Cardiac toxicity remains the leading cause of new drug safety side-effects. Current preclinical cardiac safety assays rely on in vitro cell-based ion channel assays and ex vivo and in vivo animal models. These assays provide an indication of acute risk but they do not always predict the effect of chronic compound exposure, as recently seen with oncology drugs. Therefore, new assays are required to characterise chronic structural and functional effects in human cells earlier in drug discovery. Impedance-based technology can provide more accurate chronic cardiotoxicity measurements in an efficient manner using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs).
Development of a robust hNaV1.9 high-throughput screening assay on the Sophion Qube384 platform. This is complemented by a suite of ion channel selectivity assays and sensory neuron recordings to create a versatile screening cascade to support NaV1.9 drug discovery programmes.
Optical voltage imaging of human iPSC-derived cardiomyocytes was used to assess electrophysiological effects of compounds beyond hERG inhibition. Action potential waveform analysis revealed compound-specific and concentration-dependent changes, enabling mechanistic differentiation of multichannel activity and demonstrating a human-relevant approach for translational cardiac safety assessment.