It can't be used open label with only an EUA and we don't know whether the FDA will consider an approval or not even with a successful Brazil trial. The definitely wouldn't consider it just on interim results.

The biggest reason the BLA needs to be filed is so the clock starts on getting an HIV approval because there are HIV patients with multi-drug resistance who could really use a therapeutic that is very effective, won't engender more resistance and that has no side effects, and who need the guaranteed insurance coverage an approval for that specific indication would provide.