Oral Presentation 2015 Annual Meeting of the Australasian Society for Dermatology Research

Evaluating a brain tumour targeting fluorescent marker for melanoma and non-melanoma skin cancer activity in volunteers using in vivo fluorescence imaging (#35)

Miko Yamada 1 , Julia Parrish-Novak 2 , H. Peter Soyer 1 , Dennis M Miller 2 , Lynda Spelman 3 , Tarl Prow 1
  1. Dermatology Research Center, School of Medicien, University of QLD, Translational Research Institute, Princess Alexandra Hospital, QLD, Australia
  2. Blaze Biosceince Inc, Seattle, USA
  3. Specialist Connect , Brisbane , QLD, Australia

Skin cancer screening, excision and follow up could be improved by identifying tumours and margins with more precision. Targeted fluorescence markers combined with in vivo fluorescence imaging have  potential to enhance the contrast between tumour and non-tumour tissue.

We evaluated BLZ-100 or Tumor Paint™, which is a well documented tumour targeting peptide conjugated to indocyanin green, a near-infrared dye,that is ideal for clinical fluorescence imaging for potential use in skin cancer applications. Our imaging goal was to evaluate clinical fluorescence imaging, multi-imaging modality lesion registration, lesion contrast improvement and histopathological correlation.

Human ethics approval was obtained to conduct a Phase-I dose escalation study of BLZ-100 with non-melanotic skin cancer patients. This was successfully completed from 3 mg to 18 mg. A melanoma expansion cohort was conducted at the 6 mg dose based on the non-melanoma skin cancer cohorts. BLZ-100 was administered as a single intravenous injection. A clinical fluorescence-imaging device (Fluobeam® 800, Fluoptics, Grenoble, France) was used for clinical fluorescence imaging to assess BLZ-100 accumulation in skin lesions prior to excision. Base-line (pre-dose) fluorescence images were taken to evaluate skin autofluorescence in lesional and peri-lesional skin. Additional images were taken at 2, 4, 24 and 48 hours after dose administration.

Non-melanoma imaging outcomes showed BLZ-100 accumulation in a sub-set of histopathologically confirmed basal cell carcinomas. Six subjects were enrolled in the expansion study with four histopathologically confirmed level 1 melanomas. Three of four melanoma cases showed obvious fluorescence accumulation that correlated with the expected tumour location, with highest occurring at 2hr post infusion. A maximum of 2-fold increase in the lesion over peri-lesional was observed. One patient with a histopathologically diagnosed actinic keratosis also showed a clear visible signal at 2hr post infusion.

In conclusion, BLZ-100 has shown potential for tumour targeting imaging including low grade melanoma.