DESCRIPTION OF BUSINESS

Organization and Description of Business

Retrophin, Inc. (“we”, “our”, “us”, “Retrophin” and the “Company”) refers to Retrophin, Inc., a Delaware corporation, as well as our direct and indirect subsidiaries. Retrophin is a fully integrated biopharmaceutical company headquartered in San Diego, California focused on the development, acquisition and commercialization of therapies for the treatment of serious or rare diseases. We regularly evaluate and, where appropriate, act on opportunities to expand our product pipeline through licenses and acquisitions of products in areas that will serve patients with serious or rare diseases and that we believe offer attractive growth characteristics.

We are currently developing the following pipeline products:

Sparsentan is an investigational therapeutic agent which acts as both a potent ARB, as well as a selective ERA, with in vitro selectivity toward endothelin receptor type A. The Company has secured a license to sparsentan from Ligand Pharmaceuticals, Inc. and Bristol-Myers Squibb Company (who referred to it as DARA). The Company is developing sparsentan as a treatment for FSGS, which is a leading cause of end-stage renal disease and NS. Sparsentan was granted orphan drug designation in the United States and the European Union in January 2015 and November 2015, respectively. In the third quarter of 2016, the Company announced positive top-line data from the Phase 2 DUET study of sparsentan for the treatment of FSGS. In early 2017, we had an End of Phase 2 meeting with the FDA regarding the regulatory pathway for sparsentan as a treatment for FSGS. Following the meeting and our receipt of confirmatory meeting minutes, we announced our plans to initiate a single Phase 3 clinical trial to serve as the basis of a New Drug Application ("NDA") filing for sparsentan for the treatment of FSGS.

Fosmetpantotenate, also known as RE-024, a novel small molecule, is being developed as a potential treatment for pantothenate kinase-associated neurodegeneration (“PKAN”). PKAN is a genetic neurodegenerative disorder that is typically diagnosed in the first decade of life. Consequences of PKAN include parkinsonism, dystonia, and other severe systemic manifestations. Fosmetpantotenate (RE-024) is a phosphopantothenate replacement therapy that aims to restore levels of this key substrate in PKAN patients. Certain international health regulators have approved the initiation of dosing fosmetpantotenate (RE-024) in PKAN patients under physician-initiated studies in accordance with local regulations in their respective countries. The Company filed a U.S. IND for fosmetpantotenate (RE-024) with the FDA in the first quarter of 2015 to support the commencement of a Company-sponsored Phase 1 study, which was successfully completed during 2015. The FDA granted fosmetpantotenate (RE-024) orphan drug designation in May 2015 and fast track designation in June 2015. In February, 2016, the Company announced fosmetpantotenate (RE-024) was granted orphan drug designation by the European Commission. In November, 2016, the Company announced that it had reached an agreement with the FDA under the Special Protocol Assessment (SPA) process for a Phase 3 clinical trial evaluating fosmetpantotenate (RE-024) for PKAN. The Company expect to begin dosing patients in this Phase 3 clinical trial in the coming months. The Company continues discussions with the EMA regarding the initiation of a potential registration-enabling efficacy trial in PKAN patients.

Tetracosactide zinc (RE-034) is a synthetic hormone analog of the first 24 amino acids of the 39 amino acids contained in adrenocorticotropic hormone ("ACTH") incorporated into a novel formulation developed by us. Tetracosactide zinc (RE-034) exhibits similar physiological actions as endogenous ACTH by binding to all five melanocortin receptors (pan-MCR), resulting in its anti-inflammatory and immunomodulatory effects. The Company successfully manufactured tetracosactide zinc (RE-034) at proof-of-concept scale using a novel formulation process that allows modulation of the release of the active ingredient from the site of administration. The Company decided to focus our further efforts on this program toward an external partnership and out-licensing opportunities.

Liquid ursodeoxycholic acid ("L-UDCA") is a liquid formulation of ursodeoxycholic acid being developed for the treatment of a rare liver disease called primary biliary cholangitis ("PBC"). We obtained L-UDCA during 2016 with the intention of making L-UDCA commercially available to the subset of PBC patients who have difficulty swallowing.

We currently sell the following three products:


•	Chenodal (chenodiol tablets) is approved in the United States for the treatment of patients suffering from gallstones in whom surgery poses an unacceptable health risk due to disease or advanced age. Chenodal has been the standard of care for CTX patients for more than three decades and the Company is currently pursuing adding this indication to the label.


•	Cholbam (cholic acid capsules) is approved in the United States for the treatment of bile acid synthesis disorders due to single enzyme defects and is further indicated for adjunctive treatment of patients with peroxisomal disorders.


•	Thiola (tiopronin tablets) is approved in the United States for the prevention of cystine (kidney) stone formation in patients with severe homozygous cystinuria.