Extension Right. Section 39 of the Lease is hereby deleted and replaced in its entirety with the following:

Extension Right. Tenant shall have 2 rights (each, an “Extension Right”) to extend the term of this Lease for 1 year each (each, an “Extension Term”) on the same terms and conditions as this Lease (other than with respect to Base Rent) by giving Landlord written notice of its election to exercise the Extension Right at least 9 months prior, and no earlier than 12 months prior, to the expiration of the Base Term of the Lease or the prior Extension Term.

Regulatory Extension. A Holder’s Option Agreement may provide that if the exercise of the Option following the termination of the Holder’s status as a Service Provider would be prohibited at any time solely because the issuance of shares would violate the registration requirements under the Securities Act, then the Option shall terminate on the earlier of (in the expiration of the term of the Option set forth in Section 8 hereof or # the expiration of a period of three (3) months after the termination of the Holder’s status as a Service Provider during which the exercise of the Option would not be in violation of such registration requirements.

Extension Request. The Borrower shall provide the applicable Extension Request at least fifteen (15) Business Days (or such shorter period as agreed to by the Administrative Agent) prior to the date on which Lenders under the Existing Term Loan Tranche or Existing Revolver Tranche, as applicable, are requested to respond, and shall agree to such procedures, if any, as may be established by, or acceptable to, the Administrative Agent, in each case acting reasonably to accomplish the purposes of this [Section 2.18]. No Lender shall have any obligation to agree to have any of its Term Loans of any Existing Term Loan Tranche amended into Extended Term Loans or any of its Revolving Credit Commitments amended into Extended Revolving Credit Commitments, as applicable, pursuant to any Extension Request. Any Lender holding a Loan under an Existing Term Loan Tranche (each, an “Extending Term Lender”) wishing to have all or a portion of its Term Loans under the Existing Term Loan Tranche subject to such Extension Request amended into Extended Term Loans and any Revolving Credit Lender (each, an “Extending Revolving Credit Lender”) wishing to have all or a portion of its Revolving Credit Commitments under the Existing Revolver Tranche subject to such Extension Request amended into Extended Revolving Credit Commitments, as applicable, shall notify the Administrative Agent (each, an “Extension Election”) on or prior to the date specified in such Extension Request of the amount of its Term Loans under the Existing Term Loan Tranche or Revolving Credit Commitments under the Existing Revolver Tranche, as applicable, which it has elected to request be amended into Extended Term Loans or Extended Revolving Credit Commitments, as applicable, (subject to any minimum denomination requirements imposed by the Administrative Agent). In the event that the aggregate principal amount of Term Loans under the Existing Term Loan Tranche or Revolving Credit Commitments under the Existing Revolver Tranche, as applicable, in respect of which applicable Term Lenders or Revolving Credit Lenders, as the case may be, shall have accepted the relevant Extension Request exceeds the amount of Extended Term Loans or Extended Revolving Credit Commitments, as applicable, requested to be extended pursuant to the Extension Request, Term Loans or Revolving Credit Commitments, as applicable, subject to Extension Elections shall be amended to Extended Term Loans or Revolving Credit Commitments, as applicable, on a pro rata basis (subject to rounding by the Administrative Agent, which shall be conclusive) based on the aggregate principal amount of Term Loans or Revolving Credit Commitments, as applicable, included in each such Extension Election.

Extension; Waiver. At any time prior to the Effective Time, the parties hereto, may, # by action taken or authorized by the ​ Board and approved by the Bank, extend the time for the performance of any of the obligations or other acts of the other parties hereto, # waive any inaccuracies in the representations and warranties contained herein or in any document delivered pursuant hereto and # waive compliance with any of the agreements or conditions contained herein. Any agreement on the part of a party hereto to any such extension or waiver shall be valid only if set forth in a written instrument signed on behalf of such party. Such extension or waiver shall not be deemed to apply to any time for performance, inaccuracy in any representation or warranty, or noncompliance with any agreement or condition, as the case may be, other than that which is specified in the extension or waiver. The failure of any party to this Agreement to assert any of its rights under this Agreement or otherwise shall not constitute a waiver of such rights, nor shall any single or partial exercise of any such right, or any abandonment or discontinuance of steps to enforce such right, or any course of conduct, preclude any other or further exercise thereof or the exercise of any other right. The rights and remedies of the parties hereunder are cumulative and are not exclusive of any rights or remedies which they would otherwise have hereunder.

Extension Offers. Pursuant to one or more offers (each, an “Extension Offer”) made from time to time by the Borrowers to all Lenders of Loans with a like Maturity Date, the Borrowers may extend the Maturity Date of each such Lender’s Revolving Facility Commitments and, subject to Section 2.22(3)(b), otherwise modify the terms of such Revolving Facility Commitments pursuant to the terms of the relevant Extension Offer, including by increasing the interest rate or fees payable in respect to such Revolving Facility Commitments (each, an “Extension,” and each group of Revolving Facility Commitments so extended, as well as the original Revolving Facility Commitments not so extended, being a “tranche”). Each Extension Offer will specify the minimum amount of Revolving Facility Commitments with respect to which an Extension Offer may be accepted, which will be an integral multiple of $1.0 million and an aggregate principal amount that is not less than $25.0 million (or # if less, the aggregate principal amount of such Revolving Facility Commitments or # such lesser minimum amount as is approved by the Administrative Agent, such consent not to be unreasonably withheld, conditioned or delayed), and shall be offered on a pro rata basis to all Lenders having Revolving Facility Commitments with a like Maturity Date. If the aggregate outstanding principal amount of Loans and Revolving Facility Commitments (calculated on the face amount thereof) in respect of which Lenders have accepted an Extension Offer exceeds the maximum aggregate principal amount of Loans and Revolving Facility Commitments offered to be extended pursuant to an Extension Offer, then the Loans and Revolving Facility Commitments of such Lenders will be extended ratably up to such maximum amount based on the Revolving Facility Commitments of the Lenders that have accepted such Extension Offer. There is no requirement that any Extension Offer or Extension Amendment (defined as follows) be subject to any “most favored nation” pricing provisions. Each Lender accepting an Extension Offer is referred to herein as an “Extending Lender,” and the Loans and Revolving Facility Commitment held by such Lender (and so extended) accepting an Extension Offer are referred to herein as “Extended Loans” and “Extended Commitments”.

Extension Amendments. The Lenders hereby irrevocably authorize the Administrative Agent to enter into amendments to this Agreement and the other Loan Documents (an “Extension Amendment”) with the Borrowers as may be necessary in order to establish new tranches in respect of Extended Commitments (and related Extended Loans) and such technical amendments as may be necessary or appropriate in the reasonable opinion of the Administrative Agent and the Borrowers in connection with the establishment of such new tranches, in each case, on terms consistent with this Section 2.22. This Section 2.22 supersedes any provisions in Section 10.08 to the contrary. Except as otherwise set forth in an Extension Offer, there will be no conditions to the effectiveness of an Extension Amendment. Extensions will not constitute a voluntary or mandatory payment or prepayment for purposes of this Agreement.

Patent Term Extension. If elections with respect to obtaining patent term extension or supplemental protection certificates or their equivalents in any country with respect to Northern Patent Rights or other patent rights covering Licensed Products or their manufacture or use are available, Spero shall have the sole right to make any such elections. In case Spero decides not to make such election with respect to a Licensed Product, Northern has the right but no obligation to do so in its own name and at its own expense with respect to a product containing an Other Compound (but not with respect to a Licensed Product).

Extension of Commitments. Effective as of the Extension Date, the Termination Date of the Commitment of each Extending Lender identified on [Schedule I] shall be extended to January 27, 2022, which, for purposes of [Section 2.08(d)(ii)] of the Credit Agreement, shall be the “Current Termination Date.”

Acceleration, Extension, Etc. The Board of Directors may, in its sole discretion, # accelerate the date or dates on which all or any particular Option or Options may be exercised or # extend the period or periods of time during which all, or any particular, Option or Options may be exercised.