Mevalonate kinase deficiency (HyperIgD syndrome, HIDS) is an inborn error of immunity caused by a block in the mevalonate pathway. The subsequent lack of isoprenoids with antiinflammatory properties might contribute to the autoinflammatory nature of the disease.

A pilot study aims to verify the safety and efficacy of the dietary supplement Geranylgeraniol, aiming at a mitigation of isoprenoids deficiency caused by the above-mentioned block in the MVK pathway.

Mevalonate kinase (MVK) deficiency, a rare autosomal recessive disease, significantly impacts metabolism and immunity, leading to mevalonic aciduria in severe cases and hyper-IgD syndrome (HIDS) in partial deficiency. These conditions arise due to disruptions in the mevalonate pathway, which is an essential metabolic pathway responsible for the synthesis of non-sterol isoprenoids and other molecules. The resulting metabolic blockade triggers autoinflammatory responses, primarily due to deficient isoprenoid intermediates such as geranylgeranyl pyrophosphate (GGPP).

This study evaluates the safety and efficacy of dietary geranylgeraniol (GG) supplementation in patients with genetically confirmed mevalonate kinase deficiency.

The pilot study consists of a month of a pre-supplementation period to monitor the level of inflammation and clinical status in patients with MVK deficiency(HIDS).

This period is followed by 3 months of supplementation of 150mg of GeranylGraniol (GG Pure (Extendlife Natural Products) containing GG gold®30 Annatto Extract, 500 mg capsule (30% geranylgeraniol, 150 mg per capsule).

Inclusion Criteria:

• Patients older than 12 years with genetically confirmed MVK deficiency
• Overall good clinical status apart from the clinical presentation of the MVK deficiency
• Normal liver tests
• Compliance with the study protocol

Exclusion Criteria:

• Children below 12 years

anonymized patient data consisting of clinical and laboratory sets of follow-up parameters are shared with participating researchers