Phase I Clinical data
In 2015 a phase I clinical trial using 124I-PEG-AVP04 as an imaging agent was completed having met its safety endpoint with no adverse events or immunogenicity. The PK and PET imaging data showed that AVP04 is stable in-vivo in man for over a week. Biodistribution showed no specific uptake in normal tissues, whilst tumour uptake was excellent, with rapid targeting of tumour (within 24 hrs) and high uptake retained for one week. Metastatic lesions in lymph nodes and liver were clearly identified and Pharmacokinetics (T½ ~ 44hrs) show improved characteristics compared to intact IgG and naked scFv/diabody.
The most notable results from the study include:
- High stability of Avibodies in vivo for over one week
- Higher tumour uptake (AUC), estimated to be at least 4 fold higher than intact antibodies
- Faster whole body clearance than intact antibodies
Taken together, these data demonstrate that Avibodies achieve a superior level of payload delivery to tumours which should translate into higher therapeutic efficacy, lower systemic toxicity and a greater therapeutic window when employed as ADCs or in RIT.