SERB Pharmaceuticals to acquire European and MENA rights to Idefirix® (imlifidase) from Hansa Biopharma for €115 million

BRUSSELS, May 19, 2026 (GLOBE NEWSWIRE) -- SERB Pharmaceuticals (“SERB”) and Hansa Biopharma AB (“Hansa”) (Nasdaq Stockholm: HNSA) today announced that they have entered into an agreement under which SERB will acquire the exclusive development and commercialisation rights to Idefirix^® (imlifidase) in the European Union, United Kingdom, Switzerland, Norway, Liechtenstein, Iceland and the Middle East and North Africa (MENA) region from Hansa for €115 million.

Idefirix^® is a differentiated treatment for the desensitisation of highly sensitised adult patients prior to kidney transplant from a deceased donor. These patients have pre-formed reactive IgG antibodies that can target donor tissue, significantly increasing the risk of antibody-mediated kidney rejection. This makes kidney transplantation in these patients very difficult and may result in patients waiting for transplantation for a lengthy or indefinite period. Of the 70,000 people in Europe with end stage renal diseases awaiting a kidney transplant each year, around 10–15% of these individuals are considered highly sensitised.^i,ii

“SERB is committed to expanding access to transplantation for highly sensitised patients who currently have very limited alternatives,” said Jeremie Urbain, Chairman of SERB Pharmaceuticals. “SERB is designed to address rare and urgent conditions, and will leverage its deep expertise, proven commercial execution and established platform across Europe and MENA to expand the reach and clinical impact of Idefirix^®.”

Under the agreement, Hansa will receive an upfront payment of €110 million and a €5 million payment upon acceptance of the filing for full approval of Idefirix^® by the European Medicines Agency (EMA). Hansa will fully support SERB in the filing and EMA review process following the reporting of the Post-Authorization Efficacy Study (PAES) topline data. SERB will assume responsibility for the long-term PAES follow-up and the ongoing paediatric study upon becoming Market Authorisation Holder, a process expected to be initiated immediately following closing of the transaction.

Completion of the transaction is subject to customary conditions, including required foreign direct investment (FDI) regulatory approval, which is expected to be completed within 60 days.

Rothschild & Co. is acting as exclusive financial advisor and Freshfields is acting as legal counsel to SERB.

Centerview Partners UK LLP is acting as exclusive financial advisor and Morgan Lewis is acting as legal counsel to Hansa.

About highly sensitised patients awaiting kidney transplantation

Highly sensitised patients are a particularly underserved group in kidney transplantation, representing an estimated 10–15% of individuals on transplant waiting lists. These patients carry high levels of pre-formed donor specific antibodies (DSA) with broad reactivity against human leukocyte antigens (HLA), typically resulting from previous transplants, blood transfusions, or pregnancies. Consequently, they face a substantial immunological barrier to transplantation, as DSAs can trigger an immediate immune response against a donor organ, leading to tissue damage and likely graft rejection. These patients are said to have a ‘positive crossmatch’, meaning their immune system is predicted to react against a potential donor organ, which prevents transplantation and can lead to prolonged and in some cases indefinite waiting times, leaving them dependent on long-term dialysis while awaiting a viable matched organ.

About Idefirix^® (imlifidase)

Idefirix^® is an antibody-cleaving enzyme originating from Streptococcus pyogenes that specifically targets and cleaves immunoglobulin G (IgG) antibodies and inhibits IgG-mediated immune response.ⁱⁱⁱ It has a rapid onset of action, cleaving IgG-antibodies and inhibiting their activity within hours after administration.

Imlifidase is conditionally approved in the European Union, Norway, Liechtenstein, Iceland and the UK under the tradename Idefirix^® for the desensitization treatment of highly sensitized adult kidney transplant patients with a positive crossmatch against an available deceased donor.

The use of Idefirix^® should be reserved for patients who are unlikely to be transplanted under the available kidney allocation system, including prioritisation programs for highly sensitised patients.^iv Idefirix^® was reviewed as part of the European Medicines Agency’s (EMA) Priority Medicines (PRIME) program.

Full EU product information can be accessed via the initial Summary of Product Characteristics found here.

In the US, the Food and Drug Administration (FDA) accepted the Biologics License Application (BLA) for imlifidase in February of 2026 and assigned a Prescription Drug User Fee Act (PDUFA) action date of December 19, 2026.

The efficacy and safety of imlifidase as a pre-transplant treatment to reduce donor-specific IgG was studied in four Phase 2 open-label, single-arm, six-month clinical trials.^{v, vi, vii, viii} Hansa is collecting further clinical evidence and will submit additional efficacy and safety data based on one observational follow-up study and one post-approval efficacy study.

About SERB Pharmaceuticals

SERB is a fast-growing global specialty pharma company designed to address rare and urgent conditions by delivering life-saving medicines when time and complexity leave no room for failure. With a model that combines biotech agility and global pharma reliability, SERB operates end-to-end across 100+ countries, ensuring 70+ essential medicines for rare diseases, rare emergency medicine, and medical countermeasures reach patients and clinicians with urgency, wherever and whenever they are needed. Our growth is driven by selective acquisitions and geographic expansion, powered by teams who go the extra mile to keep critical medicines available worldwide.

Learn more at https://SERB.com.

For further information contact:

Chris Sampson, Vice President of Corporate Communications
chris.sampson@serb.com; Tel: +44 (0)7773 251 178

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ⁱ Global Observatory on Donation and Transplantation (GODT) data, produced by the WHO-ONT collaboration.

ⁱⁱ Sypek, Matthew P. MBBS1,2,3,4; Kausman, Joshua Y. PhD3,5,6; Watson, Narelle MSc7; Wyburn, Kate PhD8; Holt, Stephen G. PhD1,2; Hughes, Peter PhD1,2; Clayton, Philip A. PhD4,9,10. The Introduction of cPRA and Its Impact on Access to Deceased Donor Kidney Transplantation for Highly Sensitized Patients in Australia. Transplantation 105(6):p 1317-1325, June 2021. doi: 10.1097/TP.0000000000003410

ⁱⁱⁱ Huang, E., Maldonado, A. Q., Kjellman, C., & Jordan, S. C. (2022). Imlifidase for the treatment of anti‑HLA antibody‑mediated processes in kidney transplantation. American Journal of Transplantation, 22(3), 691–697. doi 10.1111/ajt.16828

^iv European Medicines Agency. Idefirix^® summary of product characteristics. Available at: https://www.ema.europa.eu/en/documents/product-information/idefirix-epar-product-information_en.pdf.

^v Heidt S, et al. Highly Sensitized Patients are Well Serves by Receiving a Compatible Organ Offer Based on Acceptable Mismatches. Front Immunol. 2021;12:687254. doi 10.3389/fimmu.2021.687254

^vi Jordan SC, et al. IgG Endopeptidase in Highly Sensitized Patients Undergoing Transplantation. N Engl J Med. 2017 Aug 3;377(5):442-453. doi: 10.1056/NEJMoa1612567. Erratum in: N Engl J Med. 2017 Oct 26;377(17):1700. doi: 10.1056/NEJMx170015.

^vii Winstedt L, et al. Complete Removal of Extracellular IgG Antibodies in a Randomized Dose-Escalation Phase I Study with the Bacterial Enzyme IdeS--A Novel Therapeutic Opportunity. PLoS One. 2015 Jul 15;10(7):e0132011. doi: 10.1371/journal.pone.0132011. PMID: 26177518; PMCID: PMC4503742.

^viii Lorant T, et al. Safety, immunogenicity, pharmacokinetics, and efficacy of degradation of anti-HLA antibodies by IdeS (imlifidase) in chronic kidney disease patients. Am J Transplant. 2018 Nov;18(11):2752-2762. doi: 10.1111/ajt.14733.