by itself. The new regimen also is superior than irinotecan on five of the six side effect measures.
In Figure 2 we plot the mean regimen price by quarter by multiplying the market share of each regimen by the price physicians paid for that regimen. Since we do not observe prices for the outside option, regimen market shares are rescaled to equal one once the outside option is omitted. The price to physicians of a 24-week 5-FU/LV regimen in the first quarter of 1993 was $127. The mean price of colorectal cancer drugs increased to $597 in the first quarter of 1998 when two new irinotecan-based regimens first appeared in the SEER data set.18 In the first quarter of 1998, physicians paid $16,806 for a 24-week regimen of irinotecan and $15,944 for a 24-week regimen of irinotecan + 5-FU/LV. Mean prices rose sharply between 1998 and 2001 as the market share of the irinotecan-based regimens increased and capecitabine was launched (see Figure 1). Most of the increase was due to patients being shifted to the irinotecan-based regimens (see Figure 1) rather than increases in the prices of the new regimens once they were launched. The mean regimen price increased by 848 percent between the first quarter of 1998 and the first quarter of 2001, whereas the prices of the two irinotecan-based regimens increased by 24 percent and 22 percent during the same time period.
The mean regimen price increased from $8,503 in the third quarter of 2002 to $12,664 in the third quarter of 2003 (a 49 percent increase), to $26,811 in the third quarter of 2004 (a 112 percent increase from 2003), and finally to $36,291 in the third quarter of 2005 (a 35 percent increase from 2004). The prices of the three regimens with the largest market shares in the third quarter of 2005 were bevacizumab + oxaliplatin + 5-FU (price of $76,636 and 18.9 percent market
18Irinotecan began generating sales in the IMS Health data set in the second quarter of 1996. However, Medicare claims recorded irinotecan in an ”other” category until the first quarter of 1998.