title: Immunotherapy of metastatic melanoma by intratumoral injections of Vero cells producing human IL-2: phase II randomized study comparing two dose levels.
abstract: BACKGROUND
  Systemic IL-2 has shown some activity in metastatic melanoma, but its use is severely limited by toxicity. TG2001 is a product in which the human IL-2 cDNA was incorporated into the genome of Vero cells, a monkey fibroblast cell line. The goal of this intratumorally applied therapy was to create an antitumor immune response stimulated by xeno-antigens and local production of IL-2 in the close vicinity of tumor-specific antigens. TG2001 was reported to have a good safety profile in two previous dose-escalating phase I studies performed in 18 patients with various solid tumors, with encouraging clinical responses in three patients. The objectives of this study were to evaluate the tolerance and incidence of tumor regression in patients with metastatic melanoma, following repeated administration of Vero-IL-2 cells.
  
  
  METHODS
  This was on open-label, randomized phase II study comparing two doses of Vero-IL-2, 5x10(5) and 5x10(6) cells. Twenty-eight patients with metastatic melanoma were enrolled in the study, 14 in each treatment group. Patients received TG2001 by intratumoral injection on days 1, 3, and 5 every 4 weeks for four cycles, and every 8 weeks thereafter, until evidence of progressive disease (PD). Criteria for patient selection included histologically proven metastatic melanoma, with one tumor accessible for product administration, and at least another tumor site for response assessment. Evaluation included tumor measurements, humoral and T cell-mediated local and systemic immune response, humoral response to Vero cells, adverse events and standard laboratory parameters.
  
  
  RESULTS
  None of the patients achieved a confirmed objective response. Stable disease (SD) was seen in six (43%) and eight patients (57%) at the 5x10(5) and the 5x10(6) dose level, respectively. Two patients, one in each group, died during the study (i.e., within 1 month after the last injection) due to PD. Three patients exhibited antibody responses to Vero cells. T-cell immunity, serum cytokine levels and cytokine mRNA expression in tumor biopsies did not show meaningful alterations after therapy, except for a trend toward an increase in intratumoral TH2 cytokine (IL-4 and/or IL-10) levels. The study drug was well tolerated at both dose levels and side effects mainly consisted of injection site pain and erythema, and pyrexia.
  
  
  CONCLUSIONS
  The intratumoral administration of TG2001 was generally well tolerated in patients with metastatic melanoma, and transient disease stabilization was observed in 50% of patients.
authors.affiliation: Departement Innere Medizin, Abteilung für Onkologie, Kantonsspital, Petersgraben 4, CH-4031 Basel, Switzerland. crochlitz@uhbs.ch
authors.forename: Christoph
authors.initials: C
authors.lastname: Rochlitz
authors.forename: Brigitte
authors.initials: B
authors.lastname: Dreno
authors.forename: Peter
authors.initials: P
authors.lastname: Jantscheff
authors.forename: Franco
authors.initials: F
authors.lastname: Cavalli
authors.forename: Patrick
authors.initials: P
authors.lastname: Squiban
authors.forename: Bruce
authors.initials: B
authors.lastname: Acres
authors.forename: Martine
authors.initials: M
authors.lastname: Baudin
authors.forename: Bernard
authors.initials: B
authors.lastname: Escudier
authors.forename: Lucie
authors.initials: L
authors.lastname: Heinzerling
authors.forename: Rudolf
authors.initials: R
authors.lastname: Morant
authors.forename: Richard
authors.initials: R
authors.lastname: Herrmann
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Dietrich
authors.forename: Reinhard
authors.initials: R
authors.lastname: Dummer
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D002522:Chlorocebus aethiops; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007109:Immunity; D007167:Immunotherapy / Q000379:methods*; D015552:Injections, Intralesional; D007376:Interleukin-2 / Q000096:biosynthesis* / Q000235:genetics; D008297:Male; D008545:Melanoma / Q000000981:diagnostic imaging / Q000556:secondary / Q000628:therapy*; D008875:Middle Aged; D009369:Neoplasms / Q000628:therapy*; D012333:RNA, Messenger / Q000378:metabolism; D011877:Radionuclide Imaging; D013601:T-Lymphocytes / Q000276:immunology; D014183:Transplantation, Heterologous; D016896:Treatment Outcome; D014709:Vero Cells / Q000276:immunology / Q000378:metabolism*
chemical_list: D007376:Interleukin-2; D012333:RNA, Messenger