1Division of Gastroenterology and Hepatology, Department of Medicine III, Medical University of Vienna, Vienna, Austria.
2Rare Liver Disease (RALID) Center of the European Reference Network for Rare Hepatological Diseases (ERN RARE-LIVER), Medical University Vienna, Vienna, Austria.
3Department of Medicine 4, Klinik Ottakring, Vienna, Austria.
4Medical University of Innsbruck, Innsbruck, Austria.
5Center of Clinical Virology, Medical University of Vienna, Vienna, Austria.
6Kepler Universitätsklinikum, Linz, Austria.
7SALK und Paracelsus Medical University, Salzburg, Austria.
8Department of Medicine, Landeskrankenhaus Hall, Austria.
Background: Bulevirtide (BLV) blocks the uptake of the hepatitis D virus (HDV) into hepatocytes via the sodium/bile acid cotransporter NTCP. BLV was conditionally approved by the EMA but real-life data on BLV efficacy are limited.
Methods: Patients were treated with BLV monotherapy. Patients who did not achieve further decreases in HDV-RNA after 24 weeks were offered PEG-IFN as an add-on therapy in a response-guided manner.
Results: Twenty-three patients (m: 10, f: 13; mean age: 47.9 years, cirrhosis: 16; median ALT: 71 IU/ml; median HDV-RNA: 2.1 × 105 copies/ml) started BLV monotherapy (2 mg/day: 22; 10 mg/day: 1). Twenty-two completed ≥24 weeks of treatment (24-137 weeks): Ten (45%) were classified as BLV responders at week 24. BLV was stopped in two patients with >6 months HDV-RNA undetectability, but both became HDV-RNA positive again. One patient was transplanted at week 25. One patient terminated treatment because of side effects at week 60. Ten patients are still on BLV monotherapy. Adding PEG-IFN in eight patients induced an HDV-RNA decrease in all (1.29 ± 0.19 [SD] log within 12 weeks). HDV-RNA decreased by >2log or became undetectable in 45%(10/22), 55%(11/20), 65% (13/20) and 69% (9/13); and ALT levels normalised in 64% (14/22), 85% (17/20), 90% (18/20) and in 92% (12/13) patients at weeks 24, 36, 48 and 60, respectively. Portal pressure decreased in 40% (2/5) of patients undergoing repeated measurement under BLV therapy.
Conclusion: Long-term BLV monotherapy is safe and effectively decreases HDV-RNA and ALT-even in patients with cirrhosis. The optimal duration of BLV treatment alone or in combination with PEG-IFN remains to be established. An algorithm for a response-guided BLV treatment approach is proposed.