Timothy Eley

Daclatasvir plus Sofosbuvir for Previously Treated or Untreated Chronic HCV Infection

BACKGROUND All-oral combination therapy is desirable for patients with chronic hepatitis C virus (HCV) infection. We evaluated daclatasvir (an HCV NS5A replication complex inhibitor) plus sofosbuvir (a nucleotide analogue HCV NS5B polymerase inhibitor) in patients infected with HCV genotype 1, 2, or 3. METHODS In this open-label study, we initially randomly assigned 44 previously untreated patients with HCV genotype 1 infection and 44 patients infected with HCV genotype 2 or 3 to daclatasvir at a dose of 60 mg orally once daily plus sofosbuvir at a dose of 400 mg orally once daily, with or without ribavirin, for 24 weeks. The study was expanded to include 123 additional patients with genotype 1 infection who were randomly assigned to daclatasvir plus sofosbuvir, with or without ribavirin, for 12 weeks (82 previously untreated patients) or 24 weeks (41 patients who had previous virologic failure with telaprevir or boceprevir plus peginterferon alfa-ribavirin). The primary end point was a sustained virologic response (an HCV RNA level of <25 IU per milliliter) at week 12 after the end of therapy. RESULTS Overall, 211 patients received treatment. Among patients with genotype 1 infection, 98% of 126 previously untreated patients and 98% of 41 patients who did not have a sustained virologic response with HCV protease inhibitors had a sustained virologic response at week 12 after the end of therapy. A total of 92% of 26 patients with genotype 2 infection and 89% of 18 patients with genotype 3 infection had a sustained virologic response at week 12. High rates of sustained virologic response at week 12 were observed among patients with HCV subtypes 1a and 1b (98% and 100%, respectively) and those with CC and non-CC IL28B genotypes (93% and 98%, respectively), as well as among patients who received ribavirin and those who did not (94% and 98%, respectively). The most common adverse events were fatigue, headache, and nausea. CONCLUSIONS Once-daily oral daclatasvir plus sofosbuvir was associated with high rates of sustained virologic response among patients infected with HCV genotype 1, 2, or 3, including patients with no response to prior therapy with telaprevir or boceprevir. (Funded by Bristol-Myers Squibb and Pharmasset (Gilead); A1444040 ClinicalTrials.gov number, NCT01359644.).

Preliminary Study of Two Antiviral Agents for Hepatitis C Genotype 1

BACKGROUND Patients with chronic hepatitis C virus (HCV) infection who have not had a response to therapy with peginterferon and ribavirin may benefit from the addition of multiple direct-acting antiviral agents to their treatment regimen. METHODS This open-label, phase 2a study included an exploratory cohort of 21 patients with chronic HCV genotype 1 infection who had not had a response to previous therapy (i.e., had not had ≥2 log(10) decline in HCV RNA after ≥12 weeks of treatment with peginterferon and ribavirin). We randomly assigned patients to receive the NS5A replication complex inhibitor daclatasvir (60 mg once daily) and the NS3 protease inhibitor asunaprevir (600 mg twice daily) alone (group A, 11 patients) or in combination with peginterferon alfa-2a and ribavirin (group B, 10 patients) for 24 weeks. The primary end point was the percentage of patients with a sustained virologic response 12 weeks after the end of the treatment period. RESULTS A total of 4 patients in group A (36%; 2 of 9 with HCV genotype 1a and 2 of 2 with genotype 1b) had a sustained virologic response at 12 weeks after treatment and also at 24 weeks after treatment.. Six patients (all with HCV genotype 1a) had viral breakthrough while receiving therapy, and resistance mutations to both antiviral agents were found in all cases; 1 patient had a viral response at the end of treatment but had a relapse after the treatment period. All 10 patients in group B had a sustained virologic response at 12 weeks after treatment, and 9 had a sustained virologic response at 24 weeks after treatment. Diarrhea was the most common adverse event in both groups. Six patients had transient elevations of alanine aminotransferase levels to more than 3 times the upper limit of the normal range. CONCLUSIONS This preliminary study involving patients with HCV genotype 1 infection who had not had a response to prior therapy showed that a sustained virologic response can be achieved with two direct-acting antiviral agents only. In addition, a high rate of sustained virologic response was achieved when the two direct-acting antiviral agents were combined with peginterferon alfa-2a and ribavirin. (Funded by Bristol-Myers Squibb; ClinicalTrials.gov number, NCT01012895.).

Daclatasvir Plus Asunaprevir for Chronic HCV Genotype 1b Infection

All‐oral combinations of direct‐acting antivirals may improve efficacy and safety outcomes for patients with hepatitis C virus (HCV) infection, particularly those who are poor candidates for current interferon/ribavirin‐based regimens. In this open‐label, phase 3 study, 135 interferon‐ineligible/intolerant and 87 nonresponder patients with chronic HCV genotype 1b infection were enrolled at 24 centers in Japan. Patients received daclatasvir 60 mg once daily plus asunaprevir 100 mg twice daily for 24 weeks. The primary endpoint was sustained virologic response 24 weeks after treatment (SVR24). This study is registered with ClinicalTrials.gov (NCT01497834). SVR24 was achieved by 87.4% of interferon‐ineligible/intolerant patients and 80.5% of nonresponder (null and partial) patients; rates were similar in cirrhosis (90.9%) and noncirrhosis (84.0%) patients, and in patients with IL28B CC (84.5%) or non‐CC (84.8%) genotypes. Fourteen patients in each group (12.6%) discontinued dual therapy, mainly due to adverse events or lack of efficacy. Nine nonresponder patients received additional treatment with peginterferon/ribavirin per protocol‐defined criteria. The rate of serious adverse events was low (5.9%) and varied among patients. The most common adverse events were nasopharyngitis, increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST), headache, diarrhea, and pyrexia. Conclusion: Interferon‐free, ribavirin‐free all‐oral therapy with daclatasvir and asunaprevir for 24 weeks is well tolerated and can achieve a high rate of SVR in patients with HCV genotype 1b who were ineligible, intolerant, or had not responded to prior interferon‐based therapy. (Hepatology 2014;59:2083–2091)

Dual oral therapy with daclatasvir and asunaprevir for patients with HCV genotype 1b infection and limited treatment options

BACKGROUND & AIMS Improved therapeutic options for chronic hepatitis C virus (HCV) infection are needed for patients who are poor candidates for treatment with current regimens due to anticipated intolerability or low likelihood of response. METHODS In this open-label, phase 2a study of Japanese patients with chronic HCV genotype 1b infection, 21 null responders (<2 log₁₀ HCV RNA reduction after 12 weeks of peginterferon/ribavirin) and 22 patients intolerant to or medically ineligible for peginterferon/ribavirin therapy received dual oral treatment for 24 weeks with the NS5A replication complex inhibitor daclatasvir (DCV) and the NS3 protease inhibitor asunaprevir (ASV). The primary efficacy end point was sustained virologic response at 12 weeks post-treatment (SVR₁₂). RESULTS Thirty-six of 43 enrolled patients completed 24 weeks of therapy. Serum HCV RNA levels declined rapidly, becoming undetectable in all patients on therapy by week 8. Overall, 76.7% of patients achieved SVR₁₂ and SVR₂₄, including 90.5% of null responders and 63.6% of ineligible/intolerant patients. There were no virologic failures among null responders. Three ineligible/intolerant patients experienced viral breakthrough and four relapsed post-treatment. Diarrhea, nasopharyngitis, headache, and ALT/AST increases, generally mild, were the most common adverse events; three discontinuations before week 24 were due to adverse events that included hyperbilirubinemia and transaminase elevations (two patients). CONCLUSIONS Dual therapy with daclatasvir and asunaprevir, without peginterferon/ribavirin, was well tolerated and achieved high SVR rates in two groups of difficult-to-treat patients with hepatitis C virus genotype 1b infection.

Efficacy of an Interferon- and Ribavirin-Free Regimen of Daclatasvir, Asunaprevir, and BMS-791325 in Treatment-Naive Patients With HCV Genotype 1 Infection

BACKGROUND & AIMS The combination of peginterferon and ribavirin with telaprevir or boceprevir is the standard treatment of hepatitis C virus (HCV) genotype 1 infection. However, these drugs are not well tolerated because of their side effects and suboptimal virologic responses. In a phase 2a, open-label study, we examined the safety and efficacy of an interferon-free, ribavirin-free regimen of direct-acting antivirals, comprising daclatasvir (an NS5A replication complex inhibitor), asunaprevir (an NS3 protease inhibitor), and BMS-791325 (a non-nucleoside NS5B inhibitor), in patients with chronic HCV infection. METHODS We analyzed data from 66 treatment-naive patients with HCV genotype 1 infection without cirrhosis who were assigned randomly to groups given daclatasvir (60 mg, once daily), asunaprevir (200 mg, twice daily), and BMS-791325 (75 or 150 mg, twice daily) for 12 or 24 weeks. The primary end point was an HCV-RNA level less than 25 IU/mL at 12 weeks after treatment (sustained virologic response at 12 weeks [SVR12]). RESULTS In 64 patients, HCV-RNA levels were less than 25 IU/mL by week 4 of treatment (including 48 of 49 patients with HCV genotype 1a infection and 45 of 46 patients with the non-CC interleukin 28B genotype). Sixty-one patients (92%) achieved SVR12, based on a modified intention-to-treat analysis. Virologic responses were similar between 12 and 24 weeks of treatment. During the study, 2 patients experienced viral breakthrough and 1 patient relapsed. There were no grade 3-4 increases in levels of alanine or aspartate aminotransferases or bilirubin; there were no deaths or discontinuations resulting from serious adverse events or adverse events related to the treatment regimen. The most common adverse events were headache, asthenia, and gastrointestinal symptoms. CONCLUSIONS In a phase 2a study, the all-oral, interferon-free, and ribavirin-free regimen of daclatasvir, asunaprevir, and BMS-791325 was well tolerated and achieved high rates of SVR12 in patients with HCV genotype 1 infection. Further studies of this regimen are warranted. ClinicalTrials.gov, number NCT01455090.

Randomized trial of daclatasvir and asunaprevir with or without PegIFN/RBV for hepatitis C virus genotype 1 null responders

BACKGROUND & AIMS Patients with chronic hepatitis C virus (HCV) infection and prior null response (<2 log HCV RNA decline after ⩾ 12 weeks of PegIFN/RBV) have limited options. We evaluated daclatasvir plus once- or twice-daily asunaprevir in non-cirrhotic genotype 1 null responders. METHODS In this randomized, phase 2a, open-label, 24-week treatment study, 101 patients received daclatasvir (60 mg) once-daily. In addition, 38 genotype 1b patients received asunaprevir (200mg) twice- (DUAL A1) or once-daily (DUAL A2); 36 genotype 1a and 5 genotype 1b patients received asunaprevir twice- (QUAD B1) or once-daily (QUAD B2) plus PegIFN/RBV; and 18 genotype 1a and 4 genotype 1b patients received asunaprevir twice-daily plus ribavirin (TRIPLE B3). The primary endpoint was undetectable HCV RNA 12 weeks post-treatment (sustained virologic response, SVR12). RESULTS Across all groups, mean HCV RNA was ⩾ 6 log IU/ml, and 99% of patients had a non-CC IL28B genotype. SVR12 rates were 78% (A1), 65% (A2), 95% (B1), and 95% (B2). In B3, most genotype 1a patients experienced virologic breakthrough. The most common adverse events were headache, diarrhea, and asthenia. Grade 3-4 aminotransferase elevations were infrequent and not treatment-limiting. CONCLUSIONS In genotype 1 null responders, daclatasvir plus twice-daily asunaprevir DUAL therapy is effective for most genotype 1b patients, and daclatasvir, asunaprevir, and PegIFN/RBV QUAD therapy is effective for nearly all genotype 1a and 1b patients; but neither DUAL nor TRIPLE therapy is effective for genotype 1a patients. Interferon-free regimens including daclatasvir and twice-daily asunaprevir for genotype 1 null responders should be tailored to subtype.

Resistance analysis of hepatitis C virus genotype 1 prior treatment null responders receiving daclatasvir and asunaprevir

In a sentinel cohort, hepatitis C virus (HCV) patients (primarily genotype [GT] 1a) were treated with daclatasvir (NS5A inhibitor) and asunaprevir (NS3 protease inhibitor). Preexistence, emergence, and persistence of resistance variants in patients who failed this treatment are described. HCV‐infected null responders received daclatasvir (60 mg once daily) and asunaprevir (600 mg twice daily) alone (Group A, 11 patients) or with peginterferon alfa‐2a and ribavirin (Group B, 10 patients) for 24 weeks. Resistance testing was performed on baseline samples and samples with HCV RNA ≥1,000 IU/mL at Week 1 through posttreatment Week 48. Resistance substitution susceptibility to inhibition by asunaprevir and daclatasvir was assessed using HCV replicon assays. In Group A, six GT1a patients experiencing viral breakthrough and one GT1a patient who relapsed had detectable NS5A (Q30E/R, L31V/M, Y93C/N) and NS3 (R155K, D168A/E/V/Y) resistance‐associated variants at failure. Two of six viral breakthrough patients achieved SVR48 after treatment intensification with peginterferon alfa‐2a and ribavirin. For 2/4 viral breakthrough patients not responding to treatment intensification, NS3 resistance variants changed (D168Y to D168T; R155K to V36M‐R155K). At posttreatment Week 48, daclatasvir‐resistant variants persisted while asunaprevir‐resistant variants were generally replaced by wild‐type sequences. The NS3 sequence remained unchanged in the one patient with NS3‐R155K at baseline, relapse, and posttreatment Week 48. In Group B, no viral breakthrough was observed. Conclusion: The treatment failure of daclatasvir and asunaprevir in HCV GT1a patients was associated with both NS5A and NS3 resistance variants in prior null responders. NS5A resistance variants persisted while NS3 resistance variants generally decayed, suggesting a higher relative fitness of NS5A variants. (Hepatology 2013;53:902–911)

Phase I Study of the Effect of Gastric Acid pH Modulators on the Bioavailability of Oral Dasatinib in Healthy Subjects

Dasatinib is a tyrosine kinase inhibitor (including BCR‐ABL and the SRC family) that is effective in patients with chronic myeloid leukemia. Dasatinib has pH‐dependent solubility and is bioavailable as an oral formulation. The effect of gastric pH modifiers on dasatinib pharmacokinetics is evaluated in an open‐label, randomized, 3‐period, 3‐treatment crossover study. Twenty‐four healthy subjects receive treatment A (2 doses of dasatinib 50 mg separated by 12 hours), treatment B (famotidine 40 mg given 2 hours after dasatinib 50 mg and 10 hours before another dose of dasatinib 50 mg), and treatment C (30 mL of an antacid containing aluminum/magnesium hydroxides given 2 hours before dasatinib 50 mg and concomitantly with dasatinib 50 mg 12 hours after the previous dasatinib dose); a 7‐day washout separates each treatment period. When famotidine is administered 2 hours after dasatinib, dasatinib exposure is similar to dasatinib administered alone. However, dasatinib exposure is reduced by ∼60% when famotidine is administered 10 hours before dasatinib dosing. In contrast, dasatinib exposure is unchanged when antacid (Maalox) is administered 2 hours before dasatinib; but when the antacid is coadministered with dasatinib, dasatinib exposure is reduced by ∼55% to 58%. This indicates that H2‐receptor antagonists should not be coadministered with dasatinib. Dasatinib may be administered with acid‐neutralizing antacids if the doses are temporally separated by at least 2 hours.

1356 QUADRUPLE THERAPY WITH BMS-790052, BMS-650032 AND PEG-IFN/RBV FOR 24 WEEKS RESULTS IN 100% SVR12 IN HCV GENOTYPE 1 NULL RESPONDERS

Background and Aims: The chemokine IP-10 (or CXCL10) has been identified to be a negative predictor for response to pegylated-interferon (peg-IFN)-a2/ribavirin (RBV) therapy. We have recently demonstrated that in the context of chronic HCV disease pathogenesis, IP-10 is cleaved by the enzyme dipeptidylpeptidase IV (DPP4 or CD26), converting it from an agonist into an antagonist (Casrouge et al, JCI 2011). We have now established an experimental model to evaluate the impact of DPP4 inhibition as a strategy for enhancing lymphocyte cell trafficking to the liver. Methods: We have conducted human subject studies and established small animal models to evaluate the impact of DPP4 inhibition of lymphocyte trafficking. We utilize novel assays capable of distinguishing the agonist and antagonist forms of human IP-10; clinically approved inhibitors; as well as genetic knock-out animals deficient in DPP4 to study the regulation of lymphocyte trafficking. Using patient data and infection models in mice we study T and NK cell trafficking to sites of inflammation, including the liver parenchyma.

Randomized study of asunaprevir plus pegylated interferon-α and ribavirin for previously untreated genotype 1 chronic hepatitis C

BACKGROUND Asunaprevir is a selective NS3 protease inhibitor with in vitro activity against HCV genotypes 1 and 4. METHODS In this Phase IIa double-blind study, treatment-naive HCV genotype-1-infected patients in the United States and France were randomly assigned 1:1:1:1 to placebo or asunaprevir 200 mg twice daily, 600 mg twice daily or 600 mg once daily in combination with pegylated interferon (PEG-IFN)-α2a and ribavirin for 48 weeks. The primary efficacy end point was undetectable HCV RNA at weeks 4 and 12 (extended rapid virological response [eRVR]). Other end points included safety and undetectable HCV RNA at 24 weeks post-treatment (24-week sustained virological response [SVR24]). RESULTS A total of 47 patients were randomized and treated. eRVR was achieved by 75% (9/12), 75% (9/12) and 92% (11/12) of patients in the asunaprevir 200 mg twice-daily, 600 mg twice-daily and 600 mg once-daily groups, respectively, versus 0% (0/11) in the placebo group. Corresponding SVR24 rates were 83% (10/12), 83% (10/12) and 92% (11/12) in the asunaprevir groups and 46% (5/11) in the placebo group. There was no virological breakthrough in any asunaprevir group. Following the 12-week analysis, the 600 mg doses were reduced to 200 mg twice daily because of a greater frequency of transaminase elevations at the 600 mg dose. The most common grade 3-4 laboratory abnormalities were consistent with those reported for PEG-IFN and ribavirin. CONCLUSIONS Asunaprevir plus PEG-IFN and ribavirin achieved higher response rates than placebo plus PEG-IFN and ribavirin, with a tolerable adverse event profile at the 200 mg twice-daily dose. This dose is being evaluated in the Phase IIb and Phase III studies.