[ma2t]

Yes, Sanofi licensed from Kymab. There are a few groups targeting ICOS/ICOSL to modulate immune response to tumor (either alone or in combo with PD-1, CTLA-4, etc approaches previously mentioned on HN). Here's one reasonably recent backgrounder on rationale: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7003380/

Still not clear that KY1044 really is the "experimental drug" mentioned in the linked BBC article, since as others have noted the article is pretty thin on detail.