**
**Exhibit 10.50**

**ADVERUM BIOTECHNOLOGIES, INC.**

**NON-EMPLOYEE DIRECTOR COMPENSATIONPOLICY**

**ADOPTEDBYTHE BOARDOFDIRECTORS: FEBRUARY 14, 2019**

Each member of the board of directors (the“***Board***”) of Adverum Biotechnologies, Inc. (the “***Company***”) who is a Non-Employee Director (as defined in the Adverum Biotechnologies, Inc. 2014 Equity IncentiveAward Plan (the “***Plan***”)) will be eligible to receive cash and equity compensation as set forth in this Adverum Biotechnologies, Inc. Non-Employee Director Compensation Policy (this“***Policy***”). The cash and equity compensation described in this Policy will be paid or granted, as applicable, automatically and without further action of the Board to each Non-EmployeeDirector who is eligible to receive such cash or equity compensation, unless such Non-Employee Director declines the receipt of such cash or equity compensation by written notice to the Company. This Policy,as adopted on February 14, 2019, will become effective immediately and will remain in effect until it is revised or rescinded by further action of the Board. Capitalized terms not explicitly defined in this Policy but defined in the Plan willhave the same definitions as in the Plan. 

 
**1.**
**CASH COMPENSATION.**

**(a)****Annual Retainers.** Each Non-Employee Director will be eligible to receive thefollowing annual retainers for service as (i) a member and/or chair of the Board and (ii) a member or chair of a committee of the Board (“***Committee***”) set forth below, as applicable. 

 

**Board or Committee**
  
**Type of Retainer***
  **Amount (Per Year)****Board**  Chair  $35,000  Member  $40,000**Audit Committee**  Chair  $20,000  Member (Non-Chair)  $10,000**Compensation Committee**  Chair  $15,000  Member (Non-Chair)  $7,500**Nominating and Corporate Governance Committee**  Chair  $10,000  Member (Non-Chair)  $5,000
 
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The chair of the Board is eligible to receive a retainer for service as the chair and an additional retainerfor service as a member of the Board. The chair of each Committee is eligible to receive a retainer for service as the chair, but not an additional retainer for service as a member of the Committee. 

The annual retainers will be paid on the last day of the quarter and partial service for that quarter will receive *pro rata* treatment.

**(b)****Expenses.** Each Non-Employee Director will be eligible for reimbursement from theCompany for all reasonable out-of-pocket expenses incurred by the Non-Employee Director in connection with his or her attendanceat Board and Committee meetings. 
**

To the extent that any taxable reimbursements are provided to a Non-Employee Director, they will be provided in accordance with Section 409A of the Internal Revenue Code of 1986, as amended, and the Treasury Regulations and other guidance thereunder and any state law ofsimilar effect, including, but not limited to, the following provisions: (i) the amount of any such expenses eligible for reimbursement during the Non-Employee Director’s taxable year may not affectthe expenses eligible for reimbursement in any other taxable year; (ii) the reimbursement of an eligible expense must be made no later than the last day of the Non-Employee Director’s taxable yearthat immediately follows the taxable year in which the expense was incurred; and (iii) the right to any reimbursement may not be subject to liquidation or exchange for another benefit. 

**2.********EQUITY COMPENSATION********.** The options described in this Policy will be grantedunder the Plan and will be subject to the terms and conditions of (i) this Policy, (ii) the Plan and (iii) the form of Option Agreement approved by the Board for the grant of options toNon-Employee Directors under the Plan. 

**(a)** **Initial Grants.** Each person whofirst becomes a Non-Employee Director, whether through election by the stockholders of the Company or appointment by the Board to fill a vacancy, automatically will be granted a Nonstatutory Stock Option topurchase 70,000 shares of Common Stock (an “***Initial Option***”) on the date of his or her initial election or appointment to be a Non-Employee Director. 

**(b)** **Annual Grants.** On the date of each annual meeting of the Company’s stockholders (starting with the 2019 annualmeeting of stockholders), each person who is then a Non-Employee Director and will be continuing as a Non-Employee Director following the date of such annual meeting(other than any Non-Employee Director receiving an Initial Option on the date of such annual meeting) automatically will be granted a Nonstatutory Stock Option to purchase 45,000 shares of Common Stock (an“***Annual Option***”); *provided, however*, that if the Non-Employee Director has not served as a Non-Employee Director for 12 months prior tothe applicable annual meeting, the number of shares will be pro-rated for the number of full months served on the Board prior to the date of grant, rounded to the nearest whole share. For example, if a Non-Employee Director was appointed in September 2018, and the 2019 annual meeting of stockholders is held in June 2019, such Non-Employee Director would receive an AnnualOption at the 2019 annual meeting of stockholders for 30,000, or 8/12 of 45,000, shares. 

**(c) Terms of Options.**

**(i)**Exercise Price. The exercise price of each Initial Option and Annual Option will be equal to 100% of the Fair Market Value ofthe Common Stock subject to such option (as determined in accordance with the Plan) on the date such option is granted. 

**(ii)** Vesting. Each Initial Option and Annual Option will vest and become exercisable as follows: 

**(A)**Each Initial Option will vest and become exercisable in equal annual installments on each of the first three anniversaries of thedate of grant of such option, provided that the Non-Employee Director has not had a Termination of Service prior to each such date; *provided, however*, that the vesting shall accelerate, and of theInitial Option shall become fully vested and exercisable, upon the consummation of a Change in Control. 

 
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**(B)** Each Annual Option will vest and become exercisable on the earlier of(i) the date of the next annual meeting of the Company’s stockholders (the “***Next Annual Meeting***”), (ii) the first anniversary of the date of grant of such option, provided that theNon-Employee Director has not had a Termination of Service prior to such date, or (iii) the consummation of a Change in Control. 

 
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