A prospective, open-label, single-arm, multicenter trial assessed the efficacy, safety, and pharmacokinetics of ASCENIV in adult and pediatric subjects with PI. Study subjects were receiving regular IGIV replacement therapy, with a stable dose between 300 and 800 mg/kg for at least 3 months prior to participation in this trial. Subjects received an ASCENIV infusion administered every 3 or 4 weeks (both the dose and schedule depending on their prior therapy) for 12 months.
A total of 59 subjects were enrolled into the trial, 28 men and 31 women with a mean age of 42 years; 93% were Caucasian, 5% were Hispanic and 2% African American. Forty-eight subjects were adults (81%) between 17 and 74 years of age. There were 11 pediatric subjects (see Pediatric Use [8.4]), and 11 subjects (18.6%) ≥65 years of age. The oldest subject was 74 years of age. The youngest subject was 3 years of age.
There were 19 subjects with a 3-week cycle and 40 subjects with a 4-week cycle. There were 45 subjects (76%) with common variable immunodeficiency (CVID) as their primary diagnosis, followed by X-linked Agammaglobulinemia (10%), Antibody Deficiencies and ‘Other’ (7% each). The modified intent-to-treat (mITT) population included 59 subjects and was used for efficacy analysis.
The study assessed the efficacy of ASCENIV in preventing serious bacterial infections (SBIs), defined as a rate of <1.0 cases of bacterial pneumonia, bacteremia/septicemia, osteomyelitis/septic arthritis, visceral abscess, and bacterial meningitis per person-year. Secondary efficacy parameters included time to first SBI and time to first infection of any kind/seriousness, days on antibiotics (excluding prophylaxis), days off school/work due to infections, all confirmed infections of any kind or seriousness, and hospitalizations due to infection.
During the 12-month study period, zero (0) serious acute bacterial infections occurred. Thus, the mean event rate of serious, acute, bacterial infections per year was 0.0 (with an upper 1-sided 99% confidence interval of <1.0 per subject year, which met the study’s primary efficacy endpoint).
Thirty-nine percent (39%) of subjects had days off work, school or daycare due to an infection. Of the infections reported, 1 resulted in hospitalization as a post-op local wound infection from elective surgery (see Table 6). The incidence and severity of infections in adolescents were similar to those in adult subjects.
Table 6: Summary of Efficacy Results in Subjects with PISBI = serious bacterial infections.
aPerson-years: Person-time in years with 2 decimals = (the Final Clinical Visit Date - the Day 0 date+1) / 365.25,
where the final clinical visit date is defined as the specimen collection date of the final clinical visit for urinalysis,
or the specimen collection date for the clinical laboratory tests at the final clinical visit and Day 0 date is the start
date of the first ASCENIV infusion.
b Defined as bacterial pneumonia, bacterial meningitis, bacteremia/septicemia, osteomyelitis/septic arthritis, and
visceral abscess.
c The calculation of antibiotic use includes subjects who received antibiotics for therapeutic use.
|
Number of Subjects (mITT Population) Total Number of person-yearsa | 59
55.9 |
|
Infections Number of confirmed serious acute bacterial infectionsb Rate of SBIs (SBIs/total person-years)
Rate of Infections (Infections/total person-years)a | 0
0.0
3.4
|
|
Antibiotic use due to infectionc Number of subjects (%)
Days per subject per year
| 37 (63%) 32.9 |
|
Days off school/daycare/work due to infection Number of persons with days off of school, daycare or work due to infections
Total days
Days per subject per year
| 23 (39%)
93
1.7
|
|
Unscheduled Medical Visits due to infection Number of persons with unscheduled medical visits due to infections (%)
Total visits
Visits per subject per year
| 24 (41%)
54
0.97
|
|
Hospitalization due to infection Number of subjects (%)
Number of Days
Hospitalizations per subject per year
| 1 (1.7%)
5
0.02
|