Non-Hodgkin's Lymphomas of Waldeyer's Ring

From 1970 to 1980, 171 consecutive cases with non-Hodgkin's lymphomas (NHL) of Waldeyer's ring were admitted to this Institute. The cases were reviewed to evaluate whether involvement of Waldeyer's ring might represent a distinct clinicopathologic entity. Adequate pathologic staging was performed in 86% of cases. All slides were reviewed, and the histologic diagnosis given according to the Rappaport classification, the Kiel classification, and the recent Working Formulation of NHL for Clinical Usage. Waldeyer's ring alone was involved in 12.3% of the cases at presentation; regional nodes were positive in one-third (35.7%), and distant involvement was detected in half of the patients (52%). The tonsils represented the most frequent site of involvement by NHL within Waldeyer's ring. Treatments employed were heterogeneous, but most of the patients with stage I-II received radiotherapy alone. The present series shows that the association of involvement of Waldeyer's ring and the stomach by NHL occurs in less than 10% of the cases. Treatment results and patterns of recurrence fail to differentiate NHL involving Waldeyer's ring from those of other sites. Prognosis remains related to the classical variables and is independent of the site of onset.

Blood Concentrations of Tumor Necrosis Factor-Alpha in Malignant Lymphomas and Their Decrease as a Predictor of Disease Control in Response to Low-Dose Subcutaneous Immunotherapy with Interleukin-2

Tumor necrosis factor-alpha (TNF-α), a cytokine provided by both immunomodulating and inflammatory activities, has been described to be abnormally increased in the blood of patients affected by malignant lymphomas, particularly NHL. However, the biological and clinical significance of TNF-α secretion in malignant lymphomas is still controversial. The present study was carried out to further define TNF-α secretion in untreated malignant lymphomas and during low-dose IL-2 immunotherapy. The study included 80 malignant lymphoma patients, 54 of whom were affected by HD and the other 26 by NHL. The mean TNF-α serum concentrations observed in untreated lymphoma patients were significantly higher than those seen in the healthy controls, without significant differences between HD and NHL. Moreover, both HD and NHL lymphoma patients at clinical stage III-IV showed significantly higher mean TNF-α levels than those at clinical stage I-II. Finally, patients with systemic symptoms had higher mean TNF-α concentrations than those without any systemic symptoms, even though statistical significance was observed only for NHL patients. In a second study we have evaluated changes in TNF-α levels in seven evaluable lymphoma patients (NHL: 6; HD: 1) - who did not respond to conventional therapies - during subcutaneous low-dose IL-2 (3 MIU/day 6 days/week for 4 weeks). Long-term stable disease was achieved in four patients with NHL, whereas the other three progressed. In patients with stable disease the mean TNF-α concentrations significantly decreased during treatment, whereas they increased in progressing patients. This study, by showing an abnormally enhanced TNF-α secretion in both NHL and HD patients with advanced disease and systemic symptoms and a decrease in its levels in patients who achieved disease control on IL-2 immunotherapy, appears to confirm the unfavorable prognostic significance of enhanced TNF-α levels in malignant lymphomas.

Early Chemotherapy Intensification With Escalated BEACOPP in Patients With Advanced-Stage Hodgkin Lymphoma With a Positive Interim Positron Emission Tomography/Computed Tomography Scan After Two ABVD Cycles: Long-Term Results of the GITIL/FIL HD 0607 Trial

Purpose

To investigate the progression-free survival (PFS) of patients with advanced Hodgkin lymphoma (HL) after a risk-adapted treatment strategy that was based on a positive positron emission tomography scan performed after two doxorubicin, vinblastine, vincristine, and dacarbazine (ABVD) cycles (PET2).

Patients and Methods

Patients with advanced-stage (IIB to IVB) HL were consecutively enrolled. After two ABVD cycles, PET2 was performed and centrally reviewed according to the Deauville five-point scale. Patients with a positive PET2 were randomly assigned to four cycles of escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP) followed by four cycles of standard BEACOPP with or without rituximab. Patients with a negative PET2 continued ABVD, and those with a large nodal mass at diagnosis (≥ 5 cm) in complete remission with a negative PET at the end of chemotherapy were randomly assigned to radiotherapy or no further treatment. The primary end point was 3-year PFS.

Results

Of 782 enrolled patients, 150 (19%) had a positive and 630 (81%) a negative PET2. The 3-year PFS of all patients was 82%. The 3-year PFS of those with a positive and negative PET2 was 60% and 87%, respectively ( P < .001). The 3-year PFS of patients with a positive PET2 assigned to BEACOPP with or without rituximab was 63% versus 57% ( P = .53). In 296 patients with both interim and post-ABVD–negative PET who had a large nodal mass at diagnosis, radiotherapy was randomly added after chemotherapy without a significant PFS improvement (97% v 93%, respectively; P = .29). The 3-year overall survival of all 782 patients was 97% (99% and 89% for PET2 negative and positive, respectively).

Conclusion

The PET-driven switch from ABVD to escalated BEACOPP is feasible and effective in high-risk patients with advanced-stage HL.

Serum Cytokine in Response to Chemo-Radiotherapy for Hodgkin's Disease

Aims and Background

Mediastinal radiotherapy and multiple-drug chemotherapy, including bleomycin employed in the treatment of Hodgkin's disease, can produce lung toxicity leading to fibrosis. There is increasing evidence of the involvement in the fibrosing process of different cytokines and growth factors such as TNF-alfa, IL-1 beta, TGF-beta and PDGF.

Material and Methods

In a pilot study, we evaluated lung function in 20 patients suffering from Hodgkin's disease, mainly in stage II A, submitted to multiple-drug chemotherapy including bleomycin (ABVD) and mediastinal radiotherapy and correlated its modifications with serum concentration of the cytokines determined by immunoenzymatic assay. Spirometry and transfer lung function for carbon monoxide (DLCO) were performed before, at the end of chemotherapy, at the end of radiotherapy and after a follow-up of 6 and 12 months.

Results

DLCO decreased at the end of the combined treatment and then remained constantly decreased. TNF-alfa, TGF-beta and PDGF-alfa concentrations did not change, whereas IL-1 beta significantly increased after the completion of the combined treatment and after a follow-up of 6–months and then declined to normal values after 12 months. The serum concentration of the cytokine was significantly higher in patients who had a DLCO <75% of predicted after 1 year than in patients with a DLCO >75%.

Conclusions

The results indicate a potential role of IL-1 beta in the pathogenesis of chemoradiotherapy-induced lung toxicity, which needs to be confirmed in a larger patient population.

Lessons from the Meningitis Vaccine Project

From 2001 to 2017 the Meningitis Vaccine Project (MVP), a Gates Foundation funded partnership between PATH and the World Health Organization (WHO), successfully developed, tested, licensed, and introduced an affordable new Group A meningococcal conjugate vaccine, MenAfriVac, in sub-Saharan Africa. The vaccine was well received, and from 2010 to 2016, over 260 million Africans have received a dose of the vaccine in campaigns largely directed at 1–29-year olds. The public health impact has been dramatic with the elimination of Group A meningococcal infections wherever the vaccine has been used at public health scale. Over its 16-year life span, MVP faced many challenges, and lessons were learned that may be of interest to other groups seeking to develop vaccine products for resource-poor countries. We have chosen to highlight six elements that were keys to the success of the project: (a) country and African regional engagement during all phases of the project; (b) the evolution of the WHO/PATH partnership; (c) funding the introduction of MenAfriVac in meningitis belt countries; (d) regulatory challenges; (e) clinical trials in Africa and India; and (f ) the realities of vaccine development partnerships.

A genetically inactivated two-component acellular pertussis vaccine, alone or combined with tetanus and reduced-dose diphtheria vaccines, in adolescents: a phase 2/3, randomised controlled non-inferiority trial

BACKGROUND

Increasing evidence shows that protection induced by acellular pertussis vaccines is short-lived, requiring repeated booster vaccination to control pertussis disease. We aimed to assess the safety and immunogenicity of a recombinant acellular pertussis vaccine containing genetically inactivated pertussis toxin and filamentous haemagglutinin, as either a monovalent vaccine (aP_[PTgen/FHA]) or in combination with tetanus and reduced-dose diphtheria vaccines (TdaP_[PTgen/FHA]), versus a licensed tetanus and reduced-dose diphtheria and acellular pertussis combination vaccine (Tdap).

METHODS

We did this phase 2/3, randomised controlled non-inferiority trial at two sites in Bangkok, Thailand. Healthy adolescents (aged 12-17 years) were randomly assigned (1:1:1), via a computer-generated randomisation list with block sizes of three, to receive one dose (0·5 mL) of aP_(PTgen/FHA), TdaP_(PTgen/FHA), or Tdap (comparator). Clinical research staff responsible for participant randomisation, vaccine preparation and administration, and accountability were aware of group allocation. However, allocation was concealed from all other site study staff, data management personnel, statisticians, laboratory staff, and study participants. The primary outcome was non-inferior immunogenicity of TdaP_(PTgen/FHA) to Tdap based on seroconversion rates (a four-fold increase or more) for pertussis toxin and filamentous haemagglutinin IgG antibodies 28 days after vaccination, with a predefined 10% margin of equivalence. We did analysis by per protocol. This study is registered with the Thai Clinical Trial Registry, number TCTR20150703002.

FINDINGS

Between July 6 and Aug 20, 2015, we allocated 450 participants to receive one dose of TdaP_(PTgen/FHA) (n=150), aP_(PTgen/FHA) (n=150), or comparator Tdap (n=150). 28 days after vaccination, seroconversion rates for anti-pertussis toxin IgG were 96·6% (95% CI 93·8-99·5; n=144) in the TdaP_(PTgen/FHA) group and 55·0% (47·1-63·0; n=82) in the comparator Tdap group (difference 41·6%, 95% CI 33·1-50·1; p<0·0001). Seroconversion rates for anti-filamentous haemagglutinin were 82·6% (95% CI 76·5-88·6; n=123) in the TdaP_(PTgen/FHA) group and 54·4% (46·4-62·4; n=81) in the comparator group (difference 28·2%, 95% CI 18·1-38·2 p<0·0001). 28 days after vaccination, seroconversion rates in the aP_(PTgen/FHA) group were 96·0% (95% CI 92·8-99·1; n=142) for anti-pertussis toxin IgG and 93·2% (89·2-97·3; n=138) for anti-filamentous haemagglutinin IgG. These findings support the non-inferior immunogenicity of TdaP_(PTgen/FHA) over comparator Tdap. Reactogenicity and incidence of adverse events were similar between groups.

INTERPRETATION

The new TdaP_(PTgen/FHA) vaccine is safe and induces higher pertussis responses 28 days after vaccination than does the available licensed Tdap booster vaccine. Results of our trial led to the licensure of new acellular pertussis vaccines containing genetically inactivated pertussis toxin in Thailand. The availability of recombinant monovalent pertussis vaccines that induce high antibody responses provides the medical community and consumers with the opportunity to vaccinate against pertussis when immunisation against diphtheria and tetanus is not required or not desired. Studies are underway to pave the way for licensure studies of this acellular pertussis vaccine in other countries.

FUNDING

BioNet-Asia.

Early reduction of serum TARC levels may predict for success of ABVD as frontline treatment in patients with Hodgkin Lymphoma

BACKGROUND

Many efforts have been made to predict prognosis of newly diagnosed Hodgkin Lymphoma (HL) patients. Objective of this study was to investigate the association between early reduction of Thymus and Activation-Regulated Chemokine after the first ABVD cycle (TARC-1) and prognosis of HL patients.

METHODS

Serum samples of 116 HL patients were collected at baseline, after every ABVD cycle and during follow-up. The 99th centile of TARC distribution in a group of 156 independent healthy subjects (800pg/ml) was considered as cut-off for discriminating between abnormal and normal TARC values.

FINDINGS

101 patients out of 116 had baseline TARC above 800pg/ml (median value 27515pg/ml (IQR, 11001-68139)) and were the object of this analysis. TARC-1 significantly decreased to a median value of 556pg/ml (IQR, 378-977pg/ml). TARC-1 values below 800pg/ml were associated with success of therapy (p=0.0003) and PET-2 negativity (p=0.001). TARC-1≤800pg/ml identified a population with a significantly higher 5-years PFS in the whole cohort (90.1% vs 55.6%; p<0.0001) and in both subgroups of advanced (p=0.003) and early stage patients (p=0.021). At multivariable analysis, TARC-1 was significant independent predictor of PFS (p=0.0035).

INTERPRETATION

Early reduction of TARC serum levels can predict success of treatment, being associated with achievement of interim PET-2 negative and favorable long-term outcome in HL patients receiving ABVD as front-line therapy.

Secondary malignant neoplasms, progression-free survival and overall survival in patients treated for Hodgkin lymphoma: a systematic review and meta-analysis of randomized clinical trials

Treatment intensification to maximize disease control and reduced intensity approaches to minimize the risk of late sequelae have been evaluated in newly diagnosed Hodgkin lymphoma. The influence of these interventions on the risk of secondary malignant neoplasms, progression-free survival and overall survival is reported in the meta-analysis herein, based on individual patient data from 9498 patients treated within 16 randomized controlled trials for newly diagnosed Hodgkin lymphoma between 1984 and 2007. Secondary malignant neoplasms were meta-analyzed using Peto’s method as time-to-event outcomes. For progression-free and overall survival, hazard ratios derived from each trial using Cox regression were combined by inverse-variance weighting. Five study questions (combined-modality treatment vs. chemotherapy alone; more extended vs. involved-field radiotherapy; radiation at higher doses vs. radiation at 20 Gy; more vs. fewer cycles of the same chemotherapy protocol; standard-dose chemotherapy vs. intensified chemotherapy) were investigated. After a median follow-up of 7.4 years, dose-intensified chemotherapy resulted in better progression-free survival rates (P=0.007) as compared with standard-dose chemotherapy, but was associated with an increased risk of therapy-related acute myeloid leukemia/myelodysplastic syndromes (P=0.0028). No progression-free or overall survival differences were observed between combined-modality treatment and chemotherapy alone, but more secondary malignant neoplasms were seen after combined-modality treatment (P=0.010). For the remaining three study questions, outcomes and secondary malignancy rates did not differ significantly between treatment strategies. The results of this meta-analysis help to weigh up efficacy and secondary malignancy risk for the choice of first-line treatment for Hodgkin lymphoma patients. However, final conclusions regarding secondary solid tumors require longer follow-up.

Prognostic Value of Bone Marrow Tracer Uptake Pattern in Baseline PET Scans in Hodgkin Lymphoma: Results from an International Collaborative Study

PET/CT-ascertained bone marrow involvement (BMI) constitutes the single most important reason for upstaging by PET/CT in Hodgkin lymphoma (HL). However, BMI assessment in PET/CT can be challenging. This study analyzed the clinicopathologic correlations and prognostic meaning of different patterns of bone marrow (BM) ¹⁸F-FDG uptake in HL. Methods: One hundred eighty newly diagnosed early unfavorable and advanced-stage HL patients, all scanned at baseline and after 2 adriamycin-bleomycin-vinblastine-dacarbazine (ABVD) courses with ¹⁸F-FDG PET, enrolled in 2 international studies aimed at assessing the role of interim PET scanning in HL, were retrospectively included. Patients were treated with ABVD × 4-6 cycles and involved-field radiation when needed, and no treatment adaptation on interim PET scanning was allowed. Two masked reviewers independently reported the scans. Results: Thirty-eight patients (21.1%) had focal lesions (fPET⁺), 10 of them with a single (unifocal) and 28 with multiple (multifocal) BM lesions. Fifty-three patients (29.4%) had pure strong (>liver) diffuse uptake (dPET⁺) and 89 (48.4%) showed no or faint (≤liver) BM uptake (nPET⁺). BM biopsy was positive in 6 of 38 patients (15.7%) for fPET⁺, in 1 of 53 (1.9%) for dPET⁺, and in 5 of 89 (5.6%) for nPET⁺ dPET⁺ was correlated with younger age, higher frequency of bulky disease, lower hemoglobin levels, higher leukocyte counts, and similar diffuse uptake in the spleen. Patients with pure dPET⁺ had a 3-y progression-free survival identical to patients without any ¹⁸F-FDG uptake (82.9% and 82.2%, respectively, P = 0.918). However, patients with fPET+ (either unifocal or multifocal) had a 3-y progression-free survival significantly inferior to patients with dPET+ and nPET+ (66.7% and 82.5%, respectively, P = 0.03). The κ values for interobserver agreement were 0.84 for focal uptake and 0.78 for diffuse uptake. Conclusion: We confirmed that ¹⁸F-FDG PET scanning is a reliable tool for BMI assessment in HL, and BM biopsy is no longer needed for routine staging. Moreover, the interobserver agreement for BMI in this study proved excellent and only focal ¹⁸F-FDG BM uptake should be considered as a harbinger of HL.

Safety and immunogenicity of a combined Tetanus, Diphtheria, recombinant acellular Pertussis vaccine (TdaP) in healthy Thai adults

Background: An acellular Pertussis (aP) vaccine containing recombinant genetically detoxified Pertussis Toxin (PTgen), Filamentous Hemagglutinin (FHA) and Pertactin (PRN) has been developed by BioNet-Asia (BioNet). We present here the results of the first clinical study of this recombinant aP vaccine formulated alone or in combination with tetanus and diphtheria toxoids (TdaP). Methods: A phase I/II, observer-blind, randomized controlled trial was conducted at Mahidol University in Bangkok, Thailand in healthy adult volunteers aged 18–35 y. The eligible volunteers were randomized to receive one dose of either BioNet's aP or Tetanus toxoid-reduced Diphtheria toxoid-acellular Pertussis (TdaP) vaccine, or the Tdap Adacel® vaccine in a 1:1:1 ratio. Safety follow-up was performed for one month. Immunogenicity was assessed at baseline, at 7 and 28 d after vaccination. Anti-PT, anti-FHA, anti-PRN, anti-tetanus and anti-diphtheria IgG antibodies were assessed by ELISA. Anti-PT neutralizing antibodies were assessed also by CHO cell assay. Results: A total of 60 subjects (20 per each vaccine group) were enrolled and included in the safety analysis. Safety laboratory parameters, incidence of local and systemic post-immunization reactions during 7 d after vaccination and incidence of adverse events during one month after vaccination were similar in the 3 vaccine groups. One month after vaccination, seroresponse rates of anti-PT, anti-FHA and anti-PRN IgG antibodies exceeded 78% in all vaccine groups. The anti-PT IgG, anti-FHA IgG, and anti-PT neutralizing antibody geometric mean titers (GMTs) were significantly higher following immunization with BioNet's aP and BioNet's TdaP than Adacel® (P< 0.05). The anti-PRN IgG, anti-tetanus and anti-diphtheria GMTs at one month after immunization were comparable in all vaccine groups. All subjects had seroprotective titers of anti-tetanus and anti-diphtheria antibodies at baseline. Conclusion: In this first clinical study, PTgen-based BioNet's aP and TdaP vaccines showed a similar tolerability and safety profile to Adacel® and elicited significantly higher immune responses to PT and FHA.

Quality of life results from a phase 3 study of brentuximab vedotin consolidation following autologous haematopoietic stem cell transplant for persons with Hodgkin lymphoma

Brentuximab vedotin (BV) significantly improved progression-free survival in a phase 3 study in patients with relapsed or refractory Hodgkin lymphoma (RR-HL) post-autologous-haematopoietic stem cell transplant (auto-HSCT); we report the impact of BV on quality of life (QOL) from this trial. The European Quality of Life five dimensions questionnaire was administered at the beginning of each cycle, end of treatment, and every 3 months during follow-up; index value scores were calculated using the time trade-off (TTO) method for UK-weighted value sets. Questionnaire adherence during the trial was 87·5% (N = 329). In an intent-to-treat analysis, compared with placebo, TTO scores in the BV arm did not exceed the minimally important difference (MID) of 0·08 except at month 15 (-0·084; 95% confidence interval, -0·143 to -0·025). On-treatment index scores were similar between arms and did not reach the MID at any time point; mixed-effect modelling showed that BV treatment effect was not significant (P = 0·2127). BV-associated peripheral neuropathy did not meaningfully impact QOL. Utility scores for patients who progressed declined compared with those who did not; TTO scores between these patients exceeded the MID beginning at month 15. In conclusion, QOL decreased modestly with BV consolidation treatment in patients with RR-HL at high risk of relapse after auto-HSCT.

Lessons Learned From Enhancing Vaccine Pharmacovigilance Activities During PsA-TT Introduction in African Countries, 2010-2013

Background. The rollout of the group A meningococcal vaccine, PsA-TT, in Africa's meningitis belt countries represented the first introduction of a vaccine specifically designed for this part of the world. During the first year alone, the number of people who received the vaccine through mass vaccination campaigns was several hundredfold higher than that of subjects who participated in the closely monitored clinical trials. Implementation of a system to identify rare but potentially serious vaccine reactions was therefore a high priority in the design and implementation of those campaigns.

Methods. National authorities and their technical partners set up effective vaccine pharmacovigilance systems, including conducting active surveillance projects.

Results. Implementation of national expert advisory groups to review serious adverse events following immunization in all countries and active monitoring of conditions of interest in 3 early-adopter countries did not identify particular concerns with the safety profile of PsA-TT, which had already provided tremendous public health benefits.

Conclusions. Lessons learned from this experience will help to improve preparations for future vaccine introductions in resource-poor settings and capitalize on such efforts to advance vaccine safety systems in the future.

Antibody Persistence 1-5 Years Following Vaccination With MenAfriVac in African Children Vaccinated at 12-23 Months of Age

Background. Following mass vaccination campaigns in the African meningitis belt with group A meningococcal conjugate vaccine, MenAfriVac (PsA-TT), disease due to group A meningococci has nearly disappeared. Antibody persistence in healthy African toddlers was investigated.

Methods. African children vaccinated at 12–23 months of age with PsA-TT were followed for evaluation of antibody persistence up to 5 years after primary vaccination. Antibody persistence was evaluated by measuring group A serum bactericidal antibody (SBA) with rabbit complement and by a group A–specific IgG enzyme-linked immunosorbent assay (ELISA).

Results. Group A antibodies measured by SBA and ELISA were shown to decline in the year following vaccination and plateaued at levels significantly above baseline for up to 5 years following primary vaccination.

Conclusions. A single dose of PsA-TT induces long-term sustained levels of group A meningococcal antibodies for up to 5 years after vaccination.

Clinical Trials Registration. ISRTCN78147026.

Safety Monitoring in Group A Meningococcal Conjugate Vaccine Trials: Description, Challenges, and Lessons

BACKGROUND

The determination of the safety profile of any vaccine is critical to its widespread use in any population. In addition, the application of international guidelines to fit local context could be a challenging but important step toward obtaining quality safety data.

METHODS

In clinical studies of PsA-TT (MenAfriVac), safety was monitored immediately after vaccination, at 4-7 days for postimmunization local and systemic reactions, within 28 days for adverse events, and throughout the duration of study for serious adverse events. Initial and ongoing training of sites' staff were undertaken during the studies, and a data and safety monitoring board reviewed all the data during and after the studies.

RESULTS

The safety of PsA-TT was evaluated according to international standards despite obvious challenges in remote areas where these studies were conducted. These challenges included the need for uniformity of methods, timely reporting in the context of frequent communication problems, occurrence of seasonal diseases such as malaria and rotavirus diarrhea, and healthcare systems that required improvement.

CONCLUSIONS

The trials of PsA-TT highlighted the value of a robust vaccine development plan and design so that lessons learned in initial studies were incorporated into the subsequent ones, initial training and periodic retraining, strict monitoring of all procedures, and continuous channel of communication with all stakeholders that enabled the application of international requirements to local settings, with high quality of data.

Antibody Persistence at 1 and 4 Years Following a Single Dose of MenAfriVac or Quadrivalent Polysaccharide Vaccine in Healthy Subjects Aged 2-29 Years

BACKGROUND

Mass vaccination campaigns of the population aged 1-29 years with 1 dose of group A meningococcal (MenA) conjugate vaccine (PsA-TT, MenAfriVac) in African meningitis belt countries has resulted in the near-disappearance of MenA. The vaccine was tested in clinical trials in Africa and in India and found to be safe and highly immunogenic compared with the group A component of the licensed quadrivalent polysaccharide vaccine (PsACWY). Antibody persistence in Africa and in India was investigated.

METHODS

A total of 900 subjects aged 2-29 years were followed up for 4 years in Senegal, Mali, and The Gambia (study A). A total of 340 subjects aged 2-10 years were followed up for 1 year in India (study B). In study A, subjects were randomized in a 2:1 ratio, and in study B a 1:1 ratio to receive either PsA-TT or PsACWY. Immunogenicity was evaluated by measuring MenA serum bactericidal antibody (SBA) with rabbit complement and by a group A-specific immunoglobulin G (IgG) enzyme-linked immunosorbent assay.

RESULTS

In both studies, substantial SBA decay was observed at 6 months postvaccination in both vaccine groups, although more marked in the PsACWY group. At 1 year and 4 years (only for study A) postvaccination, SBA titers were relatively sustained in the PsA-TT group, whereas a slight increasing trend, more pronounced among the youngest, was observed in the participants aged <18 years in the PsACWY groups. The SBA titers were significantly higher in the PsA-TT group than in the PsACWY group at any time point, and the majority of subjects in the PsA-TT group had SBA titers ≥128 and group A-specific IgG concentrations ≥2 µg/mL at any point in time in both the African and Indian study populations.

CONCLUSIONS

Four years after vaccination with a single dose of PsA-TT vaccine in Africa, most subjects are considered protected from MenA disease.

CLINICAL TRIALS REGISTRATION

PsA-TT-003 (ISRCTN87739946); PsA-TT-003a (ISRCTN46335400).

Ethical Challenges and Lessons Learned During the Clinical Development of a Group A Meningococcal Conjugate Vaccine

BACKGROUND

The group A meningococcal vaccine (PsA-TT) clinical development plan included clinical trials in India and in the West African region between 2005 and 2013. During this period, the Meningitis Vaccine Project (MVP) accumulated substantial experience in the ethical conduct of research to the highest standards.

METHODS

Because of the public-private nature of the sponsorship of these trials and the extensive international collaboration with partners from a diverse setting of countries, the ethical review process was complex and required strategic, timely, and attentive communication to ensure the smooth review and approval for the clinical studies. Investigators and their site teams fostered strong community relationships prior to, during, and after the studies to ensure the involvement and the ownership of the research by the participating populations. As the clinical work proceeded, investigators and sponsors responded to specific questions of informed consent, pregnancy testing, healthcare, disease prevention, and posttrial access.

RESULTS

Key factors that led to success included (1) constant dialogue between partners to explore and answer all ethical questions; (2) alertness and preparedness for emerging ethical questions during the research and in the context of evolving international ethics standards; and (3) care to assure that approaches were acceptable in the diverse community contexts.

CONCLUSIONS

Many of the ethical issues encountered during the PsA-TT clinical development are familiar to groups conducting field trials in different cultural settings. The successful approaches used by the MVP clinical team offer useful examples of how these problems were resolved.

CLINICAL TRIALS REGISTRATION

ISRCTN17662153 (PsA-TT-001); ISRTCN78147026 (PsA-TT-002); ISRCTN87739946 (PsA-TT-003); ISRCTN46335400 (PsA-TT-003a); ISRCTN82484612 (PsA-TT-004); CTRI/2009/091/000368 (PsA-TT-005); PACTR ATMR2010030001913177 (PsA-TT-006); PACTR201110000328305 (PsA-TT-007).

Dengue epidemiology in selected endemic countries: factors influencing expansion factors as estimates of underreporting

OBJECTIVE

Dengue fever is globally considered underestimated. This study provides expansion factors (EFs) for dengue endemic selected countries and highlights critical issues in the use of EFs.

METHODS

We identified dengue epidemiological cohort studies from 2000 to July 2013 through a literature search using PubMed, Web of Science and Lilacs (Latin American and Caribbean Health Sciences Database), pre-defined keywords and inclusion/exclusion criteria, and included Brazil, Colombia, Nicaragua, Peru, Puerto Rico, Venezuela, Bangladesh, Cambodia, India, Indonesia, Philippines, Singapore, Sri Lanka, Thailand and Vietnam. Dengue national and local passive surveillance data were derived from WHO regional websites, PAHO, SEARO and WPRO. EFs were calculated as CI cohort studies/CI passive data for both national and local levels.

RESULTS

Cohort studies differed in case definition, laboratory test used and surveillance methods. The information on SEARO, PAHO and WPRO websites differed in terms of dengue epidemiological variables, population denominators and completeness. The highest incidence was reported by PAHO countries followed by WPRO and SEARO countries. EFs may vary for the different variables and denominators used for calculation. EFs were the highest in SEARO countries and lowest in PAHO countries. A trend for lower local EFs was observed.

CONCLUSIONS

The use of EFs for quantifying dengue underreporting may be problematic due to lack of uniformity in reporting dengue both active and passive surveillance data. Quality dengue surveillance data are urgently needed for a better estimate of dengue disease burden and to measure the impact of preventive intervention.

Safety and efficacy of single-agent bendamustine after failure of brentuximab vedotin in patients with relapsed or refractory hodgkin's lymphoma: experience with 27 patients

BACKGROUND

The optimal treatment of patients with heavily pretreated Hodgkin's lymphoma is controversial. Brentuximab vedotin is an active single agent in this context. Also, bendamustine can be regarded as a safe and effective alternative for patients with relapse after autologous transplantation and as an interesting cytoreductive strategy before allogeneic transplantation.

PATIENTS AND METHODS

An observational, multicenter, retrospective study is reported of single-agent bendamustine in 27 heavily pretreated patients with relapsed or refractory Hodgkin's lymphoma, who had all received brentuximab vedotin as their last treatment and who showed disease progression, refractory disease, or early relapse. The primary study endpoint was the objective response rate, and the secondary endpoint was the safety of the bendamustine regimen.

RESULTS

The overall response rate was 55.5%, with 10 of 27 patients (37.0%) obtaining a complete response. In comparison, the overall response rate previously observed with brentuximab vedotin in the same subset of patients was much lower (18.5%). Among the 10 patients with a complete response after bendamustine, only 1 had had a complete response to brentuximab, with 2 having a partial response and 7 stable or progressive disease. With a median duration of response of 8 months, all these patients had maintained a continuous response at the last follow-up examination. The treatment was well tolerated, with rather infrequent adverse events and transient and manageable toxicities.

CONCLUSION

Albeit with the limits of an observational retrospective study, these data indicate that bendamustine shows its efficacy in patients already treated with brentuximab vedotin, regardless of their previously obtained response and without any significant toxicity.

Brentuximab vedotin in patients with Hodgkin lymphoma and a failed allogeneic stem cell transplantation: results from a named patient program at four Italian centers

BACKGROUND

Brentuximab vedotin (BV) has demonstrated an extraordinary efficacy in heavily pretreated classical Hodgkin lymphoma (cHL) patients, targeting CD30-positive cells; however, limited data have been reported on the efficacy of BV in cHL patients failing allogeneic stem cell transplantation (allo-SCT). The aim of this study was to retrospectively evaluate the efficacy and safety of BV in a multicenter setting of cHL relapsing or progressing after allo-SCT.

METHODS

Sixteen BV-naïve patients with recurrent cHL after allo-SCT were included in a compassionate use program and treated with intravenous BV at the dose of 1.8 mg/kg of body weight every 3 weeks for a maximum of 16 cycles.

RESULTS

The objective response rate was 69%. Five patients (31%) had complete remission, and 6 (37%) had partial remission. Stable disease was observed in 4 patients (25%), and progressive disease was observed in 1 (6%). After median follow-up of 26 months (range: 5-30 months), median progression-free survival (PFS), overall survival (OS), and duration of response were 7, 25, and 5 months, respectively. The 2-year PFS and OS were 20% and 61%, respectively. Grade 3-4 hematological adverse events included anemia (15%), thrombocytopenia (12%), and neutropenia (18%). Grade 3 peripheral sensory neuropathy occurred in 2 patients (12%).

CONCLUSION

BV therapy is an effective and safe approach for achieving transient disease control in cHL patients with failed allo-SCT. To improve disease control, future studies should explore the combination of BV with targeted agents.