title: A First-Time-In-Human Phase I Clinical Trial of Bispecific Antibody-Targeted, Paclitaxel-Packaged Bacterial Minicells.
abstract: BACKGROUND
  We have harnessed a novel biological system, the bacterial minicell, to deliver cancer therapeutics to cancer cells. Preclinical studies showed that epidermal growth factor receptor (EGFR)-targeted, paclitaxel-loaded minicells (EGFRminicellsPac) have antitumor effects in xenograft models. To examine the safety of the minicell delivery system, we initiated a first-time-in-human, open-label, phase I clinical study of EGFRminicellsPac in patients with advanced solid tumors.
  
  
  METHODS
  Patients received 5 weekly infusions followed by a treatment free week. Seven dose levels (1x108, 1x109, 3x109, 1x1010, 1.5x1010, 2x1010, 5x1010) were evaluated using a 3+3 dose-escalation design. Primary objectives were safety, tolerability and determination of the maximum tolerated dose. Secondary objectives were assessment of immune/inflammatory responses and antitumor activity.
  
  
  RESULTS
  Twenty eight patients were enrolled, 22 patients completed at least one cycle of EGFRminicellsPac; 6 patients did not complete a cycle due to rapidly progressive disease. A total of 236 doses was delivered over 42 cycles, with a maximum of 45 doses administered to a single patient. Most common treatment-related adverse events were rigors and pyrexia. No deaths resulted from treatment-related adverse events and the maximum tolerated dose was defined as 1x1010 EGFRminicellsPac. Surprisingly, only a mild self-limiting elevation in the inflammatory cytokines IL-6, IL-8 and TNFα and anti-inflammatory IL-10 was observed. Anti-LPS antibody titers peaked by dose 3 and were maintained at that level despite repeat dosing with the bacterially derived minicells. Ten patients (45%; n = 22) achieved stable disease as their best response.
  
  
  CONCLUSIONS
  This is the first study in humans of a novel biological system that can provide targeted delivery of a range of chemotherapeutic drugs to solid tumor cells. Bispecific antibody-targeted minicells, packaged with the chemotherapeutic paclitaxel, were shown to be safe in patients with advanced solid tumors with modest clinical efficacy observed. Further study in Phase II trials is planned.
  
  
  BACKGROUND
  Australian New Zealand Clinical Trials Registry ACTRN12609000672257.
authors.affiliation: Department of Hematology and Medical Oncology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Solomon
authors.affiliation: Medical Oncology, Royal Melbourne Hospital, Melbourne, Victoria, Australia.
authors.forename: Jayesh
authors.initials: J
authors.lastname: Desai
authors.affiliation: Medical Oncology, Royal Melbourne Hospital, Melbourne, Victoria, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Rosenthal
authors.affiliation: Department of Hematology and Medical Oncology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.
authors.forename: Grant A
authors.initials: GA
authors.lastname: McArthur
authors.affiliation: Cancer Therapeutics, EnGeneIC Ltd, Sydney, New South Wales, Australia.
authors.forename: Scott T
authors.initials: ST
authors.lastname: Pattison
authors.affiliation: Cancer Therapeutics, EnGeneIC Ltd, Sydney, New South Wales, Australia.
authors.forename: Stacey L
authors.initials: SL
authors.lastname: Pattison
authors.affiliation: Cancer Therapeutics, EnGeneIC Ltd, Sydney, New South Wales, Australia.
authors.forename: Jennifer
authors.initials: J
authors.lastname: MacDiarmid
authors.affiliation: Cancer Therapeutics, EnGeneIC Ltd, Sydney, New South Wales, Australia.
authors.forename: Himanshu
authors.initials: H
authors.lastname: Brahmbhatt
authors.affiliation: Olivia Newton-John Cancer and Wellness Centre, Austin Hospital, Heidelberg, Victoria, Australia.|Ludwig Institute for Cancer Research, Austin Hospital, Heidelberg, Victoria, Australia.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Scott
mesh_terms: D000328:Adult; D018033:Antibodies, Bispecific / Q000009:adverse effects / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use; D016207:Cytokines / Q000378:metabolism; D003710:Demography; D005260:Female; D006801:Humans; D008070:Lipopolysaccharides; D008297:Male; D008875:Middle Aged; D017239:Paclitaxel / Q000627:therapeutic use*; D012486:Salmonella typhimurium / Q000166:cytology*
chemical_list: D018033:Antibodies, Bispecific; D000970:Antineoplastic Agents; D016207:Cytokines; D008070:Lipopolysaccharides; D017239:Paclitaxel