IgG antibodies constitute an important element of the protective immune response, but can, in some situations, be pathogenic or harmful. By transplanting organs or tissue from one individual to another, the recipient’s immune system is exposed to foreign antigens. The IgG response to “non-self” donor tissues and the resulting immune system activation may prevent patients from receiving life altering therapies, such as organ transplantation.
Kidney transplantation is a lifesaving treatment for patients with kidney failure, also known as end-stage renal disease (ESRD), a serious condition affecting almost 2.5 million patients worldwide1.
People who progress to ESRD will require renal replacement therapy, which involves either dialysis or kidney transplantation. Patients dependent on dialysis may need up to six hours of treatment three to four times per week2, which for most patients results in significantly impaired quality of life. Receiving a transplant is life-changing, offering a better quality of life at lower societal cost compared to dialysis3.
Across the U.S. and Europe, approximately 170,000 patients are waiting for a kidney transplant, with over 50,000 new patients added to the kidney transplant waiting list each year (20,000 in European Union and United Kingdom, 32,000 in the U.S.)4. Of these between 10 and 15% are classified as highly sensitized, causing them to face extended time on transplant waiting lists due to a broad reactivity against human leukocyte antigens (HLA) that makes the identification of an immunologically suitable donor organ more difficult1,5.
Highly sensitized patients
Transplant patients are classified as highly sensitized when they have donor-specific antibodies (DSAs) with a broad reactivity against human leukocyte antigens (HLAs), which cause an immune response against non-self tissues such as a donor's organ6. These donor-specific antibodies (DSAs) are the result of prior immune response to human leukocyte antigens (HLA) developed through pregnancy, blood transfusions and/or previous transplants7. DSAs carry the risk of causing significant tissue damage and potential rejection if they are present at the time of transplantation6.
The presence of DSAs is either an absolute or relative contraindication, depending on the breadth and strength of the antibody response. Due to their presence, highly sensitized patients have longer waiting times without access to a potentially lifesaving kidney transplant within the national allocation system or prioritization programs8,9. Across the U.S. and Europe, highly sensitized patients comprise around 10-15% of transplant waiting lists1,5.
Our commitment to highly sensitized patients
At Hansa Biopharma, we are committed to finding and developing solutions that can help address the unmet medical needs of highly sensitized patients. Our first treatment has been granted conditional authorization by the European Commission in the European Union (EU)/EAA and the United Kingdom (UK) as the first desensitization treatment of highly sensitized adult kidney transplant patients with a positive crossmatch against an available deceased donor10.
Taking care of a transplanted kidney through physical and mental health
“And people say to me: I never would have guessed that you had a kidney transplant… when I hear those words, they keep me motivated, and keep me going.”
Life on tour with chronic kidney disease
“I had always played the guitar and wrote songs but never really did anything with it. Nothing was going to hold me back now! No more excuses… there wasn’t time!”
Antibody-mediated graft rejection
Acute antibody-mediated rejection (AMR) is one of the biggest risks for patients after a transplant. By transplanting organs or tissue from one individual to another, a process known as allogeneic transplantation, the recipient’s immune system is exposed to foreign antigens. As part of a natural immune response against the graft, the immune system can develop donor-specific antibodies, or DSAs, that are specific to the transplant. These DSAs can cause an AMR that may eventually result in an unsuccessful transplantation.
In kidney transplantation, AMR occurs in approximately 5-7%11 of patients and is the main cause for transplants failure. There are approximately 70,000 kidney patients on transplant waiting lists across the European Union (EU) and the United Kingdom (UK) and approximately 400,000 who currently live with a kidney transplant12.
We are conducting a Phase 2 study in AMR, designed to evaluate the safety and efficacy of imlifidase in eliminating the donor specific antibodies (DSAs) that cause AMR. The patients are also included in a long-term follow up trial to evaluate the long-term outcome of graft survival.
1. Jordan SC, et al. Transplantation. 2021 Aug 1;105(8):1808-1817
2. National Institute of Diabetes and Digestive and Kidney Diseases. Hemodialysis. Available at: https://www.niddk.nih.gov/health-information/kidney-disease/kidney-failure/hemodialysis. Last accessed: November 2021.
3. Axelrod DA, et al. Am J Transplant. 2018;18(5):1168-1176
4. Newsletter Transplant 2015-2021. Available at: https://freepub.edqm.eu/publications. Last accessed November 2021.
5. ESOT Transplantation Learning Journey Highlights 15-17 November 2020-pg 25. Available at https://esot.org/scientific-highlights-transplantation-learning-journey-tlj-2-0/ Last accessed: Feb 2022
6. Eurostam Report (A Europe-wide strategy to enhance transplantation of highly sensitized patients on the basis of acceptable HLA mismatches.) Available at https://cordis.europa.eu/project/id/305385/reporting. Last accessed November 2021
7. Manook M, et al. Lancet. 2017; 389(10070):727-734
8. Redfield R, et al. Nephrol Dial Transplant. 2016; 31:1746–1753
9. Lonze BE, et al. Ann Surg. 2018; 268(3):488-496
10. European Medicines Agency. Available at: https://www.ema.europa.eu/en/medicines/human/EPAR/idefirix. Last accessed: November 2021.
11. Puttarajappa C, et al. J. Transplant. 2012; 2012:193724
12. Global Observatory on donation & transplant