ABIVAX Societe Anonyme : announces the pricing of its oversubscribed capital increase of EUR 60M and convertible bonds of EUR 25M, totaling EUR 85M new financing

ABIVAX ANNOUNCES THE PRICING OF ITS OVERSUBSCRIBED CAPITAL INCREASE OF EUR 60 M AND CONVERTIBLE BONDS OF EUR 25 M, TOTALING EUR 85M NEW FINANCING

EUR 60M reserved primary equity offering at minimum discount (3%)

EUR 25M convertible bonds priced at 6.00% coupon and 25% conversion premium

Proceeds to be primarily used for further advancement of ABX464 clinical programs in chronic

inflammatory diseases, expanding the cash runway into Q2 2022

PARIS, FRANCE, July 23, 2021 - 8.00 a.m. (CEST) - Abivax (Euronext Paris: FR0012333284 - ABVX) (the "Company"), a clinical-stage biotechnology company harnessing the immune system to develop novel treatments for inflammatory diseases, viral diseases and cancer, today announces the successful completion of a reserved oversubscribed capital increase (the "Capital Increase") of approximately EUR 60M through the issuance of 1,964,031 shares with a nominal value of EUR 0.01 each (the "New Shares"), representing 13.34% of its current share capital, at a subscription price of EUR 30.55 per share, and the placement of senior, unsecured bonds convertible into new shares and/or exchangeable for existing shares (obligations convertibles échangeables en actions nouvelles ou existantes - OCEANE) (the "Bonds") maturing in July 30, 2026 in aggregate principal amount of EUR 25M (the "Transaction").

Reasons for the issuance and use of the net proceeds of the Transaction, equal to EUR 82M

• Launch and continuation of the clinical programs of ABX 464, the Company's lead product in advanced development for a large majority of the proceeds, for around 75% of the proceeds:
• • continuation of the phase 2a and phase 2b maintenance studies conducted with ABX464 in patients with moderate to severe ulcerative colitis (UC) and planned initiation of a global pivotal phase 3 program of ABX464 for the treatment of UC by year end;
  • planned initiation of a pivotal phase 2b clinical program of ABX464 for the treatment of Crohn's disease
    (CD) by year end;
  • planned initiation of a phase 2b clinical program of ABX464 for the treatment of RA in Q1 2022;
  • continuation of the phase 2a maintenance study conducted with ABX464 in patients with moderate to severe rheumatoid arthritis (RA);
  • continuation of the R&D work on ABX464;
• Financing of R&D and working capital and other general purposes of the Company, for around 15% of the proceeds;
• Redemption of (and payment of amounts payable pursuant to) existing indebtedness, for around 8% of the proceeds;
• Advancement of the phase 1/2 proof-of-concept clinical trial of ABX196 for the treatment of hepatocellular carcinoma, for around 2% of the proceeds.

The Company expects that the proceeds from the Transaction will provide the Company with financial resources (cash runway) to fund its operations into Q2 2022, based on ongoing programs.

Based on its current development plans, the Company estimates that the cash and cash equivalents available to it as at June 30, 2021, i.e. EUR 4.3M, together with the financial resources available to it in the short term (listed below) allow it to finance its cash needs into Q4 2021.

1. Remainder of the Kepler Cheuvreux equity line (estimated at EUR 9.7M based on an EUR 30 share price)

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1. Receivable against Bpifrance in connection corresponding to the remainder of the financing of the ABX464 Covid-19 program (estimated at EUR 3.1M)

1. Upcoming reimbursement of the R&D tax credit (Crédit Impôt Recherche) for 2020 (estimated at EUR 2.6M)

The Company's cash expenditures as from Q4 2021 and for the first half of 2022 will amount to at least EUR 30M per quarter in light of the launch timetable of the Company's strategic clinical trials for ABX464 (phase 3 in UC, phase 2b in Crohn, and phase 2b in RA), which is planned between Q4 2021 and Q1 2022.

The additional cash needs of the Company (prior to the Transaction) for the upcoming 12 month period amount to EUR 100M, i.e. EUR 18M in addition to the proceeds of the Transaction.

The completion by the Company of a strategic partnership with an industry player and/or of complementary dilutive or non-dilutive financings (the modalities of which will be determined based on prevailing market conditions) could allow the Company to cover its additional EUR 18M cash need. In the absence of such financing, the Company could also envisage to adapt the launch timetable of the clinical trials for ABX464.

Prof. Hartmut J. Ehrlich, M.D., CEO of Abivax said: "We are pleased with the successful completion of Abivax's oversubscribed capital increase at a tight 3% discount, along with the placement of convertible bonds that jointly amount to EUR 85M.With these financial resources, we will pursue the Company's strategic priorities and initiate our late-stage global clinical program of ABX464 for the treatment of ulcerative colitis and Crohn's disease by year end. Following the latest very positive results of ABX464 for the treatment of rheumatoid arthritis, we are additionally preparing for a phase 2b clinical study in RA, which is expected to start beginning of 2022. We observe a continued high need of novel therapeutic management options that offer a constant and long-lasting improvement of the quality of life of patients suffering from chronic inflammatory diseases. Abivax's ambition is to fully exploit the anti-inflammatory potential of our lead compound ABX464 across different indications for the benefit of these patients."

Didier Blondel, CFO of Abivax, added: "We are pleased that Abivax could attract top-tier U.S. and European biotech investors, led by Vivo Capital, Sofinnova, Invus and Commodore Capital. This is another valuable recognition of the remarkable clinical achievements with ABX464 during the past months and years. This successful financing round with favorable conditions puts Abivax on solid ground to go full steam to launch the late-stage clinical testing of ABX464 in inflammatory bowel diseases and rheumatoid arthritis. Based on our current assumptions, our cash runway has been extended into Q2 2022. We will make targeted use of these financial resources in order to eventually offer novel and efficient therapeutic options to patients and maximize shareholder value. This includes the continued assessment of a strategic partnership with a large pharma or biotech company, that would consider the entire potential of ABX464 in chronic inflammatory indications."

Key characteristics of the transaction

Bonds Convertible into New Shares and/or Exchangeable for Existing Shares

The Bonds will be issued at par and bear an interest of 6.00% per annum payable semi-annually in arrears on 30 January and 30 July each year, commencing on 30 January 2022.

The nominal value of the Bonds has been set at EUR 38.19, corresponding to a premium of 25% above the reference share price, which has been set as the clearing price of the concurrent Capital Increase.

Bondholders will be granted a conversion/exchange right of the Bonds into new and/or existing shares of the Company (the "Conversion/Exchange Right") which they may exercise at any time from the Issue Date and until the 7th trading day (inclusive) preceding the Maturity Date or the relevant early redemption date.

The initial conversion/exchange ratio is set at one share per Bond (i.e. a conversion price of EUR 38.19 per ordinary share).

The conversion/exchange ratio will be adjusted (but only if the conversion/exchange ratio so adjusted is higher than the conversion/exchange ratio that would reset) on each of January 30, 2023, July 30, 2023, and July 30, 2024 as further defined in the terms and conditions of the Bonds.

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The conversion/exchange ratio is also subject to standard adjustments, including anti-dilution and dividend protections, as detailed in the terms and conditions of the Bonds. Upon exercise of their Conversion/Exchange Right, bondholders will receive at the option of the Company new and/or existing Company's shares carrying in all cases all rights attached to existing shares as from the date of delivery.

Upon a Change of Control of the Company, a Free Float Event or a Delisting of the shares of the Company (as these terms are defined in the terms and conditions of the Bonds), any bondholder will have the option to require the Company to redeem all, but not some only, of its Bonds at par plus accrued but unpaid interests. In the event that the Company shares would be targeted by a public offer (in cash or in securities, in cash and securities, etc.) which may result in a Change of Control or filed following a Change of Control, and that the said offer would be declared admissible by the Autorité des marchés financiers (or its successor), upon Bondholder's conversion, the Issuer shall (i) deliver new and/or existing company shares at the prevailing Conversion/Exchange Ratio, and (ii) pay a cash amount equal to the sum of the remaining coupons scheduled until the Maturity Date, and any accrued interest.

Unless previously converted, exchanged, redeemed or purchased and cancelled, the Bonds will be redeemed at par on July 30, 2026 (the "Maturity Date").

Application will be made for the listing of the Bonds on Euronext Access™ (the open market of Euronext Paris) to occur within 30 calendar days from the Issue Date.

Settlement and delivery of the Bonds is expected to occur on or around July 30, 2021.

Bryan, Garnier & Co and J.P. Morgan AG acted as Joint Global Coordinators and Joint Bookrunners for the Bonds.

Capital Increase

The New Shares are being issued through a capital increase without shareholders' preferential subscription right reserved to a specified category of investors (investors investing the pharma sector as further described in the resolution) pursuant to the 18th resolution of the Annual General Shareholders' Meeting held on June 4, 2021.

In accordance with the Board of Directors' internal rules, the representatives of Sofinnova and of Santé Holding did not participate in the deliberations of the Board of Directors authorizing the Capital Increase.

The number of ordinary shares to be subscribed, the subscription price and the list of investors that may subscribe were decided by the Company's Chief Executive Officer (Directeur Général), in accordance with a sub- delegation granted by the Company's Board of Directors on July 22, 2021.

The subscription price of the New Shares was set at EUR 30.55, i.e. with a 3.02% discount to the last closing price (as of July 22, 2021).

Sofinnova, which held a 11.53% stake in the Company, subscribed to the Capital Increase for an amount of EUR 8M corresponding to 261,865 New Shares. After the Capital Increase, Sofinnova will hold 11.75% of the share capital of the Company. Santé Holding, which held a 3.42% stake in the Company, subscribed in the Capital Increase for an amount of EUR 3M corresponding to 98,199 New Shares. After the Capital Increase, Santé Holding will hold 3.61% of the share capital of the Company.

The Funds managed by Truffle Capital (including Holding Incubatrice), which founded Abivax, will remain the largest shareholder with 31.35%.

Settlement and delivery of the New Shares is expected to occur on or around July 27, 2021. As of their delivery, the New Shares will be fully fungible with the Company's existing shares.

The New Shares will be admitted to trading on Euronext Paris under ISIN FR0012333284 on July 27, 2021.

Bryan, Garnier & Co and J.P. Morgan AG acted as Joint Global Coordinators and Joint Bookrunners for the Capital Increase.

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Lock-up agreements

In the context of the Capital Increase, the Company has agreed to a lock-up undertaking on the issuance or sale of shares or of securities giving access to the share capital, for a period of 90 calendar days, subject to certain customary exceptions or waiver.

The Company's board members and key officers who own shares of the Company have agreed to a lock-up undertaking on the sale of shares or of securities giving access to the share capital, for a period of 90 calendar days, subject to certain customary exceptions or waiver.

Impact of the Capital Increase on the share capital

Following settlement and delivery, the New Shares will represent 11.77% of the share capital of the Company and the Company's total share capital will be EUR 166,922.68 divided into 16,692,268 shares. For illustration purposes, a shareholder holding 1% of the Company's share capital prior to the Capital Increase, will hold 0.88% of the Company's share capital upon completion of the Capital Increase (or 0.81% on a fully diluted basis).

				Ownership interest
	(%)		On a non-diluted basis		On a fully diluted basis(1)
	Before the issuance of the New Shares		1.0000%		0.9061%
	and the Bonds
	After the issuance of the New Shares only		0.8823%		0.8084%
	After issuance of the Bonds only		1.0000%		0.8710%
	After issuance of the New Shares and the		0.8823%		0.7804%
	Bonds

1. After issuance of 2,180,387 new shares resulting from the exercise of the 633,828 warrants and 578,643 founder warrants (BSPCE) and, where applicable, of the conversion of all the Bonds (based on the initial conversion/exchange ratio).

Evolution of the shareholding structure following the Transaction

The shareholding structure of the Company prior to the issuance of the New Shares and of the Bonds is set forth below:

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	Number of shares on	% of capital	% of voting rights	% of capital on a fully-	% of voting rights
Shareholders	on a non-	on a non-diluted	on a fully-diluted
a non-diluted basis	diluted basis
	diluted basis	basis	basis
Holding	210,970	1.43%	1.71%	1.30%	1.59%
Incubatrice
Truffle Capital	5,232,579	35.53%	50.21%	32.19%	46.62%
Sofinnova	1,698,723	11.53%	8.57%	10.45%	7.95%
Management	152,781	1.04%	1.49%	5.29%	4.70%
Board	778,881	5.29%	3.93%	6.01%	4.57%
Employees	8,077	0.05%	0.04%	0.50%	0.38%
Consultants	400	0.00%	0.00%	0.28%	0.22%
Other*	595,610	4.04%	3.58%	6.75%	5.68%
Treasury shares	9,200	0.06%	0.00%	0.06%	0.00%
Float	6,041,016	41.02%	30.46%	37.17%	28.29%
Total	14,728,237	100.00%	100.00%	100.00%	100.00%

• Other: long-standing minority shareholders or stock subscription warrant (BSA)/founder warrant (BCE) holders, Kepler Cheuvreux (based on the ownership disclosure thresholds declared on 03 July 2019) and former employees of the Company, former Board members and certain committee members.

The issuance of the New Shares and of the Bonds will have the following impact on the allocation of the share capital and the voting rights of the Company:

	Number of shares on	% of capital	% of voting rights	% of capital on a fully-	% of voting rights
Shareholders	on a non-	on a non-diluted	on a fully-diluted
a non-diluted basis	diluted basis
	diluted basis	basis	basis
Holding	210,970	1.26%	1.56%	1.12%	1.42%
Incubatrice
Truffle Capital	5,232,579	31.35%	45.68%	27.73%	41.53%
Sofinnova	1,960,588	11.75%	9.00%	10.39%	8.18%
Santé Holding	602,080	3.61%	2.76%	3.70%	2.92%
Management	152,781	0.92%	1.36%	4.56%	4,18%
Board (other than
Truffle Capital,	275,000	1.65%	1.26%	1.99%	1.57%
Sofinnova and
Santé Holding)
Employees	8,077	0.05%	0.04%	0.43%	0.34%
Consultants	400	0.002%	0.002%	0.25%	0.19%
Other*	595,610	3.57%	3.26%	5.82%	5.06%
Treasury shares	9,200	0.06%	0.00%	0.05%	0.00%
Investors in the
Transaction (other
than Sofinnova	1,603,967	9.61%	7.36%	11.97%	9.42%
and Santé
Holding)
Float	6,041,016	36.19%	27.72%	32.01%	25.20%
Total	16,692,268	100.00%	100.00%	100,00%	100,00%

• Other: long-standing minority shareholders or stock subscription warrant (BSA)/founder warrant (BCE) holders, Kepler Cheuvreux (based on the ownership disclosure thresholds declared on 03 July 2019) and former employees of the Company, former Board members and certain committee members.

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