The trial failing would be the ultimate short-term concern - inevitable PPS haircut of at least 50% and future dilution would be needed to get through the other trials in the pipe.
That said, them acquiring debt and forgoing the remainder of the controlled offering at this stage in the game is IMO a sign of confidence from the company and Hercules. If you choose debt over an offering, you believe the shares you are no longer selling will appreciate at a greater rate than the cost of the debt.
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