RE: Avacta University Affimer Project continues to deliver14 Aug 2023 16:40
The Avacta 2019 report is an interesting read. Would be good if all these share options preventing the Board buying shares were linked to delivery....
The first Affimer clinical development
candidate AVA004-251,
a PD-L1 antagonist, has been selected and initial cell line development successfully completed. GMP production of AVA004-251 is on hold whilst the Group focuses its resources on AVA6000.
Progress in the development of the AVA6000 prodoxorubicin has been outlined above. The clinical development plans (Phase 1b and 2) for this molecule include combinations with a PD-L1 antagonist in a range of solid tumours carried out with Avacta’s AVA004-251 molecule, or with a partner’s PD(L)1 inhibitor.
The first of Avacta’s TMACs combines an Affimer PD-L1 inhibitor with a powerful chemotherapy called AVA100 I-DASH (also known as Talabostat Mesylate) that kills macrophage in the tumour microenvironment leading to a significant inflammatory event that attracts the immune system to the tumour. The immune response is then supported by the presence of the Affimer PD-L1 blockade.
Initial efficacy data in mice have been generated by co-administration (two separate molecules) of the lead Affimer PD-L1 candidate AVA004-251 with AVA100 as two separate drugs as an intermediate step towards generating these data for the TMAC. These data show that AVA004-251 performs as effectively as Atezolizumab, a marketed PD-L1 antibody, and
also show a synergistic effect of the combination of AVA004-251 with AVA100 as anticipated. In fact, tumours in the animals treated with the combination of the two showed complete regression and developed an immunity to being re-challenged with the same tumour 60 days later.
In order to carry out the same evaluation with the TMAC, an appropriate mouse efficacy model that has been modified to contain the FAP enzyme required to release the chemotherapy from the TMAC has been developed. Postperiod end, the first data from this engineered mouse model were obtained and clear synergy between the released warhead and AffimerPD-L1 inhibitor was seen, causing a significant slowdown in tumour growth compared with the approved PD-L1 monoclonal antibody inhibitor Avelumab. A number of further pre-clinical animal studies are now planned for 2020 to investigate in detail the optimum TMAC structure.