Adjusted estimate of the prevalence of hepatitis delta virus in 25 countries and territories

BACKGROUND & AIMS

Hepatitis delta virus (HDV) is a satellite RNA virus that requires the hepatitis B virus (HBV) for assembly and propagation. Individuals infected with HDV progress to advanced liver disease faster than HBV-monoinfected individuals. Recent studies have estimated the global prevalence of anti-HDV antibodies among the HBV-infected population to be 5-15%. This study aimed to better understand HDV prevalence at the population level in 25 countries/territories.

METHODS

We conducted a literature review to determine the prevalence of anti-HDV and HDV RNA in hepatitis B surface antigen (HBsAg)-positive individuals in 25 countries/territories. Virtual meetings were held with experts from each setting to discuss the findings and collect unpublished data. Data were weighted for patient segments and regional heterogeneity to estimate the prevalence in the HBV-infected population. The findings were then combined with The Polaris Observatory HBV data to estimate the anti-HDV and HDV RNA prevalence in each country/territory at the population level.

RESULTS

After adjusting for geographical distribution, disease stage and special populations, the anti-HDV prevalence among the HBsAg+ population changed from the literature estimate in 19 countries. The highest anti-HDV prevalence was 60.1% in Mongolia. Once adjusted for the size of the HBsAg+ population and HDV RNA positivity rate, China had the highest absolute number of HDV RNA+ cases.

CONCLUSIONS

We found substantially lower HDV prevalence than previously reported, as prior meta-analyses primarily focused on studies conducted in groups/regions that have a higher probability of HBV infection: tertiary care centers, specific risk groups or geographical regions. There is large uncertainty in HDV prevalence estimates. The implementation of reflex testing would improve estimates, while also allowing earlier linkage to care for HDV RNA+ individuals. The logistical and economic burden of reflex testing on the health system would be limited, as only HBsAg+ cases would be screened.

IMPACT AND IMPLICATIONS

There is a great deal of uncertainty surrounding the prevalence of hepatitis delta virus among people living with hepatitis B virus at the population level. In this study, we aimed to better understand the burden in 25 countries and territories, to refine techniques that can be used in future analyses. We found a lower prevalence in the majority of places studied than had been previously reported. These data can help inform policy makers on the need to screen people living with hepatitis B virus to find those coinfected with hepatitis delta virus and at high risk of progression, while also highlighting the pitfalls that other researchers have often fallen into.

Selinexor, bortezomib, and dexamethasone versus bortezomib and dexamethasone in previously treated multiple myeloma: Outcomes by cytogenetic risk

In the phase 3 BOSTON study, patients with multiple myeloma (MM) after 1-3 prior regimens were randomized to once-weekly selinexor (an oral inhibitor of exportin 1 [XPO1]) plus bortezomib-dexamethasone (XVd) or twice-weekly bortezomib-dexamethasone (Vd). Compared with Vd, XVd was associated with significant improvements in median progression-free survival (PFS), overall response rate (ORR), and lower rates of peripheral neuropathy, with trends in overall survival (OS) favoring XVd. In BOSTON, 141 (35.1%) patients had MM with high-risk (presence of del[17p], t[4;14], t[14;16], or ≥4 copies of amp1q21) cytogenetics (XVd, n = 70; Vd, n = 71), and 261 (64.9%) exhibited standard-risk cytogenetics (XVd, n = 125; Vd, n = 136). Among patients with high-risk MM, median PFS was 12.91 months for XVd and 8.61 months for Vd (HR, 0.73 [95% CI, (0.4673, 1.1406)], p = 0.082), and ORRs were 78.6% and 57.7%, respectively (OR 2.68; p = 0.004). In the standard-risk subgroup, median PFS was 16.62 months for XVd and 9.46 months for Vd (HR 0.61; p = 0.004), and ORRs were 75.2% and 64.7%, respectively (OR 1.65; p = 0.033). The safety profiles of XVd and Vd in both subgroups were consistent with the overall population. These data suggest that selinexor can confer benefits to patients with MM regardless of cytogenetic risk. ClinicalTrials.gov identifier: NCT03110562.

The effect of cardiorehabilitation on the quality of life by congestive heart failure patients

Funding Acknowledgements

Type of funding sources: None.

Introduction

To examine selected parameters of quality of life in patients with cardiac failure after cardiorehabilitation in outpatient and inpatient form and to compare the effect with each other.

Methods and methodology: The survey included 64 respondents without age restrictions with chronic heart failure NYHA I. - III. after undergoing inpatient or outpatient cardiorehabilitation, polymorbid, oncology and psychiatric patients were excluded. The questionnaire with 20 questions focused on 12 quality of life domains. Statistical processing: t-test, ANOVA, Chi-square test, Spearman correlation coefficient (p <0.05).

Results

35 men (54.7%) and 29 women (45.3%) were included, with a mean age of 58.07 years, with a mean duration of CHF treatment of 3.99 years, subgroups (internal 25, cardiology 21 and institute 18 probands) did not differ in age. We found that cardiorehabilitation has a positive effect on the quality of life of patients with CHF, if it is associated with social support, appropriate education and meets the conditions of a comprehensive approach. Patients rated their quality of life better compared to their quality of life a year ago. Outpatients are more satisfied with their health than patients in inpatient treatment, patients with a more severe manifestation of CHF have a greater anxiety from physical activity and therefore less motivation to move. All patients expressed dissatisfaction with their sex lives. Patients in outpatient treatment experience more depression. There were no differences between the subgroups in the evaluation of the degree of education by the nurse and the effect of the exercise on the subjective condition. All subgroups perceived the other person"s help more valuable than medical help. Patients from inpatient treatment have been more motivated to change their lifestyle on their own initiative and through the influence of information from healthcare professionals.

Conclusion

Comprehensive cardiovascular rehabilitation of patients with heart failure improves many of the prognostic indicators of heart failure, reduces mortality and the frequency of rehospitalizations, reduces treatment costs, improves quality of life. nevertheless, rehabilitation programs for chronic heart failure are being promoted only very slowly. The reason may be the absence of standard procedures, as well as organizational, economic and personnel demands.

Effect of age and frailty on the efficacy and tolerability of once-weekly selinexor, bortezomib, and dexamethasone in previously treated multiple myeloma

Elderly and frail patients with multiple myeloma (MM) are more vulnerable to the toxicity of combination therapies, often resulting in treatment modifications and suboptimal outcomes. The phase 3 BOSTON study showed that once-weekly selinexor and bortezomib with low-dose dexamethasone (XVd) improved PFS and ORR compared with standard twice-weekly bortezomib and moderate-dose dexamethasone (Vd) in patients with previously treated MM. This is a retrospective subgroup analysis of the multicenter, prospective, randomized BOSTON trial. Post hoc analyses were performed to compare XVd versus Vd safety and efficacy according to age and frailty status (<65 and ≥65 years, nonfrail and frail). Patients ≥65 years with XVd had higher ORR (OR 1.77, p = .024), ≥VGPR (OR, 1.68, p = .027), PFS (HR 0.55, p = .002), and improved OS (HR 0.63, p = .030), compared with Vd. In frail patients, XVd was associated with a trend towards better PFS (HR 0.69, p = .08) and OS (HR 0.62, p = .062). Significant improvements were also observed in patients <65 (ORR and TTNT) and nonfrail patients (PFS, ORR, ≥VGPR, and TTNT). Patients treated with XVd had a lower incidence of grade ≥ 2 peripheral neuropathy in ≥65 year-old (22% vs. 37%; p = .0060) and frail patients (15% vs. 44%; p = .0002). Grade ≥3 TEAEs were not observed more often in older compared to younger patients, nor in frail compared to nonfrail patients. XVd is safe and effective in patients <65 and ≥65 and in nonfrail and frail patients with previously treated MM.

Survival among older patients with previously treated multiple myeloma treated with selinexor, bortezomib, and dexamethasone (XVd) in the BOSTON study

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Background: Multiple myeloma (MM) typically affects older populations, which are more vulnerable to toxicity with anti-MM treatments. These patients (pts) have significant morbidity and mortality, resulting in a need for dose modifications or alternative suboptimal treatment options. Significant improvements were observed in the BOSTON study with XVd vs Vd in median progression-free survival (PFS), overall response rate (ORR), and rates of peripheral neuropathy (PN); median overall survival (OS) trended in favor of XVd. Methods: The phase 3 randomized BOSTON trial (NCT03110562) is a controlled, open-label study of once weekly XVd vs. twice weekly standard Vd in pts with MM and 1-3 prior treatment regimens. We performed post-hoc analyses to compare survival benefits in pts ≥65 vs < 65 years of age. Results: The BOSTON study enrolled a total of 402 pts between June 2017 and February 2019 that were randomized into XVd or Vd arms. The numbers of pts treated with XVd or Vd who were ≥65 were 109/132 and 86/75 who were < 65, respectively. Baseline characteristics were similar by age although pts ≥65 years were less likely to have received ASCT than those < 65 years (48.4% vs. 25.3%). Median PFS was prolonged with XVd compared with Vd, across both age groups: ≥65 (HR, 0.55 [95% CI, 0.37-0.83] P = 0.002) and < 65, (HR, 0. 74 [95% CI, 0.49-1.11], P = 0.07). Vd was associated with a lower ORR (64.4%) than treatment with XVd (76.1%) (OR, 1.77 [95% CI, 1.00-3.11], P = 0.024) in pts ≥65, while the ORR in those < 65 was 76.7% with XVd and 58.7% (OR, 2.33 [95% CI, 1.18-4.59], P = 0.007) with Vd. As of Jan 2021, the median OS for the overall population was not reached for both arms (HR = 0.86; p = 0.193), with 61 and 75 deaths in the XVd and Vd arms, respectively. Median OS was not reached in pts ≥65 with XVd and was 28.6 months with Vd (HR = 0.60; 95% CI, 0.38-0.94; p = 0.012), while there was no difference in the OS for pts < 65 (HR = 1.52; 95% CI, 0.86-2.68; p = 0.926). Pts ≥65 had a lower incidence of death with XVd as compared to Vd (29 vs 56) and there were 32 deaths with XVd and 19 with Vd in pts < 65. Grade ≥3 treatment-emergent adverse events were not observed more often in older compared to younger pts. Amongst pts ≥65, PN of any grade was lower with XVd (32.1%) compared to Vd (46.5%); (OR 0.57 [95% CI 0.34-0.97], p = 0.017), including a lower incidence of grade ≥3 PN (XVd 4.6% vs. Vd 11.6%). Pts < 65 followed a similar trend of PN AEs of any grade: XVd, 32.6%; Vd, 48.0% (OR 0.42 [95% CI 0.21-0.82], p = 0.006). Conclusions: In an older patient population with a poor prognosis, XVd was associated with a significant survival benefit, improved PFS and OR with reduced PN, and requires relatively short and infrequent clinic visits. XVd may be a simple, effective regimen for pts ≥65 years of age. Clinical trial information: NCT03110562.

Effects of refractory status to lenalidomide on safety and efficacy of selinexor, bortezomib, and dexamethasone (XVd) versus bortezomib and dexamethasone (Vd) in patients with previously treated multiple myeloma

8024

Background: Lenalidomide (LEN) is typically a frontline therapy for newly diagnosed MM. Patients (pts) with MM refractory to LEN are less likely to repond to other IMiDs and represent a signification area of unmet medical need. In the BOSTON study in the ITT population, XVd was associated with significant improvements in median progression-free survival (PFS), overall response rate (ORR), and rates of peripheral neuropathy, with trends in overall survival (OS) favoring XVd. Methods: The BOSTON trial (NCT03110562) is a Phase 3 randomized, controlled, open-label study of once weekly XVd vs twice weekly Vd in pts with MM and 1-3 prior therapies. We performed post-hoc analyses on two different subgroups to compare outcomes based on refractory status to LEN and immunomodulatory drug (IMiD) therapy. These post hoc analyses evaluated if PFS, overall response rate (ORR), time to next treatment (TTNT) and safety was influenced by prior treatment with LEN when comparing XVd with Vd. Results: Amongst the 402 pts in BOSTON, 160 had MM refractory to any IMiD (XVd = 74, Vd = 86). Of those, 106 were documented to be refractory to LEN (XVd = 53, Vd = 53) and 296 were not refractory to LEN (XVd = 142, Vd = 154). Baseline characteristics were generally well balanced between subgroups. In these subgroups based on refractory status to IMiD or LEN, median PFS was significantly longer in the XVd arm as compared to Vd (IMiD refractory, 13.9 vs. 8.4 months (mo), p = 0.005; LEN refractory, 10.2 vs. 7.1 mo, p = 0.012; not LEN refractory, 15.4 vs 9.6 mo, p = 0.014). Significant increases in TTNT were observed with XVd treatment in pts that were IMiD refractory (14.8 vs. 10.2 mo, p = 0.003), LEN refractory (13.0 vs. 7.6 mo, p = 0.015), and not refractory to LEN (19.1 vs 12.9 mo, p = 0.005). ORR was improved with XVd compared to Vd regardless of refractory status (IMiD refractory, 68.9% vs 55.8%, p = 0.045; LEN refractory, 67.9% vs. 47.2%, p = 0.016; and not refractory to LEN, 79.6% vs 67.5%, p = 0.010). The most common treatment-emergent AEs for the XVd/Vd arms for all subgroups were thrombocytopenia (66.2/30.6%; 71.7/40.4%; 55.6/22.4%), nausea (48.6/11.8%; 50.9/11.5%; 50.0/9.2%), and fatigue (40.5/20.0%; 45.3/21.2%; 40.8/17.1%) for IMiD, LEN, and not LEN refractory, respectively. Incidence of PN AEs of any grade were reduced compared to pts treated with Vd (IMiD refractory, 27% vs. 42.4%; LEN refractory, 30.2% vs 36.5%; not refractory, LEN 33.1% vs 50.7%). Conclusions: In pts with previously treated MM, PFS, ORR, and TTNT were significantly improved regardless of documented refractory status to any IMiD or to LEN-specifically. These analyses support the use of the XVd combination for pts with disease refractory to LEN and likely to any IMiD. Clinical trial information: NCT03110562.

Effect of prior treatments on selinexor, bortezomib, and dexamethasone in previously treated multiple myeloma

Therapeutic regimens for previously treated multiple myeloma (MM) may not provide prolonged disease control and are often complicated by significant adverse events, including peripheral neuropathy. In patients with previously treated MM in the Phase 3 BOSTON study, once weekly selinexor, once weekly bortezomib, and 40 mg dexamethasone (XVd) demonstrated a significantly longer median progression-free survival (PFS), higher response rates, deeper responses, a trend to improved survival, and reduced incidence and severity of bortezomib-induced peripheral neuropathy when compared with standard twice weekly bortezomib and 80 mg dexamethasone (Vd). The pre-specified analyses described here evaluated the influence of the number of prior lines of therapy, prior treatment with lenalidomide, prior proteasome inhibitor (PI) therapy, prior immunomodulatory drug therapy, and prior autologous stem cell transplant (ASCT) on the efficacy and safety of XVd compared with Vd. In this 1:1 randomized study, enrolled patients were assigned to receive once weekly oral selinexor (100 mg) with once weekly subcutaneous bortezomib (1.3 mg/m2) and 40 mg per week dexamethasone (XVd) versus standard twice weekly bortezomib and 80 mg per week dexamethasone (Vd). XVd significantly improved PFS, overall response rate, time-to-next-treatment, and showed reduced all grade and grade ≥ 2 peripheral neuropathy compared with Vd regardless of prior treatments, but the benefits of XVd over Vd were more pronounced in patients treated earlier in their disease course who had either received only one prior therapy, had never been treated with a PI, or had prior ASCT. Treatment with XVd improved outcomes as compared to Vd regardless of prior therapies as well as manageable and generally reversible adverse events. XVd was associated with clinical benefit and reduced peripheral neuropathy compared to standard Vd in previously treated MM. These results suggest that the once weekly XVd regimen may be optimally administered to patients earlier in their course of disease, as their first bortezomib-containing regimen, and in those relapsing after ASCT.Trial registration: ClinicalTrials.gov (NCT03110562). Registered 12 April 2017. https://clinicaltrials.gov/ct2/show/NCT03110562 .

Erythropoietin as an independent prognostic factor in myelodysplastic syndromes

AIM

To assess the level of erythropoietin (EPO) in blood sera of patients with different subtypes of myelodysplastic syndromes (MDS) from different risk subgroups and to determine its prognostic role.

MATERIALS AND METHODS

EPO was measured by enzyme-linked immunosorbent assay in peripheral blood of 54 patients with different MDS subtypes according to the French-American-British (FAB) classification. The comparison group consisted of 15 healthy individuals. Complete blood count (hemoglobin, leukocyte and platelet levels) was determined and bone marrow cells were characterized morphologically. The overall and leukemia-free survivals were estimated by Kaplan - Meier method.

RESULTS

The level of ЕРО in MDS was reliably higher in comparison with healthy persons (p < 0.01, Mann - Whitney test). No statistically significant difference was found in serum EPO concentration between the groups of patients with low- and high-risk MDS (603.5 pg/ml vs 721.0 pg/ml; p > 0.05). In transfusion-dependent patients, the level of EPO was significantly higher than in other patients, which may be due to increased endogenous EPO secretion resulting from chronic hypoxia. A negative correlation was revealed between EPO level and Hb level as well as between EPO level and percentage of blast cells in bone marrow in high-risk MDS patients but not in patients with less aggressive variants of MDS. Instead, patients with low-risk MDS had a negative relationship between concentrations of EPO and tumor necrosis factor alpha (p = 0.06, Kendall's tau test). No significant difference was found between EPO concentration in cases differing by bone marrow cellularity or the presence of cytogenetic abnormalities. An EPO concentration below 200 pg/ml was a predictor of shorter overall survival in patients with all MDS subtypes (p < 0.05, Mann - Whitney test). In patients with all FAB disease subtypes, there was no relationship between the leukemia-free survival and serum EPO concentration.

CONCLUSION

This study shows that lower serum EPO level may be considered as one of the additional adverse prognostic factors in MDS patients.

Once-per-week selinexor, bortezomib, and dexamethasone versus twice-per-week bortezomib and dexamethasone in patients with multiple myeloma (BOSTON): a randomised, open-label, phase 3 trial

BACKGROUND

Selinexor combined with dexamethasone has shown activity in patients with heavily pre-treated multiple myeloma. In a phase 1b/2 study, the combination of oral selinexor with bortezomib (a proteasome inhibitor) and dexamethasone induced high response rates with low rates of peripheral neuropathy, the main dose-limiting toxicity of bortezomib. We aimed to evaluate the clinical benefit of weekly selinexor, bortezomib, and dexamethasone versus standard bortezomib and dexamethasone in patients with previously treated multiple myeloma.

METHODS

This phase 3, randomised, open-label trial was done at 123 sites in 21 countries. Patients aged 18 years or older, who had multiple myeloma, and who had previously been treated with one to three lines of therapy, including proteasome inhibitors, were randomly allocated (1:1) to receive selinexor (100 mg once per week), bortezomib (1·3 mg/m2 once per week), and dexamethasone (20 mg twice per week), or bortezomib (1·3 mg/m2 twice per week for the first 24 weeks and once per week thereafter) and dexamethasone (20 mg four times per week for the first 24 weeks and twice per week thereafter). Randomisation was done using interactive response technology and stratified by previous proteasome inhibitor therapy, lines of treatment, and multiple myeloma stage. The primary endpoint was progression-free survival in the intention-to-treat population. Patients who received at least one dose of study treatment were included in the safety population. This trial is registered at ClinicalTrials.gov, NCT03110562. The trial is ongoing, with 55 patients remaining on randomised therapy as of Feb 20, 2020.

FINDINGS

Of 457 patients screened for eligibility, 402 were randomly allocated-195 (49%) to the selinexor, bortezomib, and dexamethasone group and 207 (51%) to the bortezomib and dexamethasone group-and the first dose of study medication was given between June 6, 2017, and Feb 5, 2019. Median follow-up durations were 13·2 months [IQR 6·2-19·8] for the selinexor, bortezomib, and dexamethasone group and 16·5 months [9·4-19·8] for the bortezomib and dexamethasone group. Median progression-free survival was 13·93 months (95% CI 11·73-not evaluable) with selinexor, bortezomib, and dexamethasone and 9·46 months (8·11-10·78) with bortezomib and dexamethasone (hazard ratio 0·70 [95% CI 0·53-0·93], p=0·0075). The most frequent grade 3-4 adverse events were thrombocytopenia (77 [39%] of 195 patients in the selinexor, bortezomib, and dexamethasone group vs 35 [17%] of 204 in the bortezomib and dexamethasone group), fatigue (26 [13%] vs two [1%]), anaemia (31 [16%] vs 20 [10%]), and pneumonia (22 [11%] vs 22 [11%]). Peripheral neuropathy of grade 2 or above was less frequent with selinexor, bortezomib, and dexamethasone (41 [21%] patients) than with bortezomib and dexamethasone (70 [34%] patients; odds ratio 0·50 [95% CI 0·32-0·79], p=0·0013). 47 (24%) patients in the selinexor, bortezomib, and dexamethasone group and 62 (30%) in the bortezomib and dexamethasone group died.

INTERPRETATION

A once-per-week regimen of selinexor, bortezomib, and dexamethasone is a novel, effective, and convenient treatment option for patients with multiple myeloma who have received one to three previous lines of therapy.

FUNDING

Karyopharm Therapeutics.

Weekly selinexor, bortezomib, and dexamethasone (SVd) versus twice weekly bortezomib and dexamethasone (Vd) in patients with multiple myeloma (MM) after one to three prior therapies: Initial results of the phase III BOSTON study

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Background: Selinexor is an oral, selective inhibitor of XPO1-mediated nuclear export, leading to the reactivation of tumor suppressor proteins. In a phase 1b/2 study, the combination of once weekly (QW) selinexor with bortezomib and dexamethasone (SVd) was well tolerated with anti-MM activity in patients (pts) with PI-sensitive and PI-refractory disease. While twice weekly (BIW) bortezomib in combination therapy is efficacious, prolonged use is limited due to peripheral neuropathy (PN, 50-60%). The BOSTON study was designed to determine if SVd improves progression free survival (PFS), overall response rates (ORR) and reduces the rate of PN vs Vd. Methods: BOSTON is a global, phase 3, randomized study of QW SVd vs BIW Vd after 1-3 prior anti-MM regimens. The primary endpoint is PFS. Secondary endpoints include ORR, overall survival (OS) and PN (rates and EORTC QLQ-CIPN20 outcomes). Randomization is stratified by treatment with prior PI therapies, number of prior anti-MM regimens (1 vs > 1), and Revised International Staging System (R-ISS; Stage III vs I or II). Following confirmation of progressive disease, pts on Vd could cross over to either: 1) SVd for pts able to tolerate continued bortezomib or 2) selinexor and dexamethasone for pts with bortezomib intolerance. Results:402 pts were enrolled; 195 and 207 to SVd and Vd, respectively. Median age was 67 (range: 38-90). Most (59.6%) pts were > 65 years and 57.1% were male. R-ISS stage at the time of MM diagnosis was III for 18.5% of pts. Baseline characteristics were balanced across the 2 arms. SVd significantly prolonged PFS vs Vd (median 13.93 vs 9.46 months, HR = 0.70, P = 0.0066). SVd was associated with a significantly higher ORR (76.4% vs 62.3%, P = 0.0012). Median OS was not reached on SVd vs 25 months on Vd (P = 0.28). Most frequent treatment-related adverse events (grade ≥3) for SVd vs Vd were thrombocytopenia (35.9% vs 15.2%), fatigue (11.3% vs 0.5%) and nausea (7.7% vs 0%). Clinically important differences were reported on the motor, autonomic and sensory scales on CIPN20. PN rates (grade ≥2) were significantly lower with SVd vs Vd (21.0% vs 34.3%, P = 0.0013). Conclusions: BOSTON is the first phase 3 study to evaluate the clinical benefit of SVd for relapsed/refractory MM. The study met the primary endpoint: once weekly SVd significantly improved PFS and ORR compared to twice weekly Vd. Rates of PN were significantly reduced with numerically fewer deaths on SVd vs Vd. Full dataset will be presented at the meeting. Clinical trial information: NCT03110562 .

Historical epidemiology of hepatitis C virus in select countries-volume 4

Due to the introduction of newer, more efficacious treatment options, there is a pressing need for policy makers and public health officials to develop or adapt national hepatitis C virus (HCV) control strategies to the changing epidemiological landscape. To do so, detailed, country-specific data are needed to characterize the burden of chronic HCV infection. In this study of 17 countries, a literature review of published and unpublished data on HCV prevalence, viraemia, genotype, age and gender distribution, liver transplants and diagnosis and treatment rates was conducted, and inputs were validated by expert consensus in each country. Viraemic prevalence in this study ranged from 0.2% in Hong Kong to 2.4% in Taiwan, while the largest viraemic populations were in Nigeria (2 597 000 cases) and Taiwan (569 000 cases). Diagnosis, treatment and liver transplant rates varied widely across the countries included in this analysis, as did the availability of reliable data. Addressing data gaps will be critical for the development of future strategies to manage and minimize the disease burden of hepatitis C.

The present and future disease burden of hepatitis C virus infections with today's treatment paradigm: Volume 4

Factors influencing the morbidity and mortality associated with viremic hepatitis C virus (HCV) infection change over time and place, making it difficult to compare reported estimates. Models were developed for 17 countries (Bahrain, Bulgaria, Cameroon, Colombia, Croatia, Dominican Republic, Ethiopia, Ghana, Hong Kong, Jordan, Kazakhstan, Malaysia, Morocco, Nigeria, Qatar and Taiwan) to quantify and characterize the viremic population as well as forecast the changes in the infected population and the corresponding disease burden from 2015 to 2030. Model inputs were agreed upon through expert consensus, and a standardized methodology was followed to allow for comparison across countries. The viremic prevalence is expected to remain constant or decline in all but four countries (Ethiopia, Ghana, Jordan and Oman); however, HCV-related morbidity and mortality will increase in all countries except Qatar and Taiwan. In Qatar, the high-treatment rate will contribute to a reduction in total cases and HCV-related morbidity by 2030. In the remaining countries, however, the current treatment paradigm will be insufficient to achieve large reductions in HCV-related morbidity and mortality.

Strategies to manage hepatitis C virus infection disease burden-Volume 4

The hepatitis C virus (HCV) epidemic was forecasted through 2030 for 17 countries in Africa, Asia, Europe, Latin America and the Middle East, and interventions for achieving the Global Health Sector Strategy on viral hepatitis targets-"WHO Targets" (65% reduction in HCV-related deaths, 90% reduction in new infections and 90% of infections diagnosed by 2030) were considered. Scaling up treatment and diagnosis rates over time would be required to achieve these targets in all but one country, even with the introduction of high SVR therapies. The scenarios developed to achieve the WHO Targets in all countries studied assumed the implementation of national policies to prevent new infections and to diagnose current infections through screening.

Liver transplantations in Bulgaria--initial experience

The filed of liver transplantation (LT) continues to evolve and is highly effective therapy for many patients with acute and chronic liver failure resulting from a variety of causes. Improvement of perioperative care, surgical technique and immunosuppression in recent years has led to its transformation into a safe and routine procedure with steadily improving results. The aim of this paper is to present the initial experience of the transplant team at Military Medical Academy - Sofia, Bulgaria. For the period of April 2007 - August 2014 the team performed 38 liver transplants in 37 patients (one retransplantation). Patients were followed up prospectively and retrospectively. In 36 (95%) patients a graft from a cadaveric donor was used and in two cases--a right liver grafts from live donor. The mean MELD score of the transplanted patients was 17 (9-40). The preferred surgical technique was "piggyback" with preservation of inferior vena cava in 33 (86%) of the cases and classical technique in 3 (8%) patients. The overall complication rate was 48%. Early mortality rate was 13% (5 patients). The overall 1- and 5-year survival is 81% and 77% respectivelly. The setting of a new LT program is a complex process which requires the effort and effective colaboration of a wide range of speciacialists (hepatologists, surgeons, anesthesiologists, psychologists, therapists, coordinators, etc.) and institutions. The good results are function of a proper selection of the donors and the recipients. Living donation is an alternative in the shortage of cadaveric donors.

Species of Enterococcus faecalis associated with free-living rodents

Enterococci from different free-living rodents were isolated and selected. The strains were genotyped and their antibiotic sensitivity and /or resistance, production of lactic acid, urease activity, the presence of enterocin structural genes, plasmid detection, and their binding ability to proteins were determined. Among 24 enterococcal strains, 17 strains were allotted to the species Enterococcus faecalis by tDNA-PCR, 7 strains being not yet identified. Only Enterococcus sp. ES66 possessed the structural genes for the production of enterocins (Ent) A and P. E. faecalis EE61 had the gene for EntL50B. The other isolates were Ent-gene-free. Enterococci were mostly sensitive to antibiotic treatment . The plasmid DNA was detected only in the strain EE97. The average value of lactic acid production reached 896 +/- 90 micromol/L. Most of the strains possessed low ureolytic activity. Enterococci bound very well sub-epithelial proteins, reaching the value of 3 by the particle agglutination assay, especially concerning the heparin, bovine lactoferrin and porcine fibronectin.

Tyrosinase mutants are capable of prodrug activation in transfected nonmelanotic cells

Tyrosinase has been suggested as a prodrug-converting enzyme for the treatment of melanoma. We hypothesized that tyrosinase expression in transfected nonmelanotic cells can be used in a gene therapy paradigm of prodrug activation. To verify our hypothesis, we used the following tyrosinase variants: (a) a full-length human tyrosinase clone (T); (b) a mutant lacking the COOH-terminal cytoplasmic domain (TdeltaC); (c) a mutant lacking the COOH-terminal transmembrane and cytoplasmic domains (TdeltaTC); and (d) a fusion with the eight COOH-terminal amino acids of lysosome-associated membrane protein-1 (TL). Expression of mutant and wild-type tyrosinases was induced by transfection in nontumorigenic human cells of epithelial origin (293HEK, MCF-10A adenoma, and NHDF-Ad human dermal fibroblasts) as well as in tumor cells (9L gliosarcoma, MCF7 adenocarcinoma, and HT-1080 fibrosarcoma). When compared with the wild-type tyrosinase transfectants, truncated mutant expression resulted in higher mRNA levels that paralleled higher enzyme activity of the truncated mutants. Two model tyrosinase prodrugs, hydroxyphenyl-propanol (HPP) and N-acetyl-4-S-cysteaminylphenol (NAcSCAP) inhibited proliferation and caused cell death of transfected cells in a dose-dependent manner. Effects of prodrug treatment were compared for tumorigenic cells and their nontumorigenic counterparts. Two truncated mutants (TdeltaC and TdeltaTC) showed low endogenous cytotoxicity and efficiently suppressed proliferation and induced cytotoxicity in transfected tumor cells in the presence of NAcSCAP. Overall, these results indicate that the developed tyrosinase mutants hold promise as prodrug activation systems for tumoral gene therapy.

Engineering membrane proteins for nuclear medicine: applications for gene therapy and cell tracking

Nuclear imaging techniques such as PET and SPECT imaging are expected to play major roles in evaluating the efficacy of in vivo gene therapy. In particular, the quantification of vector delivery and imaging the efficacy of gene expression are of key interests in testing new treatment paradigms and in designing novel vectors. In this review article we illustrate how nuclear imaging can be used to image novel cell-surface expressed fusion proteins and how this strategy can be used to probe for phenotypic changes in genetically manipulated cells. Since the described approach uses new fusion proteins, typically not present on eukaryotic cells, such "artificial receptors" can be designed to bind radioisotopes currently in clinical use. The described fusion proteins consist of 1) a binding domain such as a peptide based chelator that binds 99mTc oxotechnetate and 2) a membrane anchoring domain. A variety of fusion proteins have been tested so far and the most promising one to date consists of a metallothionein (MT)-derived C-terminal peptide fused to a type II membrane protein markers containing the N-terminal membrane anchoring domain of neutral endopeptidase (PEP). Cell-surface expression of MT in transfected cells has been demonstrated using monoclonal antibodies in vitro. Both in vitro and in vivo transchelation experiments have confirmed expression of 99mTc-binding sites in eukaryotic cells. We expect the described approach to evolve into a useful strategy to "tag" transfected cells with 99mTc and thus assessing efficiency of gene delivery and expression.

Targeting of green fluorescent protein expression to the cell surface

We have previously reported on GPI-anchored fusion proteins that bind radioactive isotopes. We targeted their expression to the cell surface to obtain a marker protein detectable by nuclear and optical imaging (1, 2). Here we suggest a novel approach for targeting a model protein (GFP) to the exoplasmic surface of the plasma membrane. An expression vector (pcPEP-GFP) was constructed containing GFP cDNA fused with the fragment encoding the N-terminal cytoplasmic domain and signal peptide/membrane anchoring domain of the rabbit neutral endopeptidase (PEP-GFP). Flow cytometry showed green fluorescence in 45% of cells transfected with GFP and in 34% of cells transfected with PEP-GFP (24 h after transfection). Fluorescence microscopy of fixed cells stained with rhodaminated anti-GFP antibodies showed positive reaction only in the case of PEP-GFP-transfected cells indicating cell-surface expression. The PEP-GFP fusion protein was identified as a component of the light microsomal and Golgi fractions by immunoblotting.

Novel gliosarcoma cell line expressing green fluorescent protein: A model for quantitative assessment of angiogenesis

Angiogenesis is essential for tumor proliferation and metastasis. The extent of angiogenesis is measured by microvessel density (MVD) which has been identified as an independent prognostic factor for relapse-free survival in cancer patients. Existing methods of MVD assessment measure the microvessel count in the most active area of neovascularization ("hot spots") using antibodies against vascular endothelial antigens. This may produce unreliable results because of tissue volume loss and misshapening during the fixation and dehydration procedures. We report here a genetically engineered 9L cell line constitutively expressing green fluorescent protein that can be visualized using fluorescence microscopy without additional histological staining. The model developed in this study allows for the performance of simple and easy MVD counting, assuming that nonfluorescent "black spots" visible by fluorescence microscopy within the borders of the tumor tissue represent blood vessels. This assumption was confirmed by a comparative study utilizing conventional histological methods, anti-CD31 immunohistology, and Hoechst 33258 dye exclusion. This model is also useful for delineation of the true borders between tumor and normal brain tissue, including microscopic tumor extensions, without multiple histological staining. The suggested model allows quantification of tumor angiogenesis in tissue specimens, thus providing independent prognostic information about tumor growth and regression. It is expected to be most valuable in evaluating the efficacy of anti-angiogenic therapy.

MR imaging of gene delivery to the central nervous system with an artificial vector

PURPOSE

To determine whether gene delivery by means of a synthetic no viral DNA delivery system that is capable of gene transfer can be mapped with magnetic resonance (MR) imaging.

MATERIALS AND METHODS

The DNA delivery system consisted of aminated (poly-L-lysine-conjugated) dextran chains anchored together with a central superparamagnetic core. Three different types of constructs were synthesized that differed in their amino content and, thus, DNA-loading capacity. The model plasmid consisted of complementary DNA encoding for humanized green fluorescent protein. Constructs were tested in cell culture and in vivo in a rat model.

RESULTS

All three constructs were capable of transfecting human cells in culture with transfection efficiencies ranging from 0.3% to 4.1%, which is similar to that of diethylaminoethyl-dextran. MR imaging experiments showed that DNA constructs induced signal intensity changes that co-localized with phosphorus-33-labeled plasmid distribution at autoradiography. After injection of the constructs into the corpus callosum of rats, weak green fluorescent protein expression of neuronal and glial cells could be detected at immunohistologic examination.

CONCLUSION

Dextran-based nonviral DNA delivery systems are capable of transfecting cells and can be visualized with MR imaging.

Design of metal-binding green fluorescent protein variants

Diglycylcysteine motifs bind reduced oxo-compounds of technetium-99m, an important isotope in nuclear imaging. We suggested a system for detecting gene expression employing the effect of oxo[99mTc]technetate (Tc(V)O3+) transchelation and coordination with redox amino acid motifs. DNA fragments encoding diglycylcysteine (GGC) binding motifs were prepared by PCR and positioned downstream from the green fluorescent protein (GFP) cDNA insert. Using a Bluescript (+) vector with the fusion protein positioned under the control of a lac promoter, we obtained several E. coli clones expressing the following GFP fusion peptides: (1) GFP-P1 bearing a 'hydrophilic' C-terminal peptide (LEGGGCEGGC) containing two residues of glutamic acid and C-terminal cysteine (2) GFP-P2 carrying a 'hydrophobic' (LGGGGCGGGCGI) peptide (3) a control GFP fusion peptide with deleted C-terminal portion. Bacterial lysates obtained from the corresponding clones were tested for oxo[99mTc] technetate transchelation from a glucoheptonate complex. We found, using a solid phase assay, that radioactivity associated with protein lysates obtained from clones expressing GFP-P2 fusions were 3-4 fold higher than lysates prepared from a clone expressing a truncated GFP fusion protein lacking the C-terminal GGC motifs. High expression of GFP fusions (5-21% of total protein) was demonstrated by electrophoresis and verified by immunoblotting. Specific association of the isotope with GFP-P2 fusion proteins was detected upon incubation of gels in the presence of [99mTc]glucoheptonate, while no binding of oxo[99mTc]technetate to GFP-P1 was revealed. We demonstrated, by using semi-quantitative autoradiography, that there is a 10-fold higher binding of oxotechnetate to GFP-P2 than to a control GFP fusion protein. The implications of the study for in vivo gene expression imaging are discussed.

MR imaging and scintigraphy of gene expression through melanin induction

PURPOSE

To determine whether an expression vector that encodes for human tyrosinase, the key enzyme in the melanin production pathway, can be used to image gene expression with magnetic resonance (MR) imaging and scintigraphy.

MATERIALS AND METHODS

Mouse fibroblasts and human embryonal kidney cells were transfected with an expression vector that contained a complete complementary DNA sequence that encodes the human tyrosinase gene (pcDNA3tyr). Transfected cells were assayed for messenger RNA presence, melanin staining, and indium-111 binding; scintigraphy and MR imaging were performed.

RESULTS

Transfected cells contained tyrosinase messenger RNA and stained positively for melanin. Transfected cells had a higher In-111 binding capacity than nontransfected cells, a difference readily detectable with scintigraphy. MR imaging showed transfected cells to have markedly higher signal intensity after gene transfer than nontransfected cells.

CONCLUSION

Gene transfer and expression in cell culture can be detected with MR imaging and scintigraphy. The proposed strategy of using an imaging marker gene may have a substantial effect on the noninvasive imaging of gene therapy.