Table 3

Summary of primary and secondary efficacy results for bone-turnover markers in the evaluable population

Bone-turnover marker
Exemestane (n = 19)
Letrozole (n = 19)
Anastrozole (n = 16)
Placebo (n = 20)

Primary efficacy measure: percentage change from baseline to week 24*
     BAP
3.0 (-11, 24)
-0.58 (-9.4, 7.1)
-4.5 (-7.0, 4.5)
-0.88 (-11.8, 8.1)
     S-CTx
21 (6.9, 34)
31 (12, 69)
9.3 (-7.7, 34)
12 (-8.7, 26)
     PINP
24 (11, 30)
5.7 (-1.1, 12)
6.3 (-9.3, 19)
6.1 (-11, 16)
     U-CTx
22 (10, 35)
34 (19, 74)
1.7 (-5.6, 29)
15 (1.5, 29)
     U-NTx
-8.5 (-30, 1.9)
10 (-1.5, 20)
-1.5 (-26, 24)
1.7 (-13, 19)
Secondary efficacy measure: percentage change from baseline to week 12*
     BAP
-1 (-5.7, 8.0)
-4.3 (-7.5, 7.3)
-7.3 (-17, 3.7)
-0.99 (-6.0, 3.3)
     S-CTx
18 (10, 37)
18 (7.2, 39)
8.0 (-9.6, 22)
8.3 (2.9, 19)
     PINP
19 (-1.1, 34)
-0.29 (-5.9, 7.2)
0.92 (-7.4, 7.1)
4.1 (-12, 21)
     U-CTx
20 (4.7, 38)
14 (8.4, 24)
2.9 (-13, 9.0)
8.8 (2.0, 13)
     U-NTx
6.8 (1.1, 23)
0.21 (-12, 4.2)
-2.3 (-15, 22)
-0.36 (-13, 19)
Secondary efficacy measure: percentage change from baseline to week 36*
     BAP
5.6 (3.7, 26)
15 (1.7, 29)
1.4 (-6.3, 6.6)
-1.9 (-10, 6.9)
     S-CTx
13 (-2.2, 34)
30 (22, 52)
9.2 (-13.5, 22)
13 (1.2, 19)
     PINP
15 (-0.14, 39)
24 (-0.33, 56)
10 (0.47, 25)
-0.92 (-16, 22)
     U-CTx
17 (-5.8, 43)
46 (26, 70)
7.4 (-28, 29)
23 (1.1, 39)
     U-NTx
-6.3 (-20, 5.1)
11 (-1.3, 34)
-1.4 (-14, 46)
6.5 (-6, 26)
Secondary efficacy measure: AUC0–12 week*
     BAP, ng/ml × week
1.6 (-2.0, 10)
-3.7 (-8.6, 2.3)
-5.8 (-26, 3.2)
-1.7 (-9.0, 5.7)
     S-CTx, ng/ml × week
0.68 (0.52, 1.37)
0.60 (0.28, 0.99)
0.33 (-0.28, 0.73)
0.38 (0.085, 0.65)
     PINP, ng/ml × week
42 (25, 73)
-10 (-47, 23)
-11 (-31, 20)
19 (-24, 56)
     U-CTx(adjusted), μg/mmol Cr × week
269 (-173, 553)
302 (53, 643)
-242 (-762, 192)
105 (-129, 396)
     U-NTx(adjusted), nmol BCE/mmol Cr × week
49 (-2.4, 91)
50 (15, 81)
-6.5 (-49, 30)
0.67 (-92, 42)
Secondary efficacy measure: AUC0–24 week*
     BAP, ng/ml × week
17 (-3.7, 29)
-14 (-23, 8.1)
-14 (-55, 9.2)
0.31 (-26, 12)
     S-CTx, ng/ml × week
2.0 (1.3, 2.9)
1.5 (1.1, 2.3)
1.0 (-0.41, 1.8)
0.89 (0.046, 1.6)
     PINP, ng/ml × week
187 (95, 295)
-6.1 (-57, 79)
19 (-46, 90)
42 (-67, 142)
     U-CTx(adjusted), μg/mmol Cr × week
1063 (170, 1868)
1157 (422, 2314)
61 (-1077, 588)
427 (51, 751)
     U-NTx(adjusted), nmol BCE/mmol Cr × week
21 (-64, 176)
102 (-49, 210)
-9.0 (-204, 158)
-47 (-265, 58)

*All data are medians (bias-corrected and adjusted 95% bootstrap confidence interval).

AUC, area under the curve; BAP, bone alkaline phosphatase; BCE, bone collagen equivalent; Cr, creatinine; PINP, procollagen type I N-terminal peptide; S-CTx, serum C-terminal telopeptide of type I collagen; U-CTx, urinary C-terminal telopeptide of type I collagen; U-NTx, urinary N-terminal telopeptide of type I collagen.

Goss et al. Breast Cancer Research 2007 9:R52   doi:10.1186/bcr1757