to be registered by the SEC, on Form S-3 or such other form available to register for resale the Registrable Securities as a secondary offering; provided, however, that prior to filing such amendment or New Registration Statement, the Company shall be obligated to use its commercially reasonable efforts to advocate with the SEC for the registration of all of the Registrable Securities. Notwithstanding any other provision of this Agreement, if the SEC limits the number of Registrable Securities permitted to be registered on a particular Registration Statement as a secondary offering (and notwithstanding that the Company used diligent efforts to advocate with the SEC for the registration of all or a greater number of Registrable Securities), unless otherwise directed in writing by a Holder as to its Registrable Securities, the number of Registrable Securities to be registered on such Registration Statement will be reduced: first by Registrable Securities not acquired pursuant to the Purchase Agreement (whether pursuant to registration rights or otherwise); second by Registrable Securities represented by the Pre-Funded Warrant; and third by Registrable Securities represented by Shares. In the event the Company amends the Initial Registration Statement or files a New Registration Statement, as the case may be, under clauses (i) or (ii) above, the Company will use its commercially reasonable efforts to file with the SEC, as promptly as allowed by SEC, one or more registration statements on Form S-3 or such other form available to register for resale those Registrable Securities that were not registered for resale on the Initial Registration Statement, as amended, or the New Registration Statement. Section 2.1.2. Continued Effectiveness. The Company shall use its reasonable best efforts to keep such Registration Statement continuously effective under the Securities Act in order to permit the Prospectus forming part of the Registration Statement to be usable by Holders until the date as of which no Holder holds Registrable Securities (such period of effectiveness, the “Effectiveness Period”). Subject to Section 2.1.3, the Company shall be deemed not to have used its reasonable best efforts to keep the Registration Statement effective during the Effectiveness Period if the Company voluntarily takes any action or omits to take any action that would result in Holders of the Registrable Securities covered thereby not being able to offer and sell any Registrable Securities pursuant to such Registration Statement during the Effectiveness Period, unless such action or omission is required by applicable law.

respective counsel and (y) make such changes in such documents concerning the Holders prior to the filing thereof as such Holders, or their counsel, may reasonably request; (b) prepare and file with the SEC such amendments and post-effective amendments to such Registration Statement and supplements to the Prospectus as may be (x) reasonably requested by any Holder with Registrable Securities covered by such Registration Statement, (y) reasonably requested by any participating Holder (to the extent such request relates to information relating to such Holder), or (z) necessary to keep such Registration Statement effective during the Effectiveness Period, and comply with provisions of the applicable securities laws with respect to the sale or other disposition of all securities covered by such Registration Statement during such period in accordance with the intended method or methods of disposition by the sellers thereof set forth in such Registration Statement; (c) notify the participating Holders and the managing underwriter or underwriters, if any, and (if requested) confirm such notice in writing and provide copies of the relevant documents, as soon as reasonably practicable after notice thereof is received by the Company (a) when the applicable Registration Statement or any amendment thereto has been filed or becomes effective, and when the applicable Prospectus or any amendment or supplement thereto has been filed, (b) of any written comments by the SEC, or any request by the SEC or other federal or state governmental authority for amendments or supplements to such Registration Statement or such Prospectus, or for additional information (whether before or after the effective date of the Registration Statement) or any other correspondence with the SEC relating to, or which may affect, the Registration, (c) of the issuance by the SEC of any stop order suspending the effectiveness of such Registration Statement or any order by the SEC or any other regulatory authority preventing or suspending the use of any preliminary or final Prospectus or the initiation or threatening of any proceedings for such purposes, (d) if, at any time, the representations and warranties of the Company in any applicable underwriting agreement cease to be true and correct in all material respects and (e) of the receipt by the Company of any notification with respect to the suspension of the qualification of the Registrable Securities for offering or sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose; (d) promptly notify each selling Holder and the managing underwriter or underwriters, if any, when the Company becomes aware of the happening of any event as a result of which the applicable Registration Statement or the Prospectus included in such Registration Statement contains any untrue statement of a material fact or omits to state a material fact necessary to make the statements therein (in the case of such Prospectus or any preliminary Prospectus, in light of the circumstances under which they were made) not misleading, when any Issuer Free Writing Prospectus includes information that may conflict with the information contained in the Registration Statement, or, if for any other reason it shall be necessary during such time period to amend or supplement such Registration Statement or Prospectus in order to comply with the Securities Act and, as promptly as reasonably practicable thereafter, prepare and file with the SEC, and furnish without charge to the selling Holders and the managing underwriter or underwriters, if any, an amendment or supplement to such Registration Statement or Prospectus, which shall correct such misstatement or omission or effect such compliance; (e) to the extent the Company is eligible under the relevant provisions of Rule 430B under the Securities Act, the Company shall include in the applicable Registration Statement

such disclosures as may be required by Rule 430B under the Securities Act (referring to the unnamed selling security holders in a generic manner by identifying the initial offering of the securities to the Holders) in order to ensure that the Holders may be added to such Registration Statement at a later time through the filing of a Prospectus supplement rather than a post-effective amendment; (f) use its reasonable best efforts to prevent, or obtain the withdrawal of, any stop order or other order or notice preventing or suspending the use of any preliminary or final Prospectus; (g) promptly incorporate in a Prospectus supplement, Issuer Free Writing Prospectus or post-effective amendment such information as the managing underwriter or underwriters and the Purchaser agree should be included therein relating to the plan of distribution with respect to such Registrable Securities; and make all required filings of such Prospectus supplement, Issuer Free Writing Prospectus or post-effective amendment as soon as reasonably practicable after being notified of the matters to be incorporated in such Prospectus supplement, Issuer Free Writing Prospectus or post-effective amendment; (h) furnish to each selling Holder and each underwriter, if any, without charge, as many conformed copies as such Holder or underwriter may reasonably request of the applicable Registration Statement and any amendment or post-effective amendment or supplement thereto, including financial statements and schedules, all documents incorporated therein by reference and all exhibits (including those incorporated by reference); (i) deliver to each selling Holder and each underwriter, if any, without charge, as many copies of the applicable Prospectus (including each preliminary Prospectus) and any amendment or supplement thereto and such other documents as such Holder or underwriter may reasonably request in order to facilitate the disposition of the Registrable Securities by such Holder or underwriter (it being understood that the Company shall consent to the use of such Prospectus or any amendment or supplement thereto by each of the selling Holders and the underwriters, if any, in connection with the offering and sale of the Registrable Securities covered by such Prospectus or any amendment or supplement thereto); (j) on or prior to the date on which the applicable Registration Statement becomes effective, use its reasonable best efforts to register or qualify in connection with the Registration or qualification of such Registrable Securities for offer and sale under the securities or “Blue Sky” laws of each state and other jurisdiction as any such selling Holder or managing underwriter or underwriters, if any, or their respective counsel reasonably request in writing and do any and all other acts or things reasonably necessary or advisable to keep such Registration or qualification in effect for the Effectiveness Period, provided that the Company shall not be required to qualify generally to do business in any jurisdiction where it is not then so qualified or to take any action which would subject it to taxation or general service of process in any such jurisdiction where it is not then so subject; (k) cooperate with the selling Holders and the managing underwriter or underwriters, if any, to facilitate the timely preparation and delivery of certificates representing Registrable Securities to be sold and not bearing any restrictive legends and enable such

Registrable Securities to be in such denominations and registered in such names as the managing underwriters may request prior to any sale of Registrable Securities to the underwriters; (l) use its reasonable best efforts to cause the Registrable Securities covered by the applicable Registration Statement to be registered with or approved by such other governmental agencies or authorities as may be necessary to enable the seller or sellers thereof or the underwriter or underwriters, if any, to consummate the disposition of such Registrable Securities; (m) make such representations and warranties to the Holders being registered, and the underwriters or agents, if any, in form, substance and scope as are customarily made by issuers in public offerings similar to the offering then being undertaken; (n) enter into such customary agreements (including underwriting and indemnification agreements) and take all such other actions as the Purchaser or the managing underwriter or underwriters, if any, reasonably request in order to expedite or facilitate the Registration and disposition of such Registrable Securities; (o) obtain for delivery to the Holders and to the underwriter or underwriters, if any, an opinion or opinions from counsel for the Company dated the most recent effective date of the Registration Statement or, in the event of an Underwritten Public Offering, the date of the closing under the underwriting agreement, in customary form, scope and substance, which opinions shall be reasonably satisfactory to such Holders or underwriters, as the case may be, and their respective counsel; (p) in the case of an Underwritten Public Offering, obtain for delivery to the Company and the managing underwriter or underwriters, with copies to the Holders included in such Registration or sale, a comfort letter from the Company’s independent certified public accountants or independent auditors (and, if necessary, any other independent certified public accountants or independent auditors of any subsidiary of the Company or any business acquired by the Company for which financial statements and financial data are, or are required to be, included in the Registration Statement) in customary form and covering such matters of the type customarily covered by comfort letters as the managing underwriter or underwriters reasonably request, dated the date of execution of the underwriting agreement and brought down to the closing under the underwriting agreement; (q) cooperate with each seller of Registrable Securities and each underwriter, if any, participating in the disposition of such Registrable Securities and their respective counsel in connection with any filings required to be made with FINRA; (r) provide and cause to be maintained a transfer agent and registrar for all Registrable Securities covered by the applicable Registration Statement; (s) use its reasonable best efforts to cause all Registrable Securities covered by the applicable Registration Statement to be listed on each securities exchange on which any of the Company’s equity securities are then listed or quoted and on each inter-dealer quotation system on which any of the Company’s equity securities are then quoted;

(t) make available upon reasonable notice at reasonable times and for reasonable periods for inspection by the Purchaser, by any underwriter participating in any disposition to be effected pursuant to such Registration Statement and by any attorney, accountant or other agent retained by the Purchaser or any such underwriter, all pertinent financial and other records and pertinent corporate documents and properties of the Company, and cause all of the Company’s officers, directors and employees and the independent public accountants who have certified its financial statements to make themselves available to discuss the business of the Company and to supply all information reasonably requested by any such Person in connection with such Registration Statement; (u) in the case of an Underwritten Public Offering, cause the senior executive officers of the Company to participate in the customary “road show” presentations that may be reasonably requested by the managing underwriter or underwriters in any such offering and otherwise to facilitate, cooperate with, and participate in each proposed offering contemplated herein and customary selling efforts related thereto; (v) take no direct or indirect action prohibited by Regulation M under the Exchange Act; (w) take all reasonable action to ensure that any Issuer Free Writing Prospectus utilized in connection with any Registration complies in all material respects with the Securities Act, is filed in accordance with the Securities Act to the extent required thereby, is retained in accordance with the Securities Act to the extent required thereby and, when taken together with the related Prospectus, will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in light of the circumstances under which they were made, not misleading; and (x) take all such other commercially reasonable actions as are necessary or advisable in order to expedite or facilitate the disposition of such Registrable Securities in accordance with the terms of this Agreement. Section 2.2.2. Company Information Requests. The Company may require each seller of Registrable Securities as to which any Registration or sale is being effected to furnish to the Company such information regarding the distribution of such securities and such other information relating to such Holder and its ownership of Registrable Securities as the Company may from time to time reasonably request in writing. Each Holder agrees to furnish such information to the Company and to cooperate with the Company as reasonably necessary to enable the Company to comply with the provisions of this Agreement. Section 2.2.3. Discontinuing Registration. Each Holder agrees that, upon receipt of any notice from the Company of the happening of any event of the kind described in Section 2.2.1(d), such Holder will discontinue disposition of Registrable Securities pursuant to such Registration Statement until such Xxxxxx’s receipt of the copies of the supplemented or amended Prospectus contemplated by Section 2.2.1(d), or until such Holder is advised in writing by the Company that the use of the Prospectus may be resumed, and has received copies of any additional or supplemental filings that are incorporated by reference in the Prospectus, or any amendments or supplements thereto, and if so directed by the Company, such Holder shall deliver to the

to the indemnifying party, or (iv) in the reasonable judgment of any such Person (based upon advice of its counsel) a conflict of interest may exist between such Person and the indemnifying party with respect to such claims (in which case, if the Person notifies the indemnifying party in writing that such Person elects to employ separate counsel at the expense of the indemnifying party, the indemnifying party shall not have the right to assume the defense of such claim on behalf of such Person). If the indemnifying party assumes the defense, the indemnifying party shall not have the right to settle such action without the consent of the indemnified party. No indemnifying party shall consent to entry of any judgment or enter into any settlement which does not include as an unconditional term thereof the giving by the claimant or plaintiff to such indemnified party of an unconditional release from all liability in respect to such claim or litigation without the prior written consent of such indemnified party. If such defense is not assumed by the indemnifying party, the indemnifying party will not be subject to any liability for any settlement made without its prior written consent, but such consent may not be unreasonably withheld. It is understood that the indemnifying party or parties shall not, except as specifically set forth in this Section 2.6.3, in connection with any proceeding or related proceedings in the same jurisdiction, be liable for the reasonable fees, disbursements or other charges of more than one separate firm admitted to practice in such jurisdiction at any one time unless (x) the employment of more than one counsel has been authorized in writing by the indemnifying party or parties, (y) an indemnified party has reasonably concluded (based on the advice of counsel) that there may be legal defenses available to it that are different from or in addition to those available to the other indemnified parties or (z) a conflict or potential conflict exists or may exist (based upon advice of counsel to an indemnified party) between such indemnified party and the other indemnified parties, in each of which cases the indemnifying party shall be obligated to pay the reasonable fees and expenses of such additional counsel or counsels. Section 2.6.4. Contribution. If for any reason the indemnification provided for in Section 2.6.1 and Section 2.6.2 is unavailable to an indemnified party or insufficient in respect of any Losses referred to therein (other than as a result of exceptions or limitations on indemnification contained in Section 2.6.1 and Section 2.6.2), then the indemnifying party shall contribute to the amount paid or payable by the indemnified party as a result of such Loss in such proportion as is appropriate to reflect the relative fault of the indemnifying party on the one hand and the indemnified party or parties on the other hand in connection with the acts, statements or omissions that resulted in such Losses, as well as any other relevant equitable considerations. In connection with any Registration Statement filed with the SEC by the Company, the relative fault of the indemnifying party on the one hand and the indemnified party on the other hand shall be determined by reference to, among other things, whether any untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the indemnifying party or by the indemnified party and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The parties hereto agree that it would not be just or equitable if contribution pursuant to this Section 2.6.4 were determined by pro rata allocation or by any other method of allocation that does not take account of the equitable considerations referred to in this Section 2.6.4. No Person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any Person who was not guilty of such fraudulent misrepresentation. The amount paid or payable by an indemnified party as a result of the Losses referred to in Sections 2.6.1 and 2.6.2 shall be deemed to include, subject to the limitations set forth above, any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or

or entity, or create a presumption that the Holders are in any way acting in concert or as a group or entity with respect to such obligations or the transactions contemplated by this Agreement or any other matters, and the Company acknowledges that the Holders are not acting in concert or as a group, and the Company shall not assert any such claim, with respect to such obligations or transactions. Each Holder shall be entitled to protect and enforce its rights, including the rights arising out of this Agreement, and it shall not be necessary for any other Holder to be joined as an additional party in any proceeding for such purpose. The use of a single agreement with respect to the obligations of the Company contained herein was solely in the control of the Company, not the action or decision of any Holder, and was done solely for the convenience of the Company and not because it was required or requested to do so by any Holder. It is expressly understood and agreed that each provision contained in this Agreement is between the Company and a Holder, solely, and not between the Company and the Holders collectively and not between and among Holders. [Signature pages follow]

IN WITNESS WHEREOF, each of the undersigned has duly executed this Agreement as of the date first above written. Company: ARROWHEAD PHARMACEUTICALS, INC. By: ______________________________ Name: Title: Purchaser: AVORO LIFE SCIENCES FUND LLC By: ______________________________ Name: Xxxxx Xxxxxxx Title: Partner, Chief Operating Officer & Chief Compliance Officer