title: Phase I and pharmacokinetic studies of CYT-6091, a novel PEGylated colloidal gold-rhTNF nanomedicine.
abstract: OBJECTIVE
  A novel nanomedicine, CYT-6091, constructed by simultaneously binding recombinant human tumor necrosis factor alpha (rhTNF) and thiolyated polyethylene glycol to the surface of 27-nm colloidal gold particles, was tested in a phase I dose escalation clinical trial in advanced stage cancer patients.
  
  
  METHODS
  CYT-6091, whose dosing was based on the amount of rhTNF in the nanomedicine, was injected intravenously, and 1 cycle of treatment consisted of 2 treatments administered 14 days apart.
  
  
  RESULTS
  Doses from 50 μg/m(2) to 600 μg/m(2) were well tolerated, and no maximum tolerated dose (MTD) was reached, as the highest dose exceeded the target dosage of 1-mg rhTNF per treatment, exceeding the previous MTD for native rhTNF by 3-fold. The first 2 patients on the study, each receiving 50 μg/m(2), did not receive any prophylactic antipyretics or H2 blockade. A predicted, yet controllable fever occurred in these patients, so all subsequently treated patients received prophylactic antipyretics and H2 blockers. However, even at the highest dose rhTNF's dose-limiting toxic effect of hypotension was not seen. Using electron microscopy to visualize nanoparticles of gold in patient biopsies of tumor and healthy tissue showed that patient biopsies taken 24 hours after treatment had nanoparticles of gold in tumor tissue.
  
  
  CONCLUSIONS
  These data indicate that rhTNF formulated as CYT-6091 may be administered systemically at doses of rhTNF that were previously shown to be toxic and that CYT-6091 may target to tumors. Future clinical studies will focus on combining CYT-6091 with approved chemotherapies for the systemic treatment of nonresectable cancers.
authors.affiliation: Surgery Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA.
authors.forename: Steven K
authors.initials: SK
authors.lastname: Libutti
authors.forename: Giulio F
authors.initials: GF
authors.lastname: Paciotti
authors.forename: Adriana A
authors.initials: AA
authors.lastname: Byrnes
authors.forename: H Richard
authors.initials: HR
authors.lastname: Alexander
authors.forename: William E
authors.initials: WE
authors.lastname: Gannon
authors.forename: Melissa
authors.initials: M
authors.lastname: Walker
authors.forename: Geoffrey D
authors.initials: GD
authors.lastname: Seidel
authors.forename: Nargiza
authors.initials: N
authors.lastname: Yuldasheva
authors.forename: Lawrence
authors.initials: L
authors.lastname: Tamarkin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry / Q000493:pharmacokinetics; D004305:Dose-Response Relationship, Drug; D005260:Female; D017979:Gold Colloid / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry / Q000493:pharmacokinetics; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D020714:Maximum Tolerated Dose; D008875:Middle Aged; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry; D009369:Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D011092:Polyethylene Glycols / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry / Q000493:pharmacokinetics; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry / Q000493:pharmacokinetics; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry / Q000493:pharmacokinetics*; D055815:Young Adult
chemical_list: D000970:Antineoplastic Agents; D017979:Gold Colloid; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D011092:Polyethylene Glycols