Centchroman, a selective estrogen receptor modulator, as a contraceptive and for the management of hormone‐related clinical disorders

DL ‐Centchroman (67/20; INN: Ormeloxifene)1,2 synthesized at the Central Drug Research Institute, Lucknow, is a nonsteroidal once‐a‐week oral contraceptive. It was introduced in Delhi in July, 1991,3–5 marketed in India in 1992 as Saheli and Choice‐7 (Hindustan Latex Ltd., Thiruvananthapuram) and Centron (Torrent Pharmaceuticals India Ltd., Ahmedabad),4,6 and included in the National Family Welfare Programme in 1995.5 According to post‐marketing surveillance,5 ∼100,000 women were using this pill and ∼1100,000 menstrual cycles were covered until 1996. It is a unique need‐oriented contraceptive being effective when taken immediately after coitus or routinely as a weekly pill2,5–19 and has the advantage of less frequent administration. Its contraceptive action is quickly reversible. It has long terminal serum halflife of 168 hr in women and exhibits duration of anti‐implantation/estrogen antagonistic action of 120 hr, despite a short (24.1 hr) serum halflife, in the rat. In lactating women, it is excreted in milk in quantities considered unlikely to cause any deleterious effect on suckling babies.20–21 In phase II and III multicentric trials as a contraceptive, children born of method‐and‐user failure pregnancies showed normal milestones, without any congenital anomaly. Reports of its promising action in the management of certain hormone‐related clinical disorders are available. It has an excellent therapeutic index and is considered safe for chronic administration. © 2001 John Wiley & Sons, Inc. Med Res Rev, 21, No. 4, 302–347, 2001