Better known as FSGS, focal segmental glomerulosclerosis is a rare kidney disorder without an approved pharmacological treatment option that often leads to end-stage renal disease.1

FSGS is defined by progressive scarring of the kidney and characterized by proteinuria, where protein is found in the urine due to a breakdown of the normal filtration mechanism in the kidney.2,3 Reducing proteinuria levels is widely regarded to be beneficial in the treatment of FSGS, and may be associated with a decreased risk of progression to end-stage renal disease. Other common symptoms of the disorder include swelling in parts of the body known as edema, as well as low blood albumin levels, abnormal lipid profiles, and hypertension.2

FSGS is estimated to affect up to 40,000 patients in the U.S. with a similar prevalence in Europe.4 Conservative estimates suggest that more than 5,400 patients in the U.S. are diagnosed with FSGS every year and that new cases are on the rise.5 The disorder occurs more frequently in adults than in children and is most prevalent in adults 45 years or older.6

Most often, the cause of the disorder is unknown, or idiopathic. Less frequently, FSGS is associated with comorbidities, or other conditions, such as kidney defects from birth (dysplasia), urine backing up into kidneys (kidney reflux), obesity, sleep apnea, viruses and blood disorders, such as HIV and sickle cell anemia, and autoimmune disorders, such as lupus.2

FSGS is diagnosed through a renal biopsy, but since only some sections of the kidney's normal filtration mechanism (or glomeruli) are affected, the biopsy can sometimes be inconclusive.5

FSGS patients are currently managed with steroids, calcineurin inhibitors, angiotensin receptor blockers and angiotensin converting enzyme inhibitors.5 We are exploring the potential of an investigational therapy for FSGS that could be the first FDA-approved pharmacologic treatment for people living with the disorder. Learn more about this investigational therapy.

The following organizations may be a resource for information and support for people with FSGS and those around them:

NephCure Kidney International

NephCure Kidney International is an organization committed exclusively to support research seeking the cause of the potentially debilitating kidney disease Focal Segmental Glomerulosclerosis (FSGS) and the diseases that cause Nephrotic Syndrome, improve treatment, and find a cure.

Kidney & Urology Foundation of America

The Kidney & Urology Foundation of America (KUFA) is a national, 501 c(3) not-for-profit organization dedicated to helping people with kidney and urologic diseases and individuals waiting for organ and tissue transplants. The Kidney & Urology Foundation focuses on care and support of the patient, the concerns of those at risk, education for the community and medical professionals, methods of prevention, and improved treatment options.

Global Genes

Global Genes is a non-profit patient advocacy organization working to eliminate the challenges of rare disease by building awareness, educating the global community, and providing critical connections and resources that equip advocates to become activists for their disease.  Global Genes promotes the needs of the rare disease community under a unifying symbol of hope – the Blue Denim Genes Ribbon™. Numerous tools, resources and educational events can be found on the Global Genes website www.globalgenes.org.

National Organization for Rare Disorders

The National Organization for Rare Disorders (NORD) is a unique federation of voluntary health organizations dedicated to helping people with rare "orphan" diseases and assisting the organizations that serve them. NORD is committed to the identification, treatment and cure of rare disorders through programs of education, advocacy, research and service. In the US, NORD is also the official sponsor of Rare Disease Day, an annual global observance that raises awareness of rare diseases and elevates them into the public consciousness as an important health issue that cannot be ignored.


EURORDIS is a non-governmental patient-driven alliance of more than 700 rare disease patient organisations in more than 60 countries. EURORDIS strives to build a strong pan-European community of patient organisations and people living with a rare disease, to be their voice at the European level, and - directly or indirectly - to fight against the impact of rare diseases on their lives. EURORDIS leads global efforts for Rare Disease Day and the online social platform for people living with or affected by a rare diseases RareConnect. EURORDIS represents the voice of an estimated 30 million people living with a rare disease in Europe. Follow @eurordis or see the EURORDIS Facebook page. For more information visit: www.eurordis.org.


  1. Middleton, et al. Nephrology Rounds 2007; 5(4).
  2. D'Agati, et al. N Engl J Med 2011;365:2398-411.
  3. The National Kidney Foundation. Focal Glomerulosclerosis. Available at: https://www.kidney.org/atoz/content/focal. Last accessed: July 28, 2016.
  4. Data on file. San Diego, CA: Retrophin, Inc.; July 2016.
  5. NephCure Kidney International. FSGS Facts. Available at: http://nephcure.org/livingwithkidneydisease/understanding-glomerular-disease/understanding-fsgs/fsgs-facts/. Last accessed: July 28, 2016.
  6. NephCure Kidney International. FSGS Overview. Available at: http://nephcure.org/wp-content/uploads/2014/08/Focal-Semental-Glomerulosclerosis-Fact-Sheet.pdf. Last accessed: July 28, 2016.