StageZero Life Sciences Ltd. — Capital/Financing Update 2022

Aug 23, 2022

SECOND SUPPLEMENTAL INDENTURE

This second supplemental indenture (this “ Second Supplemental Indenture ”) dated August 18, 2022

BETWEEN:

STAGEZERO LIFE SCIENCES LTD.

(hereinafter referred to as the “ Corporation ”)

AND:

TSX TRUST COMPANY

(hereinafter referred to as the “ Trustee ”)

WHEREAS the Corporation changed its name from “ Genenews Limited ” to “ StageZero Life Sciences Ltd. ” pursuant to Articles of Amendment dated June 20, 2019;

AND WHEREAS the Corporation, under its predecessor name “Genenews Limited”, and the Trustee entered into a Debenture Indenture dated December 23, 2016, which, together with all amendments, restatements, supplements, or other modifications thereto, is hereinafter referred to as the “ Indenture ”;

AND WHEREAS , pursuant to the Indenture, the aggregate principal amount of Debentures the Corporation is authorized to issue thereunder is unlimited;

AND WHEREAS , pursuant to the Indenture, the Corporation may, from time to time, issue Additional Debentures in one or more series and such Additional Debentures shall be issued pursuant to the terms and conditions of a Supplemental Indenture entered into between the Corporation and the Trustee that is applicable to such series;

AND WHEREAS the Corporation entered into the First Supplemental Indenture on February 19, 2020 with the Trustee pursuant to which certain convertible debentures were issued;

AND WHEREAS the Corporation desires to issue 8% unsecured convertible debenture subscription agreements pursuant to which the subscribers thereto will each purchase February 2024 Convertible Unsecured Debentures (as defined below) of the Corporation for a subscription price of $1,000 per February 2024 Convertible Unsecured Debenture (the “ February 2024 Convertible Unsecured Debenture Offering ”);

AND WHEREAS pursuant to Section 13.1 of the Indenture the parties hereto may enter into this Second Supplemental Indenture providing for the issuance of the February 2024 Convertible Unsecured Debentures under the Indenture and the Corporation wishes to create and issue the February 2024 Convertible Unsecured Debentures subject to the terms and conditions of the Indenture as modified by this Second Supplemental Indenture;

AND WHEREAS the foregoing recitals are made as representations and statements of fact by the Corporation and not the Trustee;

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NOW THEREFORE THIS SECOND SUPPLEMENTAL INDENTURE WITNESSES that in consideration of the respective covenants and agreements contained herein and for other good and valuable consideration (the receipt and sufficiency of which are acknowledged), the Corporation and the Trustee covenant and agree, for the benefit of each other and for the equal and rateable benefit of the holders of the February 2024 Convertible Unsecured Debentures, as follows:

1. Definitions . Capitalized words or expressions used in this Second Supplemental Indenture shall have the meanings given to such terms in the Indenture, unless otherwise defined herein, as follows:

2. a. “ Common Shares ” means the common shares of the Corporation and any shares of the Corporation or its successor or assigns into which such common shares of the Corporation are converted or exchanged;

3. b. “ Conversion Date ” has the meaning ascribed thereto in Section 2(d);

4. c. “ Conversion Notice ” has the meaning ascribed thereto in Section 2(d);

5. d. “ Conversion Price ” has the meaning ascribed thereto in Section 2(d);

6. e. “ Current Market Price ” at any date, means the volume weighted average price per share at which the Common Shares have traded:

   • i. on the TSX;

   • ii. if the Common Shares are not listed on the TSX, on any stock exchange upon which the Common Shares are listed as may be selected for this purpose by the Directors, acting reasonably and in good faith; or

   • iii. if the Common Shares are not listed on any stock exchange, on any over-thecounter market,

during the 20 consecutive trading days (on each of which at least 500 Common Shares are traded in board lots) ending the second trading day before such date and the weighted average price shall be determined by dividing the aggregate sale price of all Common Shares sold in board lots on the exchange or market, as the case may be, during such 20 consecutive trading days by the number of Common Shares sold, or if not traded on any recognized market or exchange, as determined by the Directors acting reasonably;

• f. “ Definitive February 2024 Convertible Unsecured Debentures ” means the certificated (and also those represented by DRS Statement) February 2024 Convertible Unsecured Debentures fully registered in the names of the holders thereof;

• g. “ Director ” means a director of the Corporation for the time being, and, unless otherwise specified herein, reference to “action by the Directors” means action by the Directors of the Corporation as a board, or whenever duly empowered, action by any committee of such Board of Directors;

• h. “ DRS Statement ” means a statement evidencing a security-holding position under the direct registration system;

• i. “ Holder ” has the meaning ascribed thereto in Section 2(d);

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  - j. “ **Indenture** ” has the meaning ascribed thereto in the Recitals;

  - k. “ **Interest Payment Date** ” has the meaning ascribed thereto in Section 2(c);

  - l. “ **Issue Date** ” means the date on which the first February 2024 Convertible Unsecured Debenture is issued by the Corporation pursuant to this Second Supplemental Indenture;

  - m. “ **Maturity Date** ” has the meaning ascribed thereto in Section 2(b);

  - n. “ **Maturity Notice** ” means notice of maturity in the form attached as Schedule B to this Second Supplemental Indenture;

  - o. “ **February 2024 Convertible Unsecured Debentures** ” means $1,000 8% unsecured conditionally convertible debentures issued as part of the Offering with a maturity period of eighteen (18) months from the Issue Date, convertible into Common Shares at the Conversion Price;

  - p. “ **February 2024 Convertible Unsecured Debenture Offering** ” has the meaning ascribed thereto in the Recitals;

  - q. “ **Offering** ” means private placement pursuant to which the Corporation will issue up to 200 units, each of which is comprised of (i) $1,000 in principal amount of 8% unsecured convertible debentures, and (ii) 9,090 common share purchase warrants, up to an aggregate value of CAD$200,000;

  - r. “ **TSX** ” means Toronto Stock Exchange; and

  - s. “ **TSXV** ” means TSX Venture Exchange.

1. Creation of February 2024 Convertible Unsecured Debentures . The Corporation hereby creates for immediate issue pursuant to the Indenture and this Second Supplemental Indenture the 8% convertible unsecured debentures of the Corporation maturing on February 18, 2024 (each, an “ February 2024 Convertible Unsecured Debenture ”) on the following terms and conditions:

2. (a) The February 2024 Convertible Unsecured Debentures authorized for issue immediately are limited to an aggregate principal amount of up to CAD$200,000 at an issue price of $1,000 per February 2024 Convertible Unsecured Debenture and shall be designated as “8% Convertible Unsecured Debentures due February 18, 2024”, which consist of the February 2024 Convertible Unsecured Debentures offered in the Offering.

3. (b) Each February 2024 Convertible Unsecured Debenture shall be dated as of its date of issue and shall mature on February 18, 2024, regardless of its date of issue (the “ Maturity Date ”).

4. (c) The February 2024 Convertible Unsecured Debentures shall bear simple interest from and including their date of issue until the earlier of the Maturity Date and the Conversion Date at the rate of 8% per annum payable in equal instalments semi-annually on the 18[th] day of February and August of each year, in arrears, until the earlier of the Maturity Date and the Conversion Date, as applicable, (each, an “ Interest Payment Date ”), with interest payable after as well as before maturity and after as well as before default, with interest on amounts after maturity or default at the same rate. Notwithstanding the foregoing, for any February

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2024 Convertible Unsecured Debenture issued on or before February 10, 2023, the first such payment will fall due on February 18, 2023 and will represent interest payable from and including the date of issue of the applicable February 2024 Convertible Unsecured Debenture up to, but excluding, February 18, 2023, and the last such payment, for all February 2024 Convertible Unsecured Debentures, will fall due on the earlier of the Maturity Date and the Conversion Date, as applicable, and will represent accrued and unpaid interest payable from and including the last Interest Payment Date to, but excluding, the earlier of the Maturity Date and the Conversion Date, as applicable. Any payment required to be made on any day that is not a Business Day will be made on the next succeeding Business Day. The record dates for the payment of interest on the February 2024 Convertible Unsecured Debentures will be the fifth Business Day prior to the applicable Interest Payment Date.

• (d) The principal amount of the February 2024 Convertible Unsecured Debentures shall be convertible, in whole or in part (being $1,000 or integral multiples thereof), into Common Shares at any time on or after their date of issue and prior to the Maturity Date at the option of a Holder, at a conversion price of $0.11 per Common Share (the “ Conversion Price ”) and otherwise in the manner hereinafter provided and in accordance with and subject to the provisions hereinafter set forth. For greater certainty, accrued and unpaid interest may not be converted and shall be paid to the Holder (as defined below) at the time of conversion. No fractional share shall be issued upon conversion and the number of Common Shares to be issued on conversion shall be rounded down to the nearest whole number. Any amount of principal that could not be converted into a whole Common Share (“ Fractional Interest ”) shall be paid to the Holder in cash, which amount shall be calculated by multiplying the Fractional Interest by the Current Market Price, to be paid together with all accrued and unpaid interest thereon to the Conversion Date.

Notice of conversion in the form attached as Schedule A to the Debenture Certificate (a “ Conversion Notice ”), together with the related original Debenture Certificate(s) or the DRS Statement, shall be delivered to the Trustee (with a copy to the Corporation) by or on behalf of a holder of any February 2024 Convertible Unsecured Debentures (each, a “ Holder ”) setting out the amount of principal applicable to such Holder’s February 2024 Convertible Unsecured Debentures that it intends to convert and in the manner provided in Section 6.2 of the Indenture. The Conversion Notice, which shall be sent to the Toronto office of the Trustee, shall specify the distinguishing letters and numbers of the February 2024 Convertible Unsecured Debentures that are to be converted. The effective date of the conversion shall be the date on which the Trustee receives the Conversion Notice along with other documents required by the Trustee, assuming the register of the Trustee is open on such date (the " Conversion Date ") and the place of delivery to which the share certificate or DRS Statement representing the Common Shares of the Corporation into which such February 2024 Convertible Unsecured Debentures are to be converted is/are to be delivered.

Upon a Conversion Notice having been given as aforesaid, all the February 2024 Convertible Unsecured Debentures to be converted into Common Shares shall thereupon be and become converted into Common Shares on the Conversion Date specified in such Conversion Notice, in the same manner and with the same effect as if it were the date of maturity specified in such February 2024 Convertible Unsecured Debentures, anything therein or herein to the contrary notwithstanding. From and after such Conversion Date, if the Common Share certificate(s) or DRS Statement necessary to evidence conversion of such February 2024 Convertible Unsecured Debentures shall have been delivered to the

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Holder or otherwise duly registered in the applicable depository system by the Trustee as hereinafter provided and affidavits or other proof satisfactory to the Trustee as to the mailing of such notices shall have been lodged with it, such February 2024 Convertible Unsecured Debentures shall be deemed cancelled and no longer considered as outstanding hereunder and interest upon such converted February 2024 Convertible Unsecured Debentures shall cease to accrue after the Conversion Date.

Notwithstanding the above, any February 2024 Convertible Unsecured Debentures that remain outstanding at the Maturity Date may be repaid by the Corporation, at its sole and unfettered discretion, either with immediately available funds or by converting all of the remaining outstanding aggregate principal of the February 2024 Convertible Unsecured Debentures. In the event the Corporation desires to repay the outstanding February 2024 Convertible Unsecured Debentures at the Maturity Date by way of conversion, the Corporation shall deliver a Maturity Notice, mutatis mutandis , to the Trustee and the Holders not less than 10 days prior to the Maturity Date, and shall issue the applicable Common Shares to each Holder upon receipt and cancellation by the Trustee of each Holder’s original debenture certificate(s) representing the debentures to be converted. In the event of such conversion, the Corporation will deliver that number of Common Shares determined by dividing the Principal by 90% of the volume weighted average trading price of the Common Shares on the TSX for the five consecutive trading days immediately preceding (but not including) the Maturity Date. Such Common Shares will be issued as of Maturity Date, subject to the approval of the TSX.

Also in the event of such conversion, the Corporation will deliver to the Trustee:

• (a) an Officer’s Certificate setting forth the number of Common Shares to be delivered for each $1,000 principal amount of Debentures and the VWAP of the Common Shares on the TSX for the five consecutive trading days immediately preceding (but not including) the Maturity Date; and

• (b) an opinion of counsel to the effect that such Common Shares have been duly authorized and, when issued and delivered pursuant to the terms of this Indenture in payment of the principal amount of the Debentures outstanding will be validly issued as fully paid and non-assessable.

In case any question shall arise as to whether any Maturity Notice has been given as above provided, such question shall be decided by the Trustee whose decision shall be final and binding upon all parties interested.

All February 2024 Convertible Unsecured Debentures converted shall be cancelled by the Trustee and no February 2024 Convertible Unsecured Debentures shall be issued in substitution thereof, except in the event of a partial conversion of any of the February 2024 Convertible Unsecured Debentures, in which case, the Trustee shall issue a replacement February 2024 Convertible Unsecured Debenture representing the unconverted principal amount thereof. In the event of a partial conversion, all accrued and unpaid interest applicable to the unconverted principal of any February 2024 Convertible Unsecured Debenture shall remain accrued and shall continue to accrue in accordance with the provisions of this Second Supplemental Indenture.

• (e) For greater certainty, nothing in this Second Supplemental Indenture will in any manner restrict the Corporation from incurring, directly or indirectly, any additional indebtedness

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18010306.6

of any kind or rank and no consent or approval from the Holders or any Holder will be required. Each February 2024 Convertible Unsecured Debenture shall rank pari passu in right of payment of principal and of interest with all other February 2024 Convertible Unsecured Debentures.

• (f) The February 2024 Convertible Unsecured Debentures shall be issued in denominations of $1,000 and integral multiples of $1,000. Each February 2024 Convertible Unsecured Debenture and the certificate of the Trustee endorsed thereon shall be issued in substantially the form set out in Schedule “A” hereto with such insertions, omissions, substitutions or other variations as shall be required or permitted by this Second Supplemental Indenture, and may have imprinted or otherwise reproduced thereon such legend or legends or endorsements, not inconsistent with the provisions of this Second Supplemental Indenture, as may be required to comply with any law or with any rules or regulations pursuant thereto or with any rules or regulations of any securities exchange or securities regulatory authority or to conform with general usage, all as may be determined by the Board of Directors executing such February 2024 Convertible Unsecured Debentures in accordance with Section 2.7 of the Indenture, as conclusively evidenced by their execution of a February 2024 Convertible Unsecured Debenture. Each February 2024 Convertible Unsecured Debenture shall additionally bear such distinguishing letters and numbers as the Trustee shall approve. Notwithstanding the foregoing, a February 2024 Convertible Unsecured Debenture may be in such other form or forms as may, from time to time, be approved by a resolution of the Board of Directors, or as specified in an Officer’s Certificate.

The February 2024 Convertible Unsecured Debentures may be engraved, lithographed, printed, mimeographed or typewritten or partly in one form and partly in another.

The February 2024 Convertible Unsecured Debentures shall be issued in the form of one or more Definitive February 2024 Convertible Unsecured Debentures.

The Definitive February 2024 Convertible Unsecured Debentures will be registered in the names of each Holder thereof as provided in Section 3.1 of the Indenture. A Definitive February 2024 Convertible Unsecured Debenture may be exchanged, or transferred to and registered in the name of a person other than the registered holder thereof, as provided in Section 3.2 of the Indenture.

1. Legend . The certificates or other instruments representing the Common Shares, such as the DRS Statement, issuable upon conversion of the February 2024 Convertible Unsecured Debentures (and any replacement certificate or instrument issued prior to the expiration of the applicable hold periods), if issued prior to the expiration of the applicable hold periods affixed to the February 2024 Convertible Unsecured Debentures, will bear the following legend (or as otherwise required by the Corporation as per written order) in accordance with applicable securities legislation (the “ Legend ”):

“UNLESS PERMITTED UNDER SECURITIES LEGISLATION, THE HOLDER OF THIS SECURITY MUST NOT TRADE THE SECURITY BEFORE DECEMBER 19, 2022.

THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE LISTED ON THE TORONTO STOCK EXCHANGE ("TSX"); HOWEVER, THE SAID SECURITIES CANNOT BE TRADED THROUGH THE FACILITIES OF TSX SINCE THEY ARE NOT FREELY TRANSFERABLE, AND CONSEQUENTLY ANY CERTIFICATE REPRESENTING SUCH

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SECURITIES IS NOT "GOOD DELIVERY" IN SETTLEMENT OF TRANSACTIONS ON TSX.”

The Trustee and the Corporation will be entitled to request any other documents that may be required by the Corporation for the removal of the legends set forth above.

1. Waivers and Extensions : The Debentureholder may waive default or any breach by the Corporation of any of the provisions contained in this Debenture, solely relating to the Debenture or Debentures held by that Debentureholder only. No waiver extends to a subsequent breach or default, whether or not such subsequent breach or default is the same as or similar to the breach or default waived, and no act or omission of the Debentureholder extends to or is be taken in any manner to affect any subsequent breach or default of the Corporation or the rights of the Debentureholder resulting therefrom. Any such waiver must be in writing and signed by the Debentureholder to be effective.

2. Currency . Unless otherwise indicated, all payments to be made under this Second Supplemental Indenture will be made in Canadian dollars.

3. Headings . The headings in this Second Supplemental Indenture are inserted for convenience of reference only and shall not affect the construction or interpretation of this Second Supplemental Indenture.

4. Indenture Remains in Effect. Except as expressly modified by this Second Supplemental Indenture, the terms and conditions of the Indenture and the other supplemental indentures remain in full force and effect and are hereby ratified by the parties in all respects. Unless explicitly amended by this Second Supplemental Indenture, no term, condition, covenant, liability or obligation contained in the Indenture is otherwise amended, varied or modified by this Second Supplemental Indenture. The February 2024 Convertible Unsecured Debentures will be deemed to be an ‘Additional Debenture’ for all purposes under the Indenture.

5. Entire Agreement. This Second Supplemental Indenture, together with the Indenture, constitute the entire agreement among the parties and supersedes all prior agreements, representations, warranties, conditions, statements, promises, information, arrangements and understandings, whether written or oral, express or implied, statutory or otherwise, with respect to the subject matter hereof. This Second Supplemental Indenture may not be amended or modified in any respect except by written instrument signed by the parties hereto and with the approval of Holders holding at least a majority of the then-outstanding principal amount of February 2024 Convertible Unsecured Debentures.

6. Governing Law . This Second Supplemental Indenture, for all purposes, shall be governed by and construed in accordance with the laws of the Province of Ontario and the federal laws of Canada applicable therein.

7. Counterparts . This Second Supplemental Indenture may be executed by hand or by duly authorized application of an electronic signature in one or more counterparts, each of which when so executed and delivered shall be an original, and such counterparts shall together constitute one and the same instrument. An executed counterpart of this Second Supplemental Indenture may be delivered by facsimile transmission or emailed.

8. [ Signature page follows ]

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18010306.6

DocuSign Envelope ID: 9EFFE87F-8633-4DC0-A0CC-98AE5A6DA322

IN WITNESS WHEREOF the parties have executed this Second Supplemental Indenture as of the date first written above.

STAGEZERO LIFE SCIENCES LTD.

By: “ James Howard-Tripp ” Name: Title: Chief Executive Officer

TSX TRUST COMPANY

“ Sumit Khanna ”

By: Name: Sumit Khanna Title: Corporate Trust Officer

“ Donald Crawford ” By: Name: Donald Crawford Title: Senior Trust Officer

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18010306.6

SCHEDULE “A” FORM OF FEBRUARY 2024 CONVERTIBLE UNSECURED DEBENTURE

UNLESS PERMITTED UNDER SECURITIES LEGISLATION, THE HOLDER OF THIS SECURITY MUST NOT TRADE THE SECURITY BEFORE DECEMBER 19, 2022.

THE SECURITIES REPRESENTED HEREBY AND THE SECURITIES ISSUABLE UPON CONVERSION HEREOF HAVE NOT BEEN AND WILL NOT BE REGISTERED UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE “U.S. SECURITIES ACT”), OR UNDER ANY STATE SECURITIES LAWS, AND MAY BE OFFERED, SOLD, PLEDGED OR OTHERWISE TRANSFERRED ONLY (A) TO STAGEZERO LIFE SCIENCES LTD. (THE “CORPORATION”), (B) OUTSIDE THE UNITED STATES IN ACCORDANCE WITH RULE 904 OF REGULATION S UNDER THE U.S. SECURITIES ACT AND IN COMPLIANCE WITH APPLICABLE LOCAL LAWS AND REGULATIONS, (C) PURSUANT TO THE EXEMPTION FROM REGISTRATION UNDER THE U.S. SECURITIES ACT PROVIDED BY RULE 144 UNDER THE U.S. SECURITIES ACT, IF AVAILABLE, AND IN COMPLIANCE WITH APPLICABLE U.S. STATE SECURITIES LAWS, (D) IN COMPLIANCE WITH ANOTHER EXEMPTION FROM REGISTRATION UNDER THE U.S. SECURITIES ACT AND APPLICABLE STATE SECURITIES LAWS, OR (E) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE U.S. SECURITIES ACT; PROVIDED THAT IN THE CASE OF TRANSFERS PURSUANT TO (C) OR (D) ABOVE, A LEGAL OPINION REASONABLY SATISFACTORY TO THE CORPORATION MUST FIRST BE PROVIDED TO THE CORPORATION AND ITS REGISTRAR AND TRANSFER AGENT TO THE EFFECT THAT SUCH TRANSFER IS EXEMPT FROM REGISTRATION UNDER THE U.S. SECURITIES ACT AND APPLICABLE STATE SECURITIES LAWS. DELIVERY OF THIS CERTIFICATE MAY NOT CONSTITUTE “GOOD DELIVERY” IN SETTLEMENT OF TRANSACTIONS ON STOCK EXCHANGES IN CANADA.

STAGEZERO LIFE SCIENCES LTD.

(a corporation incorporated under the laws of Ontario)

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Convertible Debenture

				Convertible Debenture
Debenture #: [*]
Issue Date: August 18, 2022 (the “Issue Date”)
Issuer: StageZero Life Sciences Ltd.(the “Company”)
70		East Beaver Creek Road
Unit 30
Richmond Hill, Ontario
L4B 3B2
Attention:	James R Howard-Tripp, Chairman and CEO
Maturity: February 18, 2024 (the “Maturity Date”)
Holder: <*>			(the “Debentureholder”)
Principal: $<*>				CAD (the “Principal”)
Interest: Eight percent (8%) per annum simple interest with interest to be paid in arrears
semi-annually from the Issue Date (each, an “Interest Payment Date”), in each
case in an amount equal to the interest that has accrued from the last applicable
Interest Payment Date until the calendar day before the Interest Payment Date or
Maturity Date (as the case may be). Notwithstanding the foregoing, on the first
Interest Payment Date, which shall be February 18, 2023, the interest payment shall
be		for interest accrued between the Issue Date and February 18, 2023. Interest will
be		paid in cash.
Definitions: All defined terms used in this Debenture that are not otherwise defined herein shall
have				the meaning ascribed thereto in the Indenture.

WHEREAS the Debentureholder has advanced to the Company an amount equal to the Principal in connection with a private placement offering of up to an aggregate CAD$200,000 principal amount of 8% convertible unsecured debentures (the “ Debentures ”) undertaken by the Company;

AND WHEREAS the Company is now indebted to the Debentureholder in an amount equal to the Principal together with interest thereon as herein set forth;

NOW THEREFORE THIS DEBENTURE WITNESSETH THAT:

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ARTICLE 1 TERMS

1.1 Issue

The Company, a corporation amalgamated under the laws of Ontario and having its registered office at the address shown above, for value received, acknowledges itself indebted and promises to pay to or to the order of the Debentureholder on the dates specified herein, at the main branch of TSX Trust Company (the “ Trustee ”) in Toronto, Ontario in accordance with the terms of the Indenture (as defined in Section 1.2), the Principal and to pay interest (the “ Interest ”) on the outstanding Principal at the Annualized Rate (as defined in Section 1.3), all in accordance with the terms of the Indenture. Interest on the outstanding Principal over the Term (as defined in Section 1.5) is calculated in respect of the Term from the Issue Date.

1.2 Indenture

This Debenture Certificate represents Debentures issued under the provisions of an indenture dated December 23, 2016 between the Company and the Trustee (which indenture together with all other instruments supplemental or ancillary thereto, including the Second Supplemental Indenture between the Company and the Trustee dated August 18, 2022, are all referred to herein as the “ Indenture ”), which Indenture contains particulars of the rights of the holders of the Debentures and the Company and of the Trustee in respect thereof and the terms and conditions upon which the Debentures are issued and held, all to the same effect as if the provisions of the Indenture were herein set forth, to all of which the holder of this Debenture Certificate by acceptance hereof assents. A copy of the Indenture is available for inspection on the Company’s profile on www.sedar.com or the Company shall, on the written request of the Debentureholder and without charge, provide the Debentureholder with a copy of the Indenture. In the event of any inconsistency between the provisions of the Indenture (and any amendments thereto and instruments supplemental thereto) and the provisions of this Debenture Certificate, the provisions of the Indenture shall prevail.

The indebtedness evidenced by this Debenture is a direct obligation of the Company, and is subordinated in right of payment to the extent and in the manner provided in the Indenture, to the prior payment in full of all Senior Indebtedness (as such term is defined in the Indenture), whether outstanding as at the date of the Indenture or thereafter created, incurred, assumed or guaranteed.

This Debenture shall not become obligatory for any purpose until it shall have been certified by the Trustee under the Indenture.

1.3 Annualized Rate

The annualized interest rate applicable under this Debenture prior to the Maturity Date, default or judgement will be eight percent (8%) simple interest per annum (the “ Annualized Rate ”). From and after the Maturity Date, default or judgment, to the extent the Principal or a portion of it is outstanding, it shall continue to be payable at the Annualized Rate and shall be calculated on the portion of the Principal that remains unpaid, until fully paid, on the basis that the actual number of days for which the Principal is outstanding is computed on the basis of 365 days, or 366 days in the case of a leap year.

1.4 Interest Payments

Subject to Section 1.5, the Company will pay all Interest payable throughout the Term of this Debenture on the applicable Interest Payment Date. From and after the Maturity Date, default or judgment, to the extent the Principal or a portion of it is outstanding, Interest at the Annualized Rate shall be deemed earned, due and payable on a quarterly basis in arrears. Interest will be paid in cash.

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1.5 Term

The term (the “ Term ”) of this Debenture shall be for the period commencing on the Issue Date and ending on the Maturity Date. Subject to (a) acceleration following an Event of Default (as defined in the Indenture) hereunder by the Company in accordance with the terms herein, or (b) the Debentureholder’s right to convert this Debenture in accordance with Section 1.8 below, this Debenture (as to any and all outstanding Principal and Interest) shall be repaid in full by the Company to the Debentureholder at the end of the Term on the Maturity Date.

1.6 Principal Payment

On the Maturity Date, the Principal will be paid in cash or in Common Shares of the Company at the sole discretion of the Company, subject to any required approval of the Toronto Stock Exchange (or any successor exchange) (the “ TSX ”) and the provisions of the Indenture. If the Company elects to pay the Principal in Common Shares, the Company will deliver that number of Common Shares determined by dividing the Principal by 90% of the volume weighted average trading price of the Common Shares on the TSX for the five consecutive trading days immediately preceding (but not including) the Maturity Date. Such Common Shares will be issued as of the Maturity Date, subject to the approval of the TSX.

1.7 [Intentionally Deleted]

1.8 Conversion at the Option of the Debentureholder

The Conversion Amount also shall be convertible at the option of the Debentureholder into Common Shares at any time from Issue Date. Should the Debentureholder wish to convert the Conversion Amount, the Debentureholder must provide notice to the Company by delivery of an executed copy of a notice of conversion substantially in the form attached hereto as Schedule “A” (the “ Conversion Notice ”), in accordance with the terms of the Indenture.

The Conversion Amount shall be converted into Common Shares at a price of $0.11 per Common Share.

None of the Debentures may be converted in the “United States” or by or for the benefit of a “U.S. person” (as such terms are defined in Regulation S under the United States Securities Act of 1933, as amended (the “ U.S. Securities Act ”)) unless the Debentureholder has: (i) certified to the Company and its transfer agent, in a form reasonably satisfactory to the Company, that it is not, and is not converting the Debentures for the account or benefit of any person that is, a U.S. person or in the United States, or (ii) delivered to the Company an Accredited Investor Certificate in the form attached as Exhibit 1 to the Conversion Notice; or (iii) delivered to the Company a written opinion of counsel to the effect that such conversion is not subject to or is exempt from the registration requirements of the U.S. Securities Act and applicable state securities or “blue sky” laws, which opinion and counsel shall be reasonably satisfactory to the Company.

1.9 No Fractional Securities

The Company shall not issue any fraction of a Common Shares upon a conversion of Debentures pursuant to Section 1.8 or the Principal Payment pursuant to Section 1.6 and fractional entitlements shall be subject to the terms of the Indenture.

1.10 Covenants

The Company covenants with the Debentureholder that:

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• (a) It will reserve and keep available a sufficient number of unissued Common Shares to satisfy its obligations upon conversion of this Debenture and upon a Principal Repayment.

• (b) Common Shares issued pursuant to Sections 1.6 or 1.8 shall be validly issued as fully paid and non-assessable shares.

• (c) Intentionally deleted.

ARTICLE 2 DEFAULT AND REMEDIES

2.1 Default

The obligations to pay the Principal and Interest due and payable hereunder are immediately due, and all rights and remedies hereby conferred shall become immediately enforceable, in the event of an Event of Default (as such term is defined in the Indenture).

2.2 Covenant

The Company covenants that, so long as any Principal or Interest is outstanding under this Debenture, subject to applicable securities laws, the Company will advise the Debentureholder, in reasonable detail, of the occurrence of any Event of Default.

2.3 Waivers and Extensions

The Debentureholder may waive default or any breach by the Company of any of the provisions contained in this Debenture, solely relating to the Debenture or Debentures held by that Debentureholder only. No waiver extends to a subsequent breach or default, whether or not such subsequent breach or default is the same as or similar to the breach or default waived, and no act or omission of the Debentureholder extends to or is be taken in any manner to affect any subsequent breach or default of the Company or the rights of the Debentureholder resulting therefrom. Any such waiver must be in writing and signed by the Debentureholder to be effective.

ARTICLE 3 ASSIGNABILITY

3.1 Assignability

The Company may not assign its rights in and under this Debenture. The Debentureholder may sell, transfer or assign its rights in and under this Debenture, in whole or in part, without the express prior written consent of the Company and provided such sale, transfer or assignment is in compliance with the Indenture and all applicable securities and corporate laws, rules, regulations, instruments, notices, blanket orders, statements, circulars, procedures and policies in Ontario or, where applicable, any other jurisdiction where the transferee resides.

ARTICLE 4 GENERAL

4.1 Notice

Any notice, consent or approval required or permitted to be given in connection with this Debenture, including the Maturity Notice, must be given in accordance with the Indenture.

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4.2 Enurement

This Debenture enures to the benefit of the Debentureholder and its successors and permitted assigns, and is binding upon the Company and its successors.

4.3 Governing Law

This Debenture is made under and governed by and is to be construed in accordance with the laws of the Province of Ontario and the federal laws of Canada applicable in the Province of Ontario. Each of the Company and the Debentureholder irrevocably attorns to the jurisdiction of the courts of the Province of Ontario with respect to any matters arising out of this Debenture.

4.4 Immunity of Shareholders, Officers and Directors

No recourse under or upon any obligation, covenant or agreement of this Debenture, or for any claim based thereon or otherwise in respect thereof, shall be had against any shareholder, officer or director, as such, past, present or future of the Company, either directly or through the Company, whether by virtue of any constitution, statute or rule of law, or by the enforcement of any assessment or penalty or otherwise; it being expressly understood that this Debenture is solely a corporate obligation, and that no such personal liability whatsoever shall attach to, or is or shall be incurred by shareholders, officers or directors, as such, of the Company or any of them because of the creation of the indebtedness hereby evidenced, or under or by reason of the obligations, covenants or agreements contained in this Debenture, and that any and all such personal liability, either at common law or in equity or by constitution or statute, and any and all such rights and claims against every such shareholder, officer or director, as such, because of the creation of the indebtedness hereby authorized, or under or by reason of the obligations, covenants or agreements contained in this Debenture or implied therefrom, are hereby expressly waived and released as a condition of, and as a consideration for, the execution and issuance of this Debenture.

4.5 Debenture Lost or Stolen

If this Debenture is mutilated, lost, stolen or destroyed, the Company shall, upon being furnished with evidence satisfactory to it of such mutilation, loss, theft or destruction and such indemnity to Company and to the Trustee or other documentation required by the Company, issue and deliver a new Debenture of like date and tenor as the one mutilated, lost, stolen or destroyed, in exchange for, in place of and upon cancellation of the mutilated Debenture, or in lieu of or in substitution for the lost, stolen or destroyed Debenture.

4.6 No Merger or Novation

Neither the taking of any judgment nor the exercise of any power of seizure or sale shall operate to extinguish the liability of the Company to pay the indebtedness nor shall the same operate as a merger of any covenant herein contained or of any other obligation, nor shall the acceptance of any payment or security constitute or create any novation.

4.7 Amendments, etc. to the Debentures

The terms and conditions of the Debentures may be modified, amended or waived in accordance with the terms of the Indenture. All Debentureholders shall be bound by any such modification, amendment or waiver granted in accordance therewith, whether or not they participated in the meeting and/or executed the agreement or written resolution.

• [ Remainder of page intentionally left blank. Signature page follows .]

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DocuSign Envelope ID: 9EFFE87F-8633-4DC0-A0CC-98AE5A6DA322

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IN WITNESS WHEREOF the Company has caused this Debenture to be signed by a duly authorized officer of the Company as of the Issue Date.

STAGEZERO LIFE SCIENCES LTD.

By: ___ James R Howard-Tripp Chairman and CEO

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(FORM OF TRUSTEE CERTIFICATE)

This Debenture is one of the 8% convertible unsecured debentures due February 18, 2024 referred to in the Indenture within mentioned.

TSX TRUST COMPANY

By: ______

Authorized Officer

SCHEDULE “ A” to DEBENTURE CONVERSION NOTICE

To: STAGEZERO LIFE SCIENCES LTD. 70 East Beaver Creek Road, Unit 30 Richmond Hill, Ontario, L4B 3B2

And To: TSX TRUST COMPANY 301-100 Adelaide Street West Toronto, Ontario M5H 4H1 Attn: Corporate Actions

Note: All capitalized terms used herein have the meaning ascribed thereto in the Indenture mentioned below, unless otherwise indicated.

StageZero Life Sciences Ltd. issued the attached Debenture to the holder stated therein. The undersigned registered holder of 8% Convertible Unsecured Debentures irrevocably elects to convert the Conversion Amount of such Debentures in accordance with the terms of the Indenture referred to in such Debentures and tenders herewith the Debentures, and, if applicable, directs that the certificates representing the common shares of StageZero Life Sciences Ltd. (“ Common Shares ”) issuable upon a conversion be issued and delivered to the person indicated below. (If any Common Shares are to be issued in the name of a person other than the holder, all requisite transfer taxes must be tendered by the undersigned).

Dated:

(Signature of Registered Holder)

• If less than the full principal amount of the Debentures, indicate in the space provided the principal amount (which must be $1,000 or integral multiples thereof) to be converted.

Conversion Amount: $

NOTE If Common Shares are to be issued in the name of a person other than the holder, the signature must be guaranteed by a chartered bank, a trust company or by a member of an acceptable Medallion Guarantee Program. The Guarantor must affix a stamp bearing the actual words: “SIGNATURE GUARANTEED”.

(Print name in which the Common Shares are to be issued, delivered and registered)

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Name:

(Address)

(City, Province and Postal Code)

Name of guarantor:

Authorized signature:

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Exhibit 1 to the Conversion Notice US Accredited Investor Certificate (for use by US resident Debentureholders)

TO: STAGEZERO LIFE SCIENCES LTD. (the “Company”)

In connection with the conversion by the Subscriber of the Debentures for the Common Shares, the Subscriber, on its own behalf and on behalf of each Beneficial Purchaser for whom the undersigned is acting (collectively, the “ Subscriber ”), hereby represents, warrants, covenants and certifies to the Company (and acknowledges that the Company and its counsel are relying thereon) that that the Subscriber is an “accredited investor”, as that term is defined in Rule 501(a) under the U.S. Securities Act of 1933, as amended (the “U.S. Securities Act”), because the Subscriber is (check each applicable category):

Category 1. A bank, as defined in Section 3(a)(2) of the U.S. Securities Act, whether acting in its individual or fiduciary capacity; or [Rule 501(a)(1)] Category 2. A savings and loan association or other institution as defined in Section 3(a)(5)(A) of the U.S. Securities Act, whether acting in its individual or fiduciary [Rule 501(a)(1)] capacity; or Category 3. A broker or dealer registered pursuant to Section 15 of the U.S. Securities Exchange Act of 1934, as amended; or [Rule 501(a)(1)] Category 4. An investment adviser registered pursuant to Section 203 of the U.S. Investment Advisers Act of 1940, as amended, or registered pursuant to the laws of a state; [Rule 501(a)(1)] or Category 5. An investment adviser relying on the exemption from registering with the Commission under Section 203(l) or (m) of the U.S. Investment Advisers Act of [Rule 501(a)(1)] 1940, as amended; or Category 6. An insurance company as defined in Section 2(a)(13) of the U.S. Securities Act; or [Rule 501(a)(1)] Category 7. An investment company registered under the U.S. Investment Company Act of 1940, as amended; or [Rule 501(a)(1)] Category 8. A business development company as defined in Section 2(a)(48) of the U.S. Investment Company Act of 1940, as amended; or [Rule 501(a)(1)] Category 9. A Small Business Investment Company licensed by the U.S. Small Business Administration under Section 301(c) or (d) of the U.S. Small Business Investment [Rule 501(a)(1)] Act of 1958, as amended; or Category 10. A Rural Business Investment Company as defined in Section 384A of the U.S. Consolidated Farm and Rural Development Act of 1972, as amended; or [Rule 501(a)(1)]

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Category 11.

[Rule 501(a)(1)] Category 12.

[Rule 501(a)(1)]

Category 13.

A plan established and maintained by a state, its political subdivision or any agency or instrumentality of a state or its political subdivisions, for the benefit of its employees, with assets in excess of U.S. $5,000,000; or

An employee benefit plan within the meaning of the U.S. Employee Retirement Income Security Act of 1974, as amended , in which the investment decision is made by a plan fiduciary, as defined in Section 3(21) of such act, which is either a bank, savings and loan association, insurance company or registered investment advisor, or an employee benefit plan with total assets in excess of U.S. $5,000,000 or, if a self-directed plan, the investment decisions are made solely by persons who are accredited investors; or

A private business development company as defined in Section 202(a)(22) of the U.S. Investment Advisers Act of 1940, as amended; or

[Rule 501(a)(2)]

Category 14.

[Rule 501(a)(3)]

Category 15. [Rule 501(a)(4)] Category 16.

An organization described in Section 501(c)(3) of the U.S. Internal Revenue Code of 1986, as amended, a corporation, a Massachusetts or similar business trust, a partnership, or a limited liability company, not formed for the specific purpose of acquiring the securities offered, with total assets in excess of U.S. $5,000,000; or

A director, executive officer or general partner of the issuer of the securities being offered or sold, or any director, executive officer, or general partner of a general partner of that issuer; or

A natural person whose individual net worth, or joint net worth with that person’s spouse or spousal equivalent, exceeds U.S. $1,000,000; or

[Rule 501(a)(5)]

( Note : For the purposes of calculating “net worth”

• (i) the person’s primary residence shall not be included as an asset;

• (ii) indebtedness that is secured by the person’s primary residence, up to the estimated fair market value of the primary residence at the time of the closing of the Offering, shall not be included as a liability (except that if the amount of such indebtedness outstanding at the time of the closing of the Offering exceeds the amount outstanding 60 days before such time, other than as a result of the acquisition of the primary residence, the amount of such excess shall be included as a liability); and

• (iii) indebtedness that is secured by the person’s primary residence in excess of the estimated fair market value of the primary residence shall be included as a liability.)

( Note : For the purposes of calculating “joint net worth”, joint net worth can be the aggregate net worth of the investor and spouse or spousal equivalent, and assets need not be held jointly to be included in the calculation. Reliance on the joint net worth standard does not require that the securities be purchased jointly.)

( Note : The term “spousal equivalent” means a cohabitant occupying a relationship generally equivalent to that of a spouse.)

• 5 -

Category 17. A natural person who had an individual income in excess of U.S. $200,000 in each year of the two most recent years or joint income with that person’s spouse [Rule 501(a)(6)] or spousal equivalent in excess of U.S. $300,000 in each of those years and has a reasonable expectation of reaching the same income level in the current year; or

( Note : The term “spousal equivalent” means a cohabitant occupying a relationship generally equivalent to that of a spouse.)

Category 18. A trust, with total assets in excess of U.S. $5,000,000, not formed for the specific purpose of acquiring the securities offered, whose purchase is directed by a [Rule 501(a)(7)] sophisticated person as described in Rule 506(b)(2)(ii) under Regulation D under the U.S. Securities Act; or

Category 19.

An entity in which each of the equity owners are accredited investors; or

• [Rule 501(a)(8)] ( Note: It is permissible to look through various forms of equity ownership to natural persons in determining the accredited investor status of entities under this category. If those natural persons are themselves accredited investors, and if all other equity owners of the entity seeking accredited investor status are accredited investors, then this category may be available.)

Category 20. An entity, of a type not listed in Categories 1 through 14, 18 or 19 above, not formed for the specific purpose of acquiring the securities offered, owning [Rule 501(a)(9)] “investments” (as defined in Rule 2a51-1(b) under the U.S. Investment Company Act of 1940, as amended) in excess of U.S. $5,000,000; or

• Category 21.

• [Rule 501(a)(10)]

A natural person holding in good standing one or more of the following professional licenses:

• (i) General Securities Representative license (Series 7);

• (ii) Private Securities Offerings Representative license (Series 82), and

• (iii) Investment Adviser Representative license (Series 65); or

Category 22. A natural person who is a “knowledgeable employee” (as defined in Rule 3c5(a)(4) under the U.S. Investment Company Act of 1940, as amended) of the [Rule issuer of the securities being offered or sold where the issuer would be an 501(a)(11)] “investment company” (as defined in Section 3 of U.S. Investment Company Act of 1940, as amended), but for the exclusion provided by either Section 3(c)(1) or section 3(c)(7) of U.S. Investment Company Act of 1940, as amended; or

Category 23. A “family office” (as defined in Rule 202(a)(11)(G)-1 under the U.S. Investment Advisers Act of 1940, as amended):

• [Rule 501(a)(12)]

• (i) with assets under management in excess of U.S. $5,000,000,

• (ii) that is not formed for the specific purpose of acquiring the securities offered, and

• (iii) whose prospective investment is directed by a person who has such knowledge and experience in financial and business matters that such family office is capable of evaluating the merits and risks of the prospective investment; or

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Category 24. A “family client” (as defined in Rule 202(a)(11)(G)-1 under the U.S. Investment Advisers Act of 1940, as amended) of a family office meeting the requirements [Rule in Category 23 above and whose prospective investment in the issuer is directed 501(a)(13)] by such family office pursuant to clause (iii) of Category 23.

Dated at _ this _ day of _____.

Name of Subscriber

Signature

If the Subscriber is a corporation, office or title of signatory

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SCHEDULE “B” MATURITY NOTICE

To: Holders of 8% Convertible Unsecured Debentures (the “ Debentures ”) of StageZero Life Sciences Ltd. (the “ Corporation ”)

And To: TSX Trust Company (the “ Trustee ”), in addition to the Holders 301-100 Adelaide Street West Toronto, Ontario M5H 4H1 Attn: Corporate Actions

Note: All capitalized terms used herein have the meaning ascribed thereto in the Indenture mentioned below, unless otherwise indicated.

Notice is hereby given pursuant to the debenture indenture dated as of December 23, 2016 among the Corporation and the Trustee, as amended and supplemented by the Second Supplemental Indenture between the Corporation and the Trustee dated August 18, 2022 (together, the “ Indenture ”), that the Debentures are due and payable as of February 18, 2024 (the “ Maturity Date ”) and the Corporation hereby irrevocably elects to satisfy its obligation to pay $<> of the principal amount of this Debenture due on the Maturity Date, by the issue of that number of common shares of the Corporation (“ Common Shares* ”) obtained by dividing the principal amount of this Debenture by 90% of the VWAP of the Common Shares for the 5 consecutive trading days ending on the trading day immediately preceding the date the principal amount is due, subject to the approval of the Toronto Stock Exchange. All accrued and unpaid interest on the Debentures up to the Maturity Date will be paid in cash.

No fractional Common Shares shall be delivered on exercise by the Corporation of the above mentioned repayment right but, in lieu thereof, the Corporation shall pay the cash equivalent thereof determined on the basis of 90% of the VWAP of the Common Shares for the 5 consecutive trading days ending on the trading day immediately preceding the Maturity Date (less any tax required to be deducted, if any).

In this connection, upon presentation and surrender of the Debentures for payment on the Maturity Date, the Corporation shall, subject to the approval of the Toronto Stock Exchange, on the Maturity Date, make delivery to the Trustee, at its principal trust office in Toronto, Ontario, for delivery to and on account of the holders, of certificates representing the Common Shares to which holders are entitled together with the cash equivalent in lieu of fractional Common Shares, and if only a portion of the Debentures are to be repaid by issuing Common Shares, cash representing the balance of the principal amount and interest due on the Maturity Date.

[ Signature page follows ]

C-2

DATED: <*>

STAGEZERO LIFE SCIENCES LTD.

By:

(Authorized Director or Officer of StageZero Life Sciences Ltd.)