SIDE EFFECTS
The most serious adverse
reactions from the use of Femara are:
- Bone effects [see WARNINGS
AND PRECAUTIONS]
- Increases in cholesterol [see WARNINGS
AND PRECAUTIONS]
Because clinical trials are
conducted under widely varying conditions, adverse reactions rates observed in
the clinical trials of a drug cannot be directly compared to rates in the
clinical trials of another drug and may not reflect the rates observed in
practice.
Adjuvant Treatment Of Early Breast
Cancer
The median treatment duration
of adjuvant treatment was 60 months and the median duration of follow-up for
safety was 73 months for patients receiving Femara and tamoxifen.
Certain adverse reactions wer e
prospectively specified for analysis, based on the known pharmacologic
properties and side effect profiles of the two drugs.
Adverse reactions wer e
analyzed irrespective of whether a symptom was present or absent at baseline.
Most adverse reactions reported (approximately 75% of patients reporting 1 or
more AE) were Grade 1 or Grade 2 applying the Common Toxicity Criteria Version
2.0/ Common Terminology Criteria for Adverse Events, version 3.0. Table 1
describes adverse reactions (Grades 1-4) irrespective of relationship to study
treatment in the adjuvant trial for the monotherapy arms analysis (safety
population).
Table 1: Patients with
Adverse Reactions (CTC Grades 1-4, Irrespective of Relationship to Study Drug)
in the Adjuvant Study – Monotherapy Arms Analysis (Median Follow-up 73 Months;
Median Treatment 60 Months)
Adverse Reaction |
Grades 1-4 |
Grades 3-4 |
Femara
N=2448
n (%) |
tamoxifen
N=2447
n (%) |
Femara
N=2448
n (%) |
tamoxifen
N=2447
n (%) |
Pts with any adverse event |
2310 (94.4) |
2214 (90.5) |
635 (25.9) |
604 (24.7) |
Hypercholesterolemia |
1280 (52.3) |
700 (28.6) |
11 ( 0.4) |
6 ( 0.2) |
Hot Flashes/Flushes |
821 (33.5) |
929 (38.0) |
0 - |
0 - |
Arthralgia/Arthritis |
618 (25.2) |
501 (20.4) |
85 ( 3.5) |
50 ( 2.0) |
Night Sweats |
357 (14.6) |
426 (17.4) |
0 - |
0 - |
Bone Fractures2 |
338 (13.8) |
257 (10.5) |
- - |
- - |
Weight Increase |
317 (12.9) |
378 (15.4) |
27 ( 1.1) |
39 ( 1.6) |
Nausea |
283 (11.6) |
277 (11.3) |
6 ( 0.2) |
9 ( 0.4) |
Bone Fractures1 |
247 (10.1) |
174 ( 7.1) |
- - |
- - |
Fatigue (Lethargy, Malaise, Asthenia) |
235 ( 9.6) |
250 (10.2) |
6 ( 0.2) |
7 ( 0.3) |
Myalgia |
217 ( 8.9) |
212 ( 8.7) |
18 ( 0.7) |
14 ( 0.6) |
Edema |
164 ( 6.7) |
160 ( 6.5) |
3 ( 0.1) |
1 ( < 0.1) |
Weight Decrease |
140 ( 5.7) |
129 ( 5.3) |
8 ( 0.3) |
5 ( 0.2) |
Vaginal Bleeding |
128 ( 5.2) |
320 (13.1) |
1 ( < 0.1) |
8 ( 0.3) |
Back Pain |
125 ( 5.1) |
136 ( 5.6) |
7 ( 0.3) |
11 ( 0.4) |
Osteoporosis NOS |
124 ( 5.1) |
66 ( 2.7) |
10 ( 0.4) |
5 ( 0.2) |
Bone pain |
123 ( 5.0) |
109 ( 4.5) |
6 ( 0.2) |
4 ( 0.2) |
Depression |
119 ( 4.9) |
114 ( 4.7) |
16 ( 0.7) |
14 ( 0.6) |
Vaginal Irritation |
111 ( 4.5) |
77 ( 3.1) |
2 ( < 0.1) |
2 ( < 0.1) |
Headache |
105 ( 4.3) |
94 ( 3.8) |
9 ( 0.4) |
5 ( 0.2) |
Pain in extremity |
103 ( 4.2) |
79 ( 3.2) |
6 ( 0.2) |
4 ( 0.2) |
Osteopenia |
87 ( 3.6) |
74 ( 3.0) |
0 - |
2 ( < 0.1) |
Dizziness/Light-Headedness |
84 ( 3.4) |
84 ( 3.4) |
1 ( < 0.1) |
6 (0.2) |
Alopecia |
83 ( 3.4) |
84 ( 3.4) |
0 - |
0 - |
Vomiting |
80 ( 3.3) |
80 ( 3.3) |
3 ( 0.1) |
5 (0.2) |
Cataract |
49 ( 2.0) |
54 ( 2.2) |
16 ( 0.7) |
17 ( 0.7) |
Constipation |
49 ( 2.0) |
71 ( 2.9) |
3 ( 0.1) |
1 ( < 0.1) |
Breast pain |
37 ( 1.5) |
43 ( 1.8) |
1 ( < 0.1) |
0 - |
Anorexia |
20 ( 0.8) |
20 ( 0.8) |
1 ( < 0.1) |
1 ( < 0.1) |
Endometrial Hyperplasia/ Cancer2, 3 |
11/1909 ( 0.6) |
70/1943 ( 3.6) |
- |
- |
Endometrial Proliferation Disorders |
10 (0.3) |
71 (1.8) |
0 - |
14 (0.6) |
Endometrial Hyperplasia/ Cancer1, 3 |
6/1909 ( 0.3) |
57/1943 (2.9) |
- |
- |
Other Endometrial Disorders |
2 ( < 0.1) |
3 ( 0.1) |
0 |
0 |
Myocardial Infarction1 |
24 ( 1.0) |
12 ( 0.5) |
- |
- |
Myocardial Infarction2 |
37 ( 1.5) |
25 (1.0) |
- |
- |
Myocardial Ischemia |
6 ( 0.2) |
9 ( 0.4) |
- |
- |
Cerebrovascular Accident1 |
52 ( 2.1) |
46 ( 1.9) |
- |
- |
Cerebrovascular Accident2 |
70 ( 2.9) |
63 ( 2.6) |
- |
- |
Angina1 |
26 ( 1.1) |
24 ( 1.0) |
- |
- |
Angina2 |
32 ( 1.3) |
31 ( 1.3) |
- |
- |
Thromboembolic Event1 |
51 ( 2.1) |
89 ( 3.6) |
- |
- |
Thromboembolic Event2 |
71 ( 2.9) |
111 ( 4.5) |
- |
- |
Other Cardiovascular1 |
260 (10.6) |
256 (10.5) |
- |
- |
Other Cardiovascular2 |
312 (12.7) |
337 (13.8) |
- |
- |
Second Malignancies1 |
53 ( 2.2) |
78 ( 3.2) |
- |
- |
Second Malignancies2 |
102 ( 4.2) |
119 ( 4.9) |
- |
- |
1During study treatment, based on Safety Monotherapy
population
2Any time after randomization, including post treatment follow-up
3Excluding women who had undergone hysterectomy before study entry
Note: Cardiovascular (including cerebrovascular and thromboembolic), skeletal
and urogenital/endometrial events and second malignancies were collected
life-long. All of these events were assumed to be of CTC Grade 3 to 5 and were
not individually graded. |
When considering all grades
during study treatment, a higher incidence of events was seen for Femara
regarding fractures (10.1% vs 7.1%), myocardial infarctions (1.0% vs 0.5%), and
arthralgia (25.2% vs 20.4%) (Femara vs tamoxifen respectively). A higher
incidence was seen for tamoxifen regarding thromboembolic events (2.1% vs
3.6%), endometrial hyperplasia/cancer (0.3% vs 2.9%), and endometrial
proliferation disorders (0.3% vs 1.8%) (Femara vs tamoxifen respectively).
At a median follow up of 73
months, a higher incidence of events was seen for Femara (13.8%) than for
tamoxifen (10.5%) regarding fractures. A higher incidence was seen for
tamoxifen compared to Femara regarding thromboembolic events (4.5% vs 2.9%),
and endometrial hyperplasia or cancer (2.9% vs 0.4%) (tamoxifen vs Femara,
respectively).
Bone Study: Results of a phase 3 safety trial in 262 postmenopausal
women with resected receptor positive early breast cancer in the adjuvant
setting comparing the effect on lumbar spine (L2-L4) bone mineral density (BMD)
of adjuvant treatment with letrozole to that with tamoxifen showed at 24 months
a median decrease in lumbar spine BMD of 4.1% in the letrozole arm compared to
a median increase of 0.3% in the tamoxifen arm (difference = 4.4%) (P < 0.0001).
No patients with a nor mal BMD at baseline became osteoporotic over the 2 years
and only 1 patient with osteopenia at baseline (T score of -1.9) developed
osteoporosis during the treatment period (assessment by central review). The
results for total hip BMD were similar, although the differences between the
two treatments were less pronounced. During the 2 year period, fractures were
reported by 4 of 103 patients (4%) in the letrozole arm, and 6 of 97 patients
(6%) in the tamoxifen arm.
Lipid Study: In a phase 3 safety trial in 262 postmenopausal women with
resected receptor positive early breast cancer at 24 months comparing the effects
on lipid profiles of adjuvant letrozole to tamoxifen, 12% of patients on
letrozole had at least one total cholesterol value of a higher CTCAE grade than
at baseline compared with 4% of patients on tamoxifen.
Extended Adjuvant Treatment Of Early
Breast Cancer, Median Treatment Duration Of 24 Months
The median duration of extended
adjuvant treatment was 24 months and the median duration of follow-up
for safety was 28 months for patients receiving Femara and placebo.
Table 2 describes the adverse
reactions occurring at a frequency of at least 5% in any treatment group during
treatment. Most adverse reactions reported were Grade 1 and Grade 2 based on
the Common Toxicity Criteria Version 2.0. In the extended adjuvant setting, the
reported drug-related adverse reactions that were significantly different from
placebo were hot flashes, arthralgia/arthritis, and myalgia.
Table 2: Percentage of
Patients with Adverse Reactions
|
Number (%) of Patients with Grade 1-4 Adverse Reaction |
Number (%) of Patients with Grade 3-4 Adverse Reaction |
Femara
N=2563 |
Placebo
N=2573 |
Femara
N=2563 |
Placebo
N=2573 |
Any Adverse Reaction |
2232 (87.1) |
2174 (84.5) |
419 (16.3) |
389 (15.1) |
Vascular Disorders |
1375 (53.6) |
1230 (47.8) |
59 (2.3) |
74 (2.9) |
Flushing |
1273 (49.7) |
1114 (43.3) |
3 (0.1) |
0 |
General Disorders |
1154 (45) |
1090 (42.4) |
30 (1.2) |
28 (1.1) |
Asthenia |
862 (33.6) |
826 (32.1) |
16 (0.6) |
7 (0.3) |
Edema NOS |
471 (18.4) |
416 (16.2) |
4 (0.2) |
3 (0.1) |
Musculoskeletal Disorders |
978 (38.2) |
836 (32.5) |
71 (2.8) |
50 (1.9) |
Arthralgia |
565 (22) |
465 (18.1) |
25 (1) |
20 (0.8) |
Arthritis NOS |
173 (6.7) |
124 (4.8) |
10 (0.4) |
5 (0.2) |
Myalgia |
171 (6.7) |
122 (4.7) |
8 (0.3) |
6 (0.2) |
Back Pain |
129 (5) |
112 (4.4) |
8 (0.3) |
7 (0.3) |
Nervous System Disorders |
863 (33.7) |
819 (31.8) |
65 (2.5) |
58 (2.3) |
Headache |
516 (20.1) |
508 (19.7) |
18 (0.7) |
17 (0.7) |
Dizziness |
363 (14.2) |
342 (13.3) |
9 (0.4) |
6 (0.2) |
Skin Disorders |
830 (32.4) |
787 (30.6) |
17 (0.7) |
16 (0.6) |
Sweating Increased |
619 (24.2) |
577 (22.4) |
1 ( |