Lonafarnib-based regimens demonstrated statistically significant improvements in week 48 composite virologic and biochemical response rates compared with placebo.
The Food and Drug Administration (FDA) has accepted for review the New Drug Application (NDA) for lonafarnib for the treatment of chronic hepatitis D
Lonafarnib is an investigational, oral farnesyltransferase inhibitor. It is expected to reduce viral activity in patients with chronic hepatitis D by inhibiting the prenylation-dependent assembly pathway required to form new hepatitis D virus (HDV) virions.
The NDA is supported by phase 1/2 clinical data, nonclinical data, manufacturing information, as well as the phase 3 D-LIVR trial (ClinicalTrials.gov Identifier: NCT03719313). The D-LIVR study evaluated the safety and efficacy of lonafarnib plus ritonavir (LNF/RTV), with or without pegylated interferon-alfa-2a (PEG), in adults infected with HDV receiving anti-HBV nucleos(t)ide maintenance therapy.
Study participants (N=407) were randomly assigned to receive oral LNF/RTV twice daily (n=178), oral LNF/RTV twice daily plus subcutaneous (SC) PEG once weekly (n=125), SC PEG monotherapy once weekly (n=52), or placebo (n=52). The primary endpoint was the composite of virologic response (≥2log10 reduction in HDV RNA from baseline) and biochemical response (alanine aminotransferase [ALT] normalization relative to baseline) at week 48
Results showed treatment with LNF/RTV and LNF/RTV plus PEG demonstrated statistically significant improvements in the primary composite endpoint compared with placebo. At week 48, 10.1% of patients in the LNF/RTV arm (P <.001) and 19.2% in the LNF/RTV plus PEG arm (P <.0001) achieved the primary composite endpoint vs 1.9% of those receiving placebo.
Findings also showed that 44.4% of week 48 composite responders in the LNF/RTV arm and 41.7% in the LNF/RTV plus PEG arm maintained that response after a 24-week follow-up period without treatment.
Notably, 24.7% and 34.4% of patients treated with LNF/RTV and LNF/RTV plus PEG, respectively, also achieved ALT normalization after 48 weeks; this effect was sustained after an additional 24 weeks off treatment. Histological response (≥2-point improvement in Histological Activity Index score and no worsening of fibrosis by Ishak score, as determined by blinded assessment of paired liver biopsies) was also achieved in 53% of patients in the LNF/RTV plus PEG treatment group.
The most common adverse reactions reported with LNF/RTV, with or without PEG, were mild to moderate gastrointestinal events. Serious adverse reactions were observed in 8.4% of LNF/RTV patients, 14.4% of LNF/RTV plus PEG patients, and 3.6% of patients who received placebo.
“Patients living with chronic hepatitis D urgently need novel therapies that target distinct steps in the HDV lifecycle,” said Dr Jeffrey Glenn, co-founder of EIT Pharma and Joseph D. Grant Professor and Professor of Medicine and Microbiology & Immunology at Stanford University. “The FDA’s acceptance of the NDA is an important first step towards getting patients with CHD a new treatment option for this serious, life-threatening disease, and we look forward to working closely with the FDA throughout the review process.”
This article originally appeared on MPR
- EIT Pharma announces FDA acceptance of New Drug Application for lonafarnib for treatment of chronic hepatitis D. News release. EIT Pharma. August 11, 2026.https://www.prnewswire.com/news-releases/eit-pharma-announces-fda-acceptance-of-new-drug-application-for-lonafarnib-for-treatment-of-chronic-hepatitis-d-302847501.html.
- Taylor R, Etzion O, Hamid SS, et al.Lonafarnib/ritonavir with or without peginterferon achieves rapid, durable responses in chronic hepatitis D: extended analyses from the phase 3 D-LIVR trial.Poster presented at: European Association for the Study of the Liver (EASL) Congress; May 27, 2026; Barcelona, Spain.


