| Pharmacokinetics
A modelled pharmacokinetic study [11] of palivizumab data from 22 clinical studies reported Palivizumab clearance increased slightly from 10.2 ml/day to 11.9 ml/day as a function of postnatal age ranging from 7 to 18 months. Covariate analysis indicated 20% higher clearance in children with chronic lung disease and in children with antidrug antibody titer values >80. Body weight-based dosing of 15 mg/kg yielded similar palivizumab concentrations in children of different gestational and postnatal ages. There was little difference in palivizumab PK between healthy term and premature infants. Simulations found the 5 monthly palivizumab doses of 15 mg/kg, used in 2 RCTs, provided greater and more prolonged palivizumab exposure than did an abbreviated dosing regimen of 3 monthly doses.
Cost
Results from economic evaluations of palivizumab prophylaxis are inconsistent across studies, ranging from highly cost-effective to not cost-effective, implying that economic findings must be interpreted with caution. [2]
The average cost of 5 doses of palivizumab for a full term male infant < 1 year, based on the 50th centile for weight, is likely to be approximately $9,323 (drug cost only, excluding outpatient clinic costs), and $14,560 for a patient between 1-2 years. For a patient on the 3rd centile, the average estimated cost is $8,385 < 1 year, and $11,806 between 1-2 years. [9] Estimated bed saving for infant age <1 year age is 3.4 days and for an infant 1 to 2 years age is 2.5 days. If bed cost is assumed to be a maximum average $3500 per day, then one admission saved results in a $11900 to $8750 hospital cost saving. Estimated pharmaceutical only cost of treatment is below:
Population
|
RSV related admission rate per 100000
|
NNT to prevent one RSV related admission
|
Cost palivizumab per admission averted 50th centile <1 year $9,323; 1-2 years $14,560 [9]
|
Cost palivizumab per admission averted 3rd centile <1 year $8,385; 1-2 years$11,806 [9]
|
Infants with CLD 0 to <6 months age [9]
|
56250
|
4
|
37292
|
33540
|
Infants with CLD 6 to <12 months age [9]
|
21430
|
9
|
83907
|
75465
|
Infants with CLD 12 to <24 months age [9]
|
7340
|
27
|
393120
|
318762
|
≤26 weeks gestation [9]
|
13900
|
14
|
130522
|
117390
|
Infants with CHD 0 to <6 months [9]
|
12080
|
17
|
158491
|
142545
|
Infants with CHD 6 to <12 months [9]
|
6350
|
32
|
298336
|
268320
|
Other condition* 0 to <6 months [9]
|
2230
|
16
|
149168
|
134160
|
Colour coding: Orange <$150000 per treatment course; green <$100000 per treatment course
* Asthma, cystic fibrosis, cancer, HIV infection, immunodeficiency, steroid therapy, chronic renal disease, diabetes mellitus, congenital anomalies of the respiratory tract, or respiratory distress syndrome.
|
