Buy Arimidex Online
What is Arimidex?
Arimidex (Anastrozole) reduces estrogen levels in postmenopausal women, which can slow the growth of certain types of breast tumors that need estrogen to grow in the body.
Arimidex is used to treat breast cancer in postmenopausal women. It is often given to women whose cancer progresses even after taking tamoxifen (Nolvadex, Soltamox). International clinical trials have shown that this drug prevents relapses in 80 percent of patients who had their primary foci of cancer tumors removed in a timely manner.
A wide range of indications allows the use of Arimidex in hormone-positive breast cancer in postmenopausal patients both in initial adjuvant therapy after surgical treatment, in adjuvant therapy after 2-3 years of tamoxifen therapy, and in the first and second lines of therapy for locally advanced and metastatic breast cancer.
Arimidex can also be used for purposes not specified in this manual.
Before taking this medicine
You should not use Arimidex if you are allergic to anastrozole, if you are breastfeeding, or if you have not finished menopause yet. Arimidex is not intended for men and children.
To make sure Arimidex is safe for you, tell your doctor if you have:
- Heart disease;
- Circulation problems;
- History of stroke or blood clot;
- Severe liver disease;
- high cholesterol;
- Osteoporosis or low bone mineral density.
Arimidex may decrease bone mineral density, which may increase the risk of osteoporosis. Your bone mineral density may need to be tested before and during anastrozole treatment.
Although it is unlikely that a postmenopausal woman will be pregnant, anastrozole can harm the unborn child. Do not take this medicine if you are pregnant or may become pregnant. Use effective birth control if you haven't gone through menopause, and tell your doctor right away if you get pregnant during treatment.
It is not known whether anastrozole passes into breast milk or may harm a nursing baby. You should not breastfeed while using Arimidex. You may need to take a pregnancy test before using Arimidex (Anastrozole) to make sure you are not pregnant.
Clinical efficacy of Arimidex
The pharmacokinetics of the drug has been thoroughly studied. Arimidex is rapidly and completely absorbed from the gastrointestinal tract, the maximum concentration is noted after 2 hours, the plateau is reached on the 7th day of treatment. The drug is metabolized in the liver, the half-life is 30-60 hours. Only 10% of the unchanged drug and 70% of the metabolites are excreted in the urine. There is no need to adjust the dose of the drug in hepatic or renal insufficiency.
Arimidex is well tolerated and rarely leads to a feeling of hot flashes and dryness of the vaginal mucosa, in addition, gastrointestinal disorders, drowsiness, asthenia, headaches may occur. However, cases of drug withdrawal due to side effects do not exceed 3%. The drug is not contraindicated in patients with a history of thromboembolic complications and hypertension. Arimidex is in the second line of hormone therapy for advanced breast cancer with progression after tamoxifen.
The results of two multicenter studies in the USA and Europe comparing the efficacy and toxicity of Arimidex at doses of 1 and 10 mg per day and megestrol acetate at a dose of 160 mg per day during line 2 hormone therapy (after progression on tamoxifen) in 746 patients with advanced breast cancer are presented. There were no differences in the objective effect of treatment in the three groups (12.6%, 12.5% and 12.2%, respectively). However, in the group receiving Arimidex at a dose of 1 mg per day, a significantly longer life expectancy was noted compared to megestrol acetate (26.7 months. against 22.5 months). The two-year survival rate with Arimidex therapy was 56.1% and 46.3% with megestrol acetate treatment.
When using Arimidex at a dose of 1 mg per day, there was no statistically significant difference in 2–year survival rates in patients who achieved complete and partial regression or only stabilization (85% vs. 86%). A dose of 10 mg did not improve the results of treatment with Arimidex.
A brighter result was obtained in a subgroup of patients with hepatic metastases. Clinical improvement (complete + partial regression + stabilization) with Arimidex 1 mg per day was observed in 26% of patients (n= 46) and 17% (n=41) with megestrol acetate. The duration of clinical improvement was 17.9 months and 9.9 months, respectively, in the groups.
Toxicity also differed in the group with aromatase inhibitor and megestrol: weight gain of 1.5% and 11.9%, respectively; edema of 7.3% and 13.8%; thromboembolic complications of 3.4% and 4.7%; nausea, vomiting, diarrhea of 29.4% and 21.3%; hot flashes of 12.6% and 13.8%; dryness of the vaginal mucosa of 1.9% and 0.8%.
Thus, new aromatase inhibitors, in particular Arimidex, have firmly taken the position of progestins in the second line of hormone therapy after antiestrogens in advanced breast cancer, not only due to their greater effectiveness, but also lower toxicity. Today, it is considered unjustified to prescribe progestins after ineffective treatment with antiestrogens.
The clinical efficacy of Arimidex in initial adjuvant therapy has been proven during the largest international ATAC study. The results of this study, with a median follow-up time of more than 8 years, indicate that the benefits in the effectiveness of Arimidex compared with tamoxifen remain after the end of therapy. The data obtained 100 months after the start of the study demonstrate that with the use of Arimidex, the absolute risk of all forms of relapses continues to decrease even after the end of therapy.
In a clinically important subgroup of patients with steroid hormone receptors in the tumor, the difference in the recurrence rate in the study group of patients increased from 2.7% (5 years of follow-up) to 4.3% (9 years of follow-up).
With a median follow-up time of 10 years (120 months), Arimidex compared with tamoxifen is statistically significant:
- Reduces the risk of relapse by 21% (HR 0.79 [0.70-0.89]; p=0.0002);
- Improves relapse-free survival by 14% (HR 0.86 [0.78-0.95]; p=0.003);
- Reduces the risk of distant metastases by 15% (HR 0.85 [0.73-0.98]; p=0.02);
- Reduces the risk of developing contralateral breast cancer by 38% (HR 0.62 [0.42-0.85]; p=0.003);
These results are of great importance, given the previously published data that the effect of 5-year tamoxifen therapy on the recurrence rate persists 5-9 years after the start of therapy.
To date, Arimidex is the first aromatase inhibitor with a proven pronounced "aftereffect" effect, in other words, the benefits of using the drug persist many years after the completion of active treatment.
With a median follow-up of 5 years, treatment was completed in ≥90% of patients, which allowed for a final 5-year safety and tolerability analysis. Arimidex compared with tamoxifen was characterized by significantly better tolerability in terms of the incidence of endometrial cancer, vaginal bleeding and vaginal discharge, hot flashes, cases of ischemic cerebral circulation disorders, venous vessel thromboembolism and deep vein thromboembolism.
Unlike Arimidex, in the group of patients receiving tamoxifen therapy, hysterectomies had to be performed significantly more often (this indicator was 1.3% when using anastrozole and 5.1% when prescribing tamoxifen), as well as hysterectomies due to the development of malignant neoplasms (0.3% and 0.9%, respectively).
The final analysis of the results of the ATAS study showed that discontinuation of therapy due to the development of adverse events was significantly less frequently observed when using Arimidex (11% (344/3092)) compared with tamoxifen (14.3% (442/3094); p= 0.0002). Serious adverse events caused by the use of the studied drugs were also recorded with significantly less frequency when prescribing Arimidex (4.7% (146/3092)) compared with tamoxifen (9.0% (271/3094); p<0.0001). The present analysis confirmed the safety profile of anstrozol, established at a median follow-up time of 68 months. If during the treatment period the fracture rate was higher in the anastrozole group, after the end of therapy this indicator decreased in both groups, and the frequency of bone complications in the anastrozole group was almost equal to the corresponding indicator in the tamoxifen group, the results of a sub-study in the ATAS study showed that the use of anastrozole was associated with the loss of 6-7% of bone mass during active therapy. However, there is more and more data indicating the possibility of identifying patients with low bone mineral density at the beginning of therapy and treatment of this category of patients in accordance with new clinical guidelines for the use of bisphosphonates.
To date, Arimidex has a fully characterized tolerance profile for adjuvant therapy for the entire recommended 5-year period of therapy.
It should be emphasized that the long period of observation of patients during the ATAS study, compared with other studies on aromatase inhibitors in the treatment of operable breast cancer, provides additional information about the long-term safety profile of Arimidex and demonstrates the absence of long-term side effects.Transfer to Arimidex therapy from tamoxifen therapy in adjuvant mode.
In the ITA, ARNO/ABSCG studies, the effectiveness of the therapeutic tactics of transferring postmenopausal patients with operable hormone-positive breast cancer to Arimidex was evaluated, receiving tamoxifen as adjuvant therapy for 2-3 years compared with 5-year tamoxifen intake (3,4,5).
The advantage of switching to Arimidex was demonstrated in a meta-analysis of three studies (2). Patients who were transferred to Arimidex therapy had fewer relapses of the disease (92 compared to 159) and deaths (66 compared to 90) than those who continued to receive tamoxifen. This led to a significant increase in:
- Survival without signs of disease (HR 0.59 [95% confidence interval, CI 0.48 - 0.74]; p <0.0001);
- Survival without events, i.e. without relapse and contralateral breast cancer (HR 0.55 [0.42 - 0.71]; p <0.0001);
- Survival without distant metastases (HR 0.61 [0.45 - 0.83]; p=0.002);
- Overall survival (HR 0.71 [0.52 - 0.98]; p=0.04).
The ARNO95 study confirmed the effectiveness of conversion to Arimidex in the form of a statistically significant reduction in the risk of death by 47% compared to patients receiving tamoxifen for 5 years.
The expediency of the tactics of transferring patients with operable hormone-positive breast cancer in postmenopause, receiving tamoxifen for 2-3 years after surgical treatment, to aromatase inhibitors (Arimidex ® ) was confirmed by international experts at a conference in St. Gallen, 2007.
With Arimidex, we get rid of a breast tumor
Of all the types of malignant tumors, this one is the most common among women. In addition, it ranks second (after lung cancer) among the entire population. The disease began to progress strongly in the 70s of the last century, its cause was a change in lifestyle. This was especially noted in well-developed countries – women began to give birth a little, and because of this, the breastfeeding period was reduced, which has a bad effect on the woman's body. The mammary gland consists of the same tissues, both in men and women, so this disease sometimes happens in men. However, according to statistics, out of all 100% who suffer from this disease, only 0.9% are men.
Since the disease has been very common for a long time, special attention has been focused on combating it and as a result, there are currently many ways to treat this disease. At each stage – a separate treatment. Arimidex is used to treat advanced breast cancer in postmenopausal women. The exception is patients with estrogen-negative cancer, unless they had previously had a positive clinical response to tamoxifen.
Arimidex is a highly selective nonsteroidal aromatase inhibitor, an enzyme by which androstenedione in peripheral tissues in postmenopausal women is converted into estrone and then into estradiol. Reducing the level of circulating estradiol in breast cancer patients has a therapeutic effect. In postmenopausal women, Arimidex in a daily dose of 1 mg causes a decrease in estradiol levels by 80%. Arimidex does not have progestogenic, androgenic and estrogenic activity. Arimidex in daily doses up to 10 mg has no effect on the secretion of cortisol and aldosterone, therefore, when using the drug Arimidex, replacement administration of corticosteroids is not required.
In the future, you need to consult a personal doctor. Given the peculiarity of the female body, the task of women is especially to monitor their body. If all women listened to this, then in most cases everything would go without terrible consequences.
If you belong to women who take care of their health, then if necessary, Arimidex will come to your aid. If your disease is not detected at an early stage, then Arimidex will also not be superfluous.