EX-10.4

**Exhibit 10.4 **

**Windward Bio Equity Incentive Plan 2025 **

**Amended and Restated Plan Regulations **

enacted pursuant to the Board resolution of June 24, 2025

In this Plan, the below mentioned terms shall have the following meanings:

The purpose of this Plan is to attract, retain and motivate our Directors, executives, Employees and Consultants, to provide additional incentives to the Participants, and thereby promoting the interests and the long-term success of the Windward Bio Group.

This Plan shall provide the Participants with the opportunity to acquire a proprietary interest in Windward Bio’s share capital in order to motivate and reinforce the commitment of the Participants to the Windward Bio Group to contribute to the potential value creation, success and prosperity of the Windward Bio Group through their work and achievement of corporate and individual goals. Such interest will provide the Participants with a stake in the future potential value creation of Windward Bio and align the focus of the Windward Bio team with that of its shareholders.

The Board shall administer this Plan insofar as the administration of this Plan has not been delegated to the Plan Committee. Whenever this Plan refers to the Board, it is understood that the Board may delegate its power or tasks under this Plan to the CC, subject to any restrictions under applicable law, the Articles of Association or the Shareholders’ Agreement, and to the extent of such delegation, any reference to the “Board” in this Plan shall mean the CC.

The Board shall appoint the Plan Committee (currently the CEO, except with respect to grants to the members of Windward Bio’s executive committee and to Directors, for which the Board shall be the Plan Committee). The Plan Committee shall execute and administer this Plan and shall have the final and binding authority to determine any other matter that is necessary or desirable for, or incidental to the administration of, this Plan (subject to the terms of this Plan), including the construction and interpretation of the Plan and the establishment and amendment of rules and regulations for its administration. The Plan Committee may appoint a Plan Administrator who is responsible for receiving and executing Option Exercise Notices and performing other administrative tasks delegated to the Plan Administrator by the Plan Committee. If no Plan Administrator is appointed, the Plan Committee shall assume all tasks that are under this Plan assigned to the “Plan Administrator”.

The Shares subject to this Plan shall be made available in the form of conditional capital or a capital range in accordance with the Articles of Association or be procured in another way, including from other forms of capital increases, from Shares acquired in the market or from third parties, or from Shares held in treasury. In its sole discretion, Windward Bio or any of its Subsidiaries or any person appointed by any of them may, in its own name or in the name of a Participant and on behalf of a Participant, subscribe to Shares, pay in the issue price and take any other action to create the Shares or direct the Participant to do so. No protection against dilution due to the issuance of new Shares, exercise of Options or otherwise shall apply, other than as provided by mandatory law.

Windward Bio shall not be required to segregate any cash or any Shares underlying the Awards, and the Plan shall constitute an unfunded plan.

Any obligation to deliver Shares under this Plan is only specifically enforceable if and when the relevant Shares are available to Windward Bio (other than by potential Share acquisitions) or can be issued without further shareholder approval.

The Board or the Plan Committee, if delegated to it, shall have full authority (subject to the provisions of this Plan and the Articles of Association) to determine, in its sole discretion, the eligible Employees, Consultants or Directors who may receive Options and/or RSUs, and the number and terms of the Options and/or RSUs to be granted to those individuals.

The grant of Awards is wholly discretionary. Any value, income or other benefit derived from any Award is not to be considered part of the Participant’s salary or compensation for the purposes of calculating any severance, resignation, termination, redundancy or other end of service or employment payments, vacation, bonuses, long-term service awards, indemnification, pension or retirement benefits, or any other payment, benefits or rights of any kind.

Subject to the terms and conditions of this Plan, the Award Agreement and the Articles of Association, each Option shall give the Participant the right to purchase one (1) Share at the Exercise Price during the Exercise Windows (as applicable) and the Exercise Period, and each RSU shall give the Participant the right to receive one (1) Share.

The Awards shall provide no shareholder rights to their holder. Only upon exercise of an Option, full payment of the Exercise Price and delivery of the Shares in the case of an Option, or delivery of Shares upon vesting of the RSU in the case of an RSU, and, in each case, filing and acceptance of an application for registration in the share register, the holder will, subject to applicable law, be entered in the share register of Windward Bio.

Unless otherwise determined by the Board, the Awards shall be granted free of charge.

With respect to any Option award, the Participant and the relevant Affiliate shall enter into an option agreement (Option Agreement), which shall set forth (i) the Grant Date, (ii) the number of granted Options, (iii) the Vesting Commencement Date, the Vesting Period and the vesting conditions, (iv) the Exercise Price, and (v) the Exercise Period, and shall include the provisions of this Plan by reference.

With respect to any RSU award, the Participant and the relevant Affiliate shall enter into an RSU agreement (RSU Agreement), which shall set forth (i) the Grant Date, (ii) the number of granted RSUs, and (iii) the Vesting Commencement Date, the Vesting Period and the vesting conditions, and shall include the provisions of this Plan by reference.

Any grant of Awards is subject to the terms of this Plan and the Award Agreement. In case of conflicts between the terms of the Plan and an Award Agreement, the provisions of such Award Agreement shall prevail, safe for the terms and conditions pursuant to Section 15.

Each Award shall be granted to the Participant personally. A Participant may not sell, pledge, assign, transfer or otherwise dispose of, any vested or unvested Award and any rights under the Award Agreement, and may not enter into any type of hedging transactions with respect to an unvested Award, in each case unless specifically permitted under the Plan and except by means of a will or in accordance with the provisions of inheritance law. The relevant Affiliate granting the Awards may at any time assign and transfer some or all of the Awards, the Award Agreement and the rights and obligations thereunder to another Affiliate or a separated Entity (without a Change of Control).

The Plan Committee may determine that any Award must be held in a restricted depository account as designated by the Plan Committee.

Any Shares delivered upon the exercise of any Option or the vesting of an RSU shall be subject to the terms and conditions of the Shareholders’ Agreement (as long as applicable), and by entering into the Award Agreement, the Participant agrees to adhere to the Shareholders’ Agreement (as long as applicable) as from the delivery of the Shares. In addition, the Participant agrees to sign an accession declaration to the Shareholders’ Agreement if so requested by Windward Bio. The Shareholders’ Agreement may include provisions regarding waiver, exclusion or restriction of subscription rights and advance subscription rights, preference rights, lock-up periods, anti-dilution protection, conversion rights, transfer restrictions, rights of first refusal, co-sale rights, drag-along rights and purchase options of Windward Bio and/or certain shareholders of Windward Bio as well as provisions governing the exercise of shareholder rights, including voting rights.

The Awards shall vest as set forth in the Award Agreement. During the Vesting Period, the Awards are unvested, and Options may not be exercised. Unvested Awards are subject to forfeiture pursuant to the terms of this Plan and vest at the end of the Vesting Period or as otherwise set forth in this Plan.

Upon vesting, each RSU shall be converted into one (1) Share. The Plan Committee may at any time and in its sole discretion decide that some or all of the vesting RSU shall be settled in cash.

Without prejudice to Section 19, and unless otherwise provided for by the Board at its discretion and at any time, the Plan Administrator may upon vesting retain (“withhold-to-cover”) and / or sell (“sell-to-cover”) such number of Shares as is necessary to cover either the actual or estimated withholding obligations as determined by the Plan Administrator.

Unless otherwise determined by the Board, the Exercise Price shall be the nominal value of the underlying Shares.

As long as Windward Bio is not Listed, vested Options may only be exercised during the Exercise Windows or on the last day of the Exercise Period, subject to other limitations set forth herein or which may be determined by the Board or the Plan Committee from time to time.

As of a Listing, vested Options may be exercised at any time during the Exercise Period, excluding during Black-out Periods and subject to other limitations set forth herein, in Windward Bio’s trading policies or which may otherwise be determined by the Board or the Plan Committee from time to time, such as pre-clearance requirements for selected persons for any trading in Shares. Exercise may remain possible under a 10b5-1 plan or equivalent plan, subject to any applicable limitations.

Options that have not been validly exercised within the Exercise Period shall lapse and be deemed forfeited, without any compensation.

In order to exercise an Option, the Participant (or his/her legal successor(s), as the case may be) must deliver to the Plan Administrator a notice of exercise in the form and with the content as prescribed by the Plan Committee or the Plan Administrator (Option Exercise Notice) at the latest on the last day of the Exercise Period. A Participant may exercise all or only parts of the Options granted to him/her. Each exercised Option shall be settled by delivering one (1) Share per Option against payment of the Exercise Price, unless the Plan Committee decides in its sole discretion that some or all of the exercised Options shall be settled in cash.

The Participant shall pay the Exercise Price within fifteen (15) calendar days from the exercise date into the bank account designated by the Plan Administrator. No Shares will be delivered until (i) the payment in full of the Exercise Price has been received by Windward Bio on the designated bank account and (ii) the Participant has provided the funds to Windward Bio or its relevant Affiliate or Windward Bio or its relevant Affiliate has successfully applied one or more of the means referred to in Section 19 paragraph 3, in each case as required pursuant to Section 19. If the Participant fails to pay the Exercise Price and / or provide the above-mentioned funds when due, the respective Options shall lapse and be deemed forfeited, without any compensation.

As of a Listing, if the last day of the Exercise Period falls within a Black-out Period and unless the Participant has given, outside a Black-out Period, the instruction to the Plan Administrator not to exercise, all exercisable Options shall automatically be exercised and hereby be deemed exercised and may be exercised by the Company on behalf of the Participant over the last three (3) trading days prior to the expiry of the Options, provided that the Options are in the money on the respective trading days. Irrespective of the foregoing, if the Board or the Plan Committee so requests, the Participant will have to sign an Option Exercise Notice within the period demanded by the Board or the Plan Committee (which can end after the lapse of the Exercise Period, which would be deemed extended accordingly).

As of a Listing, in alternative to settling an Option by delivering one (1) Share per Option against payment of the Exercise Price, the Board or the Plan Committee may at any time determine that Options which are exercised shall be “net settled”. If so determined by the Board or the Plan Committee, the Participant shall be entitled to receive a number of Shares (such Shares, the Net-

settled Shares) to be computed by dividing the Net-settlement Amount by the Reference Price, at the Board’s or the Plan Committee’s sole discretion either to be rounded up to a full number of Shares or any fraction to be compensated in cash (based on the Reference Price). For purposes of this Section 10.3, Reference Price shall mean the market price of a Share on the regulated stock exchange on which the Shares will first be Listed (closing price) as of the day of exercise of the relevant Options, and Net-settlement Amount shall mean the product of (i) the difference between the Reference Price and the Exercise Price of the Options that are exercised, and (ii) the number of Options that are exercised, as calculated by the Plan Administrator. In case of net-settlement, the Participant shall not be obliged to pay the Exercise Price upon exercise of the Options, and Windward Bio or the relevant Affiliate shall procure that the nominal value of the Shares to be newly issued as a result of the exercise of the Options (if any) be paid by or on behalf of the Participant.

The Board or the Plan Committee, as the case may be, may at its sole discretion instruct the Plan Administrator to allow a Participant the cashless exercise (exersale) of Options, in which case a Participant shall receive a cash amount equivalent to either (i) the difference between the net proceeds from the sale of all Shares underlying the Options and the Exercise Price, or such number of Shares underlying the Options that remain after coverage of the Exercise Price of the Options by the sale of underlying Shares, or (ii), in case of net-settlement as determined by the Board, the net proceeds from the sale of the Net-settled Shares, in each case less applicable deductions made in accordance with Section 19. In addition or alternatively, the Plan Administrator may be instructed by the Board or the Plan Committee to allow other mechanics, such as a sale-to-cover, i.e., the sale of such number of Shares underlying the Options as needed to cover the Exercise Price plus tax and social security amounts and to deliver the remaining underlying Shares to the Participant. The sale of the Shares or Net-settled Shares, as applicable, received upon exercise of Options may be subject to the limitations of applicable securities law provisions, the provisions of the policy of Windward Bio governing the trading in its securities, the Shareholders’ Agreement and/or any other limitations determined by the Board from time to time. In any case, even if the sale is postponed for such reason, the sale proceeds will, for purposes of this paragraph, be the actual net proceeds of the sale of the relevant Shares or Net-settled Shares, as applicable, at such later point in time.

Except as set forth in an Award Agreement, the following terms and provisions apply to Awards in the event of a termination of Continuous Service:

In the case of special circumstances and to the extent permitted by applicable law, the Board or the Plan Committee, as applicable, may grant exceptions to these rules and may exercise discretion as to final disposition of vesting and exercisability if such exceptions and exercise of discretion are to the benefit of the Participant.

A transfer of a Participant from one to another Affiliate, and a temporary leave of absence, duly authorized in writing by the relevant Affiliate, for military service, maternity, sickness or for another purpose approved by the Plan Committee, provided that the Participant’s right to reemployment or continued services is guaranteed either by a statute or by agreement, shall not be deemed a Termination of Continuous Service. However, if employment or the consulting relationship is terminated prior to the reemployment or rehire of the Participant, then Section 11 shall apply.

In the event of a Change of Control, and, for as long as Luca Santarelli is a member of the Board, unless the Board resolves otherwise with a Qualified Board Majority including the positive vote or consent of Luca Santarelli, all Awards that would be unvested at the effective date of the Change of Control shall vest in full (such Options that vest only because of the Change of Control, the COC Vested Options, and such RSU that vest only because of the Change of Control, the COC Vested RSUs) prior to the effective date of the Change of Control, at such specific date and time as shall be determined by the Board or the Plan Committee in order to enable the following actions.

Subject to the Shareholders’ Agreement (if applicable), the Participant shall have the right, and, if so demanded by the Board, the obligation to, and the Board shall use reasonable efforts to procure that the Participant is enabled, at the election of the Board, to either:

If and to the extent in the event of a Change of Control Windward Bio cannot, for whatever reason, issue or deliver Shares to the Participant upon exercise of vested Options (including COC Vested Options) or vesting of RSUs (including COC Vested RSUs), then the Participant shall be entitled to receive the COC Price in cash for each such Award that cannot be settled in the form of a Share, provided that (i) the Participant will in such case be deemed to have agreed that the payment of the COC Price is made in full and final settlement of any right (if any) of the Participant to receive such Share and (ii) if and to the extent paragraph 5 of this Section 13 applies, the COC Price to be paid shall be held in escrow in accordance with paragraphs 5 and 6 of this Section 13.

Notwithstanding anything to the contrary herein, in the event of a Change of Control and if the Participant did not elect to sell his/her Shares or vested Options, as the case may be, into the Change of Control transaction, Windward Bio (or any of its Affiliates designated by Windward Bio) shall have the unconditional right to call the exercise (regardless of any Exercise Windows) of all vested but unexercised Options (including the COC Vested Options) and/or to repurchase (or cause an Affiliate or third party to purchase), at the sole discretion of Windward Bio, all of the Participant’s vested Options (including the COC Vested Options) and/or Shares the Participant received upon the exercise of vested Options or the vesting of vested RSUs under this Plan (including Shares received pursuant to this Section 13 paragraph ((a) or ((c)) at the COC Price.

Upon request of the Board, the aggregate proceeds paid at closing of a Change of Control transaction for COC Vested Options or for Shares acquired upon exercise of COC Vested Options or upon vesting of COC Vested RSUs, as the case may be, in each case less any legally required deductions that are due beforehand, shall be held in escrow with an escrow agent designated by Windward Bio (the Escrow Amount). The Escrow Amount shall be released in full to the relevant Participant on the earlier of:

Prior to this date, partial release of the Escrow Amount shall be made, to the extent such partial release is reasonably necessary for purposes of settlement of personal income tax, social security contributions or pension liabilities by a Participant arising as a consequence of the transactions set out in this Section 13.

By accepting Awards, each Participant agrees to grant and thereby grants a power of attorney to Windward Bio to exercise, sell, assign or otherwise dispose of on behalf of the Participant such Participant’s Awards or of the Shares acquired upon the exercise of Options or vesting of RSUs, in order to comply with and give full force and effect to the provisions of this Section 13, including, without limitation, the sale in a Change of Control transaction.

Notwithstanding the foregoing provisions of this Section 13, the Board or Plan Committee, as applicable, may provide for different provisions in a particular Award Agreement, which provisions shall be deemed to override the relevant provisions of this Section 13.

In the event of a dissolution or liquidation of Windward Bio (other than in the context of a Change of Control event), Windward Bio shall use commercially reasonable best efforts to purchase all vested Options and unvested Awards at Fair Market Value.

In the event that the Board or the shareholders of Windward Bio decide upon any corporate event (including, without limitation, share split or reverse share split, share dividend, extraordinary cash dividend, recapitalization, reorganization, merger, Reverse Merger, consolidation, split-up, split-off, combination, exchange of Shares, Options or rights offering to purchase Shares at a price substantially below the market value, or similar), the Board may adjust the number, class and nominal value of Shares underlying the outstanding Awards and/or the Exercise Price or other terms of this Plan, the Award Agreements and/or the outstanding Awards, provided, however, that (1) as a principle, the Awards shall follow the destiny of the underlying securities (e.g., if shareholders exchange their Shares for shares of another parent company, the Awards will be adjusted to also relate to the shares of such new parent company), (2) the fair value of the Awards and time to realization must not be substantially impaired thereby and (3) the number of Shares underlying any Award shall always be a whole number. If deemed appropriate or required, the relevant Affiliate may also or in addition make a compensatory cash payment to a Participant.

In the event of (i) the consummation of a merger, Reverse Merger, consolidation or similar transaction following which Windward Bio is not the surviving Entity, or (ii) any other restructuring or reorganization transaction of the Windward Bio Group which results in (A) Windward Bio no longer being the parent company or the company Listed or to be Listed, (B) in case of a demerger of Windward Bio, Windward Bio being split, or (C) the disposal of the employer Subsidiary, in each case which does not constitute or lead to a Change of Control, the Board may, without additional approval or action of the Participants being required, transfer or split this Plan, including converting or rolling over all Awards granted, to the new group holding company or company to be listed (even if such company should be organized under another jurisdiction), if the shares attributed to the Awards granted confer substantially comparable rights and time to realization (or terms and conditions more favorable to the Participant) as the Shares and if the fair value of the

Awards is not substantially impaired without compensation. If, in case of a demerger of Windward Bio, another Entity than the issuer of the Award is sold in a Change of Control, Participants shall be treated as if they (also) had Awards in the Entity sold and the Board shall give effect to the relevant adjustments.

Notwithstanding anything to the contrary in this Plan or the Award Agreement, the grant of Awards under this Plan shall in no way affect the right of Windward Bio to adjust, reclassify, reorganize or otherwise change its capital or business structure, to make any offering, or to merge, consolidate, dissolve, liquidate or sell or transfer all or any part of its business or assets.

The Participant shall not disclose to any third party any information on the rules of this Plan, on the amount or conditions of his/her Award, or on any other circumstances surrounding this Plan, in each case unless the Participant is required to do so by a competent court or administrative authority under mandatory law.

The Participant acknowledges that in order to administer the Plan, the Company (including the Board and the Plan Committee), its Affiliates and the Plan Administrator may receive and process personal data relating to the Participant, including data relating to the employment, consulting or directorship relationship of the Participant and to his/her Awards and other activities in relation to the Plan, which data may be made available to the Company, its Affiliates or the Plan Administrator by either an Affiliate or the Participant directly. The Participant further acknowledges that the Company, the Affiliate and/or the Plan Administrator may use such data relating to the Participant to implement the Plan, for administrative and transactional services in connection with this Plan and any Award. The Participant agrees and authorizes the Company, any Affiliate and the Plan Administrator (i) to access, store or otherwise process any personal data and information relating to the Participant; and (ii) to transfer, on a confidential basis, such personal data and information to any other Affiliate, the Board, the Plan Committee or the Plan Administrator and/or any person or third party authorized by the relevant Affiliate and/or the Board, the Plan Committee or the Plan Administrator, wherever located, and to this end being transmitted across national borders, including in any country or territory that may not provide the same protection for the information as such Participant’s home country, for storage and processing to the extent necessary or useful for the implementation of and for performing administrative and transactional services in connection with the Plan and any Award. Any transfer of a Participant’s personal data from Switzerland or a country within the EU or the EEA to a third country is subject to appropriate safeguards, including, without limitation, in the form of EU standard contractual clauses, or applicable derogations provided for under applicable law.

The grant of any Awards to the Participant in the future is in the sole discretion of the Board in accordance with the terms of the Plan from time to time. The establishment of this Plan, the granting of Awards pursuant to the Plan, the payment of any benefits pursuant to the Plan, or any action of Windward Bio or any of its Affiliates, the Board, the Plan Committee or the Plan Administrator are not intended to and shall not be held or construed to confer upon any Participant any right (legal or otherwise) to the continued grant of Awards.

Neither the establishment of this Plan nor the granting of Awards shall be held or construed to confer upon any Participant any right for continued employment with, or service for, Windward Bio or any of its Affiliates or as a waiver of Windward Bio’s or the relevant Affiliate’s right to terminate the employment, mandate or consulting relationship of, or any other agreement with, the Participant at any time for any reason.

Windward Bio or its relevant Affiliate shall bear all costs, taxes, social security contributions, pension related payments (if any) and duties that in accordance with applicable laws and regulations are to be borne by Windward Bio and its Affiliates related to the assignment, transfer and/or issue of Shares to the Participant, in particular the stamp duties levied by the Swiss Federal Tax Administration.

All costs, taxes, social security contributions, pension related payments (if any) and duties for which the Participant is liable in accordance with applicable laws and regulations shall be borne by himself/herself, in particular income or capital gain taxes, if any, in connection with the grant and vesting of Awards, the exercise of Options or the delivery of Shares upon exercise of an Option or vesting of an RSU as well as all possible costs, taxes and duties in case of resale or further transfer of the acquired or received Shares. The Participant shall be responsible for the necessary declarations required under applicable tax laws.

Any Affiliate shall be entitled, in its sole discretion, to satisfy any federal, state or local tax withholding obligation, or make or withhold any contributions to social security, pensions and any other duty(ies) which an Affiliate may be required to withhold or pay as well as any other duty levied on an Affiliate in this respect, relating to an Award, its vesting, the exercise of an Option or Shares received upon exercise of an Option or vesting of an RSU or, or otherwise, by any of the following means (in addition to any such Affiliate’s right to withhold from any compensation payable to the Participant by any Affiliate), or by a combination of such means: (i) causing the Participant to make a cash payment; (ii) withholding Shares from any Shares to be delivered or otherwise issuable to the Participant in connection with an Award (“withhold-to-cover”); (iii) forfeiting outstanding Awards; (iv) selling on behalf of the Participant any of the Shares to which he/she is entitled under this Plan and withhold the sale proceeds (“sell-to-cover”, including by means of a “cashless exercise” or an Affiliate acting as agent to sell Shares to satisfy such withholding requirements); (v) withholding cash if Awards are settled in cash, or (v) any such other method as the Plan Committee or the Plan Administrator deem appropriate; provided, in each case, that the Participant does not provide the funds to Windward Bio or its relevant Affiliate if so requested as determined by Windward Bio.

Windward Bio and its Affiliates shall have the right to notify the tax authorities of the grant and vesting of any Award and the exercise of any Option if so required by applicable law and regulations.

By entering into an Award Agreement, the Participant acknowledges that Windward Bio and its Affiliates do not give any representations with respect to the tax treatment of the Awards or any Shares received upon vesting of an RSU or exercise of an Option or any other event or transaction relating to the Shares or Awards, and even a tax ruling is no guarantee that tax authorities may not take a different view at a later stage or in other circumstances or that applicable law or practice or changes thereof demand otherwise.

Each Participant undertakes to comply with all applicable laws regarding insider trading and similar matters as well as with the trading policy of Windward Bio when trading in securities, as amended from time to time.

The Board may amend, suspend or discontinue this Plan or the Awards granted hereunder at any time. The amendment, suspension or discontinuance of this Plan shall not, without the consent of the Participant, alter or impair the rights of the Participant under any Awards previously granted to him/her, unless mandatory law so requires or if fairly compensated by other grants or cash payments.

In particular, the Board may effect, at any time, the cancellation of some or all outstanding Awards under this Plan and to replace them and grant in substitution therefor new Awards covering the same or different number of Shares but with a reduced exercise price per Share based on the Fair Market Value on the new award grant date whereby the terms of a re-grant may not be improved in favor of the Participants in comparison to the granted Awards which have been cancelled.

The invalidity or non-enforceability of any term of this Plan or an Award Agreement shall not affect the validity or enforceability of any other provision of this Plan or such Award Agreement, which shall remain in full force and effect.

The terms applicable to Participants in each country may vary due to local laws. Therefore, adjustments may be made where necessary or appropriate. Variations, if any, shall be made by a country specific appendix, approved by the Plan Committee and attached to this Plan.

This Plan was approved by the Board on June 24, 2025. This Plan restates and amends the Equity Incentive Plan approved by the Board on February 25, 2025, in its entirety. This Plan shall remain effective as long as Awards exist according to this Plan.

No new Awards shall be issued under this Plan following a Listing.

The formation, existence, construction, performance, validity and all aspects whatsoever of this Plan, any term of this Plan, any Award Agreement and any Awards granted thereunder, including any rights and obligations arising out of or in connection with the same, shall be governed by, and construed in accordance with, substantive Swiss law (with the exception of the conflict of law rules).

The exclusive place of jurisdiction for any dispute arising out of or in connection with this Plan or any Award Agreement and any Awards granted thereunder shall be Basel, Switzerland.

**Windward Bio Group AG **

Luca Santarelli

Chairperson of the Board

**Annex 1 **

**Option Agreement – Template1 **

**Option Agreement **

| | | | : | :----------------------------------------------------------------------------------------------------------- | | 1 | NTD: Not to be used for U.S. Participants. Please refer to the Template RSU Agreement for U.S. Participants. |

The Plan, as amended by the Board from time to time, is hereby incorporated in this Option Agreement by reference. Unless otherwise defined herein, capitalized terms used in this Option Agreement shall have the same meaning as in the Plan. A copy of the Plan as in effect on the Grant Date is attached hereto as Exhibit A.

The Company hereby grants to the Participant [•] Options [For True-up EIP Awards:, of which [•] Options2 (the Second Tranche Options) are deemed allocated in connection with the closing of the second tranche of the Company’s series B financing (the Second Tranche Closing)], subject to the terms and conditions set out in the Plan and in this Option Agreement.

| | | | : | :---------------------------------------------------------------------------------- | | 2 | NTD: 1/3 of all Options reflecting the split into first tranche and second tranche. |

| | | | : | :------------------------------------------------------------------------------------------------------------- | | 3 | NTD: Last day of the month prior to the start date of the Participant. For True-up EIP Awards, March 31, 2026. |

| | | | : | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | 4 | NTD: For new hires, Awards will be subject to a 4-year vesting with a 1-year cliff vesting (25%) and monthly vesting thereafter. For founders, Directors and existing employees and consultants, Awards will be subject to 4-year vesting on a monthly basis (no cliff). For True-up EIP Awards, Awards will be subject to 3-year vesting on a monthly basis (no cliff). |

| | | | : | :-------------------------------------------------------------------------------------------------- | | 5 | NTD: If remainder cannot be divided by 36, excess Options to be added to number of Options under A. |

| | | | : | :-------------------------------------------------------------------------------------------------- | | 5 | NTD: If remainder cannot be divided by 36, excess Options to be added to number of Options under A. |

| | | | : | :----------------------------------------------------------------------------------------------- | | 6 | NTD: If number cannot be divided by 48, excess Options to be added to number of Options under 1. |

| | | | : | :----------------------------------------------------------------------------------------------- | | 7 | NTD: If number cannot be divided by 36, excess Options to be added to number of Options under 1. |

To the extent that a Plan Administrator shall provide for an electronic exercise or the Plan provides for an automatic or deemed exercise of Options, the Participant hereby exercises his/her Options, but with effect as of his/her electronic exercise or the relevant automatic or deemed exercise.

The Participant acknowledges and agrees that he/she has read and understood the terms of the Plan, which he/she fully and unconditionally accepts. In particular, without limitation, the Participant hereby adheres to the Shareholders’ Agreement with effect of the acquisition of Shares upon exercise of Options. In addition, the Participant agrees to sign an accession declaration to the Shareholders’ Agreement if so requested by Windward Bio.

This Option Agreement may be executed and delivered by each party in separate counterparts, each of which when so executed and delivered shall be deemed an original and all of which taken together shall constitute one and the same Option Agreement. This Option Agreement and any amendments hereto, to the extent signed and delivered by means of electronic signature or e-signature (irrespective of whether the relevant electronic signature or e-signature has been issued by a provider recognized or accredited under applicable law or not) or other electronic transmission (e.g., e-mail delivery in .pdf format or similar format), shall be treated in all manner and respects as an original contract and shall be considered to have the same binding legal effects as if it were the original signed version thereof delivered in person.

In case of conflicts between the terms of the Plan and this Option Agreement, the provisions of this Option Agreement shall prevail, safe for the terms and conditions pursuant to Section 15 of the Plan.

The formation, existence, construction, performance, validity and all aspects whatsoever of this Option Agreement and the Options granted hereunder, including any rights and obligations arising out of or in connection with the same, shall be governed by, and construed in accordance with, substantive Swiss law (with the exception of the conflict of law rules).

The exclusive place of jurisdiction for any dispute arising out of or in connection with this Option Agreement and the Options granted hereunder shall be Basel, Switzerland.

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*[Signatures on the next page] *

Annex 2 to the Windward Bio Equity Incentive Plan 2025 (Updated in connection with the Company’s Series B Financing, as approved by the Board on April 16, 2026)

**Annex 2 **

**RSU Agreement – Template – U.S. Participants **

**RSU Agreement **

Annex 2 to the Windward Bio Equity Incentive Plan 2025

The Plan, as amended by the Board from time to time, is hereby incorporated in this RSU Agreement by reference. Unless otherwise defined herein, capitalized terms used in this RSU Agreement shall have the same meaning as in the Plan. A copy of the Plan as in effect on the Grant Date is attached hereto as Exhibit A.

The Company hereby grants to the Participant [•] RSUs [For True-up EIP Awards:, of which [•] RSUs8 (the Second Tranche RSUs) are deemed allocated in connection with the closing of the second tranche of the Company’s series B financing (the Second Tranche Closing)], subject to the terms and conditions set out in the Plan and in this RSU Agreement.

| | | | : | :------------------------------------------------------------------------------- | | 8 | NTD: 1/3 of all RSUs reflecting the split into first tranche and second tranche. |

| | | | : | :--------------------------------------------------------------------------------------------------- | | 9 | NTD: From a U.S. securities law perspective, the individual must be in service on the date of grant. |

Annex 2 to the Windward Bio Equity Incentive Plan 2025

Annex 2 to the Windward Bio Equity Incentive Plan 2025

Annex 2 to the Windward Bio Equity Incentive Plan 2025

The Participant acknowledges and agrees that he/she has read and understood the terms of the Plan, which he/she fully and unconditionally accepts. In particular, without limitation, the Participant hereby adheres to the Shareholders’ Agreement with effect of the acquisition of Shares upon vesting of an RSU. In addition, the Participant agrees to sign an accession declaration to the Shareholders’ Agreement if so requested by Windward Bio.

This RSU Agreement may be executed and delivered by each party in separate counterparts, each of which when so executed and delivered shall be deemed an original and all of which taken together shall constitute one and the same RSU Agreement. This RSU Agreement and any amendments hereto, to the extent signed and delivered by means of electronic signature or e-signature (irrespective of whether the relevant electronic signature or e-signature has been issued by a provider recognized or accredited under applicable law or not) or other electronic transmission (e.g., e-mail delivery in .pdf format or similar format), shall be treated in all manner and respects as an original contract and shall be considered to have the same binding legal effects as if it were the original signed version thereof delivered in person.

In case of conflicts between the terms of the Plan and this RSU Agreement, the provisions of this RSU Agreement shall prevail, safe for the terms and conditions pursuant to Section 15 of the Plan.

Annex 2 to the Windward Bio Equity Incentive Plan 2025

The formation, existence, construction, performance, validity and all aspects whatsoever of this RSU Agreement and the RSU granted hereunder, including any rights and obligations arising out of or in connection with the same, shall be governed by, and construed in accordance with, substantive Swiss law (with the exception of the conflict of law rules).

The exclusive place of jurisdiction for any dispute arising out of or in connection with this RSU Agreement and the RSU granted hereunder shall be Basel, Switzerland.

Notwithstanding any other provision hereof, the Company reserves the right to pay the Participant the cash equivalent of Shares, in part or in full satisfaction of the delivery of Shares in connection with the vesting of an RSU, and, to the extent applicable, references in this RSU Agreement to Shares to be delivered in connection with the RSU will include the potential payment of the cash equivalent pursuant to such right.

The delivery of Shares in respect of an RSU shall occur within sixty (60) days immediately following the date the RSU becomes a Vested RSU, and in all circumstances such delivery is intended to comply with United States Treasury Regulation Section 1.409A-1(b)(4) and will be construed and administered in such a manner. Subject to the satisfaction of tax withholding obligations (the Withholding Obligation), in the event one or more RSUs vest, the Company shall deliver to the Participant one (1) Share for each RSU that vests on the applicable vesting date(s). Each delivery date determined by this paragraph is referred to as an Original Delivery Date. If the Original Delivery Date falls on a date that is not a business day, delivery shall instead occur on the next following business day. In addition, if:

Annex 2 to the Windward Bio Equity Incentive Plan 2025

Notwithstanding the foregoing provisions of this Section 8.1, and notwithstanding the provisions of Section 13 of the Plan relating to the holding of proceeds in escrow in connection with a Change of Control and the delayed settlement of such proceeds (the Escrow Provisions), the Escrow Provisions (a) shall not apply to any RSU that have met the Service-Based Requirement as of immediately prior to the Change of Control; and (b) shall apply to RSUs that have not met the Service-Based Requirement as of immediately prior to the Change of Control, except that clause (ii) of the Escrow Provisions shall be deemed to refer to the earlier of (A) the date six (6) months after the effective date of the Change of Control and (B) March 15 of the year following the year in which the Change of Control occurs.

The Participant acknowledges that, regardless of any action taken by the Company, the ultimate liability for all income tax, social insurance, payroll tax, fringe benefits tax, payment on account or other tax-related items related to the Participant’s participation in the Plan and legally applicable to the Participant (Tax-Related Items) is and remains the Participant’s responsibility (in the event of death, the Participant’s heirs) and may exceed the amount actually withheld by the Company. The Company and/or any Affiliate shall withhold taxes upon vest and/or sale according to the requirements under applicable laws, rules, and regulations, including withholding taxes at source. Prior to any relevant taxable or tax withholding event, as applicable, the Participant agrees to make adequate arrangements satisfactory to the Company and/or the Participant’s employer (if not the Company) to satisfy all Tax-Related Items. In this regard, the Participant authorizes the Company or its agent to satisfy their withholding obligations with regard to all Tax-Related Items, if any, by any of the following means or by a combination of such means: (i) withholding from any compensation otherwise payable to the Participant by the Company or the Participant’s employer; (ii) causing the Participant to make a cash payment; (iii) entering on the Participant’s behalf (pursuant to this authorization without further consent) into a “same day sale” commitment with a broker dealer that is a member of the Financial Industry Regulatory Authority (a FINRA Dealer) whereby the Participant irrevocably elects to sell a portion of the Shares to be delivered under the RSU to satisfy the Tax-Related Items and whereby the FINRA Dealer irrevocably commits to forward the proceeds necessary to satisfy the Tax-Related Items directly to the Company and/or its Affiliates; or (iv) withholding Shares from the Shares to be delivered or otherwise issuable to the Participant in connection with the RSU with a Fair Market Value (measured as of the date Shares are delivered to the Participant or, if and as determined by the Company, the date on which the Tax-Related Items are required to be calculated) equal to the amount of such Tax-Related Items. The Company does not guarantee that the Participant will be able to satisfy any Tax-Related Items through any of the methods described in the preceding sentence and in all

Annex 2 to the Windward Bio Equity Incentive Plan 2025

circumstances the Participant remains responsible for timely and fully satisfying the Tax-Related Items. If the obligation for Tax-Related Items is satisfied by withholding in Shares, for tax purposes, the Participant is deemed to have been delivered the full number of Shares subject to the Vested RSUs, notwithstanding that a number of the Shares are held back solely for the purpose of paying the Tax-Related Items. The Participant will not be entitled to receive from the Company any shares to be delivered upon vesting of the RSU, prior to the full payment of any tax.

In connection with the Participant’s acquisition of the Shares under the RSU, the Participant represents to the Company the following:

Annex 2 to the Windward Bio Equity Incentive Plan 2025

This RSU Agreement is intended to be exempt from Section 409A of the U.S. Internal Revenue Code of 1986, and the related Treasury regulations promulgated thereunder (Section 409A) and shall be administered and interpreted consistently with such intent. This RSU Agreement may be unilaterally amended by the Company without Participant consent if the Company determines, in its sole discretion, that such amendment is necessary to ensure the provisions of this RSU Award agreement comply with Section 409A.

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Annex 2 to the Windward Bio Equity Incentive Plan 2025

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