Category Archives: Hepatology

Big Interferon-free Hepatitis C Study

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Every week there is more information on clinical trials for hepatitis C; I am waiting for this to translate into improvements for the pediatric population.

This week’s biggest publication: NEJM 2013; 369: 630-9.  This was a phase 2b randomized open-label trial of faldaprevir (a NS3/4A protease inhibitor) in combination with deleobuvir (a non nucleoside NS5B polymerase inhibitor).  In total, 5 different regimens were examined, most in combination with ribavirin.  The authors recruited 362 HCV genotype 1 patients who were randomized into these treatment groups & he sustained virologic response 12 weeks after completion of therapy

  • Faldaprevir 120 daily, deleobuvir 600 three times a day, and ribavirin for 16 weeks (TID16W) –>59%
  • Faldaprevir 120 daily, deleobuvir 600 three times a day, and ribavirin for 28 weeks (TID28W) –>59%
  • Faldaprevir 120 daily, deleobuvir 600 three times a day, and ribavirin for 40 weeks (TID40W) –>52%
  • Faldaprevir 120 daily, deleobuvir 600 two times a day, and ribavirin for 28 weeks (BID28W) –>69%
  • Faldaprevir 120 daily, deleobuvir 600 three times a day, without ribavirin for 28 weeks  (TID28W-NR) –>39%

Rates of SVR were higher among genotype 1b, 56-85%, compared with 1a, 38-43% (when excluding non-ribavirin group).  Genotype 1a patients with IL28B CC had similar response (58-84%) to genotype 1b patients.  Genotype 1a patients were much more likely to relapse if not treated for at least 28 weeks.

Adverse effects were common and reported in 94% of participants; 9% had severe adverse reactions.  Gastrointestinal and dermatologic advents events were the most frequent.  Also, faldaprevir resulted in jaundice (unconjugated hyperbilirubinemia) in many patients (16-28% of patients who took ribavirin in their regimens).

This large study showed that when these oral antiviral are used in combination with ribavirin that results are similar to current standard of care treatments for adult patients.  For telaprevir or boceprevir, along with pegylated interferon and ribavirin, phase 3 trials showed SVRs between 68-75%.

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Data on Chelators for Wilson Disease

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A recent retrospective analysis on 405 patients with Wilson disease analyzed the efficacy and safety of oral chelators for Wilson disease (Clin Gastroenterol Hepatol 2013; 11: 1028-35).

The authors noted that there were frequent changes in medication; in total, 471 monotherapies were analyzed: 326 patients with D-penicillamine (DPA) and 141 with trientine.  Trientine was a first line treatment in only 38 patients.  About 50% of patients presented with hepatic symptoms, about 20% neurologic symptoms, about 15% with combined hepatic/neurologic symptoms and the remainder, ~10%, were asymptomatic.

  • 9 of 326 with DPA and 3 of 141 with trientine underwent liver transplantation.
  • Adverse effects were more common with DPA, including arthralgias (8.9%), proteinuria (6.1%), ANA antibodies (6.7%), gastric complaints (2.5%) and polyneuropathy (1.8%).  28.8% of DPA stopped therapy due to adverse effects.
  • Adverse effects with trientine resulted in stopping treatment in 7.1% and included arthralgias in 2.8%, and gastric complaints in 1.4%.
  • Hepatic improvements were observed in >90%

The authors summarize their findings:

“Both DPA and trientine were equally and highly effective in controlling liver disease…In light of recent reports of hepatic deterioration under zinc therapy, the current data emphasize the role of these chelating agents in the treatment of symptomatic hepatic patients.”

Related blog post:

Finding the Right Specialist | gutsandgrowth This post has link to AASLD guidelines for Wilson disease.

Emerging Targets for Hepatitis C -Part 2

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The best review on new therapies for HCV that I’ve read in quite a long time:

Hepatology 2013; 58: 428-38

First the abbreviations:

  • ASV -Asunaprevir
  • BOC -boceprevir
  • DAA -direct-acting antiviral
  • DCV -daclatasvir
  • DNV -danoprevir
  • NI -nucleos(t)ide inhibitor
  • NNI -nonnucleos(t)ide inhibitor
  • SIL -silibinin
  • SOF -sofosbuvir
  • TVR -telaprevir

More terminology:

  • First-generation NS3/4A protease inhibitors (TVR, BOC) are “defined as agents that display potent activity on HCV-1 but oppose a low barrier to selection of resistant viral variants and are not effective on all viral genotypes.”
  • Second generation NS3/4A protease inhibitors are “defined as agents that pose a high barrier to the development of viral resistance, retain activity against the viral variants that are resistant to first-generation compounds, and are active across all HCV genotypes.”
  • First-wave therapies are covalent linear inhibitors and second-wave therapies are either non covalent linear or macrocyclic inhibitors.

What are the weapons?

Some second-wave, first generation NS3/4A PIs: faldaprevir, asunaprevir, sovaprevir, simeprevir, danoprevir, and vaniprevir.  These agents have similar clinical efficacy as BOC and TVR but are easier to administer, usually once-a-day.  Some of these agents have better activity  against several genotypes.

MK-5172, 2nd-generation NS3/4A PI,  has pan-genotype activity & maintains antiviral activity against most mutations that confer resistance to 1st-generation PIs.

DCV, a NS5A inhibitor, has potent HCV activity but a low barrier for viral resistance; thus, it is likely to be used in combination with other agents.  Multiple NS5A inhibitors are in development.

SOF, a NS5B polymerase inhibitor, is being studied in interferon-free combinations.  Viral resistance has been rare in clinical studies with this agent.  Multiple other agents in this class are in study.

NS5B polymerase inhibitor NNIs bind to less conserved sites on HCV; thus, initial results have not been as promising.  Several NNIs, including setrobuvir and lomibuvir (& others), are being tested in combination in all-oral, interferon-free regimens.

SIL, a NS4B binding inhibitor, is an intravenous agent that has shown some efficacy in liver transplant patients.  Other oral agents, like clemizole, are being investigated.

How these agents may be useful:

  1. “The first step forward in anti-HCV therapy will be the introduction of a second-wave PI to used in combination with PEG-IFN/RBV.” Simeprevir, faldaprevir, and ritonavir-boosted danoprevir (DNV) will be easier to administer than TVR or BOC as they can be given once-daily.  In addition, these drugs are more active against genotypes 2, 4, 5, and 6.  In fact, ritonavir-boosted DNV in combination with PEG-IFN/RBV had 100% SVR efficacy for patients with HCV-4 in one trial.
  2. Next, will be NS5A and NS5B inhibitors to be used in combination with previous agents.  These agents will compete with second-wave PIs but “whether they will provide a true innovation in terms of viral cure rates, safety profile, or patient tolerability is still to be demonstrated.”  These agents work better with other DAAs.
  3. Finally, all-oral combinations will enter the market.  “The first all-oral anti-HCV regimen will be likely available in 2014 for HCV-2 and HCV-3 patients.”  SOF with RBV has had good success rates in previous studies.

Potential Problems:

  • Many of these investigational agents have been studied in easy-to-cure populations.
  • Lack of data in advanced fibrosis/cirrhosis.
  • Safety questions in post-transplant populations.
  • Affordability.  “It is possible that these innovative regimens will be confined to groups of patients in whom TVR/BOC or PEG-IFN/RBV are either ineffective or unsafe.”  Some patients may receive ‘maginally less effective and less tolerable drugs for cost-containing issues.’
  • Drug resistance.  This is likely to become a clinical problem with all oral IFN-free regimens. with TVR/BOC, resistance has limited significance due to HCV quasispecies reverting back to wild-type virus after stopping TVR or BOC.  It is unclear if this will be the case with other DAAs.

 

 

Emerging Targets for Hepatitis C -Part 1

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The latest advances in hepatitis C are related in several recent publications:

  1. Hepatology 2013; 57: 2143-54.
  2. Hepatology 2013; 57: 2155-63.
  3. Clin Gastroenterol Hepatol 2013; 11: 612-619.

The first two studies provide specific information about the effectiveness of Faldaprevir combined with peginterferon alfa-2a/ribavirin (PEG/RBV) in treatment-naive patients and patients with prior nonresponse respectively.  The third reference provides the big picture regarding all of the emerging treatments.

In the first study, the “SILEN-C1” phase 2 trial, 429 patients without cirrhosis were randomized to several treatment arms.  423 of the 429 patients were genotype 1.  This large study involved 89 centers in 15 countries.  All of the treatment groups received PEG/RBV along with either placebo, faldaprevir 120 mg with lead-in (LI), faldaprevir 240 mg LI and faldaprevir 240 mg without LI.   Faldaprevir is a NS3/4A protease inhibitor which can be administered orally once a day.  Results: SVR achieved in 56% (placebo), 72% (faldaprevir 120mg LI), 72% (faldaprevir 240 mg LI), and 84% (faldaprevir 240 mg without LI).  Discontinuation rates were 1%, 4%, 11%, and 5% for the aforementioned treatment groups.

In the second study, the “SILEN-C2” trial, 290 non cirrhotic genotype 1 patients with either no response or partial response to previous treatment underwent a 48 week treatment trial with a similar design as the SILEN-C1. Results: SVR rates among partial responders were 32% (faldaprevir 240 mg LI), 50% (faldaprevir 240 mg without LI), and 42%(faldaprevir 240 mg BID/LI).  Among null responders, SVR rates were 21% (faldaprevir 240 mg LI), 35% (faldaprevir 240 mg without LI), and 29% (faldaprevir 240 mg BID/LI).  Adverse reactions were higher in those on higher doses and included anemia, rash, indirect hyperbilirubinemia, and nausea. Discontinuation rates were 6%, 4%, and 23% for the aforementioned treatment groups.

The third study provides a landscape of current treatment and emerging treatments.  Given the improvement in SVR among genotype 1 patients, the use of either telaprevir or boceprevir in combination with PEG/RBV is the “new standard of care” among adult patients with HCV.  Studies supporting telaprevir include the ADVANCE study, the REALIZE trial, and the OPTIMIZE study.  For boceprevir, its effectiveness was demonstrated with SPRINT-2, and RESPOND-2.

Both boceprevir and telaprevir, are NS3/4A serine protease inhibitors and are considered direct acting antivirals (DAAs). On the horizon:

  • Simeprevir -NS3/4A protease inhibitor.  Studies: PILLAR, ASPIRE.  SVR: 75-86% in treatment-naive patients. Once daily, no rash or increased anemia.  Hyperbilirubinemia can occur.
  • Faldaprevir -see above studies.
  • Danoprevir -NS3/4A protease inhibitor. Study: DAUPHINE. For genotypes 1 and 4. 100% SVR in genotype 4.  Rates of withdrawal with danoprevir were similar to placebo.
  • Daclatasvir -NS5A replication inhibitor. Study: COMMAND-1. For genotypes 1 and 4.
  • Sofosbuvir -NS5B polymerase inhibitor. Studies: PROTON, ATOMIC. For genotypes 1, 4, and 6.
  • Multiple DAAs in combination. Studies: MATTERHORN, INFORM-SVR, AVIATOR, ELECTRON, SOUND-2

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Tattoos: a marker for Hepatitis C

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A recent study has found that tattooing was independently associated with hepatitis C virus (HCV) infection, even in those without traditional risk factors (Hepatology 2013; 57: 2117-23).

The authors of this large, multicenter, case-control study analyzed demographics and risk factors for HCV among 3,871 patients including 1,930 who had chronic HCV infection.  As in previous studies, a history of injection drug use (IDU) and blood transfusion prior to 1992 were associated with an increased risk of HCV.

After excluding patients with these risk factors, there were 465 patients with HCV and 1,421 controls.  Among these individuals, after controlling for age, sex and ethnicity, HCV-positive patients had an OR of 5.17 of having had one or more tattoos compared to the control patients.

Previous studies have not been definitive about whether tattoos represent a specific risk factor or an epiphenomenon.  That is, tattoos are known to be more common among individuals with IDU.  And, this study does not really settle the question either.  “Underrepresentation due to self-reporting of intravenous drug use is a concern that could confound our result.”  In addition, the authors note that commercial parlors have not been implicated in HCV transmission.

Bottomline: Individuals with tattoos are more likely to have HCV.  For individuals who insist on tattoos, avoid nonprofessional settings to limit the risk of HCV acquisition.

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Neutrophil function as a biomarker for Acute Liver Failure

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More data on impaired neutrophil function in acute liver failure (ALF) and subacute liver failure (SALF) is available (Hepatology 2013; 57: 1142-52).

This study examined 15 ALF patients and 10 SALF patients in a cross-sectional case-control cohort design who were admitted to the liver ICU at King’s College Hospital between 2008-2010.  The median age for the ALF group was 33 and for the SALF group it was 52.5.  Ultimately 10 survived without liver transplantation; the remainder either died or underwent liver transplantation.

Neutrophil function was assessed on admission and then serially every 3-4 days in several ways; these assays were compared with 6 septic controls and 11 healthy controls.  Phagocytic activity was measured with a “Phagotest,” which quantifies opsonization of labeled E. coli. Oxidative burst was measured with the “Burtest,” which determines the percentage of phagocytic cells that produce a reactive oxygen species.  Other tests examined neutrophil phenotype and cytokine measurements (TNF-α, IL-1β, IL-6, CXC8/IL-8, IL-10, and IL-17).

Key findings:

  • Impaired neutrophil phagocytic activity in both ALF and SALF cohort on admission predicted non survival without liver transplant (p=0.01).
  • Neutrophil expression of CD-16 was significantly reduced in ALF cohort on day 1 (p<0.001).

Take-home message:

This study demonstrates specific defects in neutrophil function in ALF/SALF that are similar to impaired bactericidal function in severe sepsis.  Neutrophil function assays, while not available at the bedside at this time, are important biomarkers in ALF/SALF for increased susceptibility for sepsis and death.

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Hepatocellular Carcinoma after the Fontan Procedure

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Given the fact that chronic liver disease and cirrhosis can develop in patients after the Fontan procedure, it comes as little surprise that cases of hepatocellular carcinoma (HCC) are being reported as well (NEJM 2013; 368: 1756-57).

This letter to editor describes four patients ages 24 to 42 who developed HCC following a classic Fontan or a variation.  Three of the four had very elevated alpha-fetoprotein levels; the lowest of the four patients was 106 ng/mL.  The letter notes that cirrhosis “may develop…approximately 11 to 15 years after a Fontan procedure; an incidence of cancer of 1.5 to 5.0% per year” is estimated after development of cirrhosis based on previous studies.

The letter also describes difficulties with regard to potential screening and treatment.

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Once Daily Tacrolimus for Liver Transplant Recipients

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A recent study shows that once daily tacrolimus can be effective in patients who have been stable following liver transplantation (LT) (Liver Transplantation 2013; 19: 529-33).

In this retrospective, single center study with 394 adult LT patients, the authors examined the results of conversion to once daily dosing of tacrolimus.  Patient demographics noted an mean age of 53 years & mean time post-transplant was 74 months.

Criteria for conversion:

  1. At least 6 months posttransplant
  2. No rejection in >3 months
  3. Tacrolimus bid was changed to the same total daily dose at once a day and then modified based on levels.

Results after a 24 month followup:

  • 358 of 394 were able to maintain once a day dosing. 6 patients had been converted to cyclosporine, 14 patients had stopped all calcineurin inhibitors, 16 patients had returned to BID dosing.
  • Acute rejection episode was noted in 7 patients
  • Mean serum tacrolimus trough decreased after conversion from 6.1 to 4.9 ng/mL

Take-home message:

Once daily tacrolimus appears to be a reasonable strategy for stable LT patients.  It is possible that once daily administration will improve adherence.

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More HCV options -phase 3 for Sofosbuvir

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The pace of research for HCV is incredible.  Two months ago phase 2 data for Sofosbuvir were reported and noted on this blog (More options for Hepatitis C | gutsandgrowth).  Now phase 3 data from multiple trials have emerged indicating the effectiveness of sofosbuvir for all HCV genotypes.

In the first study, NEJM 2013; 368: 1867-77, data from two trials (POSITRON and FUSION) of patients with HCV genotypes 2 and 3 are reported.  The POSITRON trial (63 sites, n=278 received treatment) was a blinded placebo-controlled study that evaluated 12 weeks of sofosbuvir/ribavirin compared with placebo in patients who discontinued interferon due to unacceptable adverse events or could not take interferon due to contraindications (most commonly psychiatric disorder or autoimmunity). Results: sustained virological response (SVR) in 78% of treatment group compared with 0% of placebo patients.  In addition, there was “complete concordance (100%) between rates of SVR at 12 weeks and at 24 weeks.”

The FUSION study (67 sites, n=201 received treatment) was a blinded, active-control study in patients who did not respond to a previous interferon-based regimen; one of two treatment regimens were administered: 12 weeks of sofosbuvir/ribavirin followed by placebo or 16 weeks of sofosbuvir/ribavirin. Results: 93% of genotype 2 patients had SVR and 61% of genotype 3 patients had SVR.  Among cirrhotic patients, 61% had SVR (94% of genotype 2, 21% of genotype 3); for those without cirrhosis, there was an 81% SVR (92% with genotype 2, 68% with genotype 3).  Thus, it is easy to conclude that genotype 3 patients with cirrhosis responded much less favorably.

Other important findings: rates of discontinuation among the treatment groups were similar to the placebo groups.  The most common adverse effect was anemia in the treatment groups.

In the second study, NEJM 2013; 368: 1878-87, an additional two phase 2 trials (NEUTRINO and FISSION) are reported from previously untreated chronic HCV patients.  The first trial (NEUTRINO) was an open-label study examining a 12-week regimen of sofosbuvir, peginterferon alfa-2a, and ribavirin in 327 HCV patients (98% genotypes 1 or 4).  Results: SVR noted in 90%. The second trial (FISSION) enrolled 499 patients with genotypes 2 and 3 who randomly received either peginterferon alfa-2a/ribavirin for 24 weeks or sofosbuvir/ribavirin for 12 weeks. Results: SVR noted to be 67% in both groups.  Genotype 2 patients again fared better than genotype 3 among the sofosbuvir/ribavirin group (97% versus 56%).  Some adverse events like fatigue, headache and nausea were common.  Overall, side effects were much lower in those not receiving peginterferon (see Table 3).

Take home message: From the editorial (pg 1931-32 in same issue): “a radical change in clinical practice is imminent…the low incidence of side effects, the relatively short duration of treatment, and the pangenotypic properties of the drugs are strong selling points of a sofosbuvir-ribavirin regimen and will probably lower the threshold for HCV treatment for both patients and physicians.”

Hopefully, we will see pediatric studies soon.

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