Contraceptive development: targets, approaches and challenges.

The control of fertility constitutes a global health issue, since overpopulation and unintended pregnancy have both major personal and societal impact. Although some regions of the world are seeing neutral or negative population growth, many developing countries are seeing explosive growth of their populations and these population changes will affect the entire globe. It is estimated that in a decade, the largest cohort of young women worldwide in human history will reach adolescence thus necessitating the need for a wide range of contraceptive options that can be used by both females and males. The contraceptive revolution that occurred in the 1960s with the development of the hormonal-based oral contraceptive for women has subsequently made a significant impact on societal dynamics in several cultures, yet there has been virtually no innovation in this field since that time. This lack of innovation contrasts dramatically with the vast enhancement of our knowledge base of the basic processes of reproduction. The genomic and proteomic revolutions have provided new tools and new targets for contraceptive development, and the results of such approaches have identified gene products that play critical roles in female and male reproduction, thus expanding the array of targets for novel and innovative female- and male-based contraceptives. This normally would herald a renaissance in contraceptive development, yet the commitment of industry to this endeavor is limited to a few firms due to the economics of contraceptive development. This chapter will consider the types of targets being considered in the development of new generations of contraceptives and will also focus on the challenges that industry has in meeting these goals.