Corroboration of claims algorithm for second-line costs of metastatic colorectal cancer treatment with targeted agents

Figures & data

Figure 1. Sample selection.

Table 1. Patient demographic and clinical characteristics.

	Second-line therapy cohort				p-value
	Bevacizumab (n = 450)		Cetuximab (n = 119)
	Mean	SD	Mean	SD
Age, years^a	61.22	12.18	61.41	12.55	0.878
Charlson comorbidity score^b	6.90	1.76	6.92	1.78	0.930
6-month^b total, all cause healthcare costs, $	58,313	62,013	69,480	77,946	0.370
	n	%	n	%
Index year
2008	85	18.89	24	20.17	0.753
2009	151	33.56	33	27.73	0.227
2010	116	25.78	32	26.89	0.806
2011	98	21.78	30	25.21	0.425
Male	256	56.89	74	62.18	0.298
Coverage type
Commercial	318	70.67	84	70.59	0.987
Medicare Advantage	132	29.33	35	29.41	0.987
Type of benefit plan
Health Maintenance Organization (HMO)	113	25.34	30	25.21	0.978
Indemnity Health Plan (IND)	9	2.02	3	2.52	0.735
Point of Service (POS)	219	49.10	54	45.38	0.470
Preferred Provider Organization (PPO)	45	10.09	11	9.24	0.784
Exclusive Provider Organization (EPO)	29	6.50	12	10.08	0.181
Other	31	6.95	9	7.56	0.817
Geographic region
Northeast	20	4.44	13	10.92	0.007
Midwest	150	33.33	40	33.61	0.954
South	238	52.89	54	45.38	0.145
West	42	9.33	12	10.08	0.804

^aAs of index date.

^bDuring 6 month period prior to 2nd line therapy.

Table 2. Match rate between claims-based algorithm and medical chart review for evidence of two lines of therapy.

Algorithm	Claims (n)	Chart (n)	Chart and claims (n)	Match rate (%)	95% CI
Initial
Evidence of 2 LOT, n	92	63	63	68.5%	58.0–77.8
Second LOT contained bevacizumab or aEGFR	92	54	46	50.0%	39.4–60.6
Bevacizumab	69	35	32	46.4%	34.3–58.8
aEGFR	23	19	14	60.9%	38.5–80.3
Final
Evidence of 2 LOT, n	61	52	52	85.3%	73.8–93.0
Second LOT contained bevacizumab or aEGFR	61	48	44	72.1%	59.2–82.9
Bevacizumab	42	32	30	71.4%	55.4–84.3
aEGFR	19	16	14	73.7%	48.8–90.9
Cetuximab	15	12	10	66.7%	38.4–88.2
Panitumumab	4	4	4	100.0%	39.8–100
Sensitivity analysis
Evidence of 2 LOT, n	44	43	43	97.7%	88.0–99.9
Second LOT contained bevacizumab or aEGFR	44	39	36	81.8%	67.3–91.8
Bevacizumab	28	24	23	82.1%	63.1–93.9
aEGFR	16	15	13	81.3%	54.4–96.0
Cetuximab	12	11	9	75.0%	42.8–94.5
Panitumumab	4	4	4	100.0%	39.8–100

aEGFR, anti-epidermal growth factor receptor; CI, confidence interval.

Table 3. First- and second-line treatment patterns.

	Second-line therapy cohort		p-value
	Bevacizumab (n = 450)	Cetuximab (n = 119)
First-line treatment pattern
First-line regimens, n (%)
Irinotecan-based	91 (20.2)	34 (28.6)	0.05
Oxaliplatin-based	265 (58.9)	59 (49.6)	0.68
5-FU/capecitabine-based	412 (91.6)	96 (80.7)	<0.001
5-FU-based	329 (73.1)	86 (72.3)	0.85
Capecitabine-based	102 (22.7)	17 (14.3)	0.05
Bevacizumab containing	348 (77.3)	72 (60.5)	<0.001
Cetuximab containing	14 (3.1)	32 (26.9)	<0.001
First-line therapy duration, days, mean (SD)	131.1 (116.8)	147.8 (155.5)	0.27
First-line therapy duration, days, median	105.5	99.0
Second-line treatment pattern
Second-line regimens, n (%)
Irinotecan-based	210 (46.7)	87 (73.1)	<0.001
Oxaliplatin-based	165 (36.7)	6 (5.0)	<0.001
5-FU/capecitabine-based	366 (81.3)	38 (31.9)	0.01
5-FU-based	320 (71.1)	35 (29.4)	<0.001
Capecitabine-based	80 (17.8)	7 (5.9)	0.01
Monotherapy	45 (10.0)	21 (17.7)	<0.001
Second-line therapy duration, days, mean (SD)	122.7 (112.2)	123.3 (128.3)	0.96
Second-line therapy duration, days, median	85.5	86.0
Patients with censored second-line therapy^a	108 (24.0)	31 (26.1)	0.64
Patients who died within 28 days of last observed drug administration during second-line therapy^a	14 (3.1)	5 (4.2)	0.57

^aSecond-line therapy was considered censored if patients survived more than 30 days after the last observed claim in the second-line of therapy which was less than 3 months prior to disenrolment or end of the study period with no evidence of initiating a third line therapy.

Figure 2. (a) Mean total healthcare costs during second-line therapy. Adjusted (ADJ) and unadjusted difference (DIFF) in mean total healthcare costs between cohorts. Adjusted costs are based on the multivariate GLM model. Medical costs represent inpatient, hospital outpatient, office, emergency room, and other medical services. (b) Mean total chemotherapy and targeted agent costs during second-line therapy. Adjusted (ADJ) and unadjusted difference (DIFF) in mean chemotherapy and targeted agent costs between cohorts. Adjusted costs are based on the multivariate GLM model. Costs include all infusion costs that occurred on the same day as the claims for the drugs.

Figure 3. (a) Mean monthly (PPPM) healthcare costs during second-line therapy. Adjusted (ADJ) and unadjusted difference (DIFF) in mean total healthcare costs between cohorts. Adjusted costs are based on the multivariate GLM model. Medical costs represent inpatient, hospital outpatient, office, emergency room, and other medical services. (b) Mean monthly (PPPM) chemotherapy and targeted agent costs during second-line therapy. Adjusted (ADJ) and unadjusted difference (DIFF) in mean chemotherapy and targeted agent costs between cohorts. Adjusted costs are based on the multivariate GLM model. Costs include all infusion costs that occurred on the same day as the claims for the drugs.