Autologous Liver Cell Transplantation A new approach to liver disease therapy Presentation at ESAO Conference, September

1. Autologous Liver Cell Transplantation A new approach to liver disease therapy Presentation at ESAO Conference, September 6th 2007, Krems Prof. Toni Lindl, (I.A.Z. München as a Partner of HumanAutoCell GmbH)

2. Content • Market and Application Area • Preclinical Development • Early Clinical Results

3. Liver Disease Problem • There are currently very limited options to treat the continuous degradation of liver function in cirrhotic patients. • While liver transplantation today is widely practiced, there is a shortage of organ supply so that many patients do not survive the waiting period for an organ. • Furthermore liver transplantation is highly expensive and requires continuous follow-on treatment. There is a strong need for a complementary treatment for liver disease that can be applied widely

4. Content • Market and Application Area • Preclinical Development • Early Clinical Results

5. Development of liver assist device based upon a tissue engineering technology • Dr. Matthias Kaufmann a was member of the Harvard laboratory of Prof Vacanti focusing on scaffold-assisted tissue engineering • First trials with liver cells took take place in Harvard in the late 80ies/ early 90ies Dr. Kaufmann succeeds in achieving proliferation of normal (non-cancerous) rat hepatocytes in vivo • Discovered optimal proliferation by co-transplantation with of langerhans islets and hepatocytes

6. Preclinical Studies • Lewis and Gunn rats provide a suitable in vivo model to show rescue of liver function • Hepatocyes from Lewis rats are able to conjugate bilirubin via glycosyltransferase reactions in contrary to Gunn rats. • Hepatocytes from Lewis rats were isolated and cultured on a polymer scaffold and subsequently implanted into the mesenterial region of the Gunn rats. • The implanted Gunn rats showed restoration of bilirubin conjugation typically after three to four weeks. • It was shown that the implants were accepted and vascularized by the host. Kaufmann et al. (1994) Transplant Proc 26: 2240 Kaufmann et al. (1999) Pediatr. Surg Int 15:168

7. HAC‘s scaffold design and function • The scaffold‘s material and its form is of a specific 3-dimensional structure • Round caves • Inner structure is built up on a specific flat surface, which has optimal characteristics for cell adhesion • >95% “air content“ or porosity inside the scaffold • Scaffold currently in use has been developed and patented • Scaffold is made of a standard material which is a worldwide admitted medical product (Resomer) • Material combines the requested stability and the right surface with the ability to dissolve within a defined period of time • Form: 20 mm diameter, 4 mm thickness (chip)

8. Picture of scaffold structure

9. Picture of cells on scaffold structure

10. Content • Market and Application Area • Preclinical Development • Early Clinical Results

11. Therapeutic Concept • First Surgery • Excision of approx. 20 to 40 gr. cirrhotic liver (from the patient) • Excision of approx. 0,3 to 1,5 gr. pancreatic tissue • Transport to laboratory under hypothermic conditions in PBS or UWS • (optimal time frame up to 4 hours) • Laboratory treatment of cells • Dissolving of intercellular matrix (isolation of liver cells and pancreatic islets) • Incubation of cell mix on scaffolds for approx. 30 to 60 hours • Return transport to clinic (approx. 48 -65 hours upon first surgery) • Second Surgery • Implantation of scaffolds in the peritoneum (small intestine area) • Follow up • Liver function and overall condition are monitored at regular intervalls

12. Laboratory protocol • Autologous patient samples are transported to I.A.Z.- laboratory • Principal Steps are: • Perfusion of liver/ pancreas pieces with EDTA/PBS- and then with collagenase/ hyaluronidase solution • Cutting and sieving of dissolved tissue into single cells • Cells are suspended in culture medium with patients serum • Measurement of viability and number of cells • Incubation of cells on polymer scaffold for 24 to 48 hours • Finally seeded scaffold chips are transported back to the clinic

13. Perfusion apparatus

14. Photographs first surgery

15. Photographs first surgery

16. Photographs second surgery

17. Photographs second surgery

18. Results of Clinical Treatment • 46 Patients have received HeparAutoCell-treatment since September 2004 • Patients fall into three risk categories, assessed by MELD and/or CHILD score • Suited for patients especially in the medium risk group, which enjoy higher than predicted survival time, not suited for patients in high risk group. • Relevant liver parameters have developed favorably, e.g. liver parameters have significantly improved or even normalized • 4 Patients (out of the first 10) being unable to work before treatment have returned to employment • Patients listed on the transplantation list have been removed from the list due to their improved or normalized health/ liver parameters