A Phase 2 interventional study of lonafarnib and Ritonavir in Chronic Delta Hepatitis, sponsored by EIT Pharma, Inc.. Completed. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-09-25.
Sponsored by EIT Pharma, Inc. · Phase 2, Interventional, and Treatment
A phase 2, open-label study to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamic activity of titrating-dose lonafarnib/ritonavir in patients chronically infected with hepatitis delta virus (HDV)
This is a Phase 2 study of 24 weeks of treatment with a dose-titration regimen of lonafarnib/ritonavir in up to 15 patients chronically infected with HDV: lonafarnib starting at 50 mg twice daily (BID) in combination with ritonavir 100 mg BID and escalating lonafarnib as tolerated.
The duration of the study for each patient is approximately 13 months (up to 4 weeks for screening, 24 weeks of treatment, 4 weeks for the primary follow-up visit, and monthly safety follow-up visits for 5 months thereafter). The 6-month follow-up after the last dose of study drug is designed to allow evaluation of the clinical and virologic course after completion of the 24-week Treatment Period.
43 studies on the registry are indexed under Hepatitis D, Chronic; 9 are open to participants now.
This study's enrollment of 15 is below the median of 46 across 30 interventional studies indexed under Hepatitis D, Chronic.
Browse Hepatitis D, Chronic studies →EIT Pharma, Inc. is the lead sponsor of 4 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Key Exclusion Criteria:
Concomitant use of any of the following:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CYP3A (CYP3A4) inhibitors and inducers
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Lonafarnib starting at 50 mg BID in combination with ritonavir 100 mg BID and escalating to lonafarnib 75 mg BID and then 100 mg BID as tolerated. The duration of the study for each patient is 6 months of treatment and 6 months follow-up.
Drug: lonafarnib · Drug: Ritonavir
antiviral farnesyltransferase inhibitor
Also known as: EBP994, Sarasar
Cytochromes P450 3A4 inhibitor used to boost lonafarnib
Also known as: Norvir
Change From Baseline to Week 24 in Mean Hepatitis D Virus (HDV) Ribonucleic Acid (RNA) Titer
Change from baseline to Week 24 in mean HDV RNA titer following dose escalating from lonafarnib 50 mg BID to 75 mg BID and to 100 mg BID, all boosted with ritonavir 100 mg BID.
Time frame: Baseline and Week 24 (6 months)
Number of Patients With 1 Log Reduction From Baseline by Timepoint
Number of patients with at least 1 log reduction in HDV RNA from baseline by dose level and timepoint
Time frame: Baseline and Week 1, Week 2, Week 4, Week 6, Week 8, Week 12, Week 16, Week 20, or Week 24
| Milestone | Lonafarnib/Ritonavir |
|---|---|
| Started | 15 |
| Completed | 13 |
| Not completed | 2 |
| Withdrew: Adverse event | 1 |
| Withdrew: Adverse event | 1 |
Change from baseline to Week 24 in mean HDV RNA titer following dose escalating from lonafarnib 50 mg BID to 75 mg BID and to 100 mg BID, all boosted with ritonavir 100 mg BID.
| log IU/mL | Lonafarnib/Ritonavir |
|---|---|
| Change From Baseline to Week 24 in Mean Hepatitis D Virus (HDV) Ribonucleic Acid (RNA) Titer | -1.62 ± 1.4 |
Number of patients with at least 1 log reduction in HDV RNA from baseline by dose level and timepoint
| Participants | Lonafarnib/Ritonavir |
|---|---|
| Week 1 | 7 |
| Week 2 | 6 |
| Week 4 | 10 |
| Week 6 | 11 |
| Week 8 | 10 |
| Week 12 | 12 |
| Week 16 | 12 |
| Week 20 | 10 |
| Week 24 | 9 |
Collected over 6 months on treatment, 6 months off-treatment follow-up.. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Lonafarnib/Ritonavir | 0/15 (0%) | 1/15 (6.7%) | 15/15 (100%) |
| Event | Lonafarnib/Ritonavir |
|---|---|
| mandibular fracture)Injury, poisoning and procedural complications | 1/15 |
| Event | Lonafarnib/Ritonavir |
|---|---|
| DiarrheaGastrointestinal disorders | 15/15 |
| NauseaGastrointestinal disorders | 8/15 |
| VomitingGastrointestinal disorders | 8/15 |
| Weight DecreaseInvestigations | 8/15 |
| Decrease AppetiteMetabolism and nutrition disorders | 8/15 |
| Abdominal PainGastrointestinal disorders | 6/15 |
| FatigueGeneral disorders | 4/15 |
| DysgeusiaNervous system disorders | 4/15 |
| DizzinessNervous system disorders | 4/15 |
| AstheniaGeneral disorders | 3/15 |
| Age, Continuous(years) | Lonafarnib/Ritonavir |
|---|---|
| Mean | 42 ± 12.6 |
| Sex: Female, Male(Participants) | Lonafarnib/Ritonavir |
|---|---|
| Female | 4 |
| Male | 11 |
| Ethnicity (NIH/OMB)(Participants) | Lonafarnib/Ritonavir |
|---|---|
| Hispanic or Latino | 0 |
| Not Hispanic or Latino | 15 |
| Unknown or Not Reported | 0 |
| Race (NIH/OMB)(Participants) | Lonafarnib/Ritonavir |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 2 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 1 |
| White | 12 |
| More than one race | 0 |
| Unknown or Not Reported | 0 |
No study locations are listed for this record.
PDFs hosted by the registry, ClinicalTrials.gov.
The record gives a start of Sep 2015, a primary completion of Aug 2016 and a completion of Feb 2017. It does not say whether these dates are actual or estimated.
Results were first posted in Jun 2023, 6 years 10 months after primary completion. A results delay was requested in Feb 2018.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in May 2023. You cannot join it, but the record below documents what was studied.
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Studies of the drugs tested here: Lonafarnib · Ritonavir
EIT Pharma, Inc.