Our partnership strategy has allowed us to build a development pipeline of 25 drugs, to create a broad base of potential license fees, milestone payments, royalties, profit sharing and earn out payments and to control our drug development expenses. In this way, we remain a focused and efficient research and development organization that can continue to discover new drugs and expand ours and our partners' pipelines.
Through the efficiency of our drug discovery platform we can develop drugs to almost any gene target. We concentrate on developing antisense drugs in our core therapeutic areas of cardiovascular, metabolic, severe and rare diseases and cancer. To maximize the value of our drugs and technologies, we have a multifaceted partnering strategy. We form traditional partnering alliances that enable us to discover and conduct early development of new drugs, outlicense our drugs to partners and build a broad base of license fees, milestone payments and royalty income. We also form preferred partner transactions that provide us with a vested partner early in the development of a drug. In this way, we benefit in the short term from upfront option fees and development milestone payments while we maintain control over the early development of the drug. We benefit in the long term by having a knowledgeable and committed partner to license the drug at clinical proof-of-concept and by receiving regulatory milestone payments and royalties as our partner moves the drug to the market. We also work with a consortium of smaller companies that can exploit our drugs and technologies outside our primary areas of focus. We call these smaller companies our satellite companies. In this way, we benefit from the disease-specific expertise of our satellite company drug discovery partners, who are advancing drugs in our pipeline in areas that are outside of our core focus. Through this strategy we can expand the therapeutic range of antisense drugs into disease areas that need new and innovative treatment options.
In addition we form partnerships focused on developing and advancing certain RNA-targeting therapeutic technologies. These partnerships take advantage of our dominant intellectual property estate, and leverage our own investments in our core technologies. These collaborations typically involve a cross-license between us and our partner and allow us to participate in newly emerging approaches to RNA-targeting therapeutics and augment our active programs in these areas.
Our partnerships fall into several categories, including traditional pharmaceutical alliances and licenses, and satellite company collaborators, external project funding alliances, and technology and intellectual property sales and licensing. We discuss each of these categories in more detail below, along with the relevant partnerships.
Since 2007, our partnerships have generated an aggregate of more than $975 million in payments from upfront and licensing fees, equity purchase payments, milestone payments and research and development funding. In addition, for our current partnered programs we have the potential to earn $5.1 billion in future milestone payments. We also have the potential to share in the future commercial success of our inventions and drugs resulting from these partnerships through earn out, profit sharing, or royalty arrangements.