Treatment recommendations for glycogen storage disease type IB- associated neutropenia and neutrophil dysfunction with empagliflozin: Consensus from an international workshop.

Glycogen storage disease type Ib (GSD Ib, biallelic variants in SLC37A4) is a rare disorder of glycogen metabolism complicated by neutropenia/neutrophil dysfunction. Since 2019, the SGLT2-inhibitor empagliflozin has provided a mechanism-based treatment option for the symptoms caused by neutropenia/neutrophil dysfunction (e.g. mucosal lesions, inflammatory bowel disease). Because of the rarity of GSD Ib, the published evidence on safety and efficacy of empagliflozin is still limited and does not allow to develop evidence-based guidelines. Here, an international group of experts provides 14 best practice consensus treatment recommendations based on expert practice and review of the published evidence. We recommend to start empagliflozin in all GSD Ib individuals with clinical or laboratory signs related to neutropenia/neutrophil dysfunction with a dose of 0.3-0.4 mg/kg/d given as a single dose in the morning. Treatment can be started in an outpatient setting. The dose should be adapted to the weight and in case of inadequate clinical treatment response or side effects. We strongly recommend to pause empagliflozin immediately in case of threatening dehydration and before planned longer surgeries. Discontinuation of G-CSF therapy should be attempted in all individuals. If available, 1,5-AG should be monitored. Individuals who have previously not tolerated starches should be encouraged to make a new attempt to introduce starch in their diet after initiation of empagliflozin treatment. We advise to monitor certain safety and efficacy parameters and recommend continuous, alternatively frequent glucose measurements during the introduction of empagliflozin. We provide specific recommendations for special circumstances like pregnancy and liver transplantation.

Repurposing empagliflozin in individuals with glycogen storage disease Ib: A value-based healthcare approach and systematic benefit-risk assessment.

Off-label repurposing of empagliflozin allows pathomechanism-based treatment of neutropenia/neutrophil-dysfunction in glycogen storage disease type Ib (GSDIb). From a value-based healthcare (VBHC) perspective, we here retrospectively studied patient-reported, clinical and pharmacoeconomic outcomes in 11 GSDIb individuals before and under empagliflozin at two centers (the Netherlands [NL], Austria [AT]), including a budget impact analysis, sensitivity-analysis, and systematic benefit-risk assessment. Under empagliflozin, all GSDIb individuals reported improved quality-of-life-scores. Neutrophil dysfunction related symptoms allowed either granulocyte colony-stimulating factor cessation or tapering. Calculated cost savings per patient per year ranged between € 6482-14 190 (NL) and € 1281-41 231 (AT). The budget impact analysis estimated annual total cost savings ranging between € 75 062-225 716 (NL) and € 37 697-231 790 (AT), based on conservative assumptions. The systematic benefit-risk assessment was favorable. From a VBHC perspective, empagliflozin treatment in GSDIb improved personal and clinical outcomes while saving costs, thereby creating value at multiple pillars. We emphasize the importance to reimburse empagliflozin for GSDIb individuals, further supported by the favorable systematic benefit-risk assessment. These observations in similar directions in two countries/health care systems strongly suggest that our findings can be extrapolated to other geographical areas and health care systems.