CLSN ended the day down 2.82 percent at $7.58 after reaching a high of $8.35 earlier in the session. The cancer-drug developer was down at $2 in mid-June but bounced off support at $4.30 early this month.
A February put spread topped the action. A trader sold 5,000 February 2 puts for the bid price of $0.70 against open interest of 6,260 contracts, according to optionMONSTER's tracking systems. At the same time, he or she bought 5,000 February 4.50 puts for the ask price of $2.25 in volume that was more than the previous open interest at that strike, so it was a new position.
This could be a roll, with the trader selling the lower-strike puts and buying the higher contracts to get more bang for their buck, or delta, on a pullback. Alternatively, it could be a new vertical spread that would take a maximum gain if shares are back down around $2 by that expiration.
In either case, this doesn't appear to be hedging on a long position because of how far out of the money the puts are. Celsion saw bullish option trading twice in the last week.
