Prevalence of resistance-associated substitutions and retreatment of patients failing a glecaprevir/pibrentasvir regimen

OBJECTIVES

To investigate resistance-associated substitutions (RASs) as well as retreatment efficacies in a large cohort of European patients with failure of glecaprevir/pibrentasvir.

METHODS

Patients were identified from three European Resistance Reference centres in Spain, Italy and Germany. Sequencing of NS3, NS5A and NS5B was conducted and substitutions associated with resistance to direct antiviral agents were analysed. Clinical and virological parameters were documented retrospectively and retreatment efficacies were evaluated.

RESULTS

We evaluated 90 glecaprevir/pibrentasvir failures [3a (n = 36), 1a (n = 23), 2a/2c (n = 20), 1b (n = 10) and 4d (n = 1)]. Ten patients were cirrhotic, two had previous exposure to PEG-interferon and seven were coinfected with HIV; 80 had been treated for 8 weeks. Overall, 31 patients (34.4%) failed glecaprevir/pibrentasvir without any NS3 or NS5A RASs, 62.4% (53/85) showed RASs in NS5A, 15.6% (13/83) in NS3 and 10% (9/90) in both NS5A and NS3. Infection with HCV genotypes 1a and 3a was associated with a higher prevalence of NS5A RASs. Patients harbouring two (n = 34) or more (n = 8) RASs in NS5A were frequent. Retreatment was initiated in 56 patients, almost all (n = 52) with sofosbuvir/velpatasvir/voxilaprevir. The overall sustained virological response rate was 97.8% in patients with end-of-follow-up data available.

CONCLUSIONS

One-third of patients failed glecaprevir/pibrentasvir without resistance. RASs in NS5A were more prevalent than in NS3 and were frequently observed as dual and triple combination patterns, with a high impact on NS5A inhibitor activity, particularly in genotypes 1a and 3a. Retreatment of glecaprevir/pibrentasvir failures with sofosbuvir/velpatasvir/voxilaprevir achieved viral suppression across all genotypes.

[Coincidence of a chronic Hepatitis C and an autoimmune Hepatitis Type 3 - successful therapy with the new direct-acting antiviral agents]

Chronic hepatitis C infection may be associated with several features of autoimmunity (i. e., detection of different kinds of autoantibodies in the serum). Hepatitis C is also associated with different autoimmune diseases, such as autoimmune thyroiditis, lichen ruber planus, and membranous glomerulonephritis being the most relevant. There are very few cases of a coincidence of chronic hepatitis C with an autoimmune hepatitis, that is usually diagnosed by detection of specific autoantibodies and typical histological features. During the time of interferon-based antiviral therapies, we often faced a therapeutic dilemma as interferon could lead to an exacerbation of the coincident autoimmune disease. So, in these cases, a prophylactic immunosuppression had to be started before initiation of interferon therapy. Meanwhile, in the new era of direct antiviral agents against hepatitis C, highly specific and effective therapeutic options are available. The case report presented here describes the very rare coincidence of a chronic hepatitis C, genotype 1 with an autoimmune hepatitis type 3 diagnosed by the presence of anti-SLA-antibodies. In the past, the patient had several unsuccessful interferon-based therapies without achieving a sustained virological response in parallel with an immunosuppressive treatment with azathioprine. During the further course of the disease, the patient generated a liver cirrhosis CHILD A after only a few years. After the approval of the direct antiviral agents sofosbuvir and daclatasvir in 2014, we conducted an antiviral therapy, including ribavirin, for 24 weeks and fortunately achieved a sustained virological response. Due to the persistent disease activity caused by the autoimmune hepatitis after the end of antiviral therapy, we treated the patient with prednisolone and azathioprine and could induce a stable and persistent remission of the autoimmune disease.

Severe agranulocytosis as a rare side effect of pegylated interferon therapy for chronic hepatitis B

We report on a 19-year-old male patient with chronic HBeAg-positive hepatitis B-infection and agranulocytosis as a severe side effect of pegylated interferon alpha therapy. Within the first six months of therapy the hepatitis B virus DNA became undetectable in parallel with a significant decrease of the HBsAg serum concentration. After a six-month course of therapy the patient was admitted to our emergency unit. He appeared significantly ill and reported that he had fever for two days, painful oral mucosa, throat pain and general fatigue and discomfort. A complete blood cell count was performed and revealed a complete agranulocytosis with no detectable neutrophilic granulocytes in the blood smear. Antiviral therapy was immediately stopped and he was admitted to our clinic where a supportive therapy and an empirical course of broadband antibiotics were initiated. A few days later an additional treatment with intravenous prednisolone was started. Within the next week the agranulocytosis resolved and the neutrophil count was completely restored. In parallel, the clinical status improved quickly. This case demonstrates the need for our awareness of agranulocytosis as a rare but severe and potentially life-threatening side effect of interferon alpha therapy.

[A 40-year-old female patient with seronegative autoimmune hepatitis following a newly acquired hepatitis B infection]

We report the case of a 40-year-old female patient admitted at our clinic because of recent onset jaundice and elevated transaminases. Two months before admission the patient had unprotected sexual contact with a potential hepatitis B-infected man. Virological screening performed in our clinic revealed IgM antibodies against hepatitis B virus core protein (anti-HBc-IgM) and elevated HBV-DNA. Our first diagnosis was an acute hepatitis B virus infection. During her stay at our clinic the patient achieved HBe seroconversion and a loss of HBV-DNA. Nevertheless the transaminases remained high and jaundice persisted. The histological examination of the liver biopsy showed interface hepatitis with plasma cells as the characteristic signs of autoimmune hepatitis. On that basis we started an immunosuppressive therapy with prednisolone in parallel with a prophylactic lamivudine therapy and after two weeks there was a complete resolution of jaundice and a normalisation of transaminases. In conclusion, we present a rare case report of an autoimmune hepatitis as a result a newly acquired hepatitis B infection. This case report highlights the relationship between viral infection and autoimmunity within the liver.