Humanigen Inc (HGENQ)

[bobshmob]

Thanks, agmcsf. Very interesting. The apparent effect of lenzilumab on downstream pro-inflammatory cytokines seems impressive in the EIND patients, and the patient recoveries seem almost miraculous. It looks like lenzilumab works great, at least in some patients. But 12 very not randomly selected patients and no controls leaves a lot of questions. That's what the P3 is all about, I suppose. But I want to learn more about how the thing works too.

Lenzilumab targets GM-CSF directly and not GM-CSF receptors, so if GM-CSF is rapidly "consumed" by cells, some (potentially large) proportion of GM-CSF would be able to bind to the cell and do its job before being disabled by lenzilumab. [Or can lenzilumab still bind to GM-CSF after the GM-CSF has been captured by the cell?] I would guess that fine-tuning the dosing and drug delivery are critical, which might help explain why it is delivered IV 3x/day.


A lot of different kinds of cells produce GM-CSF, but maybe Th17 (or Th1) are particularly important in severe covid-19. Temesgen's paper notes elevated levels of CM-CSF-secreting Th17 cells in severe cases (although the paper they cite to support that doesn't mention Th17 but discusses Th1 instead...no idea what the difference is, if any), but it does not report Th17 or Th1, so it's tough to tell.