Effect of abacavir on sustained virologic response to HCV treatment in HIV/HCV co-infected patients, Cohere in Eurocoord

BACKGROUND

Contradicting results on the effect of abacavir (ABC) on hepatitis C virus (HCV) treatment responses in HIV/HCV co-infected patients have been reported. We evaluated the influence of ABC on the response to pegylated interferon (pegIFN) and ribavirin (RBV)-containing HCV treatment in HIV/HCV co-infected patients in a large European cohort collaboration, including data from different European countries.

METHODS

HIV/HCV co-infected patients were included if they were aged ≥16 years, received pegIFN alfa-2a or 2b and RBV combination treatment and were enrolled in the COHERE cohort collaboration. Logistic regression was used to evaluate the impact of abacavir on achieving a sustained virologic response (SVR) to HCV treatment.

RESULTS

In total 1309 HIV/HCV co-infected patients who had received HCV therapy were included, of whom 490 (37 %) had achieved an SVR. No statistically significant difference was seen for patients using ABC-containing regimens compared to patients using an emtricitabine + tenofovir (FTC + TDF)-containing backbone, which was the most frequently used backbone. In the multivariate analyses, patients using a protease inhibitor (PI)-boosted regimen were less likely to achieve an SVR compared to patients using a non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based regimen (OR: 0.61, 95 % CI: 0.41-0.91). The backbone combinations zidovudine&lamivudine (AZT + 3TC) and stavudine&lamivudine (d4t + 3TC) were associated with lower SRV rates (0.45 (0.24-0.82) and 0.46 (0.22-0.96), respectively).

CONCLUSION

The results of this large European cohort study validate that SVR rates are generally not affected by ABC. Use of d4T or AZT as part of the HIV treatment regimen was associated with a lower likelihood of achieving an SVR.

Safety, tolerability, and pharmacokinetics of ribavirin in hepatitis C virus-infected patients with various degrees of renal impairment

Ribavirin (RBV) is an integral part of standard-of-care hepatitis C virus (HCV) treatments and many future regimens under investigation. The pharmacokinetics (PK), safety, and tolerability of RBV in chronically HCV-infected patients with renal impairment are not well defined and were the focus of an open-label PK study in HCV-infected patients receiving RBV plus pegylated interferon. Serial RBV plasma samples were collected over 12 h on day 1 of weeks 1 and 12 from patients with moderate renal impairment (creatinine clearance [CLCR], 30 to 50 ml/min; RBV, 600 mg daily), severe renal impairment (CLCR, <30 ml/min; RBV, 400 mg daily), end-stage renal disease (ESRD) (RBV, 200 mg daily), or normal renal function (CLCR, >80 ml/min; RBV, 800 to 1,200 mg daily). Of the 44 patients, 9 had moderately impaired renal function, 10 had severely impaired renal function, 13 had ESRD, and 12 had normal renal function. The RBV dose was reduced because of adverse events (AEs) in 71% and 53% of severe and moderate renal impairment groups, respectively. Despite this modification, patients with moderate and severe impairment had 12-hour (area under the concentration-time curve from 0 to 12 h [AUC0-12]) values 36% (38,452 ng · h/ml) and 25% (35,101 ng · h/ml) higher, respectively, than those with normal renal function (28,192 ng · h/ml). Patients with ESRD tolerated a 200-mg daily dose, and AUC0-12 was 20% lower (22,629 ng · h/ml) than in patients with normal renal function. PK modeling and simulation (M&S) indicated that doses of 200 mg or 400 mg alternating daily for patients with moderate renal impairment and 200 mg daily for patients with severe renal impairment were the most appropriate dose regimens in these patients.

The association of cytopenias and weight loss with hepatitis C virus virologic response in HIV/HCV-coinfected patients treated with PEG-IFN and RBV

BACKGROUND

Pegylated interferon (PEG-IFN)/ribavirin (RBV)-related cytopenias have been associated with improved virological outcomes among hepatitis C virus (HCV)-monoinfected patients. This analysis evaluated PEG-IFN/RBV-related cytopenias with virological responses among HIV/HCV-coinfected patients.

METHODS

Pooled data from PARADIGM and AIDS Pegasys Ribavirin International CO-infection Trial (APRICOT) trials of HIV/HCV-infected patients treated with PEG-IFN/RBV. Virologic response was categorized as HCV RNA detectable (end of treatment nonresponders [ET-NR]) or nondetectable (end of treatment responders [ETR]). Declines in hemoglobin (Hgb), platelets, neutrophils, lymphocytes, and weight between the groups were compared via analysis of covariance and Cochran-Mantel-Haenszel test.

RESULTS

A total of 474 patients, 291 ET-NR and 183 ETR (67 relapsers, 116 with sustained virologic response), 81% male, 52% Caucasian, 88% noncirrhotic, and 67% nondetectable HIV. The ETR experienced greater Hgb declines (≥3.0 g/dL) from baseline (73.8% versus 55.0%; P < .0001), neutrophils ≤1 and ≤ 0.5 × 10(9)/L (66.1% versus 56.4%; P = .0334 and 42.6% versus 33.3%; P = .0312, respectively), and lymphocytes ≤1.5 and ≤0.5 × 10(9)/L (99.5% versus 87.6%; P < .0001 and 24.6% versus 14.9%; P =.0079, respectively).

CONCLUSIONS

The HIV/HCV-coinfected patients with ETR experienced greater declines in Hgb, neutrophils, and lymphocytes than the ET-NR patients.