Isavuconazole is the latest in the long line of 'azole'-type antifungals to be developed. Of the earlier azoles some have difficulty in absorption for some people (itraconazole - Sporanox) or have quite severe side effects such as light sensitivity (voriconazole - Vfend). This latest drug has test results that indicate that it is superior in these respects to its predecessors, but this is based on laboratory and trials in quite small number of people.
This announcement does not mean that any of the prospective advantages of this drug have been proved or even whether or not it is better than the drug it is being compared with (voriconazole) - that is the end point of this trial and this is a 'mid-point' assessment which checks to overall results without knowing who is taking which drug. This is simply a statement that the drug has not had any major problems or unexpected issues during the first part of the trial and that the trial can continue. If some patients had been found who had major health problems the trial would have been stopped to prevent any further cases.
The trial will now go ahead with recruitment and treatment with the aim of completing as soon as possible in the hope of providing another useful antifungal to use in the battle against fungal infections.