Low Rate of Hepatitis B Reactivation Among Patients with Chronic Hepatitis C During Direct Acting Antiviral Therapy

BACKGROUND AND AIMS

Hepatitis B virus (HBV) reactivation has been reported in patients co-infected with hepatitis C virus (HCV) during direct acting antiviral (DAA) therapy, leading the United States Food and Drug Administration (U.S. FDA) to issue a black box warning on all DAA drug labels recommending monitoring for HBV reactivation. We conducted a comprehensive evaluation to assess the rate of HBV reactivation among patients with chronic hepatitis C (CHC) during DAA therapy.

METHODS

Patients with CHC and recovered HBV infection (hepatitis B surface antigen negative (HBsAg)/anti-hepatitis B core positive), treated with DAAs were included if stored sera were available. Samples were tested for HBV DNA, HBsAg, and ALT. HBV reactivation was considered if (1) HBV DNA was undetectable pre-DAA therapy and became detectable post-therapy, or (2) HBV DNA was detectable pre-treatment, but not quantifiable (< 20 IU/mL) and became quantifiable post-treatment.

RESULT

79 patients with median age of 62 years were included. 68% were male and Caucasian. Various DAA regimens were administered for 12-24 weeks. Reactivation occurred in 8/79 (10%) of patients and occurred more frequently in men compared to women: 6 during treatment and 2 after treatment. Neither an ALT flare nor HBsAg seroreversion were observed. Detectable HBV DNA was transient in 5/8 and could not be determined in 3/8 but ALT flares were not observed in follow-up of these patients.

CONCLUSION

The risk of HBV reactivation was low in CHC patients with resolved HBV during DAA therapy. Our data support testing for HBV DNA only in selected patients with ALT flares or failure of ALT normalization during DAA treatment.

Durability of Spontaneous and Treatment-Related Loss of Hepatitis B s Antigen

BACKGROUND & AIMS

Clearance of hepatitis B surface antigen (HBsAg) from serum is the most desirable end point and a proposed definition of functional cure for hepatitis B virus (HBV) infection. However, little is known about the long-term durability of HBsAg loss, and there is controversy over whether the development of antibodies against HBsAg (anti-HBs) is required for maintenance. We aimed to assess the durability of spontaneous or treatment-related (interferon or nucleos(t)ide analogue [NA]) loss of HBsAg.

METHODS

We performed a retrospective study of patients with chronic HBV infection followed up at the National Institutes of Health from February 1980 through November 2017. We identified those with HBsAg loss, confirmed on 2 visits at least 24 weeks apart. Patients with hepatitis C virus, hepatitis D virus, human immunodeficiency virus, or human T lymphocyte virus co-infection or HBsAg loss after liver transplantation were excluded. Patients were assigned to the following groups: spontaneous clearance (cleared HBsAg without ever receiving treatment or those who received treatment with a NA or interferon and discontinued therapy >5 years before HBsAg loss), interferon-treated (cleared HBsAg either during treatment or ≤5 years after stopping interferon), and NA-treated (cleared HBsAg either during treatment or ≤5 years after stopping NA).

RESULTS

Among the 787 HBsAg-positive patients, 89 achieved HBsAg loss; 65 of 89 had confirmed HBsAg loss, which was spontaneous in 19 of the patients (29%), after interferon in 22 (34%), and after NA in 24 (37%). Of the 65 patients with confirmed loss of HBsAg, 62 patients (95%) remained HBsAg negative after a mean time of 9.6 years from the first negative HBsAg test result. HBsAg seroreversion occurred in 3 of the 46 treated patients (7%) (1 interferon and 2 NA), 1 of whom was positive for anti-HBs. At the time of HBsAg loss, 33 of 65 (51%) were anti-HBs positive. At the last follow-up evaluation, anti-HBs was detectable in 50 of the 62 patients (81%) assessed. The rate of development of anti-HBs was proportionally higher among interferon-treated patients (19 of 21; 90%) than NA-treated patients (17 of 22; 77%) or patients with spontaneous loss of HBsAg (14 of 19; 74%).

CONCLUSIONS

In a retrospective study of 787 HBsAg-positive patients, loss of HBsAg (either spontaneous or after treatment) was confirmed in 8% and was durable. Seroconversion to anti-HBs increased over time and appeared to be more frequent after interferon treatment. HBsAg loss is therefore a robust end point for functional cure.

The HLA class II Allele DRB1*1501 is over-represented in patients with idiopathic pulmonary fibrosis

Background

Idiopathic pulmonary fibrosis (IPF) is a progressive and medically refractory lung disease with a grim prognosis. Although the etiology of IPF remains perplexing, abnormal adaptive immune responses are evident in many afflicted patients. We hypothesized that perturbations of human leukocyte antigen (HLA) allele frequencies, which are often seen among patients with immunologic diseases, may also be present in IPF patients.

Methods/Principal Findings

HLA alleles were determined in subpopulations of IPF and normal subjects using molecular typing methods. HLA-DRB1*15 was over-represented in a discovery cohort of 79 Caucasian IPF subjects who had lung transplantations at the University of Pittsburgh (36.7%) compared to normal reference populations. These findings were prospectively replicated in a validation cohort of 196 additional IPF subjects from four other U.S. medical centers that included both ambulatory patients and lung transplantation recipients. High-resolution typing was used to further define specific HLA-DRB1*15 alleles. DRB1*1501 prevalence in IPF subjects was similar among the 143 ambulatory patients and 132 transplant recipients (31.5% and 34.8%, respectively, p = 0.55). The aggregate prevalence of DRB1*1501 in IPF patients was significantly greater than among 285 healthy controls (33.1% vs. 20.0%, respectively, OR 2.0; 95%CI 1.3–2.9, p = 0.0004). IPF patients with DRB1*1501 (n = 91) tended to have decreased diffusing capacities for carbon monoxide (DL_CO) compared to the 184 disease subjects who lacked this allele (37.8±1.7% vs. 42.8±1.4%, p = 0.036).

Conclusions/Significance

DRB1*1501 is more prevalent among IPF patients than normal subjects, and may be associated with greater impairment of gas exchange. These data are novel evidence that immunogenetic processes can play a role in the susceptibility to and/or manifestations of IPF. Findings here of a disease association at the HLA-DR locus have broad pathogenic implications, illustrate a specific chromosomal area for incremental, targeted genomic study, and may identify a distinct clinical phenotype among patients with this enigmatic, morbid lung disease.