Table 2.

Inputs used in model

Variable	Source
Health state transitions: proportion of patients sitting or walking.	onasemnogene abeparvovec: AVXS-101-CL-101 [NCT02122952][8,28] nusinersen: ENDEAR [NCT02193074][17] and SHINE [NCT02594124][16] BSC: No sitting/walking patients.
Health state transitions: Probability of death or permanent ventilation (D state only)	Permanent Ventilation (E state) – onasemnogene abeparvovec/nusinersen/BSC: Based on a retrospective chart review of SMA patients with tracheotomy or non-invasive ventilation, projected using parametric estimation[13] Not sitting (D state) – onasemnogene abeparvovec: Short term model: AVXS-101-CL-101 [NCT02122952][8] Long term: Projected overall and event-free survival using curve fitted to ENDEAR/SHINE (sham control arm) [NCT02193074, NCT02594124][16,17] nusinersen: Short term model: ENDEAR [NCT02193074][17] and SHINE [NCT02594124][16] Long term: Projected overall and event-free survival using curve fitted to ENDEAR/SHINE (sham control arm) [NCT02193074, NCT02594124][16,17] BSC: ENDEAR (sham control arm)[17] Sitting (C state) – onasemnogene abeparvovec/nusinersen: Parametric curve fitted to overall survival curve for SMA type 2[11] Walking (B state) – onasemnogene abeparvovec/nusinersen: Assume general population mortality in US[29]
Utility Scores	Equivalent to weightings used in the ICER analysis[14], derived from multiple sources Permanent Ventilation: 0.19 Not sitting: 0.19 (BSC) 0.29 (Treatment arms) Sitting: 0.60 (BSC) 0.65 (Treatment arms) Walking: US general population utility
Cost inputs	Price of onasemnogene abeparvovec: $2.125 M one-time dose All other costs were equal to costs used in the ICER analysis[14]
Caregiver disutility (Modified societal perspective)	Equivalent to values used in the ICER analysis[14], derived from The Lewin Group report[30]: Permanent Ventilation: −0.394 Not sitting: −0.2955 Sitting: −0.197 Walking: 0
Lost Household income (Modified societal perspective)	Equivalent to values used in the ICER analysis (estimate 1)[14], derived from The Lewin Group report[30]: SMA early onset: predicted loss $19,833 SMA other: predicted loss $14,800
Non-Medical costs (Modified societal perspective)	Equivalent to values used in the ICER analysis (estimate 1)[14], derived from The Lewin Group report[30]: Permanent ventilation, Not sitting, Sitting: $964 per month
Patient productivity gains	Equivalent to values used in the ICER analysis (estimate 1)[14], derived from The Lewin Group report[30]: Sitting, Walking: potential monthly income $4,540, estimated from age 30–65 years.