Cost-Utility Analysis of Mycophenolate Mofetil versus Azathioprine Based Regimens for Maintenance Therapy of Proliferative Lupus Nephritis

Table 4

(a) Costs, effectiveness, and incremental cost effectiveness ratios (ICER) of the base-case and individual clinical trials in lifetime model (40 years). (b) Sensitivity analysis of lifetime model using Cochrane data.

(a)

Scenarios	Total cost ($)	Total effectiveness (QALY)	Incremental costs ($)	Incremental effectiveness (QALY)	ICER ($/QALY)
Cochrane (base-case)
AZA	478,333.42	14.1623
MMF	484,309.78	15.0882	5976.36	0.9260	6454.24
Subgroups
ALMS
AZA	485,791.18	13.5979
MMF	493,953.07	15.4554	8161.89	1.8575	4393.90
MAINTAIN
AZA	469,825.11	14.0140
MMF	486,758.11	14.3225	16,933.00	0.3085	54,891.42

QALY: quality-adjusted life-years; AZA: azathioprine; MMF: mycophenolate mofetil.

(b)

Scenarios	ICER MMF versus AZA (US$)
Base-case (40-year time horizon)	$6,454.24
Excluding indirect costs	Dominant
Utility
Remission 0.8 (versus base-case 0.7)	$4067.55
Relapse 0.5 (versus base-case 0.6)	$5,808.27
Relapse 0.7 (versus base-case 0.6)	$7,695.58
Increase in probability of ESRD with relapse
0.5% per year	$4590.37
1.0% per year	$3112.96
2.0% per year	$2717.08
Extrapolated treatment effect after 3-year maintenance therapy
Same as during treatment phase (base-case)	$6,454.24
No treatment effect from both MMF and AZA during extrapolated phase	$428,894.16
Treatment effect from both MMF and AZA decreases 1% per year	$15,096.38
Treatment effect from both MMF and AZA decreases 2% per year	$25,713.36
Time horizon (number of years after maintenance therapy)
5 years	$513,712.88
10 years	$67,203.94
20 years	Dominant
30 years	$5,232.11
Discount rate (base-case 3% for costs and utility)
0%	$5,830.11
5%	$10,230.91
7%	$14,374.62

ICER: incremental cost effectiveness ratio; AZA: azathioprine; MMF: mycophenolate mofetil; ESRD: end stage renal disease.
MMF is less costly and more effective than AZA-based regimen.
Assuming 100% probability of relapse during remission on either MMF or AZA after completing 3-year maintenance therapy.
Assuming 1% or 2% per year increase in relapse during remission on either MMF or AZA after completing 3-year maintenance therapy.