My understanding is that the 3-fold was the original pre-print and the 9-fold was the most recent preprint. The difference is in the number of days monitored...
The original preprint (from 8/23) doesn't state the observation timeline, so my guess is it was in the twenty-something-days range.
The new preprint (from 9/5) says the observation occurred at 60 days.
8/23 Results: So far, 19 of 21 patients have survived. Improved radiographic appearance was seen in both lungs of 17 patients and in one lung of 2 patients. A mean 3-fold increase in PaO2:FiO2 ratio was seen with complete remission from respiratory failure in 9 patients and ongoing improvement in 10. Seven patients were discharged from the hospital, 7 sent to intermediate care, and 5 remain in the ICU. Three of 5 patients on ECMO have been decannulated and two have been discharged. A 75% (95% CI±3%: P<.001) reduction in IL-6 was seen with corresponding decrease in C-reactive protein. A median 4 point reduction in the NIAID Ordinal Scale was observed (P<.01).
10/5 Findings: In this administratively-controlled clinical trial, intravenous aviptadil, administered as 3 successive 12 hour infusions of 50/100/150 pmol/kg/hr resulted in a 9-fold advantage in both survival and recovery from respiratory failure compared to standard of care with all approved therapy for COVID-19 among patients treated in the same ICU by the same clinical care team. Notably, 4 of 5 aviptadil-treated patients on Extracorporeal Membrane Oxygenation were successfully decannulated and survived, compared to 3 of 13 control patients. Although 20% of patients exhibited hypotension and/or diarrhea, no drug-related serious adverse events were seen.