Albinterferon Alfa-2b was not inferior to pegylated interferon-α in a randomized trial of patients with chronic hepatitis C virus genotype 2 or 3

Ropeginterferon alfa-2b in patients with genotype 1 chronic hepatitis C: Pharmacokinetics, safety, and preliminary efficacy

Background and Aim

Ropeginterferon alfa‐2b (P1101) is a novel long‐acting mono‐PEGylated recombinant proline interferon (IFN) conjugated to a 40 kDa branched polyethylene glycol (PEG) chain at its N‐terminus, allowing every‐two‐week injection. It received European Medicines Agency and Taiwan marketing authorization for the treatment of polycythemia vera in 2019 and 2020, respectively. This phase 2 study aimed to evaluate the pharmacokinetics, safety, and preliminary efficacy of ropeginterferon alfa‐2b as compared with PEG‐IFN‐α2a in patients with chronic hepatitis C virus genotype 1 infection.

Methods

One hundred six treatment naive patients were enrolled in this phase 2 study and randomized to four treatment groups: subcutaneous weekly PEG‐IFN‐α2a 180 μg (group 1), weekly ropeginterferon alfa‐2b 180 μg (group 2), weekly ropeginterferon alfa‐2b 270 μg (group 3), or biweekly ropeginterferon alfa‐2b 450 μg (group 4) plus ribavirin for 48 weeks.

Results

After multiple weekly administration, serum exposure (AUC_0‐τ) in ropeginterferon alfa‐2b 180 μg was approximately 41% greater and the accumulation ratio of 2‐fold greater than PEG‐IFN‐α2a 180 μg. The incidences of flu‐like symptoms were 66.7% (18/27), 53.3% (16/30), 55.0% (11/20), and 48.3% (14/29), anxiety were 14.8% (4/27), 6.7% (2/30), 0%, and 0%, and depression were 25.9% (7/27), 13.3% (4/30), 0%, and 3.4% (1/29), for groups 1–4, respectively. Two grade 2 of 3 depression were noted in PEG‐IFN‐α2a arm, but none in ropeginterferon arms. The SVR24 rates were 77.8% (21/27), 66.7% (20/30), 80% (16/20), and 69% (20/29), respectively.

Conclusions

Ropeginterferon alfa‐2b showed longer effective half‐life and superior safety profile than PEG‐IFN‐α2a. Biweekly injection of ropeginterferon alfa‐2b will be studied in larger viral hepatitis patient population.

Ropeginterferon alfa-2b every 2 weeks as a novel pegylated interferon for patients with chronic hepatitis B

Background

Ropeginterferon alfa-2b is a novel mono-pegylated interferon that has only one major form as opposed to 8–14 isomers of other on-market pegylated interferon, allowing injection every two or more weeks with higher tolerability. It received European Medicines Agency and Taiwan marketing authorization in 2019 and 2020, for treatment of polycythemia vera. This phase I/II study aimed to have preliminary evaluation of safety and efficacy in chronic hepatitis B.

Methods

Thirty-one HBeAg-positive and 31 HBeAg-negative were stratified by HBeAg status and randomized at 1:1:1 ratio to q2w ropeginterferon alfa-2b 350 μg (group 1), q2w 450 μg (group 2) or q1w PEG-IFN alfa-2a 180 μg (group 3). Each patient received 48-week treatment (TW48) and 24-week post-treatment follow-up (FW24).

Results

The baseline demographics were comparable among the three groups, except for mean HBeAg in HBeAg-positive patients (2.90, 2.23, 2.99 log₁₀ S/CO, respectively). Cumulative HBeAg seroconversion rate at follow-up period was 27.3% (3/11), 36.4% (4/11), and 11.1% (1/9) with time to HBeAg seroconversion starting from TW24, TW16, and TW48 in group 1, 2, and 3, respectively. The rate of HBV DNA < 2000 IU/mL and HBsAg levels < 1500 IU/mL at FW24 were comparable in all groups. Ropeginterferon alfa-2b (group 1 & 2) had numerically lower incidence of rash (9.5% and 4.5%) as compared to PEG-IFN alfa-2a (36.8%). Ropeginterferon alfa-2b 350 μg (group 1) had more ALT elevation (38.1%), however the rate was comparable in group 2 (9.1%) and group 3 (10.5%).

Conclusion

In this preliminary study, ropeginterferon alfa-2b, although in only half the number of injections, is as safe and effective as pegylated interferon alfa-2a for chronic hepatitis B.

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s12072-020-10098-y) contains supplementary material, which is available to authorized users.

Ropeginterferon Alfa-2b administered every two weeks for patients with genotype 2 chronic hepatitis C

BACKGROUND

Ropeginterferon alfa-2b is a novel mono-pegylated interferon that has only one major form as opposed to the 8 to 14 isomers of other on-market pegylated interferon products, allowing every-two-week injection with high tolerability. It received European Medicines Agency marketing authorization in 2019 and Taiwan Biologics License Applications Approval in 2020 for the treatment of polycythemia vera. This study aimed to evaluate the safety and efficacy of Ropeginterferon alfa-2b plus ribavirin in genotype 2 chronic hepatitis C (CHC) patients.

METHODS

Eighty-six treatment naive patients with genotype 2 CHC were randomized to weekly peginterferon alfa-2a (Peg-IFN-α2a) at 180 μg (n = 22), or every-two-week Ropeginterferon alfa-2b at 270 μg (n = 23), 360 μg (n = 21), 450 μg (n = 20), plus daily oral ribavirin 1000 mg (≤75 kg) or 1200 mg (>75 kg). Patients with rapid virologic response received 16-week regimen while those without RVR received 24-week regimen. The primary endpoint was sustained virologic response at 24 weeks post-treatment (SVR24).

RESULTS

SVR24 was achieved by 95.5%, 78.3%, 85.7%, and 60% of subjects in Peg-IFN-α2a 180 μg, Ropeginterferon alfa-2b 270 μg, 360 μg, and 450 μg groups, respectively. The safety profile was similar across 4 groups. The incidence rate of adverse event during the treatment period was 0.407, 0.252, 0.395, and 0.347 per patient-week, respectively.

CONCLUSION

Ropeginterferon alfa-2b, although at only half the number of injections, is as safe and effective as Peg-IFN-α2a for genotype 2 CHC. A phase 3 study to confirm safety and efficacy of Ropeginterferon alfa-2b in genotype 2 CHC is ongoing.

AlbuCORE: an albumin-based molecular scaffold for multivalent biologics design

As biologics have become a mainstay in the development of novel therapies, protein engineering tools to expand on their structural advantages, namely specificity, affinity, and valency are of interest. Antibodies have dominated this field as the preferred scaffold for biologics development while there has been limited exploration into the use of albumin with its unique physiological characteristics as a platform for biologics design. There has been a great deal of interest to create bispecific and more complex multivalent molecules to build on the advantages offered by protein-based therapeutics relative to small molecules. Here, we explore the use of human serum albumin (HSA) as a scaffold for the design of multispecific biologics. In particular, we describe a structure-guided approach to the design of split HSA molecules we refer to as AlbuCORE, that effectively and spontaneously forms a native albumin-like molecule, but in a heterodimeric state upon co-expression. We show that the split AlbuCORE designs allow the creation of novel fusion entities with unique alternate geometries. We also show that, apart from these AlbuCORE fusion entities, there is an opportunity to explore their albumin-like small hydrophobic molecule carrying capacity as a drug conjugate in these designs.

One-month zero-order sustained release and tumor eradication after a single subcutaneous injection of interferon alpha fused with a body-temperature-responsive polypeptide

Upon a single subcutaneous injection, IFN-ELP in situ forms a depot, leading to one-month sustained release and dramatically enhanced tumor therapy.

DOES INSULIN RESISTANCE IMPAIR THE VIROLOGICAL RESPONSE TO PEGINTERFERON/RIBAVIRIN IN CHRONIC HEPATITIS C GENOTYPE 3 PATIENTS?

BACKGROUND

Insulin resistance and diabetes mellitus are common extrahepatic manifestations of chronic hepatitis C (HCV). Insulin resistance assessed by HOMA-IR is associated with low rates of sustained virological response, especially in HCV genotype 1 positive patients treated with peginterferon/ribavirin. The effect of insulin resistance on sustained virologic response in HCV genotype 3 positive patients who were treated with peginterferon/ribavirin still remains unclear.

OBJECTIVE

To evaluate the impact of insulin resistance on sustained virological response in HCV genotype 3 patients treated with peginterferon/ribavirin.

METHODS

A retrospective multicenter study was performed to evaluate the impact of insulin resistance on sustained virological response in non-diabetic HCV genotype 3 positive patients treated with peginterferon and ribavirin. A total of 200 HCV genotype 3 positive patients were enrolled in the study. All patients were non-diabetic. Each patient had a HOMA-IR value measured before the initiation of HCV treatment with peginterferon/ribavirin. The treatment duration was at least 24 weeks. The HOMA-IR cut-off was defined in the study as ≥2.5 due to the coefficient of correlation with sustained virological response of 0.202 (P=0.004).

RESULTS

Univariate analysis showed that age, aspartate aminotransferase, platelets, stage of fibrosis and HOMA-IR were predictors of sustained virological response. However multivariate analysis showed advanced fibrosis [OR=2.01 (95%CI: 0.986-4.119) P=0.05] and age [OR=1.06 (95%CI: 1.022-1.110) P=0.002] as negative predictors of sustained virological response.

CONCLUSION

In this retrospective multicenter study of non-diabetic HCV genotype 3 positive patients, insulin resistance was not associated with the sustained virological response in patients who were treated with peginterferon/ribavirin.

Antibody-targeted paclitaxel loaded nanoparticles for the treatment of CD20+ B-cell lymphoma

We developed a nano-antibody targeted chemotherapy (nATC) delivery strategy in which tumor specific and clinically relevant antibodies (rituximab, anti-CD20) are non-covalently bound to the albumin scaffold of nab-paclitaxel (ABX). We define the nanoparticle formed when the 2 drugs are bound (AR160). The newly created nATC retains the cytotoxicity of ABX and CD20 affinity of rituximab in vitro. We describe the binding characteristics of the ABX and rituximab in AR160 using peptide mapping/Biacore approach. Flow-based methods, including ImageStream and nanoparticle tracking, were used to characterize the AR160 particles in vitro. A mouse model of human B-cell lymphoma was utilized to test in vivo efficacy of AR160 therapy, which suggested improved tumor targeting (biodistribution) as the most likely mechanism of AR160 therapeutic superiority over ABX or rituximab alone. These data suggest a novel platform for nATC delivery using a slight modification of existing cancer drugs with significantly improved treatment efficacy.

Tolerability, pharmacokinetics and antiviral activity of rHSA/IFNα2a for the treatment of chronic hepatitis B infection

AIMS

A recombinant human serum albumin-interferon alpha2a fusion protein (rHSA/IFNα2a) is expected to extend the half-life of IFNα2a. This study aims to evaluate the tolerability, safety and efficacy of rHSA/IFNα2a.

METHODS

This is an open, randomized, positive control, multiple-dose ascending Phase Ib study. A panel of 32 treatment naïve and non-cirrhotic chronic hepatitis B patients were divided into four cohorts, and each received 600, 750 or 900 μg of rHSA/IFNα2a or 180 μg of PEG-IFNα2a for 3 months. Tolerability, pharmacokinetics and antiviral responses were assessed.

RESULTS

Thirty-one of 32 enrolled patients completed the treatment study. The rHSA/IFNα2a treatment was better tolerated than the PEG-IFNα2a 180 μg treatment, as evidenced by blood cell counts and higher serum albumin levels. Half-life (t_1/2 ) of rHSA/IFNα2a was estimated to be 120-140 h, and is potentially suitable for a dosing interval of 2 weeks or longer. Pharmacokinetics of the last dose between rHSA/IFNα2a 750 μg and PEG-IFNα2a 180 μg, with the exception of t_1/2 , was comparable, and a similar kinetics of inhibiting HBV DNA replication was observed in both groups. Mean reductions in serum HBV DNA levels after treatment were -1.32, -2.13, -1.10 and -2.48 log10 IU/ml in the 600, 750 and 900 μg rHSA/IFNα2a groups and PEG-IFNα2a group, respectively.

CONCLUSIONS

The rHSA/IFNα2a treatment was well tolerated and can be administered biweekly. Similar efficacy in inhibiting HBV replication was observed in both PEG-IFNα2a and rHSA/IFNα2a 750 μg groups.

A meta-analysis platform methodology for determining the comparative effectiveness of antihepatitis C virus regimens

AIM

Many hepatitis C virus regimens are unlikely to be compared head to head. In more difficult to treat populations where there is no standard of care, trials are single arm. We describe a flexible meta-analysis platform in this setting.

METHODS

Our meta-analysis is literature based. We illustrate our methodology and show how inference can be extended to single-arm trials.

RESULTS

As an example, in the single arm setting, a regimen with response rates of 84, 72 and 54% in genotype 1a across treatment naive, previous partial responders and previous null responders, respectively, would have 95% probability of superiority to IFN-α + RBV + TPV.

CONCLUSION

This is a rigorous approach to comparative effectiveness that accounts for varying patient populations and plans for the incorporation of emerging treatments.

Enhancing Pharmacokinetics, Tumor Accumulation, and Antitumor Efficacy by Elastin-Like Polypeptide Fusion of Interferon Alpha

Genetic fusion of elastin-like polypeptide (ELP) to the C-terminus of interferon alpha (IFN) generates a well-defined IFN-ELP fusion protein with high yield and well-retained bioactivity. The fusion protein significantly enhances pharmacokinetics, tumor accumulation, and antitumor efficacy of interferon alpha in a murine cancer model.

Potential Use of Biological Proteins for Liver Failure Therapy

Biological proteins have unlimited potential for use as pharmaceutical products due to their various biological activities, which include non-toxicity, biocompatibility, and biodegradability. Recent scientific advances allow for the development of novel innovative protein-based products that draw on the quality of their innate biological activities. Some of them hold promising potential for novel therapeutic agents/devices for addressing hepatic diseases such as hepatitis, fibrosis, and hepatocarcinomas. This review attempts to provide an overview of the development of protein-based products that take advantage of their biological activity for medication, and discusses possibilities for the therapeutic potential of protein-based products produced through different approaches to specifically target the liver (or hepatic cells: hepatocytes, hepatic stellate cells, liver sinusoidal endothelial cells, and Kupffer cells) in the treatment of hepatic diseases.

Immune-modulators to combat hepatitis B virus infection: From IFN-α to novel investigational immunotherapeutic strategies

Chronic hepatitis B virus (HBV) infection remains a major challenge for clinicians, as there are only two types of approved therapies: interferon-alpha (IFN-α) or its pegylated form, Peg-IFN-α and nucleoside analogs (e.g. tenofovir, entecavir...). The first are used as finite-duration treatments of around 48-52 weeks, while the second must be taken life-long to prevent rebound. Other immune-modulators, including other types of recombinant IFNs and cytokines/chemokines, could be developed for treating chronic hepatitis B. Alternatively, strategies aimed either at restoring or favoring the endogenous production of IFNs, cytokines and/or chemokines, or at alleviating HBV-mediated inhibitory processes could also be envisaged. In this article, we review current investigational, preclinical and clinical efforts to implement immune-modulatory components in the therapy of chronic hepatitis B. This review forms part of a symposium in Antiviral Research on "An unfinished story: from the discovery of the Australia antigen to the development of new curative therapies for hepatitis B".

Fusion Proteins for Half-Life Extension of Biologics as a Strategy to Make Biobetters

The purpose of making a "biobetter" biologic is to improve on the salient characteristics of a known biologic for which there is, minimally, clinical proof of concept or, maximally, marketed product data. There already are several examples in which second-generation or biobetter biologics have been generated by improving the pharmacokinetic properties of an innovative drug, including Neulasta(®) [a PEGylated, longer-half-life version of Neupogen(®) (filgrastim)] and Aranesp(®) [a longer-half-life version of Epogen(®) (epoetin-α)]. This review describes the use of protein fusion technologies such as Fc fusion proteins, fusion to human serum albumin, fusion to carboxy-terminal peptide, and other polypeptide fusion approaches to make biobetter drugs with more desirable pharmacokinetic profiles.

Alternative interferons and immunomodulators in the treatment of hepatitis C

Interferon-α (IFN-α) has been the mainstay of therapy for hepatitis C and is currently being combined with other drugs to improve the response rate. Newer therapeutic regimens are being developed to spare the use of IFN because of the important side effects associated with IFN-based therapy. However, there may still be a need for the use of IFN in certain populations. In addition, agents that mimic the actions of IFN but with fewer side effects may still be of major value. This review focuses on the development of alternative and new forms of IFNs and other immunomodulatory agents that may supplant IFN-α in combination therapy for hepatitis C.

Comparative efficacy, pharmacokinetic, pharmacodynamic activity, and interferon stimulated gene expression of different interferon formulations in HIV/HCV genotype-1 infected patients

The effect of different formulations of interferon on therapeutic response in patients coinfected with HIV and HCV is unclear. In this study, the safety, tolerability, viral kinetics (VK) modeling and host responses among HIV/HCV coinfected patients treated with pegylated-IFN or albinterferon alfa-2b (AlbIFN) with weight-based ribavirin were compared. Three trials treated 57 HIV/HCV coinfected genotype-1 patients with PegIFN alfa-2b (1.5 µg/kg/week) (n = 30), PegIFN alfa-2a (180 µg/week) (n = 10), and AlbIFN (900 µg/q2week) (n = 17) in combination with weight-based ribavirin (RBV). HCV RNA, safety labs, and interferon stimulated gene expression (ISG) was evaluated. Adverse events were documented at all study visits. HCV viral kinetics using a full pharmacokinetic/pharmacodynamic model was also evaluated. Baseline patient characteristics were similar across the three studies. All three formulations exhibited comparable safety and tolerability profiles and efficacy. VK/PK/PD parameters for all three studies as measured by mean efficiency and rate of infected cell loss were similar between the three groups. Host responses (ISG expression and immune activation markers) were similar among the three groups. All three regimens induced significant ISG at week 4 (P < 0.05) and ISG expression strongly correlated with therapeutic response (r = 0.65; P < 0.01). In summary, a comprehensive analysis of responses to three different interferon formulations in HIV/HCV coinfected patients demonstrated similar effects. Notably, interferon-based therapy results in a blunted host response followed by modest antiviral effect in HIV/HCV coinfected patients. This suggests that future treatment options that do not rely on host immune responses such as direct antiviral agents would be particularly beneficial in these difficult to treat patients.

Antiviral treatment of hepatitis C virus infection and factors affecting efficacy

Hepatitis C virus (HCV) infection is the leading cause of chronic liver-related diseases, including cirrhosis, liver failure, and hepatocellular carcinoma. Currently, no effective vaccine is available for HCV infection. Polyethylene glycol interferon-α (PegIFN-α) in combination with ribavirin (RBV) is the standard of care (SOC) for chronic hepatitis C. However, the efficacy of PegIFN-α and RBV combination therapy is less than 50% for genotype 1 HCV, which is the dominant virus in humans. In addition, IFN and RBV have several severe side effects. Therefore, strategies to improve sustained virological response (SVR) rates have been an important focus for clinical physicians. The serine protease inhibitors telaprevir and boceprevir were approved by the United States Food and Drug Administration in 2011. The addition of HCV protease inhibitors to the SOC has significantly improved the efficacy of treatments for HCV infection. Several direct-acting antiviral drugs currently in late-stage clinical trials, both with and without peg-IFN and RBV, have several advantages over the previous SOC, including higher specificity and efficacy, fewer side effects, and the ability to be administered orally, and might be optimal regimens in the future. Factors affecting the efficacy of anti-HCV treatments based on IFN-α include the HCV genotype, baseline viral load, virological response during treatment, host IL28B gene polymorphisms and hepatic steatosis. However, determining the effect of the above factors on DAA therapy is necessary. In this review, we summarize the development of anti-HCV agents and assess the main factors affecting the efficacy of antiviral treatments.

Patterns of interferon-alpha-induced thyroid dysfunction vary with ethnicity, sex, smoking status, and pretreatment thyrotropin in an international cohort of patients treated for hepatitis C

BACKGROUND

Interferon-alpha (IFNα)-induced thyroid dysfunction occurs in up to 20% of patients undergoing therapy for hepatitis C. The diversity of thyroid disease presentations suggests that several different pathological mechanisms are involved, such as autoimmunity and direct toxicity. Elucidating the relationships between risk factors and disease phenotype provides insight into the mechanisms of disease pathophysiology.

METHODS

We studied 869 euthyroid patients from the ACHIEVE 2/3 trial, a randomized international clinical trial comparing pegylated-IFNα2a weekly or albumin-IFNα2b every 2 weeks for up to 24 weeks in patients with hepatitis C, genotype 2 or 3, from 136 centers. The study population was 60% male and 55% white. Serum thyrotropin (TSH) and free thyroxine were measured before therapy, monthly during treatment from week 8, and at 4- and 12-week follow-up visits.

RESULTS

Overall, 181 (20.8%) participants had at least one abnormal TSH during the study. Low TSH occurred in 71 (8.2%), of whom 30 (3.5%) had a suppressed TSH below 0.1 mU/L. Hypothyroidism occurred in 53 patients (6.1%), with peak TSH above 10 mU/L in 12 patients (1.4%). Fifty-seven patients had a biphasic thyroiditis (6.6%), with extreme values for the nadir and/or peak TSH in all but one. Medical therapy was given to one thyrotoxic patient, four hypothyroid patients, and 26 biphasic thyroiditis patients. Multivariate logistic regression analysis demonstrated that biphasic thyroiditis is associated with being female and higher pretreatment serum TSH, whereas being Asian or a current smoker decreased the risk of thyroiditis. Hypo- and hyperthyroidism are most strongly predicted by the pretreatment TSH.

CONCLUSIONS

Biphasic thyroiditis accounted for the majority (58%) of clinically relevant IFNα-induced thyroid dysfunction. We confirmed our recent findings in a related cohort that female sex is a risk factor for thyroiditis but not hypothyroidism. Further, in this large multiethnic study, the risk of thyroiditis is dramatically increased, specifically for white women. Smoking was found to be protective of thyroiditis. These results support closer monitoring of women and those with a serum TSH at the extremes of the normal range during therapy so that prompt intervention can mitigate the consequences of thyroid dysfunction associated with IFNα treatment.

The impact of timing and prioritization on the cost-effectiveness of birth cohort testing and treatment for hepatitis C virus in the United States

Recent United States guidelines recommend one-time birth cohort testing for hepatitis C infection in persons born between 1945 and 1965; this represents a major public health policy undertaking. The purpose of this study was to assess the role of treatment timing and prioritization on predicted cost-effectiveness. The MONARCH hepatitis C lifetime simulation model was used in conjunction with a testing and treatment decision tree to estimate the cost-effectiveness of birth cohort versus risk-based testing incorporating information on age, fibrosis stage and treatment timing. The study used a 1945-1965 birth cohort and included disease progression, testing and treatment-related parameters. Scenario analysis was used to evaluate the impact of hepatitis C virus (HCV) prevalence, treatment eligibility, age, fibrosis stage and timing of treatment initiation on total costs, quality-adjusted life years (QALYs), HCV-related complications and cost-effectiveness. The cost-effectiveness of birth cohort versus risk-based testing was $28,602. Assuming 91% of the population is tested, at least 278,000 people need to be treated for birth cohort testing to maintain cost-effectiveness. Prioritizing treatment toward those with more advanced fibrosis is associated with a decrease in total cost of $7.5 billion and 59,035 fewer HCV-related complications. Total QALYs and complications avoided are maximized when treatment initiation occurs as soon as possible after testing.

CONCLUSION

This study confirms that birth cohort testing is, on average, cost-effective. However, this remains true only when enough tested and HCV-positive subjects are treated to generate sufficient cost offsets and QALY gains. Given the practical and financial challenges associated with implementing birth cohort testing, the greatest return on investment is obtained when eligible patients are treated immediately and those with more advanced disease are prioritized.

Decline in pulmonary function during chronic hepatitis C virus therapy with modified interferon alfa and ribavirin

Rare interstitial lung disease cases have been reported with albinterferon alfa-2b (albIFN) and pegylated interferon alfa-2a (Peg-IFNα-2a) in chronic hepatitis C virus (HCV) patients. Systematic pulmonary function evaluation was conducted in a study of albIFN q4wk vs Peg-IFNα-2a qwk in patients with chronic HCV genotypes 2/3. Three hundred and ninety-one patients were randomly assigned 4:4:4:3 to one of four, open-label, 24-week treatment groups including oral ribavirin 800 mg/d: albIFN 900/1200/1500 μg q4wk or Peg-IFNα-2a 180 μg qwk. Standardized spirometry and diffusing capacity of the lung for carbon monoxide (DLCO) were recorded at baseline, weeks 12 and 24, and 6 months posttreatment, and chest X-rays (CXRs) at baseline and week 24. Baseline spirometry and DLCO were abnormal in 35 (13%) and 98 (26%) patients, respectively. Baseline interstitial CXR findings were rare (4 [1%]). During the study, clinically relevant DLCO declines (≥15%) were observed in 173 patients (48%), and were more frequent with Peg-IFNα-2a and albIFN 1500 μg; 24 weeks posttreatment, 57 patients (18%) still had significantly decreased DLCO, with a pattern for greater rates with albIFN vs Peg-IFNα-2a. One patient developed new interstitial CXR abnormalities, but there were no clinically relevant interstitial lung disease cases. The risk of persistent posttreatment DLCO decrease was not related to smoking, alcohol, HCV genotype, sustained virologic response, or baseline viral load or spirometry. Clinically relevant DLCO declines occurred frequently in chronic HCV patients receiving IFNα/ribavirin therapy and commonly persisted for ≥6 months posttherapy. The underlying mechanism and clinical implications for long-term pulmonary function impairment warrant further research.

IFN-α subtypes: distinct biological activities in anti-viral therapy

During most viral infections, the immediate host response is characterized by an induction of type I IFN. These cytokines have various biological activities, including anti-viral, anti-proliferative and immunomodulatory effects. After induction, they bind to their IFN-α/β receptor, which leads to downstream signalling resulting in the expression of numerous different IFN-stimulated genes. These genes encode anti-viral proteins that directly inhibit viral replication as well as modulate immune function. Thus, the induction of type I IFN is a very powerful tool for the host to fight virus infections. Many viruses evade this response by various strategies like the direct suppression of IFN induction or inhibition of the IFN signalling pathway. Therefore, the therapeutic application of exogenous type I IFN or molecules that induce strong IFN responses should be of great potential for future immunotherapies against viral infections. Type I IFN is currently used as a treatment in chronic hepatitis B and C virus infection, but as yet is not widely utilized for other viral infections. One reason for this restricted clinical use is that type I IFN belongs to a multigene family that includes 13 different IFN-α subtypes and IFN-β, whose individual anti-viral and immunomodulatory properties have so far not been investigated in detail to improve IFN therapy against viral infections in humans. In this review, we summarize the recent achievements in defining the distinct biological functions of type I IFN subtypes in cell culture and in animal models of viral infection as well as their clinical usage in chronic hepatitis virus infections.

Randomized trial of albinterferon alfa-2b every 4 weeks for chronic hepatitis C virus genotype 2/3

Albinterferon alfa-2b (albIFN) is a fusion protein of recombinant human albumin/recombinant interferon (IFN)-α-2b, with ∼200-h half-life. Safety/efficacy of albIFN q4wk was evaluated in 391 treatment-naive patients with chronic hepatitis C virus (HCV) genotype 2/3. Patients were randomized 3:4:4:4 to one of four open-label treatment groups: pegylated IFN (Peg-IFN)-α-2a 180 μg qwk or albIFN 900, 1200 or 1500 μg q4wk, plus oral ribavirin 800 mg/day, for 24 weeks. Primary efficacy endpoint was sustained virologic response (SVR; HCV RNA <20 IU/mL 24 weeks post-treatment). SVR rates were as follows: 85%, 76%, 76% and 78% with Peg-IFNα-2a and albIFN 900, 1200 and 1500 μg, respectively (P = NS); corresponding rapid virologic response rates (HCV RNA <43 IU/mL at week 4) were as follows: 78%, 49% (P < 0.001), 60% (P = 0.01) and 71%. SVR rates were not influenced by interleukin 28B genotype, although rapid virologic response rates were greater with interleukin 28B CC (P = NS). Serious adverse event rates were as follows: 4%, 11%, 3% and 3% with Peg-IFNα-2a and albIFN 900, 1200 and 1500 μg, respectively. No increase in serious/severe respiratory events was noted with albIFN. Fewer absolute neutrophil count reductions <750/mm(3) occurred with albIFN (P = 0.03), leading to fewer IFN dose reductions. Haemoglobin reductions <10 g/dL were less frequent with albIFN 900 and 1200 μg vs 1500 μg and Peg-IFNα-2a (P = 0.02), leading to fewer ribavirin dose reductions. albIFN administered q4wk produced fewer haematologic reductions than Peg-IFNα-2a, but had numerically lower SVR rates (P = NS) in patients with chronic HCV genotype 2/3.

New Antiviral Therapies in the Management of HCV Infection

Improved knowledge of the HCV life cycle and of structural features of HCV proteins have led to the discovery of numerous potential targets for antiviral therapy. Viral replication and polyprotein processing have been tagged as promising viral targets. Clathrin-mediated endocytosis, fusion of HCV with cellular membranes, translation of viral RNA, virus production and release as well as several host cell factors may provide alternative targets for future anti-HCV therapies. Several compounds are currently under investigation in clinical trials and showed high antiviral activity in patients with chronic hepatitis C. Recently, Phase III studies for two protease inhibitors, telaprevir and boceprevir, each given in combination with pegylated interferon (standard of care [SOC]), were completed. In HCV-genotype-1-infected patients, the addition of telaprevir or boceprevir to SOC increased sustained virological response rates from <50% to >70%. Nucleoside/nucleotide inhibitors of the HCV NS5B polymerase have shown antiviral activity against different HCV genotypes, and have a higher barrier to resistance than protease inhibitors. In addition, several allosteric binding sites have been identified for non-nucleoside inhibitors of the NS5B polymerase. Inhibitors of NS5A are potentially active against all HCV genotypes. Among the different host cell-targeting compounds, cyclophilin inhibitors have shown promising results. Future hope lies in the combination of direct-acting antiviral agents with the possibility of interferon-free treatment regimens.

Pharmaceutical aspects of the recombinant human serum albumin dimer: structural characteristics, biological properties, and medical applications

Human serum albumin is the most abundant protein in the blood. It is clinically used in the treatment of severe hypoalbuminemia and as a plasma expander. The use of albumins as a carrier for drugs is currently being developed, and some are now in the preclinical and clinical trial stages. The main technologies for utilizing an albumin as a drug carrier are protein fusion, polymerization and surface modification, and so on. Among these technologies, albumin dimerization has wide clinical applications as a plasma expander as well as a drug carrier. Despite the fact that many reports have appeared on drugs using an albumin dimer as a carrier, our knowledge of the characteristics of the albumin dimer itself is incomplete. In this review, we summarize the structural characteristics of recombinant albumin dimers produced by two methods, namely, chemical linkage with 1,6-bis(maleimido)hexane and genetically linked with an amino acid linker, and the physicochemical characteristics and biological properties of these preparations. Finally, the potential for pharmaceutical applications of albumin dimers in clinical situations is discussed.

Cost-effectiveness and population outcomes of general population screening for hepatitis C

BACKGROUND

Current US guidelines recommend limiting hepatitis C virus (HCV) screening to high-risk individuals, and 50%-75% of infected persons remain unaware of their status.

METHODS

To estimate the cost-effectiveness and population-level impact of adding one-time HCV screening of US population aged 20-69 years to current guidelines, we developed a decision analytic model for the screening intervention and Markov model with annual transitions to estimate natural history. Subanalyses included protease inhibitor therapy and screening those at highest risk of infection (birth year 1945-1965). We relied on published literature and took a lifetime, societal perspective.

RESULTS

Compared to current guidelines, incremental cost per quality-adjusted life year gained (ICER) was $7900 for general population screening and $4200 for screening by birth year, which dominated general population screening if cost, clinician uptake, and median age of diagnoses were assumed equivalent. General population screening remained cost-effective in all one-way sensitivity analyses, 30 000 Monte Carlo simulations, and scenarios in which background mortality was doubled, all genotype 1 patients were treated with protease inhibitors, and most parameters were set unfavorable to increased screening. ICER was lowest if screening was applied to a population with liver fibrosis similar to 2010 estimates. Approximately 1% of liver-related deaths would be averted per 15% of the general population screened; the impact would be greater with improved referral, treatment uptake, and cure.

CONCLUSIONS

Broader screening for HCV would likely be cost-effective, but significantly reducing HCV-related morbidity and mortality would also require improved rates of referral, treatment, and cure.

New therapies for chronic hepatitis C infection: a systematic review of evidence from clinical trials

INTRODUCTION

Hepatitis C virus (HCV) affects approximately 3% of the world population. The current standard of care for treatment of HCV is a combination of pegylated interferon and ribavirin. Approximately 10% of patients will stop treatment and 30% of patients require dose reduction because of side effects. For genotype 1 HCV-infected patients, only 40% of patients will achieve undetectable viral load 26 weeks posttreatment.

AIMS

The objectives of this review were to identify new treatments that are in clinical trials. These include boceprevir and telaprevir which are in routine clinical use and form part of the American Association for the Study of Liver Diseases (AASLD) 2011 guidelines as well as drugs based on observational studies, improving/modifying ribavirin or interferon-based therapies, modifying the host response and finally the use of direct-acting antiviral agents (DAA).

MATERIALS AND METHODS

  MEDLINE and EMBASE databases were searched from 2008 to 2011 for treatments for hepatitis C. Furthermore, abstracts and poster presentations for the annual European Association Study of the Liver, AASLD, Digestive Disease Week and Asian Pacific Association for the study of the Liver were searched for relevant material.

RESULTS

All four classes of DAA; NS3/NS4a serine protease inhibitors, cyclophilin inhibitors, NS5b polymerase inhibitors and NS5a inhibitors, show good success rates. Trials have been performed without ribavirin or interferon and demonstrate good antiviral activity with a decreased side effect profile. Combinations of DAA are a promising area of research with a high success rate.

CONCLUSIONS

Clinical trials show that future HCV therapy could be personalised, achieve higher success rates with decreased adverse incidents.

Pharmacology and therapeutic potential of interferons

Interferon (IFN) is widely recognised to be an integral part of the innate immune response to viral infection. Since its initial discovery in 1957 by Isaacs and Lindenmann, various IFN sub-types have been identified and there are now three distinct classes recognised-Type I (IFN-α and IFN-β), Type II (IFN-γ) and Type III (IFN-λ), distinguished by their differing receptors. As well as displaying profound antiviral activity in vivo, IFN has anti-proliferative, cytotoxic and anti-tumoural roles. In an attempt to harness their immunomodulatory potential, investigators and clinicians have investigated the use of IFNs for the treatment of human diseases with considerable success. For example, IFN-α preparations are now a critical component in the treatment of chronic Hepatitis C infection and IFN-β therapy is now the first line treatment for relapsing remitting multiple sclerosis. However, IFN therapy is also associated with significant morbidity and in some patients is poorly tolerated. In this review, we explore the scientific basis for IFN therapy and outline its therapeutic scope. We describe the commonly encountered side effects and attempt to explain the less well recognised pulmonary complications including emerging evidence of life threatening and irreversible pulmonary vascular pathology. Finally, we look to the future of interferon drug treatment, examining the potential for emerging therapies.

Drug development: longer-lived proteins

Protein therapeutics represent a powerful class of clinically approved drugs for the prevention and treatment of various diseases. Once administered, the biological fate of protein therapeutics is governed by the body's various complex biochemical and biophysical clearance mechanisms, several of which may decrease the drug's circulation time and efficiency. In this tutorial review, we introduce the concepts of physiological protein clearance from the body, and describe several chemical modification and protein engineering approaches used to improve the life span of administered protein therapeutics.

Viral clearance is associated with improved insulin resistance in genotype 1 chronic hepatitis C but not genotype 2/3

OBJECTIVES

Genotype-specific associations between hepatitis C virus (HCV) and insulin resistance (IR) have been described, but a causal relationship remains unclear. This study investigated the association between a sustained virological response (SVR) and IR after chronic HCV therapy.

METHODS

2255 treatment-naive patients with chronic HCV genotype 1 or 2/3 were enrolled in two phase 3 trials of albinterferon alpha-2b versus pegylated interferon alpha-2a for 48 or 24 weeks, respectively. IR was measured before treatment and 12 weeks after treatment using homeostasis model assessment (HOMA)-IR.

RESULTS

Paired HOMA-IR measurements were available in 1038 non-diabetic patients (497 with genotype 1; 541 with genotype 2/3). At baseline the prevalence of HOMA-IR >3 was greater in patients with genotype 1 than 2/3 (33% vs 27%; p=0.048). There was a significant reduction in the prevalence of IR in patients with genotype 1 achieving SVR (δ 10%; p<0.001), but not in genotype 1 non-responders or those with genotype 2/3. Multivariate analysis indicated that SVR was associated with a significant reduction in mean HOMA-IR in patients with genotype 1 (p=0.004), but not in those with genotype 2/3, which was independent of body mass index, alanine transaminase, γ-glutamyl transpeptidase and lipid level changes.

CONCLUSIONS

SVR is associated with a reduction in HOMA-IR in patients with HCV genotype 1 but not in those with genotype 2/3. Genotype 1 may have a direct effect on the development of IR, independent of host metabolic factors, and may be partially reversed by viral eradication.

Clinical impact of serum proteins on drug delivery

Among serum proteins albumin and transferrin have attracted the most interest as drug carriers in the past two decades. Prior to that, their potential use was overshadowed by the advent of monoclonal antibodies that was initiated by Milstein and Koehler in 1975. Meanwhile intensive pursuit of exploiting transferrin, but above all albumin as an exogenous or endogenous carrier protein for treating various diseases, primarily cancer, rheumatoid arthritis, diabetes and hepatitis has resulted in several marketed products and numerous clinical trials. While the use of transferrin has clinically been primarily restricted to immunotoxins, albumin-based drug delivery systems ranging from albumin drug nanoparticles, albumin fusion protein, prodrugs and peptide derivatives that bind covalently to albumin as well as physically binding antibody fragments and therapeutically active peptides are in advanced clinical trials or approved products. For treating diabetes, Levemir and Victoza that are myristic acid derivatives of human insulin or glucagon-like peptide 1 (GLP-1) act as long-acting peptides by binding to the fatty acid binding sites on circulating albumin to control glucose levels. Levemir from Novo Nordisk has already developed into a blockbuster since its market approval in 2004. Abraxane, an albumin paclitaxel nanoparticle as a water-soluble galenic formulation avoiding the use of cremophor/ethanol, transports paclitaxel through passive targeting as an albumin paclitaxel complex to the tumor site and is superior to conventional Taxol against metastatic breast cancer. INNO-206, an albumin-binding doxorubicin prodrug that also accumulates in solid tumors due to the enhanced permeability and retention (EPR) effect but releases the parent drug through acid cleavage, either intra- or extracellularly, is entering phase II studies against sarcoma. An expanding field is the use of albumin-binding antibody moieties which do not contain the fragment crystallizable (Fc) portion of, conventional immunoglobulin G (IgG) but are comprised of monovalent or bivalent light and/or heavy chains and incorporate an additional albumin-binding peptide or antibody domain. The most advanced antibody of this kind is ATN-103 (Ozoralizumab), a trivalent albumin-binding nanobody that neutralizes the pro-inflammatory tumor necrosis factor alpha (TNF-α) as a causative agent for exacerbating rheumatoid arthritis. ATN-103 is currently in multi-center phase II trials against this debilitating disease. In summary, because albumin as the most abundant circulating protein cannot only be used to improve the pharmacokinetic profile of therapeutically relevant peptides and the targeting moiety of antibodies but also for peptide-based targeting as well as low-molecular weight drugs to inflamed or malignant tissue, it is anticipated that R&D efforts of academia and the pharmaceutical industry in this field of drug delivery will prosper.

Beneficial IL28B genotype associated with lower frequency of hepatic steatosis in patients with chronic hepatitis C

BACKGROUND & AIMS

IL28B polymorphisms have been associated with both treatment induced and spontaneous clearance of hepatitis C virus (HCV). We previously found that LDL cholesterol levels were higher in chronic hepatitis C (CHC) patients with the CC genotype at the rs12979860 polymorphism, located proximal to the IL28 gene. Here we analyzed the association of steatosis with IL28B genotype in treatment naïve patients with CHC.

METHODS

Two independent cohorts of 145 genotype 1 infected patients from an antifibrotic study and 180 genotype 1 patients from Duke were analyzed for the presence and severity of steatosis in relation to the rs12979860 polymorphism at the IL28B locus. TaqMan assay based genotyping classified three groups CC, CT, and TT.

RESULTS

CC genotype was associated with a lower prevalence of steatosis. In the antifibrotic study, steatosis was found in 47.6% (50/105) of IL28B non-CC vs. 22.5% (9/40; p=0.008) in CC patients. Similarly, steatosis was found in 67.4% (89/132) of non-CC patients compared to only 39.6% (19/48; p=0.001) of CC patients in the Duke cohort.

CONCLUSIONS

IL28B CC genotype is associated with less pronounced disturbances of lipid metabolism, as reflected both in serum lipoprotein levels and hepatic steatosis, in HCV infection.

FibroSURE and FibroScan in relation to treatment response in chronic hepatitis C virus

AIM

To compare histological endpoint assessment using noninvasive alternatives to biopsy during treatment in a chronic hepatitis C virus (HCV) cohort.

METHODS

Patients with chronic HCV were randomized to receive interferon-based therapy for 24 (genotypes 2/3) or 48 (genotype 1) wk. FibroSURE™ (FS) was assessed at baseline and at week-12 post-treatment follow-up. Baseline biopsy for METAVIR was assessed by a single pathologist. FibroScan(®) transient elastography (TE) was performed during treatment in a patient subset.

RESULTS

Two thousand and sixty patients (n = 253 in Asia) were classified as METAVIR F0-1 (n = 1682) or F2-4 (n = 378). For F2-4, FS (n = 2055) had sensitivity and specificity of 0.87 and 0.61, respectively, with area under the receiver-operating curve of 0.82; corresponding values for TE (n = 214) and combined FS/TE (n = 209) were 0.77, 0.88 and 0.88, and 0.93, 0.68 and 0.88. Overall FS/TE agreement for F2-4 was 71% (κ = 0.41) and higher in Asians vs non-Asians (κ = 0.86 vs 0.35; P < 0.001). Combined FS/TE had 97% accuracy in Asians (n = 33). Baseline FS (0.38 vs 0.51, P < 0.001) and TE (8.0 kPa vs 11.9 kPa, P = 0.006) scores were lower in patients with sustained virological response than in nonresponders, and were maintained through follow-up.

CONCLUSION

FS and TE may reliably differentiate mild from moderate-advanced disease, with a potential for high diagnostic accuracy in Asians with chronic HCV.

Impact of albumin on drug delivery--new applications on the horizon

Over the past decades, albumin has emerged as a versatile carrier for therapeutic and diagnostic agents, primarily for diagnosing and treating diabetes, cancer, rheumatoid arthritis and infectious diseases. Market approved products include fatty acid derivatives of human insulin or the glucagon-like-1 peptide (Levemir(®) and Victoza(®)) for treating diabetes, the taxol albumin nanoparticle Abraxane(®) for treating metastatic breast cancer which is also under clinical investigation in further tumor indications, and (99m)Tc-aggregated albumin (Nanocoll(®) and Albures(®)) for diagnosing cancer and rheumatoid arthritis as well as for lymphoscintigraphy. In addition, an increasing number of albumin-based or albumin-binding drugs are in clinical trials such as antibody fusion proteins (MM-111) for treating HER2/neu positive breast cancer (phase I), a camelid albumin-binding nanobody anti-HSA-anti-TNF-α (ATN-103) in phase II studies for treating rheumatoid arthritis, an antidiabetic Exendin-4 analog bound to recombinant human albumin (phase I/II), a fluorescein-labeled albumin conjugate (AFL)-human serum albumin for visualizing the malignant borders of brain tumors for improved surgical resection, and finally an albumin-binding prodrug of doxorubicin (INNO-206) entering phase II studies against sarcoma and gastric cancer. In the preclinical setting, novel approaches include attaching peptides with high-affinity for albumin to antibody fragments, the exploitation of albumin-binding gadolinium contrast agents for magnetic resonance imaging, and physical or covalent attachment of antiviral, antibacterial, and anticancer drugs to albumin that are permanently or transiently attached to human serum albumin (HSA) or act as albumin-binding prodrugs. This review gives an overview of the expanding field of preclinical and clinical drug applications and developments that use albumin as a protein carrier to improve the pharmacokinetic profile of the drug or to target the drug to the pathogenic site addressing diseases with unmet medical needs.

Interferon combination therapy for HIV/hepatitis C virus coinfection

IFN-α has been the cornerstone of chronic hepatitis C virus (HCV) treatment for over a decade. Yet, rates of sustained virologic response of HCV infection to interferon-based therapy, particularly in difficult-to-treat populations, have been disappointingly low. This is particularly true in HIV/HCV coinfection, in which less than a third of patients typically respond to therapy. New HCV protease inhibitors, most of which will need to be administered with pegylated interferon, are in development, but comprehensive, long-term data for their use in coinfected patients is not yet available. Understanding the basis of this population's poor response to interferon-based therapy is crucial to future exploration of new therapeutic options, immunotherapy and prognosis in HIV/HCV-coinfected population.

Response to antiviral therapy in patients with genotype 3 chronic hepatitis C: fibrosis but not race encourages relapse

BACKGROUND AND AIMS

We completed a retrospective analysis of patients with genotype 3 hepatitis C virus (HCV) undergoing therapy in four UK centres with large populations of patients from the Indian subcontinent.

MATERIALS AND METHODS

Notes on all patients treated with pegylated interferon and ribavirin were reviewed and factors that influenced the response were examined.

RESULTS

Six hundred and four patients with genotype 3 HCV were studied, of whom 299 were Asians. Median age was 43 years, 65% were men and 24% had cirrhosis. Overall, 457 (76%) patients achieved sustained virological response (SVR). By multivariable analysis it was found that ethnicity was not associated with an impaired response but age, cirrhosis and diabetes were significantly associated with a reduced SVR, the likelihood of a response was reduced by 25% per 10-year increment in age, by 59% among individuals with cirrhosis and by 62% among individuals with diabetes mellitus. Most patients who did not achieve an SVR relapsed (15%) rather than failing to achieve an end of treatment response.

CONCLUSION

The response to antiviral therapy in genotype 3 HCV is not affected by South Asian (vs. Caucasian) ethnicity, but age, cirrhosis and diabetes reduce the response. Treatment failure most often is due to relapse.

Strategies for extended serum half-life of protein therapeutics

With a growing number of protein therapeutics being developed, many of them exhibiting a short plasma half-life, half-life extension strategies find increasing attention by the biotech and pharmaceutical industry. Extension of the half-life can help to reduce the number of applications and to lower doses, thus are beneficial for therapeutic but also economic reasons. Here, a comprehensive overview of currently developed half-life extension strategies is provided including those aiming at increasing the hydrodynamic volume of a protein drug but also those implementing recycling processes mediated by the neonatal Fc receptor.

Peptide-modified albumin carrier explored as a novel strategy for a cell-specific delivery of interferon gamma to treat liver fibrosis

Excessive accumulation of the extracellular matrix proteins primarily produced by activated hepatic stellate cells (HSC) leads to liver fibrosis. To date, no successful therapeutic intervention is available for the treatment of this disease. Platelet derived growth factor beta receptor (PDGFβR) is highly upregulated on disease-inducing activated HSC and thus can be used for delivery of antifibrotic drugs to increase therapeutic efficacy with reduced adverse effects. Interferon gamma (IFNγ) has been recognized as a potent antifibrotic cytokine; however, poor pharmacokinetics and side effects due to frequent administration have limited its clinical use. For HSC-specific delivery, a PDGFβR-specific drug delivery carrier (PPB-HSA) was developed by modifying albumin with PDGFβR-recognizing cyclic peptides. Subsequently, IFNγ was conjugated to PPB-HSA via bifunctional PEG linkers to synthesize PPB-HSA-PEG-IFNγ. In vitro, PPB-HSA-PEG-IFNγ retained complete biological activity similar to unmodified IFNγ and showed PDGFβR-specific binding to human HSC and primary culture-activated rat HSC. In TGFβ-stimulated mouse fibroblasts and human HSC, PPB-HSA-PEG-IFNγ induced significant reduction in crucial fibrotic parameters. In vivo, the conjugate rapidly accumulated into PDGFβR-expressing HSC in fibrotic livers and activated IFNγ-mediated pstat1α signaling pathway. Furthermore, in a CCl(4)-induced acute liver injury model in mice, treatment with HSC-targeted IFNγ strongly ameliorated hepatic fibrogenesis by inducing significant reduction (about 60%; p < 0.01) in collagen I and α-SMA expression as well as enhanced fibrolysis (increased MMP/TIMP ratio; p < 0.05) while free unmodified IFNγ was ineffective. Furthermore, in contrast to free native IFNγ, the conjugate did not induce macrophage infiltration and IL-1β expression in the liver. In conclusion, these data demonstrate the enhanced antifibrotic efficacy and reduced off-target effects of PPB-HSA-PEG-IFNγ conjugate showing the potential of cell-specific targeting of IFNγ for the treatment of liver fibrosis.