Early virologic responses and hematologic safety of direct-acting antiviral therapies in veterans with chronic hepatitis C

Preclinical Pharmacological Development of Chlorcyclizine Derivatives for the Treatment of Hepatitis C Virus Infection

Hepatitis C virus (HCV) is a small, single-stranded, positive-sense RNA virus that infects more than an estimated 70 million people worldwide. Untreated, persistent HCV infection often results in chronic hepatitis, cirrhosis, or liver failure, with progression to hepatocellular carcinoma. Current anti-HCV regimens comprising direct acting antivirals (DAAs) can provide curative treatment; however, due to high costs there remains a need for effective, shorter-duration, and affordable treatments. Recently, we disclosed anti-HCV activity of the cheap antihistamine chlorcyclizine, targeting viral entry. Following our hit-to-lead optimization campaign, we report evaluation of preclinical in vitro absorption, distribution, metabolism, and excretion properties, and in vivo pharmacokinetic profiles of lead compounds. This led to selection of a new lead compound and evaluation of efficacy in chimeric mice engrafted with primary human hepatocytes infected with HCV. Further development and incorporation of this compound into DAA regimens has the potential to improve treatment efficacy, affordability, and accessibility.

Rapid virological response of telaprevir and boceprevir in a Brazilian cohort of HCV genotype 1 patients: a multicenter longitudinal study

Background

Chronic hepatitis C is a major public health issue, but there is a gap in the literature regarding the effectiveness and safety of direct-acting antiviral agents in the Brazilian population. The main aim of this study was to describe the effectiveness of boceprevir and telaprevir in patients treated at public health care institutions in Brazil.

Materials and methods

A prospective longitudinal and multicenter study was conducted in five centers in the State of Paraná between September 2014 and June 2016. Data regarding effectiveness and safety were collected from medical records of patients treated with boceprevir or telaprevir. The effectiveness outcome comprised the rapid virological response (RVR). Multivariate analysis was performed to verify the influence of independent variables (ie, age, gender, baseline viral load) on RVR achievement.

Results

Data were collected from 117 patients with chronic hepatitis C virus (HCV) genotype 1 infection. Fifteen patients received treatment with boceprevir and 102 received telaprevir. The mean age was 51.6 years, 64.1% were male, 44.4% were infected with HCV subtype 1a, 62.4% had a high baseline viral load (≥800,000 IU/mL) and 33% were cirrhotic. Furthermore, 79.5% of patients achieved RVR (26.7% in the boceprevir group and 87.3% in the telaprevir group). Multivariate analysis demonstrated that the type of protease inhibitor (boceprevir or telaprevir) and the baseline viral load had an influence on the RVR rate (odds ratio [OR] =0.011; 95% confidence interval [CI]: 0.001–0.119; P<0.001/OR =13.004; 95% CI: 1.522–111.115; P=0.019, respectively).

Conclusion

In this longitudinal multicenter cohort study conducted from the Brazilian perspective, differences were found in the RVR rates, favoring telaprevir over boceprevir for genotype 1 HCV-infected patients. In addition, the baseline viral load was associated with RVR achievement in both evaluated groups. As RVR is also reported in the literature as a predictor of the sustained virological response (SVR), further analyses of RVR as predictor of SVR outcomes should be further evaluated in Brazil.

A Primary Care-based Collaborative Hepatitis C Clinic: Clinical Structure and Virologic Outcomes with Direct Acting Antiviral Therapy

Background:

Currently 4 million persons in the US have active hepatitis C virus (HCV) infection and most have never successfully completed antiviral treatment. Newer therapies herald potential for wider uptake and acceptance of treatment, but the number of hepatology specialists is limited and newer models are needed to increase access to care. The aim of this study is to describe a collaborative primary care-based clinic for HCV treatment.

Methods:

Retrospective analysis of a collaborative primary care clinic developed for the evaluation and treatment of patients with chronic hepatitis C at one VA medical center. A half-day clinic was organized with 4 primary care MDs, 2 hepatologists, 2 nurse practitioners, and a co-located psychiatrist, pharmacist and nurse case manager. Clinic productivity and outcomes related to the number of patients who initiated and completed treatment with direct acting antivirals (DAA) and pegylated interferon and ribavirin were evaluated.

Results:

In this 18 month period, the clinic had 1890 confirmed HCV registry patients and 1690 clinic visits. 74 HCV genotype 1 patients initiated DAA therapy. Primary care providers treated 47 patients (32% cirrhotic) and hepatologists treated 27 patients (48% cirrhotic). Final SVR rate was 54.6% (39.2% cirrhotics vs. 65.2% noncirrhotics). SVR rates were higher in patients with primary care providers (61.7%) vs. hepatologists (44.4%). Despite numerous adverse events, early treatment termination for adverse events occurred in 5.3% vs. 21.3% for virologic non-response. Multivariate analysis revealed no significant differences between primary care and hepatology for SVR and treatment discontinuations.

Conclusion:

This clinic demonstrated effectiveness and safety with DAA therapy. This illustrates potential for a primary care based collaborative clinic, which will be crucial for expanding access to effective HCV care.

Cost-effectiveness of sofosbuvir for the treatment of chronic hepatitis C-infected patients

The efficacy of treatment for hepatitis C genotype 1 infection has significantly improved with the introduction of first-generation protease inhibitors. However, there remains a need for effective treatments for patients infected with other genotypes, for nonresponders and patients unsuitable for interferon. Sofosbuvir is the first nucleotide polymerase inhibitor with pan-genotypic activity. Sofosbuvir-based regimens have resulted in >90% sustained virological response across treatment-naïve genotype 1-6 patients in five phase III clinical trials of sofosbuvir administered with ribavirin or pegylated interferon and ribavirin. This analysis evaluates the cost-effectiveness of sofosbuvir within the current licensed indication, for genotype 1-6 in the UK. A Markov model followed a cohort of 10 000 patients over lifetime, with approximately 20% initiating treatment for compensated cirrhosis. Sofosbuvir-regimens were compared to telaprevir, boceprevir, pegylated interferon and ribavirin, or no treatment. Costs and outcomes were discounted at 3.5%. The cost perspective utilized costs applicable to the National Health Service in the UK. Sofosbuvir proved to be cost-effective in most patient populations with incremental cost-effectiveness ratios (ICERs) at £11 836/QALY and £7292/QALY against telaprevir and boceprevir, respectively. In genotype 3, sofosbuvir had a weighted ICER of £18 761/QALY. Sofosbuvir-based regimens are a cost-effective option for the majority of hepatitis C-infected patients in the United Kingdom although the incremental cost-effectiveness varies by genotype and regimen. Sofosbuvir and ribavirin is an alternative regimen for patients unsuitable for interferon.

Effectiveness and safety of first-generation protease inhibitors in clinical practice: Hepatitis C virus patients with advanced fibrosis

AIM: To evaluates the effectiveness and safety of the first generation, NS3/4A protease inhibitors (PIs) in clinical practice against chronic C virus, especially in patients with advanced fibrosis.

METHODS: Prospective study and non-experimental analysis of a multicentre cohort of 38 Spanish hospitals that includes patients with chronic hepatitis C genotype 1, treatment-naïve (TN) or treatment-experienced (TE), who underwent triple therapy with the first generation NS3/4A protease inhibitors, boceprevir (BOC) and telaprevir (TVR), in combination with pegylated interferon and ribavirin. The patients were treatment in routine practice settings. Data on the study population and on adverse clinical and virologic effects were compiled during the treatment period and during follow up.

RESULTS: One thousand and fifty seven patients were included, 405 (38%) were treated with BOC and 652 (62%) with TVR. Of this total, 30% (n = 319) were TN and the remaining were TE: 28% (n = 298) relapsers, 12% (n = 123) partial responders (PR), 25% (n = 260) null-responders (NR) and for 5% (n = 57) with prior response unknown. The rate of sustained virologic response (SVR) by intention-to-treatment (ITT) was greater in those treated with TVR (65%) than in those treated with BOC (52%) (P < 0.0001), whereas by modified intention-to-treatment (mITT) no were found significant differences. By degree of fibrosis, 56% of patients were F4 and the highest SVR rates were recorded in the non-F4 patients, both TN and TE. In the analysis by groups, the TN patients treated with TVR by ITT showed a higher SVR (P = 0.005). However, by mITT there were no significant differences between BOC and TVR. In the multivariate analysis by mITT, the significant SVR factors were relapsers, IL28B CC and non-F4; the type of treatment (BOC or TVR) was not significant. The lowest SVR values were presented by the F4-NR patients, treated with BOC (46%) or with TVR (45%). 28% of the patients interrupted the treatment, mainly by non-viral response (51%): this outcome was more frequent in the TE than in the TN patients (57% vs 40%, P = 0.01). With respect to severe haematological disorders, neutropaenia was more likely to affect the patients treated with BOC (33% vs 20%, P≤ 0.0001), and thrombocytopaenia and anaemia, the F4 patients (P = 0.000, P = 0.025, respectively).

CONCLUSION: In a real clinical practice setting with a high proportion of patients with advanced fibrosis, effectiveness of first-generation PIs was high except for NR patients, with similar SVR rates being achieved by BOC and TVR.

Uptake and utilization of directly acting antiviral medications for hepatitis C infection in U.S. veterans

New drugs therapies have revolutionized the treatment of hepatitis C virus (HCV) infection. The objectives of this study were to evaluate uptake and utilization of boceprevir and telaprevir in the Department of Veterans Affairs (VA). We evaluated whether therapies conformed to response-guided protocols, whether they replaced standard interferon plus ribavirin treatment, and whether IL-28B was used to guide treatment. We performed an administrative data-based analysis of all patients receiving pharmacologic treatment for HCV in VA from October 2009 to July 2013. There were 12 737 new HCV prescriptions in VA during this time, with 5564 boceprevir or telaprevir prescriptions (44%) and 7173 prescriptions (56%) written for standard interferon plus ribavirin treatment. Prescriptions for the new treatments heavily favoured boceprevir vs telaprevir (83% vs 17%). Sixty-two percent (62%) of boceprevir-treated patients completed their minimum-specified protocol, while 69.2% of telaprevir-treated patients completed their minimum-specified protocol. From October 2010 to July 2012, 4090 patients had an IL-28B test; less than 16% of these tests guided subsequent HCV prescriptions. Uptake of boceprevir and telaprevir was rapid; the number of patients initiating treatment approximately doubled in the period after their introduction. While new prescriptions favor boceprevir or telaprevir over standard interferon plus ribavirin therapy, there appears to still be a strong role of interferon plus ribavirin in treating HCV patients. This work can inform our understanding of how other new effective HCV therapies will be used, their diffusion, and the timing of their diffusion in actual clinical practice.

Should NS5A inhibitors serve as the scaffold for all-oral anti-HCV combination therapies?

Chronic hepatitis C virus (HCV) infection represents a global health problem that affects up to 130–150 million people worldwide. The HCV treatment landscape has been transformed recently by the introduction of direct-acting antiviral (DAA) agents that target viral proteins, including the NS3 protease, the NS5B polymerase, and the NS5A protein. Treatment with multiple DAAs in combination has been shown to result in high rates of sustained virologic response, without the need for pegylated interferon, and a shorter duration of therapy compared with interferon-based regimens; however, the optimal combination of DAAs has yet to be determined. The class of NS5A inhibitors has picomolar potency with pangenotypic activity, and recent clinical studies have shown these inhibitors to be an important component of DAA combination regimens. This review discusses the rational design of an optimal anti-HCV DAA cocktail, with a focus on the role of NS5A in the HCV life cycle, the attributes of the NS5A class of inhibitors, and the potential for NS5A inhibitors to act as a scaffold for DAA-only treatment regimens.

Treatment patterns, health care resource utilization, and costs in U.S. patients diagnosed with chronic hepatitis C infection who received telaprevir or boceprevir

BACKGROUND

Chronic hepatitis C (CHC) is associated with substantial morbidity and mortality, with the future burden of disease predicted to significantly increase. The recent addition of 2 direct-acting antiviral (DAA) protease inhibitors, telaprevir and boceprevir, to peginterferon alfa (PEG) and ribavirin (RBV) therapy has been shown to significantly improve sustained virologic response rates and thus has become standard of care. While the efficacy and safety of DAAs has been assessed in the clinical trial setting, less is known about real-world use of these new therapies.

OBJECTIVES

To (a) evaluate the treatment patterns, health care utilization, and costs of CHC patients receiving DAA-based therapies in the United States using a retrospective analysis of a large administrative claims database and (b) evaluate factors associated with therapy noncompletion using multivariable analyses.

METHODS

Adult patients with ≥ 1 claim for CHC and a prescription filled for boceprevir or telaprevir were selected from a de-identified U.S.-based claims database. The date of the first fill for a DAA after May 13, 2011 (date of first DAA availability) was defined as the index date, and patients were categorized into either the telaprevir or boceprevir cohort. Patients were required to have continuous eligibility and no claims for hepatitis B during the 6 months before (baseline) and 12 months following (study period) the index date. Baseline characteristics and study period treatment patterns, health care utilization, and costs were described. Factors associated with therapy noncompletion were examined using multivariable logistic regression, and adjusted health care costs were compared between the DAA cohorts using multivariable analyses.

RESULTS

A total of 871 telaprevir and 284 boceprevir patients were identified. DAA patients were aged 54 years on average and more often were male (60%, n = 688). Approximately 25% (n = 216) of telaprevir and 18% (n = 52) of boceprevir patients had cirrhosis, and 9% (n = 82) of telaprevir and 7% (n = 20) of boceprevir patients had decompensated cirrhosis at baseline. Less than 1% (n = 9) of patients were HIV co-infected. Approximately 54% (n = 470) of telaprevir and 74% (n = 210) of boceprevir patients did not complete the minimum duration of therapy as per the prescribing information (telaprevir: 12 weeks of triple + 12 weeks of dual; boceprevir: 3 weeks of lead-in + 24 weeks of triple). In multivariable analyses, females (vs. males) and patients taking boceprevir (vs. telaprevir) were more likely to not complete therapy (P = 0.011). CHC patients experienced high medical and drug-related resource utilization. Telaprevir patients had numerically higher study period unadjusted medical (boceprevir: $16,927; telaprevir: $19,519) and drug costs (boceprevir: $59,953; telaprevir: $76,497) than boceprevir patients; however, after adjusting for baseline characteristics, only drug costs remained significantly different (P  less than  0.001). 

CONCLUSIONS

These results indicate that a large proportion of CHC patients receiving telaprevir or boceprevir did not complete minimum duration of therapy as per the prescribing information. CHC patients on a DAA regimen also experienced high resource utilization and high medical and drug costs.

Ribavirin dose reduction during telaprevir/ribavirin/peg-interferon therapy overcomes the effect of the ITPA gene polymorphism

Treatment success of chronic hepatitis C virus genotype 1 infection has improved with the advent of telaprevir plus peg-interferon/ribavirin triple combination therapy. However, the effect of inosine triphosphatase (ITPA) polymorphism on dose reduction during triple therapy, especially during the postmarketing phase, has not been sufficiently evaluated. We analysed 273 patients with genotype 1 infection who were treated with triple therapy and assessed the effect of the ITPA polymorphism on dose reduction. ITPA and IFNL4 SNP genotypes were determined by the Invader assay. A stepwise multivariate regression analysis was performed to identify factors associated with outcome of the therapy. The overall sustained viral response (SVR) rate 12 weeks after the end of therapy was 80.2% (219/273). Decline of haemoglobin was significantly faster, and ribavirin was more extensively reduced in patients with ITPA SNP rs1127354 genotype CC than CA/AA. Extensive reduction of ribavirin resulted in mild reduction of telaprevir and peg-interferon, but no significant increase in viral breakthrough. Although the amount of telaprevir given was slightly higher in CA/AA patients, the total dose of peg-interferon and the SVR rate did not differ between the two groups. Multivariate analysis showed that IFNL4 but not ITPA SNP genotype, platelet count and peg-interferon adherence were significantly associated with outcome of therapy. Postmarketing-phase triple therapy resulted in a high SVR rate in spite of extensive ribavirin dose reduction in a diverse patient population, indicating the importance of treatment continuation and appropriate management of adverse events.

Prevalence and treatment of chronic hepatitis C virus infection in the US Department of Veterans Affairs

Chronic hepatitis C virus (HCV) is the most common blood-borne pathogen in the United States. HCV disproportionately affects Veterans Affairs (VA) health-care users: 174,302 HCV-infected veterans were in VA care in 2013, making the VA the world's largest HCV care provider. This systematic review identified 546 articles related to HCV in the VA. After assessment by 2 independent reviewers, 28 articles describing prevalence and treatment of HCV in VA users ultimately met inclusion criteria. Most VA patients currently living with HCV infection were born between 1945 and 1965 and were infected with HCV between 1970 and 1990. To prevent HCV-related complications such as cirrhosis, hepatocellular carcinoma, and death, medical personnel must identify and treat HCV. However, antiviral therapy has historically been limited by medication side effects, contraindications, and patient acceptance. Although treatment initiation rates are higher in the VA than in the general United States, only 23% of VA HCV patients have received treatment and, of those, only a minority were cured. Recent development of more effective and tolerable antiviral agents represents a major pharmacological breakthrough. Eradication of HCV is theoretically possible for the majority of HCV patients for the first time, although new barriers, such as high drug costs, may limit future uptake.

Cost-effectiveness of sofosbuvir plus ribavirin with or without pegylated interferon for the treatment of chronic hepatitis C in Italy

OBJECTIVE

Across Italy up to 7.3% of the population is infected with hepatitis C virus (HCV), with long-term complications resulting in high medical costs and significant morbidity and mortality. Current treatment options have limitations due to side effects, interferon intolerability and ineligibility, long treatment durations and low sustained virological response (SVR) rates, especially for the most severe patients). Sofosbuvir is the first nucleotide polymerase inhibitor with pan-genotypic activity. Sofosbuvir, administered with ribavirin (RBV) and with or without pegylated interferon (PEG-INF), resulted in >90% SVR across treatment-naïve (TN) genotype (GT) 1-6 patients. It is also the first treatment option for patients that are unsuitable for interferon (UI). This analysis evaluates the cost - effectiveness of sofosbuvir for GTs 1-6 in Italy.

RESEARCH DESIGN AND METHODS

A Markov model followed a cohort of 10,000 patients until they reached 80 years old. Approximately 20% of naïve and 30% of experienced patients initiated treatment at the cirrhosis stage. Comparators included PEG-INF + RBV for all GTs and plus telaprevir or boceprevir for GT1, or no treatment. Costs and outcomes were discounted at 3% and the cost perspective was that of the National Health Service in Italy.

RESULTS

Sofosbuvir was cost-effective with incremental cost-effectiveness ratios (ICERs) below €40,000/QALY in all patient populations, particularly in cirrhotic patients. The exception was for a mixed cohort of GT2 TN patients where the ICER was €68,500/QALY and for a cirrhotic cohort of GT4/5/6 where the ICER was €68,434/QALY. Nevertheless, the prevalence of HCV in this patient population is expected to be low. Results were robust to sensitivity analysis.

CONCLUSIONS

Sofosbuvir-based regimens are cost-effective in Italy, particular for the most severe patients. The interferon-free regimens are a real treatment option for UI patients. The high cure rates of this breakthrough treatment are expected to substantially reduce the burden of HCV in Italy.

Primary results from the cervical dystonia patient registry for observation of onabotulinumtoxina efficacy (CD PROBE)

BACKGROUND

The Cervical Dystonia Patient Registry for Observation of OnabotulinumtoxinA Efficacy (CD PROBE; NCT00836017) is a prospective, observational, multicenter, real-world registry designed to assess the safety, effectiveness, and treatment utilization following multiple treatments of onabotulinumtoxinA.

METHODS

Subjects were naïve to botulinum toxin, new to practice, or had not received toxin in ≥ 16 weeks if in a clinical trial. Dosages and treatment intervals varied due to the real-world design. Descriptive and inferential statistics evaluated changes over 3 treatments.

RESULTS

1046 subjects enrolled. Subjects were 74.4% female, 63.5% toxin-naïve, mean age 58.0 ± 14.7 years. The mean dose over 2481 treatment sessions was 189. 8 ± 87.1U, with average treatment intervals of 14.6 and 15.1 weeks. The mean Toronto Western Spasmodic Torticollis Rating Scale Total score in subjects who completed all assessments (n=479) decreased from 39.2 at baseline to 27.1 at final visit (P<.0001). A high percentage of physicians reported improvement in Clinician Global Impression of Change after initial assessment; this significantly increased at final assessment (n=479, 91.2% vs 95.0%; P<.0001). Similarly, a high percentage of subjects reported improvement in Patient Global Impression of Change after initial assessment, which significantly increased at final assessment (n=470, 83.0% vs 91.7%; P<.0001). Significant reductions in all Cervical Dystonia Impact Profile-58 scores were observed (n=407). Overall, 26.2% of subjects reported adverse events, including muscular weakness (7.0%) and dysphagia (6.4%).

CONCLUSIONS

Results indicate robust improvement in clinical ratings and excellent tolerability following onabotulinumtoxinA treatment of CD.

Predictors of early treatment discontinuation in a cohort of patients treated with boceprevir-based therapy for hepatitis C infection

In this real-world cohort, 49% of patients stopped boceprevir-based hepatitis C therapy early, with only 20% stopping due to treatment futility. Having more comorbidities was significantly associated with early discontinuation. Tolerability of boceprevir-based regimens may be substantially worse than reported in clinical trials, particularly for patients with comorbidities.

Comparative effectiveness of the hepatitis C virus protease inhibitors boceprevir and telaprevir in a large U.S. cohort

BACKGROUND

Limited data exist on the effectiveness of boceprevir and telaprevir in routine practice.

AIM

To assess the comparative effectiveness of boceprevir and telaprevir regimens.

METHODS

In this observational, intent-to-treat cohort analysis of hepatitis C genotype 1-infected veterans initiated on peginterferon/ribavirin and boceprevir (n = 661) or telaprevir (n = 198), we determined sustained virological response (SVR), treatment discontinuation rates and adverse haematological events. Inverse probability-of-treatment weighting (IPTW) was used to estimate the effect of one drug over the other, with matched pairs and unweighted logistic regression on the entire cohort for comparison.

RESULTS

Of 835 veterans, SVR occurred in 50% and 52% receiving boceprevir- and telaprevir-based treatment, respectively (P = 0.72). No significant differences occurred among subgroups: cirrhotics (37% vs. 39%, P = 0.94), null responders (23% vs. 18%, P = 0.81), partial responders (39% vs. 58%, P = 0.15) and relapsers (60% vs. 77%, P = 0.11). Early discontinuation rates for boceprevir and telaprevir, respectively, were 31% and 28% by week 24 (P = 0.46) and 54% and 45% by 48 weeks (in those completing at least 28 weeks) (P = 0.14). Choice of telaprevir over boceprevir was significantly associated with SVR in multivariate models (IPTW OR: 1.57, 95% CI: 1.10-2.25, P = 0.01; matched-pairs OR: 1.91, 95% CI: 1.23-3.00, P = 0.004; unweighted OR: 1.50 95% CI: 1.05-2.14, P = 0.02). Rates of haematological adverse events in boceprevir- and telaprevir-treated patients were as follows: anaemia 59% vs. 51%, P = 0.30, thrombocytopenia 41% vs. 48%, P = 0.26, neutropenia 41% vs. 27%, P = 0.04.

CONCLUSIONS

Sustained virological response was more likely with telaprevir-based regimens compared with boceprevir-based regimens in routine medical practice, after accounting for patient differences. Early discontinuation and haematological events, however, were similar.

Management of anemia induced by triple therapy in patients with chronic hepatitis C: challenges, opportunities and recommendations

The addition of protease inhibitors, boceprevir or telaprevir, to peginterferon+ribavirin (PegIFN/RBV) increases the frequency as well as the severity, and hence, clinical relevance of anemia, which has now become one of the major complications associated with triple therapy. Most significant factors associated with anemia in patients receiving triple therapy include older age, lower body mass index (BMI), advanced fibrosis, and lower baseline hemoglobin. The variability in inosine triphosphate pyrophosphatase (ITPA) gene, which encodes a protein that hydrolyses inosine triphosphate (ITP), has been identified as an essential genetic factor for anemia both in dual and triple therapy. The correct management of anemia is based on anticipation, characterization and therapeutic management. Basically, anemia can be characterized in 3 types: ferropenic (mostly in fertile women), thalassemic type hemolytic anemia, and anemia from chronic processes. Functional deficit of iron should also be excluded in patients with normal ferritin and lower saturation of transferrin. Ribavirin dose reduction and epoetin, sequentially, are indicated in the management of anemia. Epoetin non-response can be caused by lack of time, type of anemia, functional iron deficit or erythropoietin resistance. In the transplantation setting, adding a protease inhibitor to PegIFN/RBV results in a significant increase in the incidence and severity of anemia and, as a consequence, a greater need for epoetin, transfusions, and ribavirin dose reductions. Packed red cell transfusions are utilized when hemoglobin decreases to less than 7.5g/dl and/or there are clinical symptoms and/or there is no response to other therapeutic measures.