Comparative immunogenicity assessment of biosimilars.

The first anticancer biosimilars have entered clinical use, with many others under clinical development. Like all biologics, biosimilars may elicit unwanted immune responses that can significantly impact clinical efficacy and safety. Head-to-head immunogenicity assessment of biosimilars and their reference biologics should, therefore, be a critical component of a biosimilar's clinical development program. Various bioanalytical platforms may be used to detect and characterize immune responses, each having relative strengths and weaknesses. To fully recognize the clinical relevance of such data, regulators must be able to interpret immunogenicity results in an assay-specific context as well as in perspective of clinical pharmacology, efficacy and safety. Herein, we discuss current challenges imposed by global regulatory requirements for immunogenicity assessment of biosimilars.

On-treatment prediction of sustained response to peginterferon alfa-2a for HBeAg-negative chronic hepatitis B patients.

BACKGROUND & AIMS: We assessed predictors of response in HBeAg-negative chronic hepatitis B patients treated with peginterferon alfa-2a in routine clinical practice. METHODS: Ninety-five HBeAg-negative patients received peginterferonalfa-2a for 48 weeks and were followed-up for 48 weeks post-treatment. Serum HBsAg and HBV DNA levels were monitored during and after therapy with valid commercial assays. Sustained response (SR) was defined as HBV DNA <2000 IU/ml at study week 96. RESULTS: Twenty-two patients (23%) achieved SR and nine (9.5%) lost HBsAg. HBsAg decline was more profound in patients with SR. HBsAg decline ≥10% from baseline to week 24 was significantly associated with SR [81% (17/21) vs 37% (21/57); Odds ratio: 7.286 (2.162-24.552), P = 0.001]. The PARC rule (no decrease in HBsAg and <2 log drop in HBV DNA at week 12) was evaluated in a subset of 47 patients. Among eight patients who fulfilled the PARC rule, none achieved SR. Of the 39 patients who did not fulfil the PARC rule, 24 (62%) had HBsAg decline of ≥10% at week 24 (12 achieved SR) and 15 (38%) had HBsAg decline of <10% (1 achieved SR; negative predictive value: 93%). CONCLUSIONS: In HBeAg-negative chronic hepatitis B patients treated with peginterferon alfa-2a, HBsAg decline >10% at 24 weeks is significantly associated with SR. The combination of the PARC rule and week 24 decline in HBsAg can identify almost two-thirds of patients who are unlikely to achieve SR. Clinicaltrials.gov identifier: NCT01283074.

Final analysis of the international observational S-Collate study of peginterferon alfa-2a in patients with chronic hepatitis B.

BACKGROUND AND AIMS: Sustained off-treatment immune control is achievable in a proportion of patients with chronic hepatitis B treated with peginterferon alfa-2a. We evaluated on-treatment predictors of hepatitis B surface antigen (HBsAg) clearance 3 years after peginterferon alfa-2a treatment and determined the incidence of hepatocellular carcinoma. METHODS: A prospective, international, multicenter, observational study in patients with chronic hepatitis B who have been prescribed peginterferon alfa-2a (40KD) in a real-world setting. The primary endpoint was HBsAg clearance after 3 years' follow-up. RESULTS: The modified intention-to-treat population comprised 844 hepatitis B e antigen (HBeAg)-positive patients (540 [64%] completed 3 years' follow-up), and 872 HBeAg-negative patients (614 [70%] completed 3 years' follow-up). At 3 years' follow-up, HBsAg clearance rates in HBeAg-positive and HBeAg-negative populations, respectively, were 2% (16/844) and 5% (41/872) in the modified intention-to-treat population and 5% [16/328] and 10% [41/394] in those with available data. In HBeAg-positive patients with data, Week 12 HBsAg levels <1500, 1500-20,000, and >20,000 IU/mL were associated with HBsAg clearance rates at 3 years' follow-up of 11%, 1%, and 5%, respectively (Week 24 predictability was similar). In HBeAg-negative patients with available data, a ≥10% decline vs a <10% decline in HBsAg at Week 12 was associated with HBsAg clearance rates of 16% vs 4%. Hepatocellular carcinoma incidence was lower than REACH-B (Risk Estimation for Hepatocellular Carcinoma in Chronic Hepatitis B) model predictions. CONCLUSIONS: Sustained off-treatment immune control is achieved with peginterferon alfa-2a in a real-world setting. HBsAg clearance 3 years after completion of peginterferon alfa-2a can be predicted on the basis of on-treatment HBsAg kinetics.

Drug Discontinuation in Studies Including a Switch From an Originator to a Biosimilar Monoclonal Antibody: A Systematic Literature Review.

PURPOSE: In observational studies of patients switched from stable treatment with an originator monoclonal antibody (mAb) to a biosimilar, higher rates of biosimilar discontinuation versus those observed in blinded switching studies have been reported. Because this observation relates to the real-world setting, it has been suggested that switching outside of clinical trials may be associated with nocebo effects. However, real-world data on drug discontinuation and nocebo effects after switching to mAb biosimilars remain limited. This systematic review collated information from switching studies regarding discontinuation rates of biosimilar mAbs and investigated the subjectivity of reasons for discontinuation to determine the impact of potential nocebo responses. METHODS: MEDLINE (via PubMed), EMBASE, Cochrane Library, and abstract databases of selected congresses were screened for reports of mAb switching studies with a minimum post-switch follow-up ≥6 months and accessible information on discontinuation rates. FINDINGS: A total of 14 observational studies were included, all of which involved a switch to CT-P13. Ten interventional studies involving a switch to other biosimilar mAbs were excluded from the analysis because nocebo effects relate to the observational setting only. Eleven studies (78.6%) reported biosimilar discontinuation rates that were higher than expected based on data pertaining to long-term use of the originator infliximab and clinical trials involving a switch to CT-P13 (>10% per year; range, 12.2%-28.2%). Eight studies attributed a proportion of discontinuations to subjective disease worsening or subjective adverse events. Subjective adverse event reports were identified in 7 of the observational studies. IMPLICATIONS: Discontinuation rates of biosimilar mAbs may increase due to subjective effects after switching from an originator mAb. These findings highlight the need for further patient education and well-designed, observational switching studies as well as the collection and analysis of identifiable pharmacovigilance and postmarketing data of biologics, including biosimilars. The collection of real-world results is particularly pertinent for mAbs other than CT-P13, for which there is currently a lack of observational switching data.

An easy-to-use baseline scoring system to predict response to peginterferon alfa-2a in patients with chronic hepatitis B in resource-limited settings.

BACKGROUND: Approximately one-third of patients have durable responses after finite (48-week) treatment with peginterferon alfa-2a. The ability to identify patients likely to respond would be particularly useful in resource-limited settings. METHODS: Data from 1,363 peginterferon alfa-2a recipients (955 hepatitis B 'e' antigen [HBeAg]-positive and 408 -negative) in six studies were analysed. Baseline scoring systems were developed using generalized additive models and multiple logistic regression analysis to predict virological response (VR; HBV DNA <2,000 IU/ml), alone or combined with alanine aminotransferase (ALT) normalization (CR) at 24 weeks post-treatment. RESULTS: Based on the final models, points were assigned for age ≥45 (0) or <45 years (1); male (0) or female (1); hepatitis B surface antigen (HBsAg) >25,000 (0), >7,500-≤25,000 (1), >1,250-≤7,500 (2) or ≤1,250 IU/ml (4); HBV DNA >5 (0) or ≤5 log10 IU/ml (2) and ALT ratio >1-7 (0) or either ≤1 or >7 (1). Higher total scores (range 0-9) indicate higher likelihood of response. VR and CR rates were 28.5% (388/1,363) and 24.4% (332/1,363), respectively, and increased with increasing score: score 0-1 (n=257), VR 14.8%, CR 12.8%; score 2-3 (n=711), VR 23.1%, CR 20.1%; score ≥4 (n=395), VR 47.1%, CR 39.5%. CONCLUSIONS: An easy-to-use baseline scoring system for use in settings where HBeAg status and HBV genotypes are unavailable would allow clinicians to identify patients with a low or high chance of achieving a durable post-treatment response to peginterferon alfa-2a. The tool can be used to inform treatment decisions in resource-limited settings.

Monoclonal Antibody Biosimilars in Oncology: Critical Appraisal of Available Data on Switching.

PURPOSE: With the introduction of biosimilars of anticancer monoclonal antibodies (mAbs) in oncology, physicians are potentially confronted with the question whether it is clinically adequate to switch patients who are clinically stable on treatment with the reference product to a newly available biosimilar (or vice versa/from 1 biosimilar to another). For a proper impact assessment of switching, robust, product-specific, and clinically relevant evidence should be required, ideally including data from appropriately designed switching studies. In this article, we assess the current body of switching data available for approved or proposed biosimilars of anticancer mAbs. METHODS: PubMed was systematically searched and ClinicalTrials.gov and abstract databases of selected congresses were hand-searched to identify all switching studies including biosimilars of anticancer mAbs. FINDINGS: We identified 8 switching studies with biosimilars of rituximab (CT-P10, GP2013, PF-05280586, and BCD-020) and trastuzumab (ABP 980). Two were performed in oncology indications and the other 6 in rheumatoid arthritis (RA). Key elements of a well-designed switching study, such as randomization and blinding, were contained in several of the studies, but significant limitations were also present. The most frequent limitations were low statistical power because of small patient numbers, lack of an appropriate control arm, short follow-up, chosen outcome measures, and (for studies performed in RA) the concern whether switching data can be extrapolated to oncology indications. Accordingly, the data from these studies need to be interpreted with caution. Of note, all identified studies included a single switch only, whereas multiple switches may occur in the real-world setting. The scientific need to evaluate the impact of repeated switching has been recognized by the US Food and Drug Administration, who incorporated such a requirement in its draft guidance on interchangeability. IMPLICATIONS: From the scarce data available, the consequences of switching between reference product mAbs and their biosimilar(s) in the oncology setting are as yet unknown. Additional clinical evidence from well-designed switching studies is needed to guide switching decisions.

A genotype-specific baseline score predicts post-treatment response to peginterferon alfa-2a in hepatitis B e antigen-negative chronic hepatitis B.

BACKGROUND: Peginterferon alfa-2a induces durable responses in some hepatitis B e antigen-negative patients, but robust pretreatment predictors are not available to identify likely responders. In this study we aimed to develop genotype-specific baseline scoring systems to predict response. METHODS: Data from 323 hepatitis B e antigen-negative peginterferon alfa-2a recipients from three studies were analyzed. Scoring systems were developed using generalized additive models and multiple logistic regression analysis. Response was defined as hepatitis B virus DNA <2000 IU/mL alone (virological response) or in combination with alanine aminotransferase normalization (combined response) 48 weeks post-treatment. RESULTS: Points were assigned to genotype B/C patients for: age, alanine aminotransferase ratio, genotype B or C, and hepatitis B surface antigen level; and to genotype D patients for age, hepatitis B surface antigen level and hepatitis B virus DNA level. Higher total scores (range 0-5 for B/C; 0-3 for D) indicated a higher likelihood of response. Among genotype B/C patients with scores of 0-1, 2 and ≥3, respectively, virological response rates were 16.7%, 25.8% and 70.2%, and combined response rates were 12.5%, 21.0% and 57.4%. Among genotype D patients with scores of 0-1, 2 and 3, respectively, virological response rates were 10.1%, 28.0% and 50.0%, and combined response rates were 7.8%, 28.0% and 33.3%. CONCLUSION: Genotype-specific baseline scoring systems can identify hepatitis B e antigen-negative patients with low or high likelihood of achieving sustained responses to peginterferon alfa-2a.

Efficacy and safety profile of boceprevir- or telaprevir-based triple therapy or dual peginterferon alfa-2a or alfa-2b plus ribavirin therapy in chronic hepatitis C: the real-world PegBase observational study.

BACKGROUND: The aim of the study was to determine the efficacy and safety of triple therapy with a first-generation protease inhibitor (PI; boceprevir, telaprevir) plus peginterferon alfa-2a or -2b plus ribavirin, and dual therapy (peginterferon alfa-2a or -2b plus ribavirin) in patients with chronic hepatitis C (CHC) in routine clinical practice. METHODS: PegBase was an international, prospective, observational study in which 4441 patients with CHC were enrolled in 27 countries. This analysis focuses on results in 4100 treatment-naïve and previously treated patients treated with PI-based triple therapy or dual therapy, according to the discretion of the investigator and local standards of practice. The primary efficacy outcome was sustained virological response after 12-week follow up (SVR12). RESULTS: SVR12 rates in treatment-naïve genotype (G) 1 patients were 56.6% and 62.9% for recipients of boceprevir plus peginterferon alfa-2a/ribavirin and boceprevir plus peginterferon alfa-2b/ribavirin, respectively, and 65.3% and 58.6% for recipients of telaprevir plus peginterferon alfa-2a/ribavirin and telaprevir plus peginterferon alfa-2b/ribavirin, respectively. In previously treated patients assigned to these four regimens, SVR12 rates were 43.6%, 48.3%, 60.3% and 56.1%, respectively. Among treatment-naïve patients assigned to peginterferon alfa-2a/ribavirin and peginterferon alfa-2b/ribavirin, respectively, SVR12 rates were 49.2% and 41.9% in G1 patients, 75.7% and 83.3% in G2 patients, 65.9% and 65.9% in G3 patients, and 49.7%, and 51.1% in G4 patients. The safety and tolerability of dual and triple therapy were consistent with previous reports. CONCLUSION: The efficacy and safety of first-generation PI-based triple-therapy and dual-therapy regimens in this real-world cohort were broadly comparable to those of previous studies.

A Predictive Model for Selecting Patients with HCV Genotype 3 Chronic Infection with a High Probability of Sustained Virological Response to Peginterferon Alfa-2a/Ribavirin.

BACKGROUND: Access to direct-acting antiviral agents (DAAs) is restricted in some settings; thus, the European Association for the Study of the Liver recommends dual peginterferon/ribavirin (PegIFN/RBV) therapy wherever DAAs are unavailable. HCV genotype (GT) 3 infection is now the most difficult genotype to eradicate and PegIFN/RBV remains an effective option. The goal of this study was to devise a simple predictive score to identify GT3 patients with a high probability of achieving a sustained virologic response (SVR) with PegIFN alfa-2a/RBV therapy. METHODS: Relationships between baseline characteristics and SVR were explored by multiple logistic regression models and used to develop a simple scoring system to predict SVR using data from 1239 treatment-naive GT3 patients who received PegIFN alfa-2a/RBV for 24 weeks in two large observational cohort studies. RESULTS: The score was validated using a database of 473 patients. Scores were assigned for six factors as follows: age (years) (≤40: 2 points; >40 but ≤55: 1); bodyweight (kg) (<70: 2; ≥70 but <90: 1); no cirrhosis/transition to cirrhosis (2); ALT ≤2.5 x ULN (1); platelets (109/L) (>200: 2; ≥100 but <200: 1); HCV RNA (<400,000 IU/mL: 1). The points are summed to arrive at a score ranging from 0‒10 where higher scores indicate higher chances of SVR; 141, 123, 203, 249, 232, and 218 patients had total scores of 0‒4, 5, 6, 7, 8, and 9-10, respectively, among whom SVR rates were 45%, 62%, 72%, 76%, 84%, and 89%. Among 622 patients who had scores of 6‒10 and HCV RNA <50 IU/mL by treatment week 4 the SVR rate was 86% (532/622). CONCLUSIONS: A simple baseline scoring system involving age, bodyweight, cirrhosis status, ALT level, platelet count and HCV RNA level can be used to identify treatment-naive Caucasian patients with HCV GT3 infection with a high probability of SVR with PegIFN alfa-2a/RBV therapy.

Simple Predictive Model for Identifying Patients with Chronic Hepatitis C and Hepatitis C Virus Genotype 4 Infection with a High Probability of Sustained Virologic Response with Peginterferon Alfa-2a/Ribavirin: Pooled Analysis of Data from Two Large, International Cohort Studies.

INTRODUCTION: Wherever access to direct-acting antiviral agents is restricted, dual peginterferon/ribavirin (PegIFN/RBV) therapy remains an option for treatment of hepatitis C virus (HCV) genotype 4 (GT4) infection, which predominates in the Middle East and Sub-Saharan Africa. Our goal was to develop a baseline scoring system to identify GT4-infected patients with a low or high probability of achieving a sustained virologic response (SVR) with PegIFN alfa-2a/RBV using data from two large cohort studies. METHODS: Associations between baseline characteristics and SVR were explored by generalized additive models and multiple logistic regression analysis to develop a predictive model, which was then checked by bootstrapping. The score comprised four factors with points assigned thus: age ≤40, 3 points; >40 but ≤55, 2 points; alanine aminotransferase ≤1 or >3× the upper limit of normal, 1 point; no cirrhosis, 1 point; HCV RNA <50,000 IU/mL, 2 points; 50,000 to <400,000 IU/mL, 1 point. The values for a given patient are summed to produce a score from 0 to 7 where higher scores indicate higher chances of SVR. RESULTS: Among the 459 patients, 28 (6%), 50 (11%), 92 (20%), 121 (26%), 103 (22%), and 65 (14%) patients had scores of 0-1, 2, 3, 4, 5, and 6-7, respectively, with respective SVR rates of 11%, 28%, 50%, 57%, 63%, and 83%. Relapse rates decreased with increasing prediction score (80%, 39%, 15%, 19%, 5%, and 7%, respectively). SVR rates were consistently higher in Caucasian than Black patients and in patients with a rapid virologic response HCV RNA <50 IU/mL at week 4); however, the trend toward higher SVR rates with increasing score remained apparent in each subgroup. CONCLUSION: In conclusion, a simple scoring system can be used to identify GT4-infected patients with a high probability of achieving an SVR with PegIFN alfa-2a/RBV. FUNDING: F. Hoffmann-La Roche Ltd.

Boceprevir Plus Peginterferon Alfa-2a/Ribavirin in Treatment-Naïve Hepatitis C Virus Genotype 1 Patients: International Phase IIIb/IV TriCo Trial.

INTRODUCTION: Boceprevir was not previously studied with peginterferon alfa-2a/ribavirin in phase III trials in treatment-naïve chronic hepatitis C patients. The international phase IIIb/IV TriCo study was, therefore, designed to evaluate boceprevir in combination with peginterferon alfa-2a/ribavirin in treatment-naïve genotype 1 patients. METHODS: A total of 165 treatment-naïve genotype 1 patients were assigned to boceprevir plus peginterferon alfa-2a/ribavirin therapy according to the label. All patients received a 4-week lead-in with peginterferon alfa-2a/ribavirin, after which boceprevir (2400 mg/day) was introduced. The total duration of treatment ranged from 28 to 48 weeks depending on the virological response at Weeks 4, 8, and 24, and on fibrosis status. The primary efficacy outcome was sustained virological response (SVR) [undetectable hepatitis C virus (HCV) ribonucleic acid (RNA) 12 weeks after actual end of treatment, SVR12]. RESULTS: The overall SVR12 rate was 81% (133/165, 95% confidence interval 74-86%). After 8 weeks of treatment, 61% of patients had undetectable HCV RNA, and 78 patients (47%) had an early response (undetectable HCV RNA at Weeks 8 and 24) and were eligible to stop all therapy at Week 28. Among early responders the SVR12 rate was 95% (74/78), and among patients with cirrhosis assigned to 48 weeks' treatment, the SVR12 rate was 67% (14/21). The overall relapse rate was 7% (10/143), and was 4% (3/77) among early responders. The most common adverse events were anemia (41%), neutropenia (32%), and dysgeusia (31%). CONCLUSION: High SVR12 rates can be achieved with boceprevir plus peginterferon alfa-2a/ribavirin in treatment-naïve HCV genotype 1 patients, including patients with well-compensated cirrhosis. Treatment is well tolerated when label restrictions are taken into account. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT01591460. FUNDING: F. Hoffmann-La Roche Ltd.

Impact of Safety-Related Dose Reductions or Discontinuations on Sustained Virologic Response in HCV-Infected Patients: Results from the GUARD-C Cohort.

BACKGROUND: Despite the introduction of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, peginterferon alfa/ribavirin remains relevant in many resource-constrained settings. The non-randomized GUARD-C cohort investigated baseline predictors of safety-related dose reductions or discontinuations (sr-RD) and their impact on sustained virologic response (SVR) in patients receiving peginterferon alfa/ribavirin in routine practice. METHODS: A total of 3181 HCV-mono-infected treatment-naive patients were assigned to 24 or 48 weeks of peginterferon alfa/ribavirin by their physician. Patients were categorized by time-to-first sr-RD (Week 4/12). Detailed analyses of the impact of sr-RD on SVR24 (HCV RNA <50 IU/mL) were conducted in 951 Caucasian, noncirrhotic genotype (G)1 patients assigned to peginterferon alfa-2a/ribavirin for 48 weeks. The probability of SVR24 was identified by a baseline scoring system (range: 0-9 points) on which scores of 5 to 9 and <5 represent high and low probability of SVR24, respectively. RESULTS: SVR24 rates were 46.1% (754/1634), 77.1% (279/362), 68.0% (514/756), and 51.3% (203/396), respectively, in G1, 2, 3, and 4 patients. Overall, 16.9% and 21.8% patients experienced ≥1 sr-RD for peginterferon alfa and ribavirin, respectively. Among Caucasian noncirrhotic G1 patients: female sex, lower body mass index, pre-existing cardiovascular/pulmonary disease, and low hematological indices were prognostic factors of sr-RD; SVR24 was lower in patients with ≥1 vs. no sr-RD by Week 4 (37.9% vs. 54.4%; P = 0.0046) and Week 12 (41.7% vs. 55.3%; P = 0.0016); sr-RD by Week 4/12 significantly reduced SVR24 in patients with scores <5 but not ≥5. CONCLUSIONS: In conclusion, sr-RD to peginterferon alfa-2a/ribavirin significantly impacts on SVR24 rates in treatment-naive G1 noncirrhotic Caucasian patients. Baseline characteristics can help select patients with a high probability of SVR24 and a low probability of sr-RD with peginterferon alfa-2a/ribavirin.

IL28B genotype is associated with cirrhosis or transition to cirrhosis in treatment-naive patients with chronic HCV genotype 1 infection: the international observational Gen-C study.

BACKGROUND AND PURPOSE: Contradictory data exist on the association between host interleukin-28B (IL28B) rs12979860 genotype and liver fibrosis in patients with chronic hepatitis C (CHC). This large, international, observational study (NCT01675427/MV25600) investigated relationships between IL28B rs12979860 genotype and liver fibrosis stage in CHC patients. METHODS: A total of 3003 adult, treatment-naive CHC patients were enrolled into the study. Patients made one study visit to provide a blood sample for genotyping; other data were obtained from medical records. RESULTS: 2916 patients comprised the analysis population; the majority were enrolled in Europe (n = 2119), were Caucasian (n = 2582) and had hepatitis C virus (HCV) genotype (G)1 infection (n = 1702) (G2 = 323, G3 = 574, G4 = 260). Distribution of IL28B genotypes varied according to region of enrolment, patient ethnicity and HCV genotype. A significant association was observed between increasing number of IL28B T alleles and the prevalence of cirrhosis/transition to cirrhosis (based on biopsy or non-invasive assessments) in G1-infected patients (CC = 22.2% [111/499], CT = 27.5% [255/928], TT = 32.3% [87/269]; p = 0.0018). The association was significant in the large subgroup of European Caucasian G1 patients (n = 1245) but not in the smaller Asian (n = 25), Latin American (n = 137) or Middle Eastern (n = 289) G1 subgroups. IL28B genotype was not associated with liver fibrosis stage in patients with HCV G2, G3 or G4 infection. CONCLUSION: This large, international study found that IL28B rs12979860 genotype is significantly associated with liver fibrosis stage in CHC patients with HCV G1 infection. This association was evident in European Caucasians but not in G1-infected patients from Asia, Latin America or the Middle East.

Assessing the relative effectiveness and tolerability of treatments in small cell lung cancer: a network meta-analysis.

BACKGROUND: The combination of Cisplatin plus Etoposide (EP) is currently the standard treatment for small cell lung cancer (SCLC). However, a large number of alternative treatments (monotherapies and combinations) have been studied in randomized controlled trials (RCTs) to identify more effective treatments. Aim of the present study was to assess the relative effectiveness and tolerability of these treatments. METHODS: PubMed, EMBASE and Cochrane Central Register of Controlled Trials were systematically searched to identify all RCTs that compared treatments for SCLC. Then, effectiveness of the treatments relative to the combination of Cisplatin plus Etoposide, reference treatment) was estimated by performing a network of treatments analysis. The analysis evaluated two efficacy outcomes (complete response - CR and objective response rate - ORR) and two tolerability outcomes (neutropenia and febrile neutropenia). All RCTs that provided data for calculating the odds ratios (OR) for the selected outcomes were considered. The network analysis involved direct and indirect analyses. RESULTS: We identified 71 articles eligible for inclusion, involving 91 different treatments. In total, 16,026 patients were included in the analysis. In the direct analysis the combination of Cisplatin plus Cyclophosphamide plus Etoposide plus Epirubicin showed better response than EP for the ORR outcome, but with worse tolerability (presence of neutropenia). The indirect analysis revealed that the combination of Cisplatin plus Doxorubicin plus Etoposide (plus Vincrisitine) showed better response that EP for the ORR outcome. CONCLUSIONS: No therapy shows better response for the two efficacy outcomes (CR and ORR); though, Cisplatin plus Doxorubicin plus Etoposide plus Vincrisitine might be a promising therapy for SCLC. The results should be interpreted with caution because the network was dominated by indirect comparisons. Large scale head-to-head RCTs are needed to confirm the present findings.

Variants of the MTHFR gene and susceptibility to acute lymphoblastic leukemia in children: a synthesis of genetic association studies.

BACKGROUND: Acute lymphoblastic leukemia (ALL) is a complex disease with genetic background. The genetic association studies (GAS) that investigated the association between ALL and the MTHFR C677T and A1298C gene variants have produced contradictory or inconclusive results. MATERIALS AND METHODS: In order to decrease the uncertainty of estimated genetic risk effects, a meticulous meta-analysis of published GAS related the variants in the MTFHR gene with susceptibility to ALL was conducted. The risk effects were estimated based on the odds ratio (OR) of the allele contrast and the generalized odds ratio (OR(G)). Cumulative and recursive cumulative meta-analyses were also performed. RESULTS: The analysis showed marginal significant association for the C677T variant, overall [OR=0.91 (0.82-1.00) and OR(G)=0.89 (0.79-1.01)], and in Whites [OR=0.88 (0.77-0.99) and OR(G)=0.85 (0.73-0.99)]. The A1298C variant produced non-significant results. For both variants, the cumulative meta-analysis did not show a trend of association as evidence accumulates and the recursive cumulative meta-analysis indicated lack of sufficient evidence for denying or claiming an association. CONCLUSION: The current evidence is not sufficient to draw definite conclusions regarding the association of MTHFR variants and development of ALL.

Evidence of association between methylenetetrahydrofolate reductase gene and susceptibility to breast cancer: a candidate-gene association study in a South-eastern European population.

The methylenetetrahydrofolate reductase (MTHFR) gene has been proposed as a candidate gene for breast cancer (BC). However, the specific role of MTHFR polymorphisms and haplotypes has not been fully clarified and replicated. We examined the association of two common MTHFR polymorphisms (C677T and A1298C) and their haplotypes in a candidate-gene association study, involving 300 female patients with BC and 283 healthy women. The single locus analysis for the two polymorphisms revealed an association only for the C677T polymorphism [odds ratio (95% confidence interval), OR=2.05 (1.21-3.48)], but adjustment for age diminished this association [OR=1.76 (0.92-3.42)]. The menopausal status showed no significant effect in the association between the MTHFR polymorphisms and BC. The analysis of haplotypes showed an association for the C677-A1298 haplotypes (p=0.04). The available evidence from our study may support a contributory role of MTHFR polymorphisms in BC development. Future larger studies may help in elucidating the genetics of BC further.