With an Emergency IND (see link below), it looks like you inject first, ask questions later. I can understand of the first line treatment going safer as there are still options if the treatment fails, but with later lines, you would think the safety, especially with a drug with a stellar safety profile, would not be the primary concern. I will be surprised if they start with 350mg.

https://www.fda.gov/drugs/investigational-new...d-timeline