BIODEGRADABLE NORETHINDRONE (NET-CHOLESTEROL) CONTRACEPTIVE IMPLANTS - PHASE II-A - A CLINICAL-STUDY IN WOMEN

Safety, contraceptive efficacy and biodegradability of subdermal noret hindrone (NET)-cholesterol implants (Anuelle(R)) were investigated in 19 healthy, sexually active women. Mean serum NET levels in women with four and five pellets, containing 174 mg and 266.5 mg NET, showed a ' 'burst-effect'' of 3.17 and 3.71 ng/ml, respectively, within 24 h post implantation. Subsequently for the four- and five-pellet groups, resp ectively, the levels declined from 0.75 to 0.40 ng/ml and 1.05 to 0.61 ng/ml during the months 12-25, from 0.40 to 0.11 ng/ml and 0.61 to 0. 25 ng/ml up to month 36. The serum NET levels were undetectable at 36 months and beyond, indicating complete biodegradability of MET pellets . Serum E(2) levels remained within normal limits (>50 pg/ml), whereas serum P indicated anovulatory cycles in 78% of the four-pellet group and 99% of the five-pellet group. FSH and ill levels were subnormal an d acyclic. Plasma lipids showed reduced total and LDL cholesterol and triglycerides. HDL cholesterol remained unchanged. Drag-related advers e effects were essentially Limited to irregular bleeding. There were n o pregnancies in either group. (C) 1997 Elsevier Science Inc.