Long Term Effects of Leptin on Hepatic Fibrosis in Generalized Lipodystrophy

Abstract Lipodystrophy syndromes are caused by deficiency of adipose tissue leading to severe insulin resistance, hypertriglyceridemia, and non-alcoholic fatty liver disease (NAFLD), which may progress to cirrhosis. Advanced fibrosis/cirrhosis was previously thought to be irreversible; however, eradication of hepatitis C or long-term viral suppression of hepatitis B can reverse cirrhosis. Metreleptin treatment in patients with lipodystrophy improves liver transaminases and NAFLD activity score (NAS) after a mean of 2 years, but the latter improvements were due to lower inflammation and steatosis, with no change in fibrosis. The long-term effects of metreleptin in subjects with advanced fibrosis are unknown. We analyzed 24 subjects with advanced fibrosis (NAS stage 3 or 4) prior to metreleptin. Seven had liver biopsies both before and after ≥ 3 years of metreleptin with mean treatment duration 7.8±2.9 years. Five of six subjects with stage 3 fibrosis at baseline had improved fibrosis scores after metreleptin, and 0 of 1 with stage 4 fibrosis improved. 17 patients (8 with stage 3, 9 stage 4) did not have follow up biopsies after ≥3 years. Of these 17, 4 (all stage 4) died from end stage liver disease, and 1 (stage 3) from other causes. There was no clinical indication for repeat biopsy in 6 patients (2 stage 3, 4 stage 4). 6 were lost to follow up. Of the 24 patients with advanced fibrosis, 13 had congenital generalized lipodystrophy (CGL), 7 had acquired generalized lipodystrophy (AGL), 3 had familial partial lipodystrophy (FPL) and 1 had acquired partial lipodystrophy (APL). Of the 5 subjects with improvement in their fibrosis score, 2 had AGL, 2 had CGL, and one had a novel FPL mutation (1). Of the two patients that did not improve, one had FPL and one had CGL. In conclusion, subjects with stage 3 fibrosis due to lipodystrophy may have regression of fibrosis after long-term metreleptin treatment. This improvement may be secondary to near-elimination of the inciting factors (excess nutrient intake leading to ectopic lipid storage in the liver), analogous to clearance of Hepatitis C infection. However, additional data is needed to determine if metreleptin can reverse fibrosis in subjects with stage 4 fibrosis.