title: Preclinical good laboratory practice-compliant safety study to evaluate biodistribution and tumorigenicity of a cartilage advanced therapy medicinal product (ATMP).
abstract: BACKGROUND
  The clinical development of advanced therapy medicinal products (ATMPs), a new class of drugs, requires initial safety studies that deviate from standard non-clinical safety protocols. The study provides a strategy to address the safety aspects of biodistribution and tumorigenicity of ATMPs under good laboratory practice (GLP) conditions avoiding cell product manipulation. Moreover, the strategy was applied on a human ATMP for cartilage repair.
  
  
  METHODS
  The testing strategy addresses biodistribution and tumorigenicity using a multi-step analysis without any cell manipulation to exclude changes of test item characteristics. As a safeguard measurement for meeting regulatory expectations, the project design and goals were discussed continuously with the regulatory authority using a staggered scientific advice concept. Subsequently, the strategy was applied to co.don chondrosphere® (huChon spheroid), a tissue-engineered matrix-free ATMP of human normal chondrocytes. In both the biodistribution and tumorigenicity studies, huChon spheroids were implanted subcutaneously into 40 immunodeficient mice. Biodistribution was studied 1 month after implantation. A skin disc containing the huChon spheroid, two surrounding skin rings and selected organs were analyzed by validated, gender-specific, highly-sensitive triplex qPCR and by immunohistochemistry (IHC).
  
  
  RESULTS
  No human DNA was detected in distant skin rings and analyzed organs. IHC revealed no direct or indirect indications of cell migration. Tumorigenicity was assessed 6 months after huChon spheroid implantation by palpation, macroscopic inspection, histology and IHC. No mice from the huChon spheroid group developed a tumor at the implantation site. In two mice, benign tumors were detected that were negative for HLA-ABC, suggesting that they were of spontaneous murine origin.
  
  
  CONCLUSIONS
  In summary, the presented strategy using a multi-step analysis was confirmed to be suitable for safety studies of ATMPs.
authors.affiliation: Translational Centre for Regenerative Medicine (TRM), University of Leipzig, Leipzig, Germany. mzscharnack@gmail.com.|Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany. mzscharnack@gmail.com.|Centre for Biotechnology and Biomedicine (BBZ), University of Leipzig, Leipzig, Germany. mzscharnack@gmail.com.
authors.forename: Matthias
authors.initials: M
authors.lastname: Zscharnack
authors.affiliation: Translational Centre for Regenerative Medicine (TRM), University of Leipzig, Leipzig, Germany. Christoph.Krause@medizin.uni-leipzig.de.|Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany. Christoph.Krause@medizin.uni-leipzig.de.
authors.forename: Christoph
authors.initials: C
authors.lastname: Krause
authors.affiliation: Research Laboratories, Department of Surgery, University of Leipzig, Leipzig, Germany. Gabriela.Aust@medizin.uni-leipzig.de.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Aust
authors.affiliation: Translational Centre for Regenerative Medicine (TRM), University of Leipzig, Leipzig, Germany. Christian.Thuemmler@bbz.uni-leipzig.de.
authors.forename: Christian
authors.initials: C
authors.lastname: Thümmler
authors.affiliation: Translational Centre for Regenerative Medicine (TRM), University of Leipzig, Leipzig, Germany. Frank.Peinemann@bbz.uni-leipzig.de.
authors.forename: Frank
authors.initials: F
authors.lastname: Peinemann
authors.affiliation: ACOMED Statistik, Leipzig, Germany. tk@acomed-statistik.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Keller
authors.affiliation: co.don AG, Teltow, Germany. j.smink@codon.de.
authors.forename: Jeske J
authors.initials: JJ
authors.lastname: Smink
authors.affiliation: Translational Centre for Regenerative Medicine (TRM), University of Leipzig, Leipzig, Germany. Heidrun.Holland@medizin.uni-leipzig.de.
authors.forename: Heidrun
authors.initials: H
authors.lastname: Holland
authors.affiliation: Department of Orthopaedics, University of Texas HSC San Antonio, San Antonio, USA. jeremysomerson@gmail.com.
authors.forename: Jeremy S
authors.initials: JS
authors.lastname: Somerson
authors.affiliation: Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany. jens.knauer@izi.fraunhofer.de.
authors.forename: Jens
authors.initials: J
authors.lastname: Knauer
authors.affiliation: Translational Centre for Regenerative Medicine (TRM), University of Leipzig, Leipzig, Germany. Ronny.Schulz@bbz.uni-leipzig.de.|Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany. Ronny.Schulz@bbz.uni-leipzig.de.|Centre for Biotechnology and Biomedicine (BBZ), University of Leipzig, Leipzig, Germany. Ronny.Schulz@bbz.uni-leipzig.de.
authors.forename: Ronny M
authors.initials: RM
authors.lastname: Schulz
authors.affiliation: Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany. joerg.lehmann@izi.fraunhofer.de.
authors.forename: Jörg
authors.initials: J
authors.lastname: Lehmann
mesh_terms: D000818:Animals; D018938:Caco-2 Cells; D002356:Cartilage / Q000473:pathology*; D019902:Chondrocytes / Q000166:cytology; D005260:Female; D015316:Genetic Therapy / Q000592:standards; D006801:Humans; D007621:Karyotyping; D007753:Laboratories; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D041681:NIH 3T3 Cells; D009368:Neoplasm Transplantation; D061214:Patient Safety; D011446:Prospective Studies; D011786:Quality Control; D023822:Tissue Engineering / Q000592:standards*