Baseline characteristics of participants
| Characteristic . | Cohort 1 (2.0 × 1011 vg/kg) . | Cohort 2 (1.0 × 1012 vg/kg) . | Cohort 3 (3.0 × 1012 vg/kg) . | |||||
|---|---|---|---|---|---|---|---|---|
| Participant no. | 1 | 2 | 3 | 4 | 5 | 8 | 6 | 7 |
| Age at informed consent, y | 25 | 29 | 25 | 21 | 24 | 69 | 31 | 20 |
| F9 mutation HGVS* | p.Ser365Argfs*2 | p.Arg-4Gln; p.Arg43Gln | p.Gln121*; p.Gln167* | p.Tyr325*; p.Tyr371* | P.Arg180Trp | p.Ile214HisfsX8 | p.Lys440Glu | p.I316T |
| Baseline FIX activity at screening,† IU/mL | 0.005 | 0.008 | 0.02 | <0.005 | 0.009 | 0.011 | 0.018 | 0.021 |
| Baseline CRM status | Negative | Positive | Negative | Negative | Positive | Negative | Positive | Negative |
| Prior prophylactic FIX replacement therapy (past 12 mo) | No | Yes | Yes | No | No | Yes | Yes | Yes |
| Annualized bleeding rate | 12 | 12 | 7.2 | 12 | 24 | 0 | 3 | 0 |
| Average no. of FIX infusions per year | 24 | 60 | 48 | 12 | 36 | 72 | 48 | 96 |
| HIV status | Negative | Negative | Negative | Negative | Negative | Negative | Negative | Negative |
| HCV antibody status | Negative | Positive | Negative | Negative | Negative | Positive | Negative | Negative |
| Anti-AAV8 NAb titer | <1:5 | <1:5 | <1:5 | <1:5 | <1:5 | <1:5 | <1:5 | <1:5 |
| Anti-AAV2 NAb titer | <1:5 | <1:5 | 1:10 | 1:5 | <1:5 | <1:5 | <1:5 | <1:5 |
| Characteristic . | Cohort 1 (2.0 × 1011 vg/kg) . | Cohort 2 (1.0 × 1012 vg/kg) . | Cohort 3 (3.0 × 1012 vg/kg) . | |||||
|---|---|---|---|---|---|---|---|---|
| Participant no. | 1 | 2 | 3 | 4 | 5 | 8 | 6 | 7 |
| Age at informed consent, y | 25 | 29 | 25 | 21 | 24 | 69 | 31 | 20 |
| F9 mutation HGVS* | p.Ser365Argfs*2 | p.Arg-4Gln; p.Arg43Gln | p.Gln121*; p.Gln167* | p.Tyr325*; p.Tyr371* | P.Arg180Trp | p.Ile214HisfsX8 | p.Lys440Glu | p.I316T |
| Baseline FIX activity at screening,† IU/mL | 0.005 | 0.008 | 0.02 | <0.005 | 0.009 | 0.011 | 0.018 | 0.021 |
| Baseline CRM status | Negative | Positive | Negative | Negative | Positive | Negative | Positive | Negative |
| Prior prophylactic FIX replacement therapy (past 12 mo) | No | Yes | Yes | No | No | Yes | Yes | Yes |
| Annualized bleeding rate | 12 | 12 | 7.2 | 12 | 24 | 0 | 3 | 0 |
| Average no. of FIX infusions per year | 24 | 60 | 48 | 12 | 36 | 72 | 48 | 96 |
| HIV status | Negative | Negative | Negative | Negative | Negative | Negative | Negative | Negative |
| HCV antibody status | Negative | Positive | Negative | Negative | Negative | Positive | Negative | Negative |
| Anti-AAV8 NAb titer | <1:5 | <1:5 | <1:5 | <1:5 | <1:5 | <1:5 | <1:5 | <1:5 |
| Anti-AAV2 NAb titer | <1:5 | <1:5 | 1:10 | 1:5 | <1:5 | <1:5 | <1:5 | <1:5 |
According to Human Genome Variation Society nomenclature.
Retesting of FIX activity at screening was performed to ensure appropriate washout from exogenous FIX, specified in the study protocol as at least 5 days after a dose of exogenous short half-life recombinant FIX or 15 days if the participant was using extended half-life FIX.