Table 2.

Emerging novel therapies for HDV

Drug	Type	Actions	Delivery	Phase of development	Comments
Peg-IFN-lambda	Type III Interferon	Immune modulation	Subcutaneous injection	Phase II	Virological response at 24 weeks post treatment = 36% Better tolerated than Peg-IFN-alpha
Lonafarnib	Farnesyl transferase inhibitor	Inhibits HDV genome replication and induces innate immunity	Oral	Phase III	HDV RNA levels decline with monotherapy Combining with ritonavir allowed lower doses to be used and had fewer GI side effects Combining with Peg-IFN-lambda resulted in 50% of patients achieving undetectable HDV RNA levels at 24 weeks' post treatment Most adverse effects are mild to moderate and include GI disturbances, weight loss, hyperbilirubinaemia, anaemia and transient ALT increases
REP 2139-Ca	Nucleic acid polymer	Inhibits viral entry Interaction with amphipathic protein domains interrupts viral replication	Intravenous infusion	Phase II	When administered as part of a regime including Peg-IFN-alpha, 75% of patients were HDV RNA negative at end of treatment Tolerable adverse effects

ALT = alanine transaminase; GI = gastrointestinal; HCV = hepatitis D virus; IFN = inteferon; PEG = pegylated.