title: Macroflux microprojection array patch technology: a new and efficient approach for intracutaneous immunization.
abstract: OBJECTIVE
  We evaluated the Macroflux microprojection array patch technology as a novel system for intracutaneous delivery of protein antigens.
  
  
  METHODS
  Macroflux microprojection array systems (330-microm micro-projection length, 190 microprojections/cm2, 1- and 2-cm2 area) were coated with a model protein antigen, ovalbumin (OVA), to produce a dry-film coating. After system application, microprojection penetration depth, OVA delivery, and comparative immune responses were evaluated in a hairless guinea pig model.
  
  
  RESULTS
  Macroflux microprojections penetrated into hairless guinea pig skin at an average depth of 100 microm with no projections deeper than 300 microm. Doses of I to 80 microg of OVA were delivered via 1- or 2-cm2 systems by varying the coating solution concentration and wearing time. Delivery rates were as high as 20 microg in 5 s. In a prime and boost dose immune response study, OVA-coated Macroflux was most comparable to equivalent doses injected intradermally. Higher antibody titers were observed when OVA was administered with the microprojection array or intradermally at low doses (1 and 5 microg). Macroflux administration at 1- and 5-microg doses gave immune responses up to 50-fold greater than that observed after the same subcutaneous or intramuscular dose. Dry coating an adjuvant, glucosaminyl muramyl dipeptide, with OVA on the Macroflux resulted in augmented antibody responses.
  
  
  CONCLUSIONS
  Macroflux skin patch technology provides rapid and reproducible intracutaneous administration of dry-coated antigen. The depth of skin penetration targets skin immune cells; the quantity of antigen delivered can be controlled by formulation, patch wearing time, and system size. This novel needle-free patch technology may ultimately have broad applications for a wide variety of therapeutic vaccines to improve efficacy and convenience of use.
authors.affiliation: Biological Sciences, ALZA Corporation, Mountain View, California 94043, USA. james.matriano@alza.com
authors.forename: James A
authors.initials: JA
authors.lastname: Matriano
authors.forename: Michel
authors.initials: M
authors.lastname: Cormier
authors.forename: Juanita
authors.initials: J
authors.lastname: Johnson
authors.forename: Wendy A
authors.initials: WA
authors.lastname: Young
authors.forename: Margaret
authors.initials: M
authors.lastname: Buttery
authors.forename: Kofi
authors.initials: K
authors.lastname: Nyam
authors.forename: Peter E
authors.initials: PE
authors.lastname: Daddona
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D000917:Antibody Formation; D000941:Antigens / Q000008:administration & dosage*; D004306:Dose-Response Relationship, Immunologic; D016503:Drug Delivery Systems / Q000379:methods*; D005260:Female; D006168:Guinea Pigs; D007114:Immunization / Q000379:methods*; D008297:Male; D008845:Microinjections / Q000379:methods*; D010047:Ovalbumin / Q000008:administration & dosage* / Q000276:immunology; D012867:Skin / Q000737:chemistry / Q000276:immunology
chemical_list: D000941:Antigens; D010047:Ovalbumin