BIOS Biosenic

BioSenic S.A. : Transparency notifications received from François Rieger

  PRESS RELEASE – REGULATED INFORMATION

Article 14 of the Law of 2 May 2007 on disclosure of major holdings

Mont-Saint-Guibert, Belgium, April 18, 2024, 7am CET – BIOSENIC (Euronext Brussels and Paris: BIOS), the clinical-stage company specializing in serious autoimmune and inflammatory diseases and cell therapy, today announces that it has received transparency notifications from François Rieger. Details of the notifications can be found below and the full versions of the transparency declarations are available on BioSenic's website, under the heading “Major shareholders & transparency notices”.

The transparency notification indicates that the shareholdings held by François Rieger have crossed below the threshold of 10% as a result of the issuance of new shares of BioSenic on 29 March 2024.

The notification received from François Rieger dated 5 April 2024 contains the following information:

• Reason for the notification:
• Passive crossing of a threshold
• Notification by: A person that notifies alone
• Person subject to the notification requirement: François Rieger
• Transferor of voting rights: François Rieger
• Transaction date: 29 March 2024
• Threshold that is crossed: 10%
• Denominator: 192 873 548
• Notified details:

Voting rights	Previous notification	After the transaction
Holders of voting rights	# of voting rights	# of voting rights	% of voting rights
François Rieger	18 589 361	18 589 361	9.64%
Total voting rights		18 589 361	9.64%

About BioSenic

BioSenic is a leading biotech company specializing in the development of clinical assets issued from its Medsenic’s arsenic trioxide (ATO) platform. Key target indications for the autoimmune platform include graft-versus-host-disease (GvHD), systemic lupus erythematosus (SLE), and now systemic sclerosis (SSc).Following the merger in October 2022, BioSenic combined the strategic positionings and strengths of Medsenic and Bone Therapeutics. The merger specifically enables Medsenic/Biosenic to develop an entirely new arsenal of various anti-inflammatory and anti-autoimmune formulations using the immunomodulatory properties of ATO/oral ATO (OATO).

BioSenic is based in the Louvain-la-Neuve Science Park in Mont-Saint-Guibert, Belgium. Further information is available at http://www.biosenic.com.

About the main Medsenic/BioSenic technology platform

The ATO platform provides derived active products with immunomodulatory properties and fundamental effects on the activated cells of the immune system. One direct application is its use in onco-immunology to treat GvHD (Graft-versus-Host Disease) in its chronic, established stage. cGvHD is one of the most common and clinically significant complications affecting long-term survival of allogeneic hematopoietic stem cell transplantation (allo-HSCT).

Medsenic has been successful in a phase 2 trial with its intravenous formulation, Arscimed®, which has orphan drug designation status by FDA and EMA. The company is heading towards an international phase 3 confirmatory study, with its new, IP-protected, OATO formulation. Another selected target is moderate-to-severe forms of systemic lupus erythematosus (SLE), using the same oral formulation. ATO has shown good safety and significant clinical efficacy on several affected organs (skin, mucosae, and the gastrointestinal tract). Systemic sclerosis is now full part of the clinical pipeline of Medsenic/BioSenic. This serious chronic disease badly affects skin, lungs, or vascularization, and has no current effective treatment. Preclinical studies on pertinent animal models are positive, giving good grounds to launch a phase 2 clinical protocol, using new immunomodulatory formulations of APIs recognized to be active on the immune system.

The company is currently focusing its present R&D and clinical activities on a selective, accelerated development of its autoimmune platform.

Note: The allogeneic cell therapy platform-originating from the previous listed company Bone Therapeutics company, may be of renewed interest by using isolated and purified differentiated bone marrow Mesenchymal Stromal Cells (MSCs) as a starting material for further isolation of passive or active biological subcellular elements. Indeed, these cells may provide new subcellular vesicles potentially able to deliver a unique and proprietary approach to organ repair. BioSenic is now involved in determining new patentable approaches in this complex area of cell therapy.

For further information, please contact:

BioSenic SAFrançois Rieger, PhD, CEOTel: +33 (0)671 73 31 59investorrelations@biosenic.com

International Media Enquiries:IB CommunicationsMichelle BoxallTel: +44 (0)20 8943 4685michelle@ibcomms.agency

French Investor Enquiries:Seitosei ActifinGhislaine GasparettoTel: +33 (0)1 56 88 11 22ghislaine.gasparetto@seitosei-actifin.com

Michael Scholzemichael.scholze@seitosei-actifin.com

Certain statements, beliefs and opinions in this press release are forward-looking, which reflect the company or, as appropriate, the company directors’ current expectations and projections about future events. By their nature, forward-looking statements involve a number of risks, uncertainties and assumptions that could cause actual results or events to differ materially from those expressed or implied by the forward-looking statements. These risks, uncertainties and assumptions could adversely affect the outcome and financial effects of the plans and events described herein. A multitude of factors including, but not limited to, changes in demand, competition and technology, can cause actual events, performance or results to differ significantly from any anticipated development. Forward looking statements contained in this press release regarding past trends or activities should not be taken as a representation that such trends or activities will continue in the future. As a result, the company expressly disclaims any obligation or undertaking to release any update or revisions to any forward-looking statements in this press release as a result of any change in expectations or any change in events, conditions, assumptions or circumstances on which these forward-looking statements are based. Neither the company nor its advisers or representatives nor any of its subsidiary undertakings or any such person’s officers or employees guarantees that the assumptions underlying such forward-looking statements are free from errors nor does either accept any responsibility for the future accuracy of the forward-looking statements contained in this press release or the actual occurrence of the forecasted developments. You should not place undue reliance on forward-looking statements, which speak only as of the date of this press release.