Sparsentan: a dual endothelin and angiotensin II receptor antagonist approved for IgA nephropathy

INTRODUCTION: IgA nephropathy (IgAN) is the most common primary glomerulonephritis. For decades, the only medication treatments that were widely accepted were the use of renin-angiotensin aldosterone inhibitors and corticosteroids. The early 2020s have brought a flurry of new treatments to the once dark IgA treatment landscape. Sparsentan is a novel dual-endothelin angiotensin receptor antagonist that has been approved as an add-on therapy for the treatment of IgAN. AREAS COVERED: We discuss the treatment landscape and the unmet needs for treating IgA nephropathy. Multiple clinical trials showing the efficacy of sparsentan including DUET, PROTECT, SPARTACUS, and SPARTAN will be described. Additionally, we will preview the future options for IgA patients. EXPERT OPINION: Sparsentan is a major step forward in improving outcomes for patients with IgAN. This once-a-day agent, in addition to other standards of care, limits proteinuria and progression to ESKD and kidney transplantation. The ability to lower proteinuria without weakening the immune system is a substantial gain for patients. As an agent that impacts the glomeruli directly, sparsentan is able to limit damage in mechanisms that previous RASi and steroids have not. Including sparsentan in the combination treatment for IgAN must be considered for adequate kidney protection.