Contraceptive steroids release, poly

Controlled release fiber systems based on aliphatic polyesters were investigated by Dunn and Lewis (51-54). The feasibility of hollow fibers spun from poly (L-lactide) and containing the contraceptive steroid levonorgestrel has been demonstrated (55). 

Heller, J., Penhale, D. W. H., Fritzinger, B. K., Rose, J. E., and Helwing, R. F., Controlled release of contraceptive steroids from biodegradable poly(ortho esters), Contracept. Deliv. Syst., 4, 43-53, 1983. 

J. E., Synthesis and release of contraceptive steroids from bio-erodible poly(ortho esters), in Polymers in Medicine (E. Chielini and P. Giusti, eds.). Plenum Publishing, New York, 1983, pp. 169-178. 

Although the Alza poly(ortho ester) system has never been structurally identified other than by its tradename Chronomer, and later Alzamer, several publications provide a general description of the use of the polymer for the release of naltrexone (46) and contraceptive steroids (47. 48, 49). 

Release of levonorgestrei. Considerable work has been expended on the development of a poly (ortho ester) implant that can deliver a contraceptive steroid from a subcutaneous or intramuscular implant for about one year at close to zero order kinetics and where drug depletion and polymer erosion occur at about the same time. Initial funding for the development for the poly (ortho ester) II system was provided by the Contraceptive Development Branch of NIH with the objective of developing such a contraceptive system. 

SYNTHESIS AND RELEASE OF CONTRACEPTIVE STEROIDS FROM BIOERODIBLE POLY(ORTHO ESTER) S... 

J. Heller, D.W.H. Penhale, B. K. Fritzinger, J. E. Rose, and R. F. Helwing, Controlled Release of Contraceptive Steroids from Biodegradable Poly(Ortho Esters), Contracept. Deliv. Systems, 4 000 (1983). 

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