Pharmacological properties of the drug Arimidex
A powerful and highly selective aromatase inhibitor. In postmenopausal women, estradiol is mainly produced by the conversion of androstenedione to estrone in peripheral tissues with the participation of the aromatase enzyme, then estrone is converted to estradiol. Reducing the level of estradiol in the blood has a therapeutic effect in women with breast cancer. In postmenopausal women, anastrozole in a daily dose of 1 mg causes a decrease in the level of estradiol in the blood by 80%. Does not have progestogenic or androgenic activity. At a dose of up to 10 mg/day, it has no effect on the secretion of cortisol and aldosterone, including in the standard test with ACTH stimulation. Corticosteroid replacement is not required when using anastrozole. In a phase 3 study of 9,366 postmenopausal women with operable breast cancer treated for 5 years, anastrozole was superior to tamoxifen in terms of disease-free survival. Significantly greater disease-free survival benefits were observed for anastrozole compared with tamoxifen in individuals positive for a particular hormone receptor. Anastrozole was superior to tamoxifen in terms of time to relapse and long-term relapse. The incidence of contralateral breast cancer was lower with anastrozole compared with tamoxifen. At 5 years, anastrozole is as effective as tamoxifen for overall survival. However, due to the low mortality rates, additional monitoring is required to more accurately determine long-term survival rates with anastrozole compared with tamoxifen. Summary table of extreme indicators in the ATAC study: analysis at the end of treatment that lasted 5 years
Extreme performance indicators | Number of cases (frequency) | |||
Patients who intended to be treated | Hormone receptor positive tumor status | |||
Anastrozole (N=3125) | Tamoxifen (N=3116) | Anastrozole (N=2618) | Tamoxifen (N=2598) | |
| Disease-free survival a | 575 (18,4) | 651 (20,9) | 424 (16,2) | 497 (19,1) |
| Risk factor | 0,87 | 0,83 | ||
| 2-sided 95% CI | 0,78–0,97 | 0,73–0,94 | ||
| p-value | 0,0127 | 0,0049 | ||
| Long-term disease-free survival b | 500 (16,0) | 530 (17,0) | 370 (14,1) | 394 (15,2) |
| Risk factor | 0,94 | 0,93 | ||
| 2-sided 95% CI | 0,83–1,06 | 0,80–1,07 | ||
| p-value | 0,2850 | 0,2838 | ||
| Time until relapse c | 402 (12,9) | 498 (16,0) | 282 (10,8) | 370 (14,2) |
| Risk factor | 0,79 | 0,74 | ||
| 2-sided 95% CI | 0,70–0,90 | 0,64–0,87 | ||
| p-value | 0,0005 | 0,0002 | ||
| Time to distant relapse d | 324 (10,4) | 375 (12,0) | 226 (8,6) | 265 (10,2) |
| Risk factor | 0,86 | 0,84 | ||
| 2-sided 95% CI | 0,74–0,99 | 0,70–1,00 | ||
| p-value | 0,0427 | 0,0559 | ||
| Primary/contralateral cancer | 35 (1,1) | 59 (1,9) | 26 (1,0) | 54 (2,1) |
| Difference coefficient | 0,59 | 0,47 | ||
| 2-sided 95% CI | 0,39–0,89 | 0,30–0,76 | ||
| p-value | 0,0131 | 0,0018 | ||
| Overall survival e | 411 (13,2) | 420 (13,5) | 296 (11,3) | 301 (11,6) |
| Risk factor | 0,97 | 0,97 | ||
| 2-sided 95% CI | 0,85–1,12 | 0,83–1,14 | ||
| p-value | 0,7142 | 0,7339 | ||
- Disease-free survival includes all cases of recurrence and is defined as the first episode of locoregional recurrence, contralateral cancer of the other breast, distant recurrence, or death (from any cause).
- Long-term disease-free survival is defined as the first episode of distant relapse or death (from any cause).
- Time to recurrence was defined as the first episode of locoregional recurrence, contralateral cancer of the other breast, distant recurrence, or death due to breast cancer.
- Time to distant recurrence is defined as the first episode of distant recurrence or death due to breast cancer.
- Number (%) of deaths.
As with other treatment decisions, women with breast cancer and their doctor must weigh the relative benefits and risks of treatment. When anastrozole and tamoxifen were coadministered, their efficacy and safety were similar to tamoxifen, regardless of hormone receptor status. This is believed to be due to a decrease in the degree of inhibition of estadiol, an effect that anastrozole exhibits. Adjuvant therapy for early stage breast cancer in patients receiving adjuvant therapy with tamoxifen After a median follow-up of 24 months in a phase III study (ABCSG 8), which included 2579 patients with hormone receptor-positive early breast cancer and who were surgical intervention was performed without radiotherapy and chemotherapy, disease-free survival rates in the group that switched to anastrozole after 2 years of adjuvant tamoxifen therapy were the same as in the group that remained on tamoxifen treatment. Time to any relapse, time to local or distant relapse, and time to distant relapse confirmed the benefit of anastrozole, consistent with disease-free survival results. The incidence of contralateral breast cancer was very low in the two treatment groups, with a quantitative advantage favoring anastrozole. Overall survival was similar in the two treatment groups. Summary table of extremes and results in the ABCSG 8 study
Extreme performance indicators | Number of cases (frequency) | |
Anastrozole, n=1297 | Tamoxifen, n=1282 | |
| Disease-free survival | 65 (5,0) | 93 (7,3) |
| Risk factor | 0,67 | |
| 2-sided 95% CI | 0,49–0,92 | |
| p-value | 0,014 | |
| Time until any relapse occurs | 36 (2,8) | 66 (5,1) |
| Risk factor | 0,53 | |
| 2-sided 95% CI | 0,35–0,79 | |
| p-value | 0,002 | |
| Time to local or distant recurrence | 29 (2,2) | 51 (4,0) |
| Risk factor | 0,55 | |
| 2-sided 95% CI | 0,35 — 0,87 | |
| p-value | 0,011 | |
| Time to distant relapse | 22 (1,7) | 41 (3,2) |
| Risk factor | 0,52 | |
| 2-sided 95% CI | 0,31–0,88 | |
| p-value | 0,015 | |
| New contralateral breast cancer | 7 (0,5) | 15 (1,2) |
| Risk factor | 0,46 | |
| 2-sided 95% CI | 0,19–1,13 | |
| p-value | 0,090 | |
| Overall survival | 43 (3,3) | 45 (3,5) |
| Risk factor | 0,96 | |
| 2-sided 95% CI | 0,63–1,46 | |
| p-value | 0,840 | |
Two further clinical trials (GABG/ARNO 95 and ITA), one of which involved surgery and chemotherapy, and a combined analysis of the ABCSG 8 and GABG/ARNO 95 studies support these results. The safety profile of anastrozole in these 3 studies was consistent with the safety profile for women with hormone receptor-positive early breast cancer. Pharmacokinetics : Rapidly absorbed after oral administration, maximum plasma concentration is achieved within 2 hours when taken on an empty stomach. Concomitant food intake slightly reduces the rate, but not the extent, of absorption. Approximately 90–95% of the equilibrium concentration is achieved after 7 days from the start of administration. The pharmacokinetics of anastrozole does not depend on the age of postmenopausal women. The pharmacokinetics of anastrozole in children have not been studied. 40% of anastrozole binds to plasma proteins. The half-life is 40–50 hours. Anastrozole is extensively metabolized in postmenopausal women, less than 10% of the dose is excreted unchanged in the urine within 72 hours. Metabolized through N-dealkylation, hydroxylation and glucuronidation. Metabolites are excreted mainly in the urine. Triazole, the main metabolite detected in plasma and urine, is not an aromatase inhibitor. The clearance of anastrozole after oral administration in persons with compensated liver cirrhosis or impaired renal function does not differ from the clearance in healthy volunteers.
Indications for use of the drug Arimidex
Treatment of advanced breast cancer in postmenopausal women, excluding patients with estrogen-negative cancer, unless they have previously had a positive clinical response to tamoxifen. Adjuvant treatment of invasive estrogen-positive breast cancer in the early stages in postmenopausal patients. Adjuvant treatment of estrogen-positive breast cancer in the early stages in postmenopausal patients who have received adequate tamoxifen therapy for 2–3 years.
Antitumor drug Arimidex - reviews
Valentina Kirillovna
https://med-otzyv.ru/lekarstva/143-a/20313-arimideks
My elderly aunt is taking Arimidex for left breast cancer. He helps her a lot. The problem is that they give it to her for free every other time, all the time it is not in the pharmacy when she wants to get it with a free prescription at the dispensary pharmacy. And one package costs from 4, 5 to 5 thousand rubles. This is half of her pension. So much for free healthcare!
AntonK
https://forum.steelfactor.ru/index.php?showtopic=17882
Arimidex is a great teacher! Estrogen presses very hard and quickly. Here, as I already wrote, the original costs 120 Euros for 28 tabs of 1 mg and from underground German companies 25 Euros for 25 capsules of 2 mg.
I took 25 tabs for 25 Euros. Naturally working!
Last Friday I had a blood test for test and estradiol. So, I took Arimidex for a week before the test and my estrodiol levels dropped very significantly! The doctor was surprised at my level! biggrin. gif Norm 6 - 50 I have 8 rolleyes. gif Arimidex works as it should! Testosterone is also absolutely normal. The norm is 3 - 6, I have 4, 5. A month has passed since the last course.
before the last course, the estradiol level was 40 when the norm was 6 - 50, but after the course it was very high. Right now only 8 after a week of taking it! I took 2 mg every other day.
It’s not for nothing that the pros eat Arimidex during courses so that it doesn’t flood...
Anton Sytnik
https://www.piluli.ru/product/Arimideks/review
Surprisingly, but true - men also indulge in Arimidex, I didn’t take the risk myself, but I saw the results of my fellow exercisers - testosterone levels are off the charts, body contour is super and in a very short time, but there is a flip side to the coin, I’m a doctor and I know, suppression estrogen leads to impotence, problems with the heart and brain, you can overdo it and stupid quality is your middle name :)))
Natalia Obolentseva
https://www.piluli.ru/product/Arimideks/review
Breast cancer was found with the onset of menopause. They did not perform the operation because it was complicated by the fact that the cancer was hormone-positive; they decided to treat it with drugs and immediately prescribed Arimidex. I had to undergo a bunch of tests, which is mandatory for such chemistry. The growth of the tumor has decreased significantly, it has shrunk and I am preparing for surgery to remove it. The drug did not cause any serious consequences for the body.
Oksana
https://www.medcentre.com.ua/medicamenty/arimideks.html
Arimidex is better tolerated than other similar drugs. It was prescribed to my grandmother (70 years old). She has breast cancer. It was true that there was nausea. But such a medicine cannot be without side effects. The doctor praised Arimidex. Although, we found out that now only it is supplied to dispensaries, so maybe they praise it. On the other hand, what to do? In addition, my grandmother said that Arimidex seemed to suit her well. At least there are no creepy side effects.
Lyudmila
https://zhenskay-pilulya.info/drugie/arimideks
“If you want your hormone levels to be normal after surgery on the uterus, fallopian tube or other genital organs, then take the drug Arimidex, as I did. I read a lot of reviews, then I went for a consultation and they gave me a prescription. I’ve been drinking under the supervision of a doctor for almost six months, but so far everything is fine, I don’t complain about my health and it’s all thanks to Arimidex tablets! »
Side effects of Arimidex
The following adverse events may occur while taking anastrozole:
Very common (≥10%) | Vascular | Hot flashes, mostly mild to moderate |
Often (1–10%) | Are common | Asthenia, mostly mild or moderate |
| Musculoskeletal, connective tissue and bone | Joint pain/decreased mobility, mostly mild to moderate | |
| Reproductive system and mammary gland | Vaginal dryness, mostly mild to moderate | |
| Skin and subcutaneous tissue | Thinning hair, mostly mild to moderate Rash, mostly mild to moderate | |
| Gastrointestinal | Nausea, mostly mild to moderate Diarrhea, mostly mild to moderate | |
| Nervous system | Headache, mostly mild to moderate | |
Uncommon (0.1–1%) | Reproductive system and mammary gland | Vaginal bleeding, mostly mild to moderate* |
| Metabolism and nutrition | Anorexia, mostly mild | |
| Gastrointestinal | Hypercholesterolemia, mostly mild to moderate Vomiting, mostly mild to moderate | |
| Nervous system | Drowsiness, mostly mild to moderate | |
Very rare (≤0.01%) | Skin and subcutaneous tissue | Erythema multiforme Stevens-Johnson syndrome Allergic reactions, including angioedema, urticaria and anaphylaxis |
*Vaginal bleeding occurred infrequently, mainly in patients with advanced breast cancer during the first few weeks after changing hormonal therapy to anastrozole treatment. If bleeding continues, the patient must be examined further. Because anastrozole reduces circulating estrogen levels, it may cause a decrease in bone mineral density, which increases the risk of fractures in some patients. Elevations of γ-glutamine transferase and alkaline phosphatase have been reported infrequently (≥0.1% and ≤1%). The cause of these changes has not been established. The table shows the frequency of prespecified side effects that were noted in the ATAC study, regardless of the cause of their occurrence. These side effects were observed in patients who received study therapy up to 14 days after discontinuation of treatment.
Side effects | Anastrozole, n=3092 | Tamoxifen, n=3094 |
| Tides | 1104 (35,7%) | 1264 (40,9%) |
| Joint pain/impaired mobility | 1100 (35,6%) | 911 (29,4%) |
| Mood disorder | 597 (19,3%) | 554 (17,9%) |
| Weakness/asthenia | 575 (18,6%) | 544 (17,6%) |
| Nausea and vomiting | 393 (12,7%) | 384 (12,4%) |
| Fractures | 315 (10,2%) | 209 (6,8%) |
| Fractures of the spine, hip or wrist/Colles | 133 (4,3%) | 91 (2,9%) |
| Wrist/Colles Fractures | 67 (2,2%) | 50 (1,6%) |
| Spinal fractures | 43 (1,4%) | 22 (0,7%) |
| Hip fractures | 28 (0,9%) | 26 (0,8%) |
| Cataract | 182 (5,9%) | 213 (6,9%) |
| Vaginal bleeding | 167 (5,4%) | 317 (10,2%) |
| Cardiac ischemia | 127 (4,1%) | 104 (3,4%) |
| Angina pectoris | 71 (2,3%) | 51 (1,6%) |
| Myocardial infarction | 37 (1,2%) | 34 (1,1%) |
| Coronary artery diseases | 25 (0,8%) | 23 (0,7%) |
| Myocardial ischemia | 22 (0,7%) | 14 (0,5%) |
| Vaginal discharge | 109 (3,5%) | 408 (13,2%) |
| Various types of venous thromboembolism | 87 (2,8%) | 140 (4,5%) |
| Deep venous thromboembolism, including PE | 48 (1,6%) | 74 (2,4%) |
| Ischemic cerebrovascular diseases | 62 (2,0%) | 88 (2,8%) |
| Endometrial cancer | 4 (0,2%) | 13 (0,6%) |
After a median follow-up of 68 months, the incidence of fractures in the anastrozole and tamoxifen groups was 22 per 1000 patient-years and 15 per 1000 patient-years, respectively. The number of fractures in the anastrozole group is similar to that observed in age-matched postmenopausal women. The incidence of osteoporosis was 10.5% in patients treated with anastrozole and 7.3% in patients treated with tamoxifen.
Arimidex®
Incidence rates were calculated from the number of adverse events observed in a phase III study in 9366 postmenopausal women with operable breast cancer treated for 5 years, with the incidence of adverse events in the comparison groups and the investigator's opinion regarding the dependence of the adverse event on the study drugs are not taken into account.
Determination of the frequency of adverse reactions: very often (more than or equal to 10%); often (from 1 to less than 10%); uncommon (from 0.1 to less than 1%); rare (from 0.01 to less than 0.1%); very rare (less than 0.01%).
From the side of blood vessels
: very often - “hot flashes”.
From the musculoskeletal and connective tissue side
: very often - arthralgia / joint stiffness, arthritis, often - bone pain, myalgia, infrequently - trigger finger.
From the genital organs and breast
: often - dryness of the vaginal mucosa; vaginal bleeding (mainly during the first weeks after discontinuation or change of previous hormonal therapy to Arimidex®).
From the skin and subcutaneous tissues
: very often - skin rash, often - thinning hair (alopecia), allergic reactions, infrequently - urticaria, rarely - erythema multiforme, anaphylactoid reaction, cutaneous vasculitis (including isolated cases of purpura (Henoch-Schönlein syndrome)), very rarely - Stevens syndrome -Johnson, angioedema.
From the gastrointestinal tract
: very often - nausea, often - diarrhea, vomiting.
From the liver and biliary tract
: often - increased activity of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase; infrequently - increased activity of gamma-glutamyltransferase and bilirubin concentration, hepatitis.
From the nervous system
: very often - headache, often - drowsiness, carpal tunnel syndrome (mainly observed in patients with risk factors for this disease), sensitivity disorders (including paresthesia, loss or distortion of taste).
Metabolism and nutrition
: often - anorexia, hypercholesterolemia, infrequently - hypercalcemia (with or without increased concentrations of parathyroid hormone). Taking the drug may cause a decrease in bone mineral density due to a decrease in the concentration of circulating estradiol, thereby increasing the risk of osteoporosis and bone fractures.
General disorders
: very often - mild or moderate asthenia.
Adverse events noted during clinical studies not related to taking the drug Arimidex®: anemia, constipation, dyspepsia, back pain, abdominal pain, increased blood pressure, increased body weight, depression, insomnia, dizziness, anxiety, paresthesia.
Special instructions for the use of Arimidex
Not recommended for use in children. The onset of menopause should be confirmed by biochemical studies in case of doubt about the patient's hormonal status. There are no data on the safety of the use of anastrozole for the treatment of patients with moderate to severe hepatic impairment and patients with severe renal impairment (creatinine clearance below 20 ml/min). There are no data regarding the use of anastrozole with LH-RH analogues. In patients with osteoporosis or at risk of osteoporosis, bone mineral density should be assessed by bone densitometry, such as a DEXA scan, at the start of treatment and regularly during treatment. If necessary, treatment or prevention of osteoporosis should be prescribed and the patient's condition should be monitored. Because anastrozole reduces circulating estrogen levels, it may result in decreased bone mineral density. There is currently insufficient evidence regarding the beneficial effects of bisphosphonates on anastrozole-induced bone mineral loss or their benefit when used prophylactically. Pregnancy and breastfeeding. The use of the drug is contraindicated during these periods. Impact on the ability to drive a car and operate machinery. It is unlikely that anastrozole affects this ability, however, given reports of asthenia and drowsiness associated with the use of the drug, a balanced approach to driving and operating machinery is recommended.
