The drug under trial is compared to a "positive control" (i.e., a control that has a similar drug effect. So when Cayston (Gilead) was compared to TOBI several years ago, several things were different. Cayston was a TID drug, which means the antibiotic effect could have been more penetrating and/or efficacious in terms of log kill. Most certainly Cayston did not have the lipid penetration and accumulation capability. So my first impression that Arikace should be compared with a negative control (liposome alone) was correct. Now there is more work ahead for INSM and the clinical trial team. Looks like NTM is going to be the "front burner" program. Sure hope that one gets two logs of kill of various NTM bacteria.
I think one issue is the non-inferiority design. For better pricing and uptake one would want to at least see consistent numerical superiority across endpoints, and the difference between once and twice a day is not as great as three times a day. Unless some advantage is shown why would someone pay a premium price? If the stock stays down that could be a reason.
One thing they have to consider is going to a BID regimen and spreading out the amikacin effect. Looked at the charts and what was a total blind-side was the FEV1 values were comparable. They have to regain that lead effect if they are ever going to get "superiority" over TOBI. But now they have to pin their hopes on NTM.