Granulocyte colony-stimulating factor dosing in pegylated interferon alpha-induced neutropenia and its impact on outcome of anti-HCV therapy

Feasibility of pegylated interferon and ribavirin in hepatitis C-related cirrhosis with neutropenia or thrombocytopenia

AIM

To investigate the feasibility of pegylated interferon plus ribavirin treatment in cirrhotic patients who presented with, or developed while on-treatment, platelet counts ≤ 80,000/μL and/or neutrophil counts ≤ 1,500/μL.

METHODS

A retrospective analysis of prospectively gathered data on 123 cirrhotic patients treated with pegylated interferon and ribavirin. Adverse effects and haematological changes were monitored: bleeding and infectious events were registered and related to platelet and absolute neutrophil counts.

RESULTS

Among the 58 patients (47.2%) with nadir platelets ≤ 50,000/μL during therapy, 6 (10.3%) experienced a bleeding episode; of the remaining 65 patients with platelets constantly >50,000/μL, 3 (4.6%) bled. Of the 11 bleedings, 3 manifested during an infection, while patients had platelets >50,000/μL. Nadir neutrophils ≤ 750/μL occurred in 45 patients (38.2%) during treatment, and 14 of them (29.8%) had an infectious event. Infections were also documented in 18 of the 76 patients (23.7%) with neutrophils constantly >750/μL.

CONCLUSIONS

The study reveals the feasibility of treating cirrhotic patients with cytopenia with pegylated interferon and ribavirin, as bleeding or infectious events under therapy were unrelated to platelet and neutrophil counts. Withdrawal of therapy or variations in the pre-assigned dosages of either pegylated interferon or ribavirin owing to abnormally low haematological parameters seems to no longer be tenable.

Low dose of interferon-α improves the clinical outcomes of docetaxel in patients with castration-resistant prostate cancer: A pilot study

The aim of this study was to test whether a low dose of interferon-α-2b (IFN-α2b) enhances the clinical outcome of docetaxel (DXT) in patients with castration-resistant prostate cancer (CRPC). A prospective controlled trial of 40 CRPC patients receiving 5 mg of prednisone twice daily was conducted, where patients were randomly assigned to be administered 75 mg/m² DXT plus 3 mIU/m² IFN-α2b (group A, n=20) or 75 mg/m² DXT alone (group B, n=20). The prostate-specific antigen (PSA) response, tumor response, progression-free survival (PFS) and overall survival (OS) were evaluated. There was no statistically significant difference in PSA response rate between groups A and B (65 vs. 47.4%, P=0.341). The tumor response rate in group A was significantly greater compared with that in group B (55 vs. 21.1%, P=0.048). The median PFS was longer in group A compared with that in group B (10 vs. 8 months, P=0.043). There was no statistically significant difference in median OS between the two groups (19 vs. 17 months, P=0.348), but one patient displayed a complete tumor response in group A. In groups A and B, transient grade 3 to 4 neutropenia was observed in nine and six patients, grade 3 to 4 anemia was observed in three and five patients, and grade 3 to 4 general fatigue was observed in four and one patient(s), respectively. The proportion of patients with grade 3 to 4 toxicity was not statistically different between the two groups. A low dosage of IFN-α2b may improve the antitumor activity of DXT with an acceptable toxicity profile in patients with CRPC.

Low-dose pegylated interferon-α2a plus ribavirin therapy for elderly and/or cirrhotic patients with HCV genotype-1b and high viral load

BACKGROUND

Pegylated interferon (PEG-IFN) plus ribavirin therapy is still recommended for elderly and/or cirrhotic patients. This study examined whether sustained virological response (SVR) to low-dose PEG-IFN-α2a plus ribavirin therapy for elderly and/or cirrhotic patients could be predicted based on viral reduction within 2 weeks after therapy initiation or interleukin IL-(28B) polymorphism and viral mutations.

METHODS

Participants comprised 115 elderly (≥65 years) and/or cirrhotic patients with genotype-1b and high viral load. Reduced doses of PEG-IFN-α2a (90 μg/kg/week) and ribavirin (400-800 mg/day) were administered for 48-72 weeks based on virological response of each patient.

RESULTS

SVR was achieved in 34% (39/115), and treatment was discontinued in 15% (17/115). Univariate analysis identified age, α-fetoprotein, fibrosis marker, interferon sensitivity-determining region (ISDR), IL-28B polymorphism and level of viral reduction within 2 weeks as factors contributing significantly to SVR. However, no significant differences were noted in core amino acid substitutions. Multivariate analysis identified age, hyaluronic acid, ISDR and viral reduction as factors independently associated with SVR. Positive predictive value (PPV) and negative predictive value (NPV) of SVR based on the level of viral reduction at 2 weeks (cutoff level, 1.7 log IU/ml) were 83% and 84%, respectively. The PPV of SVR based on IL-28B major and ISDR mutant was 70%, and the NPV of SVR based on IL-28B minor and wild-type ISDR was 89%.

CONCLUSIONS

Evaluations of viral reduction at 2 weeks or both IL-28B and ISDR are useful to predict SVR to low-dose PEG-IFN-α2a plus ribavirin therapy for elderly and/or cirrhotic patients.

Low-dose pegylated interferon-alpha-2a monotherapy in elderly and/or cirrhotic patients infected with hepatitis C virus genotype-2 or genotype-1 low level infection

AIM

Elderly and/or cirrhotic patients with hepatitis C virus (HCV) are at high risk of adverse effects during interferon therapy. The aim of the present study was to evaluate the efficacy, safety and predictive factors for sustained virological response (SVR) of low-dose pegylated interferon-α-2a (PEG IFN-α-2a) monotherapy in elderly and/or cirrhotic patients with HCV genotype-2 or genotype-1 low level infection.

METHODS

Sixty-four elderly (≥65 years) and/or cirrhotic patients with HCV genotype-2 or genotype-1 low level (<5 logIU/mL) infection underwent low-dose PEG IFN-α-2a (90 μg/week) monotherapy for 24 weeks. Sixty patients were available for efficacy assessment.

RESULTS

SVR was achieved in 78.3%. SVR rates according to genotype-1 low, genotype-2 low and genotype-2 high viral load were 90.0%, 87.1% and 57.9%, respectively. The discontinuation rate was 12.5%. PEG IFN-α-2a was interrupted or discontinued in four patients because of severe thrombocytopenia (<25 000/mm(3) ). The baseline platelet counts of all these patients were less than 70 000/mm(3) . On univariate analysis of factors contributing to SVR, significant differences were noted in viral load, platelet count, γ-glutamyltransferase, ferritin, α-fetoprotein level and rapid viral response (RVR). On multivariate analysis, RVR was the only independent factor (P = 0.010, odds ratio = 47.27). The positive and negative SVR-predictive values based on RVR were 95% and 82%, respectively.

CONCLUSION

Low-dose PEG IFN-α-2a monotherapy was effective and tolerable in elderly and/or cirrhotic patients with genotype-2 or genotype-1 low HCV level infection. However, a baseline platelet count of more than 70 000/mm(3) is needed for safety. RVR can predict SVR accurately.

Recent trends in the treatment of chronic hepatitis C

Pegylated interferon and ribavirin combination therapy is accepted as the standard antiviral treatment for chronic hepatitis C regardless of HCV genotype. This combination therapy achieves higher response rates than previous therapy, but, nevertheless, a large proportion of patients suffer from treatment failure or adverse events. Recent clinical studies of viral kinetics during antiviral treatment have led to the introduction of response-guided therapy, the concept of 'customized therapy depending on viral response', which focuses on modulation of the treatment period depending on the viral response to create a sustained viral response without unnecessary medication and costs. New upcoming direct-acting antivirals (DAAs) maximize response rate, and triple therapy including DAAs along with pegylated interferon and ribavirin combination therapy could soon be the standard therapy. In this article, we reviewed the factors affecting treatment, response guided treatment, retreatment after failure of standard treatment, management of adverse events during treatment, and new treatment options.

Granulocyte colony-stimulating factor mobilizes CD34(+) cells and improves survival of patients with acute-on-chronic liver failure

BACKGROUND & AIMS

Acute-on-chronic liver failure (ACLF) develops in patients with chronic liver disease and has high mortality. Mobilization of bone marrow-derived stem cells with granulocyte colony-stimulating factor (G-CSF) could promote hepatic regeneration.

METHODS

Consecutive patients with ACLF were randomly assigned to groups given 5 μg/kg G-CSF subcutaneously (12 doses; group A, n = 23) or placebo (group B, n = 24) plus standard medical therapy. We assessed survival until day 60; Child-Turcotte-Pugh (CTP), Model for End-Stage Liver Disease (MELD), and Sequential Organ Failure Assessment (SOFA) scores; and the development of other related complications.

RESULTS

After 1 week of treatment, group A had higher median leukocyte and neutrophil counts than group B (P < .001). Sixteen patients in group A (69.6%) and 7 in group B (29%) survived; the actuarial probability of survival at day 60 was 66% versus 26%, respectively (P = .001). Treatment with G-CSF also reduced CTP scores in group A by a median of 33.3% compared with an increase of 7.1% in group B (P = .001), along with MELD (median reduction of 15.3% compared with an increase of 11.7% in group B; P = .008) and SOFA scores (median reduction of 50% compared with an increase of 50% in group B; P = .001). The percentages of patients who developed hepatorenal syndrome, hepatic encephalopathy, or sepsis were lower in group A than in group B (19% vs 71% [P = .0002], 19% vs 66% [P = .001], and 14% vs 41% [P = .04], respectively). After 1 month of treatment, G-CSF increased the number of CD34(+) cells in the liver (by 45% compared with 27.5% in group B; P = .01).

CONCLUSIONS

G-CSF therapy more than doubles the percentage of patients with ACLF who survive for 2 months; it also significantly reduces CTP, MELD, and SOFA scores and prevents the development of sepsis, hepatorenal syndrome, and hepatic encephalopathy.

Randomized trial comparing dose reduction and growth factor supplementation for management of hematological side effects in HIV/hepatitis C virus patients receiving pegylated-interferon and ribavirin

BACKGROUND

Pegylated-interferon (PEG-IFN) and ribavirin (RBV), current standard treatment for hepatitis C virus (HCV) infection, are frequently associated with neutropenia and anemia, leading to high treatment discontinuation rates in HIV/HCV-coinfected patients. Our objective was to compare the effectiveness of intervening with hematologic growth factors versus dose reductions of standard HCV therapy for the management of treatment-induced hematologic disorders.

METHODS

Ninety-two HIV/HCV-coinfected, therapy-naive subjects received PEG-IFN alfa-2b 1.5 μg·kg⁻¹·wk⁻¹ and RBV 13 ± 2 mg·kg⁻¹·d⁻¹ for up to 48 weeks. Before treatment initiation, subjects were randomized to subsequently receive growth factors, recombinant human erythropoietin (rHuEPO) and/or granulocyte colony-stimulating factor, or dose reduction (RBV and/or PEG-IFN) for anemia and neutropenia management, respectively. We analyzed the ability of each management strategy to control anemia and neutropenia and the percentage of subjects who achieved a successful treatment outcome according to the different management strategies.

RESULTS

During treatment, 43 subjects developed anemia (human erythropoietin, n = 24; dose reduction, n = 19), whereas 25 subjects developed neutropenia (granulocyte colony-stimulating factor, n = 10; dose reduction, n = 15). After the intervention, the increase in both hemoglobin and absolute neutrophil counts did not differ between the 2 side effect management strategies. Sustained response percentages were similar comparing anemic and neutropenic subjects regardless of management strategy (anemia: recombinant human erythropoietin, 29% versus dose reduction, 21%, P = 0.92; neutropenia: granulocyte colony-stimulating factor, 40% versus dose reduction, 20%, P = 0.46).

CONCLUSIONS

Growth factor supplementation and dose reduction do not seem to differ as management strategies for anemia and neutropenia in HIV/HCV-coinfected individuals treated with PEG-IFN/RBV.

Colony-stimulating factors in the prevention and management of infectious diseases

Colony-stimulating factors (CSFs) are attractive adjunctive anti-infective therapies. Used to enhance innate host defenses against microbial pathogens, the myeloid CSFs increase absolute numbers of circulating innate immune effector cells by accelerating bone marrow production and maturation, or augment the function of those cells through diverse effects on chemotaxis, phagocytosis, and microbicidal functions. This article summarizes the evidence supporting the accepted clinical uses of the myeloid CSFs in patients with congenital or chemotherapy-induced neutropenia, and presents an overview of proposed and emerging uses of the CSFs for the prevention and treatment of infectious diseases in other immunosuppressed and immunocompetent patient populations.

Granulocyte colony-stimulating factor for hepatitis C therapy-associated neutropenia: systematic review and economic evaluation

Hepatitis C virus (HCV) treatment requires maximal adherence to pegylated interferon (Peg-IFN) and ribavirin to achieve a sustained virologic response (SVR). Neutropenia is the most common cause for Peg-IFN dose reduction. Our objectives were to evaluate the effectiveness, safety and cost-effectiveness of granulocyte colony-stimulating factor (G-CSF) versus Peg-IFN dose reduction for HCV therapy-associated neutropenia in treatment naïve adults. We conducted a systematic review to identify controlled trials and observational studies. Study selection, quality assessment and data extraction were completed independently by two investigators. Cost-effectiveness and cost-utility analyses compared G-CSF with dose reduction. Nineteen studies were included. In one trial, the SVR for those receiving G-CSF was 54.5% (95% CI: 34.7-73.1) compared with 26.3% (95% CI: 11.8-48.8) for dose reduction. The remaining studies were case series or retrospective cohorts and provided weak evidence for the relationship between SVR and G-CSF. The risk of adverse events, including infection, associated with G-CSF was low (13.1%; 95% CI: 8.0-20.8) and clinically insignificant. G-CSF had an incremental cost-effectiveness ratio of $41,701 per SVR achieved in genotype 1, and $16,115 per SVR achieved in genotype 2 or 3. Estimates were robust under a variety of resource and intervention scenarios. While administration of G-CSF may enable patients to remain on or resume optimal HCV therapy, there was weak evidence that this improves the likelihood of SVR compared with dose reduction. Adverse effects of G-CSF are mild. The economic evaluation was inconclusive.

Acute septic shock during pegylated-interferon and ribavirin therapy in a patient with chronic hepatitis C who underwent aortic graft replacement

We report an autopsied case of a 59-year-old woman with acute septic shock from methicillin-resistant Staphylococcus aureus (MRSA) infection during combination therapy with pegylated-interferon-α-2b (PEG-IFNα-2b) and ribavirin. She underwent aortic graft replacement for the treatment of a dissecting aneurysm. We observed her latent infection closely for over a year following the operation. The clinical and laboratory examinations did not show any sign of infection. She then underwent PEG-IFNα-2b/ribavirin combination therapy. In her 17th week of therapy, she suddenly complained of high fever followed by a markedly rapid progression of sepsis and disseminated intravascular coagulation. She died of acute septic shock from MRSA infection on her fourth hospital day. Autopsy revealed abscess formation in the mediastinum around the artificial vessel graft. There was no obvious verruca on the internal surface of the replaced graft. Microscopic examination revealed numerous cocci along the thread in the suture of the graft. This clinical experience shows that combination therapy with PEG-IFNα-2b/ribavirin for the treatment of chronic hepatitis C should be given careful consideration when administered to patients who have undergone major vessel surgery, such as aortic graft replacement. Once the treatment has been started, infection should be monitored with particular care and frequent medical examinations.

Safety and efficacy of treatment for chronic hepatitis C with a focus on pegylated interferons: the backbone of therapy today and in the future

INTRODUCTION

Approximately 170 million people are infected with HCV. The efficacy of treatment for chronic hepatitis C has increased markedly over the last 2 decades. Optimal patient management requires thorough knowledge of the adverse effect profiles of drugs used for this condition and strategies to mitigate these effects.

AREAS COVERED

The efficacy, safety and tolerability data associated with IFN-based therapy, with particular attention given to the two licensed pegylated IFNs (peg-IFNs), are identified by focused searches of Medline. Recommendations for the management of adverse events are also given. Focused searches of PubMed are done using the terms peginterferon and chronic hepatitis C. The results of large randomized clinical trials are emphasized.

EXPERT OPINION

Patients receiving treatment with peg-IFN plus ribavirin for chronic hepatitis C must be monitored closely for adverse events. These events can be effectively managed to maximize patients' adherence and thus the chance of treatment success. Direct-acting antiviral agents are expected to be approved in the near future and will be used in select patients with a peg-IFN plus ribavirin 'backbone'.

Interferon-α suppressed granulocyte colony stimulating factor production is reversed by CL097, a TLR7/8 agonist

BACKGROUND AND AIM

Neutropenia, a major side-effect of interferon-α (IFN-α) therapy can be effectively treated by the recombinant form of granulocyte colony stimulating factor (G-CSF), an important growth factor for neutrophils. We hypothesized that IFN-α might suppress G-CSF production by peripheral blood mononuclear cells (PBMCs), contributing to the development of neutropenia, and that a toll-like receptor (TLR) agonist might overcome this suppression.

METHODS

Fifty-five patients who were receiving IFN-α/ribavirin combination therapy for chronic hepatitis C virus (HCV) infection were recruited. Absolute neutrophil counts (ANC), monocyte counts and treatment outcome data were recorded. G-CSF levels in the supernatants of PBMCs isolated from the patients and healthy controls were assessed by enzyme-linked immunosorbent assay following 18 h of culture in the absence or presence of IFN- α or the TLR7/8 agonist, CL097.

RESULTS

Therapeutic IFN-α caused a significant reduction in neutrophil counts in all patients, with 15 patients requiring therapeutic G-CSF. The reduction in ANC over the course of IFN-α treatment was paralleled by a decrease in the ability of PBMCs to produce G-CSF. In vitro G-CSF production by PBMCs was suppressed in the presence of IFN-α; however, co-incubation with a TLR7/8 agonist significantly enhanced G-CSF secretion by cells obtained both from HCV patients and healthy controls.

CONCLUSIONS

Suppressed G-CSF production in the presence of IFN-α may contribute to IFN-α-induced neutropenia. However, a TLR7/8 agonist elicits G-CSF secretion even in the presence of IFN-α, suggesting a possible therapeutic role for TLR agonists in treatment of IFN-α-induced neutropenia.

Reduction in neutrophil count during hepatitis C treatment: drug toxicity or predictor of good response?

BACKGROUND

Bone marrow suppression is a well-recognized toxicity of the treatment of hepatitis C virus (HCV). Reduction of the peginterferon dose because of neutropenia is common in clinical practice. However, reduction of peginterferon dose during the first weeks of HCV treatment is associated with failure to achieve sustained virological response.

AIMS

The objective of this study is to investigate whether the fall of neutrophil count during hepatitis C treatment is associated with achieving sustained virological response.

METHODS

We performed an observational study of patients who completed peginterferon and ribavirin treatment in an Infectious Diseases Department in Manchester, UK.

RESULTS

Of the 74 patients included in the analysis, 78% had genotype 2 or 3 hepatitis C and 15% had liver cirrhosis. Sustained virological response was achieved in 78% of patients. On univariate analysis, factors related to achieving sustained virological response were younger age, genotype 2 or 3, baseline neutrophil count, and fall of neutrophil count during treatment. Multivariate analysis showed baseline neutrophil count >3.5 x 10(3) cells/mm(3) [odds ratio (OR) 5.7; 95% confidence interval (CI) 1.24-26.3] and a reduction of neutrophil count >60% (OR 4.5; 95% CI 1.03-19.9) to be independently associated with achieving sustained virological response. Neutropenia was not associated with an increased risk of infections.

CONCLUSIONS

In this observational study, higher baseline neutrophil count and fall of neutrophil count during the treatment of hepatitis C was associated with achieving sustained virological response. These findings could have important implications for the monitoring and management of HCV treatment with peginterferon if they are confirmed in other studies.

Granulocyte colony stimulating factor in HCV genotype-1 patients who develop Peg-IFN-alpha2b related severe neutropenia: a preliminary report on treatment, safety and efficacy

Dose reductions of Peg-IFNa because of severe neutropenia may affect the virologic response in patients with hepatitis C infection (HCV). Granulocyte colony-stimulating factor (G-CSF) has been used occasionally but studies addressing its safety and efficacy in the current treatment of HCV infection are missing. The database of 232 naïve patients with HCV genotype-1 who received PEG-IFNalpha2b 1.5 mcg/kg/week plus Ribavirin 800-1,400 mg/day and completed the treatment was examined. Nineteen patients who exhibited significant neutropenia and received 150-300 microg G-CSF (Group A) with 19 matched control patients who had dose reductions of Peg-IFNalpha according to the standard recommendations (Group B) were examined. None of the patients had treatment modifications due to thrombocytopenia or anemia. The mean decline of the neutrophils was similar in groups A and B (1,760 +/- 1,030/mm(3) at 11 +/- 8.6 weeks and 1,630 +/- 890 at 12.3 +/- 6.1, respectively). Nadir neutrophil values were also not statistically different. Patients who received G-CSF two before IFNalpha, maintained neutrophils between 1,400/mm(3) and 2,700/mm(3) and remained on G-CSF for 29 weeks (2-40). Virologic response at the end of treatment was observed in 12/19 (63%) patients and at 6 months follow-up in 6/19 (32%) in group A as compared to 9/19 (47%) and 4/19 (21%) in group B, respectively. No side effects related to G-CSF were encountered. Administration of G-CSF 2 days before Peg-IFNalpha is safe, maintains sustained neutrophil count, improves adherence to treatment and seems to increase the virologic response in patients infected with HCV genotype 1 who develop Peg-IFN-alpha2b related severe neutropenia.

Safety of peginterferon in the treatment of chronic hepatitis C

BACKGROUND

Combination of 'pegylated' interferons (IFNs) plus ribavirin, the standard treatment of chronic hepatitis C (CHC), is frequently associated with side effects. Anticipation, recognition and proper management of these side effects are important to ensure compliance with therapy and achievement of sustained virologic response.

OBJECTIVE

To illustrate the side effect profile of pegIFN-alpha in the treatment of CHC.

METHODS

Studies and abstracts were identified through a computerized, English language literature search. Key search terms included peginterferon and CHC. Information available only in abstract form was retrieved from national and international hepatology associations.

RESULTS

Most adverse events occurring with combination therapy can be anticipated and managed appropriately; therefore, premature discontinuation of therapy owing to side effects is not required in most patients.

Role of hematopoietic growth factors as adjuncts in the treatment of chronic hepatitis C patients

Drug-induced hematotoxicity is the most common reason for reducing the dose or withdrawing ribavirin (RBV) and interferon (IFN) therapy in chronic hepatitis C, which leads to the elimination of a possible cure for the patient. Traditionally, severe anemia and neutropenia have been considered as absolute contraindications to start antiviral therapy. This has not however, been the case since the advent of adjunct therapy with hematopoietic growth factors (erythropoietin (EPO) and granulocyte-colony stimulating factor (G-CSF)). Some recent landmark studies have used this adjunct therapy to help avoid antiviral dose reductions. Although the addition of this adjunct therapy has been shown to significantly increase the overall cost of the treatment, this extra cost is worth bearing if the infection is cured at the end of the day. Although more studies are needed to refine the true indications of this adjunct therapy, determine the best dose regimen, quantify the average extra cost and determine whether or not the addition of this therapy increases the sustained virological response rates achieved, the initial reports are encouraging. Therefore, although not recommended on a routine basis, some selected patients may be given the benefits of these factors. This article reviews the current literature on this subject and makes a few recommendations to help develop local guidelines.