Porphyrien – was ist gesichert?

[New therapeutic option for acute hepatic porphyrias]

Givosiran is a small synthetic double-stranded siRNA (small interfering RNA) conjugated with N-acetyl-galactosamine (GalNAc) for specific hepatocyte targeting via the asialoglycoprotein receptor. A prospective randomized multicenter study (Envision) demonstrated the clinical efficacy of monthly subcutaneous injection of Givosiran for the prevention of attacks of acute hepatic porphyria (AHP). This leads to highly selective transcriptional inhibition of the key hepatic enzyme, aminolaevulinate synthase 1, that is overexpressed in AHP. The success of the Envision study has led to the approval of Givosiran in the US and Europe for the treatment of severe AHP. This innovative guided siRNA therapy has opened up the possibility to selectively inhibit the expression of any hepatocyte gene whose overexpression that causes pathology, which can be considered a milestone development in hepatology. However, currently this treatment with givosiran is very costly. Moreover, since some patients experience worsening of kidney function and elevated aminotransferases, monthly monitoring of these parameters is necessary in the first half year of treatment.

[Abdominal pain and seizure in a 26-year-old student from England]

A 26-year-old female presented to the emergency department due to abdominal pain in spite of painkillers. After extensive clinical diagnostics, no specific cause could be found. The further course was aggravated by a seizure due to hyponatremia. The combination of abdominal and neurological symptoms as well as darkening of the urine led to the diagnosis of porphyria. Drugs that were known to be triggers were avoided and treatment with heme arginate and glucose was started. In addition, treatment of the delirium and infection led to a complete remission of symptoms.