Immunotherapy is a promising emerging cancer treatment, with important products already on the market and an extensive development pipeline, especially in the fields of checkpoint inhibitors and therapeutic vaccines.
Therapeutic vaccination and CTL induction
There are currently more than 250 therapeutic vaccines in development against various types of cancers. Therapeutic vaccination is a potentially effective and powerful immunotherapeutic approach with many advantages:
Powerful: attacks cancer systemically
Specific: attacks only cancer cells expressing the tumour antigen – hence fewer side effects
Durability of action: chemotherapy has a limited action in time but vaccines continue to protect by teaching the immune system
Indications: potentially all cancers
Safety: contrary to traditional cancer treatments – immunotherapy has the potential to be extremely safe
PCI – An innovative CTL induction technology based on the use of a proprietary photosensitizer
Effective induction of CTLs (Cytotoxic T Lymphocytes) is key to realize the huge potential of therapeutic cancer vaccination, but this has been difficult to achieve with today’s vaccination technologies. PCI Biotech’s CTL induction technology may provide a solution to this problem, thereby substantially improving the potential to trigger the immune system to fight both cancers and infectious diseases.
Mechanism of action:
- Induction of CTLs is essential for the generation of an immunological response that can attack the tumour cells. Induction of CTLs is typically mediated through MHC Class I antigen presentation by antigen presenting cells (APCs).
- The PCI technology can re-localise endocytosed antigens from endosomes to the cytosol in APCs, thereby making the antigens accessible for the MHC Class I presentation machinery.
Clinical Proof of Concept for fimaVACC:
Successful clinical translation of fimaVACC and proof-of-concept by a phase I study in healthy volunteers were reported early May 2019 (link to press release)
The results show a substantial increase in number of T-cell responders to HPV E7 peptides already after two vaccinations and a clear enhancement in the T-cell responses compared to the control group. The important CD8 responses are more robust and exhibit increased functionality. The results are achieved with HPV E7 which has in numerous clinical trials shown to be notoriously difficult to induce CD8 T-cell responses for in man.
PCI Biotech’s vaccination technology platform, fimaVACC, is mainly directed at enhancing cytotoxic T-cell (CTL) responses to therapeutic and prophylactic vaccines. By releasing antigens (peptides and protein antigens) from endosomes, MHC Class I presentation is enhanced, strongly stimulating antigen specific CTL responses. In addition, fimaVACC enhances helper T-cell and antibody responses.