SBIR-STTR Award

This program seeks to develop a one year biodegradable estrogen/progestin implant for postmenopausal hormone replacement therapy. The program will utilize a proven hormone combination, estradiol and levonorgestrel. It has been shown that side effects of estrogen therapy can be lowered by administering a progestin with the estrogen. Both hormones will be incorporated into an innovative implant design already under development by BIOTEK to deliver pure levonorgestrel as a maintenance contraceptive. The new implant is thermoformed from very high molecular weight poly-L-lactide, using a method which minimizes degradation during manufacture. The implant has a hormone-loaded outer shell for efficient drug delivery and a pure polymer core for mechanical strength. The implant will biodegrade if left in place for more than one year, but it can be surgically removed for medical reasons at earlier times. With no need to keep track of daily dosing, and little reason to anticipate an unpleasant removal episode, both women and doctors should welcome such implants as a convenient new form of estrogen replacement therapy combining almost effortless compliance with stable hormone levels. PROPOSED COMMERCIAL APPLICATIONS: The proposed work involves incorporating a drug into the outer portion of a strong, easily administered implant which biodegrades when left in the body for more than a year. The same technique could be useful for delivery of other chronically administered hormones and maintenance medications

This program targets a one-year biodegradable estrogen/progestin implant for postmenopausal hormone replacement therapy. Estradiol plus levonorgestrel will be incorporated into an innovative implant design already being developed by BIOTEK for delivery of pure levonorgestrel as a maintenance contraceptive. The implant consists of a drug-free, biodegradable polymer core surrounded by a drug-containing shell, which provides efficient drug delivery. Such implants will biodegrade if left in place for more than a year, yet they can be surgically removed before the end of a year if necessary. With no need to keep track of daily pills or weekly patches, and with little reason to fear an unpleasant removal episode, such implants should provide a welcome new form of sustained hormone replacement therapy. Phase I demonstrated the feasibility of delivering estradiol and levonorgestrel at acceptable rates from the same implants. Phase II will now modify the core polymer to accelerate degradation, improve production methods, characterize promising designs in vitro, and confirm performance in rabbits. PROPOSED COMMERCIAL APPLICATION: The proposed work should lead to the development of a new kind of long lasting, highly effective, biodegradable drug delivery implant. Once fully impemented, implants of similar design should be useful for many other kinds of drug maintenance therapy.

Thesaurus Terms:
biodegradable product, biomaterial development /preparation, drug delivery system, estrogen, implant, levonorgestrel, progestin drug administration rate /duration, drug screening /evaluation, estradiol, hormone therapy, microcapsule, pharmacokinetics, placebo histology, laboratory rabbit