130319 Edanz Gunma 2

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130319 Edanz Gunma 2

  1. 1. Reading strategies:Abstracts and the main text Gunma University 19 March 2013 Jeff Robens, PhD Senior Editor
  2. 2. Today’s presentation … Abstracts and literature search Scanning the main text for specific information
  3. 3. Who’s hungry?First impressions are important!
  4. 4. Section 1Reading strategies: Abstracts
  5. 5. Reading strategies: Abstracts Reading abstracts Relevance of Importance of Validity of the the aims the results conclusions First impression of the paper Judge the writing style
  6. 6. Reading strategies: Abstracts Reading abstracts What are the 5 parts of an abstract? Background Aims Methods Results Conclusions
  7. 7. Reading strategies: Abstracts Structured abstractImmunotherapy using slow-cycling tumor cells prolonged overall survival of tumor-bearing miceBackgroundDespite considerable progress in the development of anticancer therapies, there is still a high mortality rate caused by cancerrelapse and metastasis. Dormant or slow-cycling residual tumor cells are thought to be a source of tumor relapse and metastasis,and are therefore an obstacle to therapy. In this study, we assessed the drug resistance of tumor cells in mice, and investigatedwhether vaccination could promote survival.MethodsThe mouse colon carcinoma cell line CT-26 was treated with 5-fluorouracil to assess its sensitivity to drug treatment. Mice withcolon tumors were immunized with inactivated slow-cycling CT-26 cells to estimate the efficacy of this vaccine.ResultsWe identified a small population of slow-cycling tumor cells in the mouse colon carcinoma CT-26 cell line, which was resistant toconventional chemotherapy. To inhibit tumor recurrence and metastasis more effectively, treatments that selectively target theslow-cycling tumor cells should be developed to complement conventional therapies. We found that drug-treated, slow-cyclingtumor cells induced a more intense immune response in vitro. Moreover, vaccination with inactivated slow-cycling tumor cellscaused a reduction in tumor volume and prolonged the overall survival of tumor-bearing mice.ConclusionsThese findings suggest that targeting of slow-cycling tumor cells application using immunotherapy is a possible treatment tocomplement traditional antitumor therapy. Sun et al. (2012). BMC Medicine 10:172.
  8. 8. Reading strategies: Abstracts Structured abstractImmunotherapy using slow-cycling tumor cells prolonged overall survival of tumor-bearing miceBackgroundDespite considerable progress in the development of anticancer therapies, there is still a high mortality rate caused by cancerrelapse and metastasis. Dormant or slow-cycling residual tumor cells are thought to be a source of tumor relapse and metastasis,and are therefore an obstacle to therapy. In this study, we assessed the drug resistance of tumor cells in mice, and investigatedwhether vaccination could promote survival.MethodsThe mouse colon carcinoma cell line CT-26 was treated with 5-fluorouracil to assess its sensitivity to drug treatment. Mice withcolon tumors were immunized with inactivated slow-cycling CT-26 cells to estimate the efficacy of this vaccine.ResultsWe identified a small population of slow-cycling tumor cells in the mouse colon carcinoma CT-26 cell line, which was resistant toconventional chemotherapy. To inhibit tumor recurrence and metastasis more effectively, treatments that selectively target theslow-cycling tumor cells should be developed to complement conventional therapies. We found that drug-treated, slow-cyclingtumor cells induced a more intense immune response in vitro. Moreover, vaccination with inactivated slow-cycling tumor cellscaused a reduction in tumor volume and prolonged the overall survival of tumor-bearing mice.ConclusionsThese findings suggest that targeting of slow-cycling tumor cells application using immunotherapy is a possible treatment tocomplement traditional antitumor therapy. Sun et al. (2012). BMC Medicine 10:172.
  9. 9. Reading strategies: Abstracts Unstructured abstract Differential DNA Methylation Status Between Human Preadipocytes and Mature Adipocytes Obesity is a multifactorial disease resulting from interactions between susceptibility genes, psychosocial, and environmental factors. However, it is becoming evident that interindividual differences in obesity susceptibility depend also on epigenetic factors, although the mechanisms have not been fully elucidated. We have undertaken a genome- wide analysis of DNA methylation of human preadipocytes and mature adipocytes to examine the differences in methylation between them. We found hypomethylation occurring in 2,701 genes and hypermethylation in 1,070 genes after differentiation. Meanwhile, Gene Ontology analysis and Ingenuity Pathway Analysis showed many significant gene functions and pathways with altered methylation status after adipocyte differentiation. In addition, Signal-Net analysis showed that tumor necrosis factor-α, mitogen-activated protein kinase, and interleukin-8 were important to the formation of this network. Our results suggest that DNA methylation mechanisms may be involved in regulating the differentiation process of human preadipocytes. Zhu et al. (2012) Cell Biochem Biophys 63:1‒15.
  10. 10. Reading strategies: Abstracts Unstructured abstractObesity is a multifactorial disease resulting from interactions between susceptibility genes,psychosocial, and environmental factors. However, it is becoming evident thatinterindividual differences in obesity susceptibility depend also on epigenetic factors, Backgroundalthough the mechanisms have not been fully elucidated.We have undertaken a genome-wide analysis of DNA methylation of human preadipocytesand mature adipocytes to examine the differences in methylation between them. MethodsWe found hypomethylation occurring in 2,701 genes and hypermethylation in 1,070 genesafter differentiation. Meanwhile, Gene Ontology analysis and Ingenuity Pathway Analysisshowed many significant gene functions and pathways with altered methylation status afteradipocyte differentiation. In addition, Signal-Net analysis showed that tumor necrosis Resultsfactor-α, mitogen-activated protein kinase, and interleukin-8 were important to theformation of this network.Our results suggest that DNA methylation mechanisms may be involved in regulating thedifferentiation process of human preadipocytes. Conclusion Zhu et al. (2012) Cell Biochem Biophys 63:1‒15.
  11. 11. Reading strategies: Abstracts Reading an abstract Obesity is a multifactorial disease resulting from interactions between susceptibility genes, psychosocial, and environmental factors. However, it is becoming evident that interindividual differences in obesity susceptibility depend also on epigenetic factors, although the mechanisms have not been fully elucidated. We have undertaken a genome-wide analysis of DNA methylation of human preadipocytes and mature adipocytes to examine the differences in methylation between them. We found hypomethylation occurring in 2,701 genes and hypermethylation in 1,070 genes after differentiation. Meanwhile, Gene Ontology analysis and Ingenuity Pathway Analysis showed many significant gene functions and pathways with altered methylation status after adipocyte differentiation. In addition, Signal-Net analysis showed that tumor necrosis factor-α, mitogen-activated protein kinase, and interleukin-8 were important to the formation of this network. Our results suggest that DNA methylation mechanisms may be involved in regulating the differentiation process of human preadipocytes. Zhu et al. (2012) Cell Biochem Biophys 63:1‒15.
  12. 12. Reading strategies: Abstracts Finding information Two points for quickly finding information: Location Where can you find it? Key words Which words to look for?
  13. 13. Reading strategies: Abstracts Unstructured abstract Five-year outcomes in living donor kidney transplants with a positive crossmatch Renal transplant candidates with high levels of donor-specific anti-HLA antibodies have low transplantation rates and high mortality rates on dialysis. Using desensitization protocols, good short-term outcomes are possible in “positive crossmatch kidney transplants (+XMKTx)”, but long- term outcome data are lacking. The aim of the current study was to determine actual 5-year graft outcomes of +XMKTx. We compared graft survival and the functional and histologic status of 102 +XMKTx to 204 −XMKTx matched for age and sex. Actual 5-year death-censored graft survival was lower in the +XMKTx group (70.7% vs. 88.0%, p < 0.01) and chronic injury (glomerulopathy) was present in 54.5% of surviving grafts. Graft survival was higher in recipients with antibody against donor class I only compared with antibody against class II (either alone or in combination with class I) (85.3% vs. 62.6%, p = 0.05) and was similar to −XMKTx (85.3 vs. 88.0%, p = 0.64). Renal function and proteinuria ranged across a wide spectrum in all groups reflecting the different histological findings at 5 years. We conclude that when compared to −XMKTx, +XMKTx have inferior outcomes at 5 years, however, almost half of the surviving grafts do not have glomerulopathy and avoiding antibodies against donor class II may improve outcomes. Key words - objectives: aim, examined, evaluated, studied, investigated Key words – results: showed, identified, found, stronger, higher, lower Key words – conclusions: conclusion, summary Bentall et al. Am J Transplant. 2013;13:76–85.
  14. 14. Reading strategies: Abstracts Structured abstract Identification of new susceptibility loci for osteoarthritis (arcOGEN): a genome-wide association studyBackground:Osteoarthritis is the most common form of arthritis worldwide and is a major cause of pain and disability in elderly people…Osteoarthritis has a strong genetic component but the success of previous genetic studies has been restricted due toinsufficient sample sizes and phenotype heterogeneity.Methods:We undertook a large genome-wide association study (GWAS) in 7410 unrelated and retrospectively and prospectivelyselected patients with severe osteoarthritis in the arcOGEN study… All patients and controls were of European descent.Findings:We identified five genome-wide significant loci (binomial test p≤5·0×10−8) for association with osteoarthritis and three locijust below this threshold. The strongest association was on chromosome 3 with rs6976 (odds ratio 1·12 [95% CI 1·08—1·16];p=7·24×10−11), which is in perfect linkage disequilibrium with rs11177. This SNP encodes a missense polymorphism withinthe nucleostemin-encoding gene GNL3. Levels of nucleostemin were raised in chondrocytes from patients with osteoarthritisin functional studies. Other significant loci were on chromosome 9 close to ASTN2, chromosome 6 between FILIP1 andSENP6… All risk variants were common in frequency and exerted small effectsInterpretation:Our findings provide insight into the genetics of arthritis and identify new pathways that might be amenable to futuretherapeutic intervention. Key words - objectives: aim, examined, evaluated, studied, investigated Key words – results: showed, identified, found, stronger, higher, lower Key words – conclusions: conclusion, summary arcOGEN Consortium & arcOGEN Collaborators. Lancet 2012;380:815–823.
  15. 15. Reading strategies: Abstracts Abstract exercises
  16. 16. Reading strategies: Scanning abstracts Abstracts exercise You are interested in finding novel treatments for triple negative breast cancer Search PubMed for: phase II treatment triple negative breast cancer From the titles, you have identified five potential recent papers Now scan through these five abstracts and determine which one discusses each question
  17. 17. Reading strategies: Scanning abstracts Abstracts exercise Which paper has the largest sample size of TNBC patients? Location? Beginning of the results Key words? Numbers, triple negative, TNBC
  18. 18. Reading strategies: Scanning abstracts Abstracts exercise Which paper has the largest sample size of TNBC patients? Between April 2007 and July 2009, 51 patients were Abstract 1 accrued… Twenty-one of the 51 subjects had triple- negative breast cancer. Abstract 2 Twenty-five patients were enrolled. Abstract 3 Twenty-nine TNLABC patients were treated… A total of 57 women (median age, 53 y) were enrolled… Abstract 4 …9 had triple negative BC (TNBC). Eleven patients, including 6 patients with triple negative Abstract 5 breast cancer, were enrolled.
  19. 19. Reading strategies: Scanning abstracts Abstracts exercise Which paper has the highest pCR/CR for TNBC patients? Location? Results Key words? pCR/CR, triple negative, TNBC
  20. 20. Reading strategies: Scanning abstracts Abstracts exercise Which paper has the highest pCR/CR for TNBC patients? The pCR rate among patients with triple-negative breast Abstract 1 cancer was 19% Abstract 2 The overall response (CR + PR) rate was 4%. Abstract 3 …there were 10 patients (34.48%) with a pathologic CR… Abstract 4 Four of 9 (44%) patients with TNBC achieved pCR. Abstract 5 There were no responses…
  21. 21. Reading strategies: Structuring an Abstracts abstract exercise In some randomized trials comparing revascularization strategies for patients with diabetes, coronary-artery bypass grafting (CABG) has had a better outcome thanBackground percutaneous coronary intervention (PCI). We sought to discover whether aggressive medical therapy and the use of drug-eluting stents could alter the revascularization approach for patients with diabetes and multivessel coronary artery disease. In this randomized trial, we assigned patients with diabetes and multivessel coronary artery disease to undergo either PCI with drug-eluting stents or CABG. The patients were Methods followed for a minimum of 2 years (median among survivors, 3.8 years)… The primary outcome measure was a composite of death from any cause, nonfatal myocardial infarction, or nonfatal stroke. From 2005 through 2010, we enrolled 1900 patients at 140 international centers. The patients mean age was 63.1±9.1 years, 29% were women, and 83% had three-vessel disease. The primary outcome occurred more frequently in the PCI group (P=0.005), with Results 5-year rates of 26.6% in the PCI group and 18.7% in the CABG group… Stroke was more frequent in the CABG group, with 5-year rates of 2.4% in the PCI group and 5.2% in the CABG group (P=0.03). For patients with diabetes and advanced coronary artery disease, CABG was superior toConclusions PCI in that it significantly reduced rates of death and myocardial infarction, with a higher rate of stroke.
  22. 22. Section 2Reading strategies: Main text
  23. 23. Reading strategies: Main text Introduction General Specific Aims
  24. 24. Reading strategies: Introduction – Main text identifying objectivesInduction therapy with autologous mesenchymal stem cells in living-related kidney transplants: a randomized controlled trialInduction therapy, routinely implemented in organ transplant procedures, consists of biologic agents to block earlyimmune activation.1- 2 For kidney transplants, lymphodepletion with antithymocyte globulin (ATG) or alemtuzumab hascontributed to reducing acute rejection episodes and improving early graft function but remains associated with toxiceffects, cytomegalovirus reactivation, and posttransplant lymphoproliferative disease.3- 5 Targeting interleukin 2-(IL-2)receptor α chain on activated T lymphocytes can reduce acute rejection episodes in kidney transplant when combinedwith standard immunosuppression.2Novel induction immunosuppressive protocols with increased efficacy and minimal adverse effects are desirable.Appealing are the immunoregulatory properties of bone marrow–derived mesenchymal stem cells (MSCs), whichrepresent a nonhematopoietic cell population that can differentiate into mesenchymal tissues (ie, bone, cartilage, orfat).3 They inhibit T-cell proliferation, monocyte differentiation to dendritic cells, modulate B-cell functions, andsuppress natural killer cytotoxic effects.5 Thus, MSCs offer new therapeutic opportunities to prevent transplantrejection.6 Le Blanc et al7 first reported the striking clinical response to haploidentical MSCs in a case of severe,treatment-resistant grade IV acute graft-vs-host disease. A multicenter phase 2 trial for steroid-resistant, severe acutegraft-vs-host disease confirmed this observation, while showing no adverse effects after MSC infusion.8 Mesenchymalstem cells obtained from either HLA-identical siblings, haploidentical, or HLA-mismatched third-party donors weresimilarly effective.8 Our study aimed at examining the effect of autologous MSC infusion as an alternative to anti-IL-2receptor antibody for induction therapy in adults undergoing living-related donor kidney transplants. Key words - objectives: aim, examined, evaluated, studied, investigated Tan et al. JAMA 2012;307:1169–1177.
  25. 25. Reading strategies: Main text Methods Multiple methods = New methods Established methodsseparate subheadings described in detail can be cited What they did Materials/subjects General techniques Method order Specific techniques Statistics
  26. 26. Reading strategies: Methods – identifying Main text techniques and patients What was the dosage and administration route? Figure 1. HCV RNA Levels in Groups A and B. Panel A shows HCV RNA levels over time in the patients in group A, who received the NS5A replication complex inhibitor daclatasvir and the NS3 protease inhibitor asunaprevir alone for 24 weeks… Lok et al. New Engl J Med. 2012;366:216–224.
  27. 27. Reading strategies: Methods – identifying Main text techniques and patients Preliminary study of two antiviral agents for hepatitis C genotype 1 Methods Patients Where to look for dosage Study Oversight and administration route Study Design of the drugs? Efficacy Assessments Safety Assessments Viral Breakthrough, Relapse, and Resistance Monitoring End Points Statistical Analysis Lok et al. New Engl J Med. 2012;366:216–224.
  28. 28. Reading strategies: Methods – identifying Main text techniques and patients Preliminary study of two antiviral agents for hepatitis C genotype 1 Methods Study Design This was an open-label, proof-of-concept, phase 2a study. Eligible patients were randomly assigned, in a 1:1 ratio, to receive daclatasvir and asunaprevir for 24 weeks (group A) or to receive daclatasvir, asunaprevir, peginterferon alfa-2a (Pegasys, Roche), and ribavirin (Copegus, Roche) for 24 weeks (group B) (see Fig. 1 in the Supplementary Appendix, available at NEJM.org). Daclatasvir was administered orally at a dose of 60 mg once daily, and asunaprevir was administered orally at a dose of 600 mg twice daily. No dose reductions of daclatasvir or asunaprevir were permitted. Patients in group B also received 180 μg per week of peginterferon alfa-2a, administered subcutaneously, and ribavirin, administered orally twice daily, with doses determined according to body weight (1000 mg daily in patients with body weight of <75 kg, and 1200 mg daily in patients with body weight of ≥75 kg). Randomization was stratified according to HCV subtype (1a or 1b), with no more than two patients with genotype 1b enrolled in each treatment group. Patients in group A were eligible to have peginterferon alfa-2a and ribavirin added to their regimens for up to 48 weeks in the event of viral breakthrough Key words: daclatasvir & asunaprevir Lok et al. New Engl J Med. 2012;366:216–224.
  29. 29. Reading strategies: Methods – identifying Main text techniques and patients Preliminary study of two antiviral agents for hepatitis C genotype 1 Methods Study Design This was an open-label, proof-of-concept, phase 2a study. Eligible patients were randomly assigned, in a 1:1 ratio, to receive daclatasvir and asunaprevir for 24 weeks (group A) or to receive daclatasvir, asunaprevir, peginterferon alfa-2a (Pegasys, Roche), and ribavirin (Copegus, Roche) for 24 weeks (group B) (see Fig. 1 in the Supplementary Appendix, available at NEJM.org). Daclatasvir was administered orally at a dose of 60 mg once daily, and asunaprevir was administered orally at a dose of 600 mg twice daily. No dose reductions of daclatasvir or asunaprevir were permitted. Patients in group B also received 180 μg per week of peginterferon alfa-2a, administered subcutaneously, and ribavirin, administered orally twice daily, with doses determined according to body weight (1000 mg daily in patients with body weight of <75 kg, and 1200 mg daily in patients with body weight of ≥75 kg). Randomization was stratified according to HCV subtype (1a or 1b), with no more than two patients with genotype 1b enrolled in each treatment group. Patients in group A were eligible to have peginterferon alfa-2a and ribavirin added to their regimens for up to 48 weeks in the event of viral breakthrough Lok et al. New Engl J Med. 2012;366:216–224.
  30. 30. Reading strategies: Main text Results What they found Order of results is logical, key finding first Each subsection corresponds to one figure Factually describe the results
  31. 31. Reading strategies: Results – Detailed Main text description of figures Viral breakthrough occurred with which genotype of HCV? Figure 1. HCV RNA Levels in Groups A and B. Panel A shows HCV RNA levels over time in the patients in group A, who received the NS5A replication complex inhibitor daclatasvir and the NS3 protease inhibitor asunaprevir alone for 24 weeks… Lok et al. New Engl J Med. 2012;366:216–224.
  32. 32. Reading strategies: Results – detailed Main text description of figures Resistance Patients Safety Virologic ResponseRESULTS FIGURES Patients Table 1: Baseline demongraphic characteristics of the patients and the disease Figure 1: HCV RNA levels in Groups A and B Virologic Response Table 2: Virologic response during and after treatment Resistance Safety Table 3: Adverse events during the treatment period Where to find which genotypes were involved in the viral breakthrough?
  33. 33. Reading strategies: Results – detailed Main text description of figuresRESULTS Virologic Response Group A HCV RNA levels in the patients in group A declined rapidly after the initiation of treatment (Figure 1A). At week 2, the median decrease in HCV RNA from baseline was 5.1 log10 IU per milliliter, and seven patients (64%) had undetectable HCV RNA at week 4 (rapid virologic response). Four patients (36%) had a sustained virologic response at 12 weeks after the end of the treatment period, and all four also had a sustained virologic response at week 24 after treatment (Table 2). Three of these patients also had a sustained virologic response at week 48 after treatment; the fourth had HCV RNA of less than 25 IU per milliliter at week 48 after treatment and undetectable HCV RNA 43 days later. Viral relapse occurred in one patient (with HCV genotype 1a) at week 4 after treatment. This patient had had undetectable HCV RNA at week 4 during the treatment period, and the levels had remained undetectable through week 24 (end of treatment). An analysis of baseline samples revealed a preexisting variant conferring resistance to asunaprevir (see below). Viral breakthrough occurred in six patients (55%), all with HCV genotype 1a, as early as week 3 and as late as week 12. Key words: viral breakthrough & genotype
  34. 34. Reading strategies: Results – detailed Main text description of figuresRESULTS Virologic Response Group A HCV RNA levels in the patients in group A declined rapidly after the initiation of treatment (Figure 1A). At week 2, the median decrease in HCV RNA from baseline was 5.1 log10 IU per milliliter, and seven patients (64%) had undetectable HCV RNA at week 4 (rapid virologic response). Four patients (36%) had a sustained virologic response at 12 weeks after the end of the treatment period, and all four also had a sustained virologic response at week 24 after treatment (Table 2). Three of these patients also had a sustained virologic response at week 48 after treatment; the fourth had HCV RNA of less than 25 IU per milliliter at week 48 after treatment and undetectable HCV RNA 43 days later. Viral relapse occurred in one patient (with HCV genotype 1a) at week 4 after treatment. This patient had had undetectable HCV RNA at week 4 during the treatment period, and the levels had remained undetectable through week 24 (end of treatment). An analysis of baseline samples revealed a preexisting variant conferring resistance to asunaprevir (see below). Viral breakthrough occurred in six patients (55%), all with HCV genotype 1a, as early as week 3 and as late as week 12. Key words: viral breakthrough & genotype
  35. 35. Reading strategies: Main text Discussion Summarize key findings Beginning State major conclusion Interpret results in context Middle of other studies Describe limitations Restate major conclusion End Applications/implications Suggest future work
  36. 36. Discussion – summary Reading strategies: Main text of results and Discussion conclusions In this study, we assessed the effect of coadministration for 24 weeks of two direct-acting antiviral agents with different mechanisms of action, daclatasvir and asunaprevir, alone or with peginterferon1 alfa-2a and ribavirin, in an exploratory cohort of patients with HCV infection, who typically do not have a response to retreatment with peginterferon and ribavirin and are expected to have a poor response to triple therapy with peginterferon and ribavirin plus a protease inhibitor (boceprevir or telaprevir).A total of 90% of the patients carried IL28B genotypes (the rs12979860 SNP CT or TT), which are associated with poor response to peginterferon and ribavirin, and most of the patients had HCV genotype 1a infection. The low rate of sustained virologic response achieved with peginterferon and ribavirin among patients with HCV genotype 1 infection, coupled with high rates of adverse effects, have stimulated the2 development of direct-acting antiviral agents and the study of regimens that exclude peginterferon, ribavirin, or both. Coadministration of daclatasvir and asunaprevir alone in group A initially led to a rapid reduction in HCV RNA, with all 11 patients achieving greater than a 4-log10 decline. Ultimately, 5 patients had undetectable HCV RNA at the end of the treatment period, and 4 had sustained virologic response at weeks 12 and 24 after treatment, establishing proof-of-concept that sustained virologic response can be achieved without peginterferon or ribavirin. Both of the patients in group A who were infected with HCV genotype 1b had sustained virologic response at weeks 12 and 24 after treatment. Six patients in group A (all with HCV genotype 1a infection)3 had viral breakthrough. Previous studies have also shown that some patients receiving combinations of direct-acting antiviral agents without interferon have had viral breakthrough. In our study, viral breakthrough correlated with baseline HCV RNA levels (Table 1 in the Supplementary Appendix) and did not appear to be associated with pharmacokinetic findings at day 14 (data not shown). Although there were only 2 patients with HCV genotype 1b infection in group A, the observation that both of the patients had a sustained virologic response after treatment with two direct-acting antiviral agents alone may reflect a higher resistance barrier for this combination of drugs in patients with HCV genotype 1b infection than in patients with HCV genotype 1a infection. A similar finding of a high rate of sustained virologic response among patients with HCV genotype 1b infection was shown in a pilot study of combination therapy with asunaprevir and daclatasvir in 10 Japanese patients who had HCV genotype 1b infection and who had not had a response to previous therapy with peginterferon and ribavirin. Although all six patients with viral breakthrough initially had a response to the addition of peginterferon and ribavirin as rescue therapy, most ultimately had therapeutic failure during or after the4 treatment period, which was consistent with their previous lack of response to those agents. The high frequency of resistance to two classes of drugs that was seen in patients with HCV genotype 1a infection who were treated with direct-acting antiviral agents alone suggests that studies of combinations of direct-acting antiviral agents without peginterferon and ribavirin in patients with HCV genotype 1a infection should proceed carefully. In contrast to group A, no viral breakthrough occurred in patients in group B, who were receiving quadruple therapy. All 10 patients in group B achieved a sustained virologic response at week 12 after5 treatment and all but 1 had a sustained virologic response at week 24 after treatment. The inclusion of peginterferon alfa-2a and ribavirin with daclatasvir and asunaprevir provided sufficient antiviral activity to suppress the emergence of resistance, an observation that is consistent with in vitro data showing a synergism of interferon and ribavirin with both direct-acting antiviral agents. Retreatment with peginterferon and ribavirin in patients who have not had a previous response to those drugs is generally unsuccessful, and even triple therapy with peginterferon, ribavirin, and telaprevir in these patients produced rates of sustained virologic response of approximately 30% at week 24 after treatment. Gane and colleagues found that a combination of two direct-acting antiviral agents can suppress HCV RNA in patients who have not had a response to peginterferon and ribavirin, but the treatment with the combination of direct-acting antiviral agents was limited to 13 days and was followed immediately by treatment with peginterferon and ribavirin, thus preventing the assessment of sustained response to the direct-acting antiviral agents only. Among the 14 patients who had a sustained virologic response at week 12 after treatment, an HCV RNA level of less than 25 IU per milliliter was detected in 1 patient at week 24 after treatment and in 26 other patients at week 48 after treatment. All 3 patients had undetectable HCV RNA on retesting. These data indicate that late relapse is unlikely to occur in patients who have a sustained virologic response with combination direct-acting antiviral agents at week 12 after treatment. The most common adverse event was diarrhea, which was mild or moderate in all cases. Grade 3 or 4 neutropenia occurred in six patients, all of whom were receiving peginterferon and ribavirin in7 addition to the two direct-acting antiviral agents. No grade 3 or 4 events related to hemoglobin levels or platelet counts were observed. Transient elevations of alanine aminotransferase levels were observed in six patients; these elevations were not associated with clinically significant increases in bilirubin level. In addition, we did not find any association between these elevations and a reduction in HCV RNA levels, viral breakthrough, or pharmacokinetic findings at day 14. Similar elevations of alanine aminotransferase levels were observed in a separate dose-ranging study of asunaprevir in combination with peginterferon and ribavirin, and a lower dose of asunaprevir was selected for ongoing and future studies. In conclusion, therapy with daclatasvir, asunaprevir, peginterferon alfa-2a, and ribavirin for 24 weeks provided a high rate of sustained virologic response in patients with HCV genotype 1 infection who8 had not had a response to previous therapy with peginterferon and ribavirin. The response in some patients to the combination of daclatasvir and asunaprevir alone showed proof-of-concept that a sustained virologic response can be achieved without peginterferon and ribavirin therapy. Both patients with HCV genotype 1b infection who were treated with the combination of direct-acting antiviral agents alone had a sustained virologic response. In contrast, the response rate was low in patients with genotype 1a infection. Overall, these results suggest that further research with combinations of direct-acting antiviral agents, with or without peginterferon and ribavirin, is warranted. Future studies should evaluate other combinations of direct-acting antiviral agents with high potency and nonoverlapping resistance profiles and investigate treatments tailored to specific characteristics of the patient and the virus.
  37. 37. Discussion – summary Reading strategies: Main text of results andDiscussion conclusionsIn this study, we assessed the effect of coadministration for 24 weeks of two direct-acting antiviral agents with different mechanisms of action, daclatasvir and asunaprevir, alone or with peginterferonalfa-2a and ribavirin, in an exploratory cohort of patients with HCV infection, who typically do not have a response to retreatment with peginterferon and ribavirin and are expected to have a poorresponse to triple therapy with peginterferon and ribavirin plus a protease inhibitor (boceprevir or telaprevir).A total of 90% of the patients carried IL28B genotypes (the rs12979860 SNP CT or TT), whichare associated with poor response to peginterferon and ribavirin, and most of the patients had HCV genotype 1a infection.The low rate of sustained virologic response achieved with peginterferon and ribavirin among patients with HCV genotype 1 infection, coupled with high rates of adverse effects, have stimulated thedevelopment of direct-acting antiviral agents and the study of regimens that exclude peginterferon, ribavirin, or both. Coadministration of daclatasvir and asunaprevir alone in group A initially led to arapid reduction in HCV RNA, with all 11 patients achieving greater than a 4-log10 decline. Ultimately, 5 patients had undetectable HCV RNA at the end of the treatment period, and 4 had sustained virologicresponse at weeks 12 and 24 after treatment, establishing proof-of-concept that sustained virologic response can be achieved without peginterferon or ribavirin.Both of the patients in group A who were infected with HCV genotype 1b had sustained virologic response at weeks 12 and 24 after treatment. Six patients in group A (all with HCV genotype 1a infection)had viral breakthrough. Previous studies have also shown that some patients receiving combinations of direct-acting antiviral agents without interferon have had viral breakthrough. In our study, viralbreakthrough correlated with baseline HCV RNA levels (Table 1 in the Supplementary Appendix) and did not appear to be associated with pharmacokinetic findings at day 14 (data not shown). Althoughthere were only 2 patients with HCV genotype 1b infection in group A, the observation that both of the patients had a sustained virologic response after treatment with two direct-acting antiviral agentsalone may reflect a higher resistance barrier for this combination of drugs in patients with HCV genotype 1b infection than in patients with HCV genotype 1a infection. A similar finding of a high rate ofsustained virologic response among patients with HCV genotype 1b infection was shown in a pilot study of combination therapy with asunaprevir and daclatasvir in 10 Japanese patients who had HCVgenotype 1b infection and who had not had a response to previous therapy with peginterferon and ribavirin.Although all six patients with viral breakthrough initially had a response to the addition of peginterferon and ribavirin as rescue therapy, most ultimately had therapeutic failure during or after thetreatment period, which was consistent with their previous lack of response to those agents. The high frequency of resistance to two classes of drugs that was seen in patients with HCV genotype 1ainfection who were treated with direct-acting antiviral agents alone suggests that studies of combinations of direct-acting antiviral agents without peginterferon and ribavirin in patients with HCVgenotype 1a infection should proceed carefully.In contrast to group A, no viral breakthrough occurred in patients in group B, who were receiving quadruple therapy. All 10 patients in group B achieved a sustained virologic response at week 12 aftertreatment and all but 1 had a sustained virologic response at week 24 after treatment. The inclusion of peginterferon alfa-2a and ribavirin with daclatasvir and asunaprevir provided sufficient antiviralactivity to suppress the emergence of resistance, an observation that is consistent with in vitro data showing a synergism of interferon and ribavirin with both direct-acting antiviral agents. Retreatmentwith peginterferon and ribavirin in patients who have not had a previous response to those drugs is generally unsuccessful, and even triple therapy with peginterferon, ribavirin, and telaprevir in thesepatients produced rates of sustained virologic response of approximately 30% at week 24 after treatment. Gane and colleagues found that a combination of two direct-acting antiviral agents can suppressHCV RNA in patients who have not had a response to peginterferon and ribavirin, but the treatment with the combination of direct-acting antiviral agents was limited to 13 days and was followedimmediately by treatment with peginterferon and ribavirin, thus preventing the assessment of sustained response to the direct-acting antiviral agents only.Among the 14 patients who had a sustained virologic response at week 12 after treatment, an HCV RNA level of less than 25 IU per milliliter was detected in 1 patient at week 24 after treatment and in 2other patients at week 48 after treatment. All 3 patients had undetectable HCV RNA on retesting. These data indicate that late relapse is unlikely to occur in patients who have a sustained virologicresponse with combination direct-acting antiviral agents at week 12 after treatment.The most common adverse event was diarrhea, which was mild or moderate in all cases. Grade 3 or 4 neutropenia occurred in six patients, all of whom were receiving peginterferon and ribavirin inaddition to the two direct-acting antiviral agents. No grade 3 or 4 events related to hemoglobin levels or platelet counts were observed. Transient elevations of alanine aminotransferase levels wereobserved in six patients; these elevations were not associated with clinically significant increases in bilirubin level. In addition, we did not find any association between these elevations and a reduction inHCV RNA levels, viral breakthrough, or pharmacokinetic findings at day 14. Similar elevations of alanine aminotransferase levels were observed in a separate dose-ranging study of asunaprevir incombination with peginterferon and ribavirin, and a lower dose of asunaprevir was selected for ongoing and future studies.In conclusion, therapy with daclatasvir, asunaprevir, peginterferon alfa-2a, and ribavirin for 24 weeks provided a high rate of sustained virologic response in patients with HCV genotype 1 infection whohad not had a response to previous therapy with peginterferon and ribavirin. The response in some patients to the combination of daclatasvir and asunaprevir alone showed proof-of-concept that asustained virologic response can be achieved without peginterferon and ribavirin therapy. Both patients with HCV genotype 1b infection who were treated with the combination of direct-acting antiviralagents alone had a sustained virologic response. In contrast, the response rate was low in patients with genotype 1a infection. Overall, these results suggest that further research with combinations ofdirect-acting antiviral agents, with or without peginterferon and ribavirin, is warranted. Future studies should evaluate other combinations of direct-acting antiviral agents with high potency andnonoverlapping resistance profiles and investigate treatments tailored to specific characteristics of the patient and the virus.
  38. 38. Reading strategies: Discussion – Main text summary of results1 In this study, we assessed the effect of coadministration for 24 weeks of two direct-acting antiviral agents with different mechanisms of action, daclatasvir and asunaprevir, alone or with peginterferon alfa-2a and ribavirin, in an exploratory cohort of patients with HCV infection, who typically do not have a response to retreatment with peginterferon and ribavirin and are expected to have a poor response to triple therapy with peginterferon and ribavirin plus a protease inhibitor (boceprevir or telaprevir). A total of 90% of the patients carried IL28B genotypes (the rs12979860 SNP CT or TT), which are associated with poor response to peginterferon and ribavirin, and most of the patients had HCV genotype 1a infection.2 The low rate of sustained virologic response achieved with peginterferon and ribavirin among patients with HCV genotype 1 infection, coupled with high rates of adverse effects, have stimulated the development of direct-acting antiviral agents and the study of regimens that exclude peginterferon, ribavirin, or both. Coadministration of daclatasvir and asunaprevir alone in group A initially led to a rapid reduction in HCV RNA, with all 11 patients achieving greater than a 4-log10 decline. Ultimately, 5 patients had undetectable HCV RNA at the end of the treatment period, and 4 had sustained virologic response at weeks 12 and 24 after treatment, establishing proof-of-concept that sustained virologic response can be achieved without peginterferon or ribavirin. What is the key finding and the main conclusion of this study?
  39. 39. Reading strategies: Discussion – Main text summary of results AimsIn this study, we assessed the effect of coadministration for 24 weeks of two direct-acting antiviralagents with different mechanisms of action, daclatasvir and asunaprevir, alone or with peginterferonalfa-2a and ribavirin, in an exploratory cohort of patients with HCV infection, who typically do nothave a response to retreatment with peginterferon and ribavirin and are expected to have a poorresponse to triple therapy with peginterferon and ribavirin plus a protease inhibitor (boceprevir ortelaprevir). A total of 90% of the patients carried IL28B genotypes (the rs12979860 SNP CT or TT),which are associated with poor response to peginterferon and ribavirin, and most of the patients hadHCV genotype 1a infection.The low rate of sustained virologic response achieved with peginterferon and ribavirin among patientswith HCV genotype 1 infection, coupled with high rates of adverse effects, have stimulated thedevelopment of direct-acting antiviral agents and the study of regimens that exclude peginterferon,ribavirin, or both. Coadministration of daclatasvir and asunaprevir alone in group A initially led to arapid reduction in HCV RNA, with all 11 patients achieving greater than a 4-log10 decline. Ultimately, 5patients had undetectable HCV RNA at the end of the treatment period, and 4 had sustained virologicresponse at weeks 12 and 24 after treatment, establishing proof-of-concept that sustained virologicresponse can be achieved without peginterferon or ribavirin. What is the key finding?
  40. 40. Reading strategies: Discussion – Main text summary of results AimsIn this study, we assessed the effect of coadministration for 24 weeks of two direct-acting antiviralagents with different mechanisms of action, daclatasvir and asunaprevir, alone or with peginterferonalfa-2a and ribavirin, in an exploratory cohort of patients with HCV infection, who typically do nothave a response to retreatment with peginterferon and ribavirin and are expected to have a poorresponse to triple therapy with peginterferon and ribavirin plus a protease inhibitor (boceprevir ortelaprevir). A total of 90% of the patients carried IL28B genotypes (the rs12979860 SNP CT or TT),which are associated with poor response to peginterferon and ribavirin, and most of the patients hadHCV genotype 1a infection.The low rate of sustained virologic response achieved with peginterferon and ribavirin among patientswith HCV genotype 1 infection, coupled with high rates of adverse effects, have stimulated the Key findingdevelopment of direct-acting antiviral agents and the study of regimens that exclude peginterferon,ribavirin, or both. Coadministration of daclatasvir and asunaprevir alone in group A initially led to arapid reduction in HCV RNA, with all 11 patients achieving greater than a 4-log10 decline. Ultimately, 5patients had undetectable HCV RNA at the end of the treatment period, and 4 had sustained virologicresponse at weeks 12 and 24 after treatment, establishing proof-of-concept that sustained virologicresponse can be achieved without peginterferon or ribavirin. What is the main conclusion?
  41. 41. Reading strategies: Discussion – Main text summary of results AimsIn this study, we assessed the effect of coadministration for 24 weeks of two direct-acting antiviralagents with different mechanisms of action, daclatasvir and asunaprevir, alone or with peginterferonalfa-2a and ribavirin, in an exploratory cohort of patients with HCV infection, who typically do nothave a response to retreatment with peginterferon and ribavirin and are expected to have a poorresponse to triple therapy with peginterferon and ribavirin plus a protease inhibitor (boceprevir ortelaprevir). A total of 90% of the patients carried IL28B genotypes (the rs12979860 SNP CT or TT),which are associated with poor response to peginterferon and ribavirin, and most of the patients hadHCV genotype 1a infection.The low rate of sustained virologic response achieved with peginterferon and ribavirin among patientswith HCV genotype 1 infection, coupled with high rates of adverse effects, have stimulated the Key findingdevelopment of direct-acting antiviral agents and the study of regimens that exclude peginterferon,ribavirin, or both. Coadministration of daclatasvir and asunaprevir alone in group A initially led to arapid reduction in HCV RNA, with all 11 patients achieving greater than a 4-log10 decline. Ultimately, 5patients had undetectable HCV RNA at the end of the treatment period, and 4 had sustained virologicresponse at weeks 12 and 24 after treatment, establishing proof-of-concept that sustained virologicresponse can be achieved without peginterferon or ribavirin. Main conclusion
  42. 42. Reading strategies: Discussion – conclusions Main text and implications8 In conclusion, therapy with daclatasvir, asunaprevir, peginterferon alfa-2a, and ribavirin for 24 weeks provided a high rate of sustained virologic response in patients with HCV genotype 1 infection who had not had a response to previous therapy with peginterferon and ribavirin. The response in some patients to the combination of daclatasvir and asunaprevir alone showed proof-of-concept that a sustained virologic response can be achieved without peginterferon and ribavirin therapy. Both patients with HCV genotype 1b infection who were treated with the combination of direct-acting antiviral agents alone had a sustained virologic response. In contrast, the response rate was low in patients with genotype 1a infection. Overall, these results suggest that further research with combinations of direct-acting antiviral agents, with or without peginterferon and ribavirin, is warranted. Future studies should evaluate other combinations of direct-acting antiviral agents with high potency and nonoverlapping resistance profiles and investigate treatments tailored to specific characteristics of the patient and the virus. What is the main conclusion of this research?
  43. 43. Reading strategies: Discussion – conclusions Main text and implications MainIn conclusion, therapy with daclatasvir, asunaprevir, peginterferon alfa-2a, and ribavirin for 24 weeks conclusionprovided a high rate of sustained virologic response in patients with HCV genotype 1 infection whohad not had a response to previous therapy with peginterferon and ribavirin. The response in somepatients to the combination of daclatasvir and asunaprevir alone showed proof-of-concept that asustained virologic response can be achieved without peginterferon and ribavirin therapy. Bothpatients with HCV genotype 1b infection who were treated with the combination of direct-actingantiviral agents alone had a sustained virologic response. In contrast, the response rate was low inpatients with genotype 1a infection. Overall, these results suggest that further research withcombinations of direct-acting antiviral agents, with or without peginterferon and ribavirin, iswarranted. Future studies should evaluate other combinations of direct-acting antiviral agents withhigh potency and nonoverlapping resistance profiles and investigate treatments tailored to specificcharacteristics of the patient and the virus. What is the main implication of this research?
  44. 44. Reading strategies: Discussion – conclusions Main text and implications MainIn conclusion, therapy with daclatasvir, asunaprevir, peginterferon alfa-2a, and ribavirin for 24 weeks conclusionprovided a high rate of sustained virologic response in patients with HCV genotype 1 infection whohad not had a response to previous therapy with peginterferon and ribavirin. The response in somepatients to the combination of daclatasvir and asunaprevir alone showed proof-of-concept that asustained virologic response can be achieved without peginterferon and ribavirin therapy. Bothpatients with HCV genotype 1b infection who were treated with the combination of direct-actingantiviral agents alone had a sustained virologic response. In contrast, the response rate was low inpatients with genotype 1a infection. Overall, these results suggest that further research withcombinations of direct-acting antiviral agents, with or without peginterferon and ribavirin, iswarranted. Future studies should evaluate other combinations of direct-acting antiviral agents withhigh potency and nonoverlapping resistance profiles and investigate treatments tailored to specificcharacteristics of the patient and the virus. Implications
  45. 45. Reading strategies Advanced reading strategies Read Title and Abstract first During your literature search Read last paragraph of Introduction for hypothesis/objectives Read Figures Refer to Results and Methods for specific information Read Discussion for conclusions and implications
  46. 46. Any questions? Thank you! edanzediting.co.jp/gunma2013 Download and further reading @JournalAdvisor Follow us on Twitter facebook.com/JournalAdvisor Like us on Facebookwww.edanzediting.co.jp

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