I saw the trade mentioned and assumed it must be ASPEN-1 data drop related.
Only 8 trading days left until the 500k shares expire and with a $20 strike it tells you something. It could be they are playing the resubmission acceptance from FDA, but bottom line is someone paid a million dollars in premiums TODAY and expects a 15-20% bump in the next 8 trading days. If it doesn't happen they will lose their million in premiums.