Table 2. Budget Impact Model Results for Avapritinib for a 1-Million Member Health Plan by Cost Type^a.

Model	Value
	Year 1	Year 2	Year 3
GIST, PDGFRA exon 18, and fourth-line treatment
Eligible patients, No.	1.22	1.24	1.26
Total cost, $
With avapritinib available	96 157	133 403	177 809
Without avapritinib available	51 120	56 646	62 205
Incremental budget impact
Total, $	45 038	76 758	115 604
Owing to change in postprogression costs, $b	−454	−1999	−3607
PMPM	0.004	0.006	0.010
GIST and PDGFRA exon 18
Eligible patients, No.	0.07	0.08	0.09
Total cost, $
With avapritinib available	19 200	41 398	65 636
Without avapritinib available	8192	13 461	18 761
Incremental budget impact
Total, $	11 007	27 937	46 875
Owing to change in postprogression costs, $b	−610	−2224	−3924
PMPM	0.001	0.002	0.004
GIST and fourth-line treatment
Eligible patients, No.	1.15	1.16	1.17
Total cost, $
With avapritinib available	78 203	93 408	113 735
Without avapritinib available	44 024	44 288	44 553
Incremental budget impact
Total, $	34 179	49 121	69 182
Owing to change in postprogression costs, $b	157	225	317
PMPM	0.003	0.004	0.006

Abbreviations: GIST, gastrointestinal stromal tumors; PDGFRA, platelet-derived growth factor receptor alpha; PMPM, per member per month.

^a The health plan population mix was 69% commercial, 22% Medicare, and 9% Medicaid.

^b Postprogression costs that have been avoided or delayed.