The goal is to develop a once-daily, oral progesterone formulation for hormone replacement therapy as indicated for postmenopausal management, oral contraception, amenorrhea, and pregnancy maintenance. The specific aims are: (1) to refine a formulation of micronized oral progesterone in a novel proprietary polymer matrix drug delivery vehicle for clinical evaluation; (2) to test dosage forms of oral progesterone for its ability to deliver steady therapeutic blood levels with once daily administration, with good stability of potency; and (3) to evaluate this formulation for further clinical development with additional refinement of dosage, if necessary. An oral form of natural progesterone would be an excellent alternative to the currently used synthetic progestins which exhibit considerable side-effects. It is further expected that an oral formulation would be more acceptable to patients than rectal, parenteral, or vaginal progesterone formulations.Awardee's statement of the potential commercial applications of the research:This project can yield a novel oral progesterone drug with once daily dosing, the first such product to be marketed in the U.S. It will address a major market need for a safe and effective alternative to synthetic progestins which have adverse side effects; and for a more acceptable oral alternative to vaginal, rectal and parenteral progesterone drugs.National Institute of Child Health and Human Development (NICHD)