The reason for the combo trial is that the FDA was

The reason for the combo trial is that the FDA was not comfortable with a mono trial. There is no mono treatment for HIV so they felt a trial to see how leronlimab fit into other combo treatments was better. I think they also would have required a huge trial size to do a mono trial. The mono trial we did do was investigational and there was a strong assumption by Nader that once the FDA saw how great leronlimab was as a mono treatment that they would convert the investigational trial into a pivotal trial. This could then lead to an approval as a mono. However this was not really going to happen and that was likely the first sighting of the Nader over- optimism.

Originally, the drug cytolin (pre leronlimab) was to be only a holiday drug to be used between other combo drug cocktails to give the patient a rest from the toxic side effects of the existing drugs. This was to be an easy approval path that would lead to mono usage of cytolin.