Over the course of 20 years Pfizer invested more than $1 billion into the discovery, development and commercialization of Xeljanz. This extensive effort included screening hundreds of thousands of compounds in our proprietary file to identify a lead molecule, preparing more than 1,000 variations of our original lead molecule in order to come up with one investigational compound, and over the course of a decade, conducting one of the largest clinical trial programs in RA at the time, encompassing more than 5,000 patients in over 550 locations in more than 40 countries in order to evaluate the safety and efficacy of the Xeljanz compound.

It was the culmination of this work undertaken by Pfizer that led to the drug now known as Xeljanz, the first new oral disease-modifying therapy in more than 10 years for adults with moderately to severely active rheumatoid arthritis.

The prices of brand name medicines are based on the value they will provide patients and healthcare providers, the scientific innovation they represent and the investment by Pfizer in comprehensive, multi-study, global clinical development programs.

Background Timeline:

1. Pfizer believes it first became aware of the JAK pathways at a scientific conference in 1993 in which John O'Shea, MD, presented experimental findings about the JAK3 enzyme. Dr. O'Shea's findings were also published in 1994. This research was in the public domain, and thus widely accessible.
2. At that time, Pfizer was exploring potential immunosuppressant agents in the field of transplantation. Thus, between 1993 and 1996, Pfizer began exploratory biology that ultimately led to the discovery of the Xeljanz^® molecule (tofacitinib).
3. On a parallel path, Pfizer entered a CRADA with NIH to better understand the interaction between JAK3 and cytokine receptors, specifically one receptor (IL-2). Although this line of exploration occurred simultaneously with Pfizer's efforts to discover Xeljanz, it concerned a different theory for treating inflammation. Pfizer provided the majority of the funding for the research.
   • The NIH work was led by Dr. O'Shea, an outstanding scientist who led a team that cloned JAK3.
   • The research that he and his team performed under the CRADA advanced scientific knowledge regarding the role of cytokine signaling in inflammation pathways. However, it did not lead to discovery of the Pfizer compound which resulted in Xeljanz.
4. To our knowledge, the CRADA did not yield any compounds or patentable intellectual property. Under the terms of the CRADA, the NIH was entitled to — and did — make publicly available the results of the research supported by Pfizer, including ten publications. In this way, the CRADA benefited the entire research community and the public at large.
5. Beginning in 1996, Pfizer scientists screened thousands of compounds in a proprietary compound file against the JAK3 enzyme. This led to identification of Pfizer's lead compound. Between 1997 and 2000, Pfizer made synthetic analogs of this lead molecule.
   • In the late 1990s/early 2000s, Pfizer obtained a non-exclusive license from the NIH for certain patents relating to the JAK-3 protein to be used for research purposes. John O'Shea was one of the inventors. Pfizer paid the NIH for the license, and has been one of approximately ten companies to do so. Pfizer independently developed a screening assay to identify a lead compound and subsequently optimized that lead through continued screening efforts. This work drew on a broad knowledge set and is one of a multitude of steps that make the invention of a molecule possible.
6. In all, Pfizer prepared more than 1,000 variations (or synthetic analogs) of the original lead, eventually generating an investigational compound, which is known as tofacitinib. Pfizer filed for a patent covering tofacitinib in December 2000, and it was issued in September 2003.
7. Pfizer then spent more than a decade conducting one of the largest clinical trial programs in RA at that time, to evaluate the safety and efficacy of Xeljanz. In doing so, Pfizer took on the great risk and expense associated with development of this compound.
8. Today, as a result of Pfizer's efforts, Xeljanz is approved in the U.S., bringing medical benefit and value to patients and our health care system.