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A builder with back pain
Published in Tim French, Terry Wardle, The Problem-Based Learning Workbook, 2022
Hormone treatment depends on the fact that, being a sex gland, the prostate is sensitive to circulating levels of testosterone. Removing testosterone from the circulation causes the regression of prostate cancer cells. Such manipulation started with either bilateral orchidectomy or stilboestrol. Since then, many further forms of hormone manipulation have been developed. The essence of treatment is to maximise the benefits, which have altered little since the introduction of the initial methods of hormone manipulation, while minimising side-effects. Such treatment is often given in primary care with the advice of a urologist. An important point to remember is that the LHRH analogues (Zoladex) cause an initial increase in testosterone levels, which could briefly exacerbate symptoms. Therefore, in this case cyproterone acetate (Casodex) should be given for the first 2–3 weeks in addition to any such treatment.
Urological Anti-cancer Agents
Published in Karl H. Pang, Nadir I. Osman, James W.F. Catto, Christopher R. Chapple, Basic Urological Sciences, 2021
Bernadett Szabados, Thomas Powles
Cyproterone acetateDual mechanism of action:Inhibition of prostate cells AR.Negative feedback effect on the hypothalamus and pituitary gland.Side effects: similar to LHRH antagonists:Depressed mood, dyspnoea, fatigue, gynaecomastia, hepatic disorders, hot flush, hyperhidrosis, nipple pain, restlessness, weight change
Endocrine Therapies
Published in David E. Thurston, Ilona Pysz, Chemistry and Pharmacology of Anticancer Drugs, 2021
The mechanism of action of CPA at the clinical level is complex. At the AR, it directly blocks endogenous androgens such as testosterone and dihydrotestosterone (DHT) from binding to and activating the receptor, thus inhibiting an androgenic effect, and also acts centrally by binding to ARs expressed in the hypothalamus and pituitary. This suppresses the corticotropic axis and reduces plasma testosterone levels due to its progestin-like activity as well as its own low agonist activity, which is approximately 1/10 that of testosterone. Therefore, cyproterone blocks the negative feedback of androgens at the hypothalamic–pituitary level (Figure 8.24) leading to increased Luteinizing Hormone serum levels which cause an increase in serum testosterone and ultimately diminishes the ability of cyproterone to compete for AR binding and to block androgenic stimulation. However, it is not a pure AR antagonist but a very weak partial agonist, although clinically it behaves only as an anti-androgen, as it displaces the more efficacious endogenous androgens such as testosterone and DHT from the receptor with a net effect of lowering physiological androgenic activity.
Androgen receptor modulators: a review of recent patents and reports (2012-2018)
Published in Expert Opinion on Therapeutic Patents, 2019
Shinya Fujii, Hiroyuki Kagechika
Since AR activation is closely related to aggravation of prostate cancer, AR antagonists are used clinically for the treatment of prostate cancer [18–21]. Cyproterone acetate (7) is a steroidal AR antagonist used in the treatment of androgen-dependent disorders including prostate cancer (Figure 3) [22,23]. Oxendolone (8) is used in the treatment of enlarged prostate in Japan [24]. However, steroidal antagonists exhibit side effects due to cross-activity with other steroid hormone receptors, and therefore various nonsteroidal AR antagonists (nonsteroidal antiandrogens, NSAAs) have been developed. Flutamide (9) is one of the first-generation nonsteroidal AR antagonists; it was discovered in 1967 and has been in clinical use since the 1980s [25,26]. Flutamide (9) has also been a lead compound for the development of various novel nonsteroidal AR antagonists. Two other first-generation NSAAs, the hydantoin derivative nilutamide (10) [27,28] and the sulfone derivative bicalutamide (11) [29,30], have been in clinical use since the 1990s. Bicalutamide (11) is the most potent of the three, having the highest receptor affinity and a superior ADMET profile [31], and is, therefore, the most widely used first-generation NSAA for prostate cancer. Topilutamide (12) is also a first-generation NSAA used for the treatment of pattern hair loss in the Czech Republic and Slovakia [32].
Spherical agglomeration to improve dissolution and micromeritic properties of an anticancer drug, Bicalutamide
Published in Drug Development and Industrial Pharmacy, 2019
Hitesh Dalvadi, Komal Parmar, Suryabali Yadav
Bicalutamide (BCT) is a nonsteroidal antiandrogen that is used widely in the treatment therapy of prostate cancer. It stops testosterone from reaching the cancer cells. It is not reported to cause any side effects associated with steroidal antiandrogens like cyproterone acetate and shows the absence of any known progestational activities. Elimination half-life of BCT is about one week and thus is compatible with once-daily dosing. BCT is a lipophilic drug with log P octanol/water value of 2.92, where P is the partition coefficient and depicts a very low solubility in water (<5 mg/L). Various researchers have investigated different approaches to improve the dissolution properties of BCT [16–18]. Heretofore, there is no work reported whereby micromeritic and dissolution properties of BCT have been improved by spherical crystal agglomeration technique. Hence, the authors endeavor to study the influence of processing conditions and formulation parameters on the formation of BCT agglomerates and its properties viz. micromeritic and dissolution. Principal component analysis and Box-Behnken experimental design were utilized to optimize the prepared agglomerates of BCT.
An evaluation of the available pharmacotherapy for the treatment of hirsutism
Published in Expert Opinion on Pharmacotherapy, 2023
Leila Asfour, Ahmed Kazmi, Rodney Sinclair
In countries where Cyproterone Acetate is available (mostly Europeans), it is used at higher doses (25 to 50 mg/d in association with an estrogen). Under such dosages, the efficacy is much more important than with OCP alone, although no sufficiently powered randomized study has been performed [37]. The major drawback of theses doses is the risk of basal skull meningioma that is 5-fold the natural risk, when using more than 25 mg/d and/or more than 5 treatment years [38]. It is therefore recommended to perform a cranial MRI before initiating such treatment and to control after one year and then every two years [39].