Liquid Arimidex, also known as anastrozole is not a steroid, it belongs to a class of drugs known as aromatase inhibitors but many buy liquid Arimidex because of its use with steroids can often be very important. Many steroids cause an increase in estrogen in the body by a conversion process brought on by the aromatase enzyme.
Even testosterone, the primary male hormone will convert to the primary female hormone once the aromatase process takes place. When this occurs many of the common side effects associated largely with anabolic androgenic steroids are shown in a pronounced manner. Side effects like, Gynecomastia (male breast enlargement) and excess water retention/bloat are often the two most prominent effects.
Why liquid Arimidex inhibits the aromatase process from occurring should be reasonably simple to understand why anyone would buy Arimidex; when we use anabolic steroids we simply buy Arimidex to keep estrogen at bay and to avoid the commonly associated side effects of increased levels. It should be noted, when you buy proper liquid Arimidex and responsible use it is very important as reducing your estrogen too low can have negative consequences, especially for the immune system; some estrogen is imperative to a healthy and well-functioning body.
The randomized, multicentre, double-blind study ATAC (Arimidex, Tamoxifen Alone or in Combination) was started in 1996 to answer the following questions:
- Is the aromatase inhibitor anastrozole (Arimidex ® ) as effective as the previous “gold standard” tamoxifen in adjuvant breast cancer treatment of postmenopausal women?
- Does anastrozole treatment have safety and side effects?
- Can a combination of anastrozole and tamoxifen offer more safety or effectiveness than tamoxifen monotherapy?
Tamoxifen: first choice so far
The estrogen receptor antagonist tamoxifen has been a standard therapeutic agent in the treatment of hormone-sensitive breast cancer for 30 years. It is approved for adjuvant therapy after primary treatment and for palliative treatment of metastatic breast cancer. Although the substance is tolerated relatively well, endometrial carcinomas and thromboembolism occur in addition to various gynecological complications when taken for a long time.
For about 10 years, reversible and irreversible aromatase inhibitors (see box) have been used in women with postmenopause for adjuvant therapy of breast cancer. The results of the ATAC study show a significant superiority over tamoxifen for the aromatase inhibitor anastrozole, which was introduced into therapy in 1995.
Box text: Aromatase inhibitor
Aromatase is an enzyme complex that catalyzes the conversion of androgens into estrogens in the ovaries, muscles, adipose tissue and breast cancer cells. This is done by oxidative removal of the C-19 methyl group and simultaneous aromatization of ring A. A distinction is made between reversible aromatase inhibitors [aminogluthetimide (Orimeten®), anastrozole (Arimidex®), letrozole (Femara®)] and irreversible inhibitors [exemestane (Aromasin ®), Formestane (Lentaron®), Testolacton (Fludestrin®)].
study design
The study involved 9366 postmenopausal women whose primary therapy (surgery, radiation or chemotherapy) had been completed and who appeared suitable for adjuvant therapy. 84% of all patients were hormone receptor-positive. 3125 women received anastrozole (1 mg daily), 3116 tamoxifen (20 mg daily) and 3125 patients a combination of both. The combination therapy was hoped for advantages through additive or synergistic effects of the two active ingredients. The recently published data refer to the observation period from July 1996 to March 2000. The mean observation period was 33.3 months.
Significantly higher effectiveness of anastrozole
Treatment with anastrozole was found to be significantly more effective than that with tamoxifen or combination therapy during the observation period. In the anastrozole group, 317 of 3125 women (10.1%) developed metastases or relapses or died. These events occurred in 12.2% (379 of 3116 women) in the tamoxifen group and in 12.3% (383 of 3125 women) in the combination group.
In other words, disease-free survival was significantly longer in women treated with anastrozole than those treated with tamoxifen or combination therapy. However, the combination therapy was not significantly different from the tamoxifen treatment. The superiority of anastrozole was shown even more clearly in the subgroup of hormone-receptor-positive patients.
Compatibility and security
All three treatment regimens were well tolerated by most patients. There were significantly fewer treatment discontinuations in the anastrozole group than in the tamoxifen group. This could also be due to the fact that anastrozole therapy had significantly fewer hot flashes, vaginal bleeding, ischemic cerebrovascular events, venous thromboembolism, and endometrial cancer compared to tamoxifen treatment.
However, skeletal muscle diseases and fractures were significantly less common with tamoxifen treatment. This is probably due to the partially agonistic effects of the estrogen receptor antagonist. Despite the encouraging results of the study, a longer follow-up period is required to make a final benefit-risk assessment. For example, the safety of anastrozole over a therapy period of five years is currently unclear.
New registrations this year?
Based on the new study results, AstraZeneca is aiming for approval of the aromatase inhibitor in women in early breast cancer stages this year. The American approval agency FDA is currently examining the application for an extension of approval for adjuvant treatment of breast cancer. So far, anastrozole has been approved as first-line therapy for postmenopausal women with advanced or metastatic hormone-sensitive breast cancer and as second-line therapy after tamoxifen treatment.
