Sodium content in processed food items in Sweden compared to other countries: a cross-sectional multinational study.

Background: Dietary sodium has a dose-response relationship with cardiovascular disease, and sodium intake in Sweden exceeds national and international recommendations. Two thirds of dietary sodium intake comes from processed foods, and adults in Sweden eat more processed foods than any other European country. We hypothesized that sodium content in processed foods is higher in Sweden than in other countries. The aim of this study was to investigate sodium content in processed food items in Sweden, and how it differs from Australia, France, Hong Kong, South Africa, the United Kingdom and the United States. Methods: Data were collected from retailers by trained research staff using standardized methods. Data were categorized into 10 food categories and compared using Kruskal-Wallis test of ranks. Sodium content in the food items was compared in mg sodium per 100 g of product, based on the nutritional content labels on the packages. Results: Compared to other countries, Sweden had among the highest sodium content in the "dairy" and "convenience foods" categories, but among the lowest in "cereal and grain products," "seafood and seafood products" and "snack foods" categories. Australia had the overall lowest sodium content, and the US the overall highest. The highest sodium content in most analyzed countries was found in the "meat and meat products" category. The highest median sodium content in any category was found among "sauces, dips, spreads and dressings" in Hong Kong. Conclusion: The sodium content differed substantially between countries in all food categories, although contrary to our hypothesis, processed foods overall had lower sodium content in Sweden than in most other included countries. Sodium content in processed food was nonetheless high also in Sweden, and especially so in increasingly consumed food categories, such as "convenience foods".

INEXAS: A Phase 2 Randomized Trial of On-demand Inhaled Interferon Beta-1a in Severe Asthmatics.

BACKGROUND: Upper respiratory tract infections (URTIs) are important triggers for asthma exacerbations. We hypothesized that inhalation of the anti-viral cytokine, interferon (IFN)-ß, during URTI, could prevent these exacerbations. OBJECTIVE: To evaluate the efficacy of on-demand inhaled IFN-ß1a (AZD9412) to prevent severe asthma exacerbations following symptomatic URTI. METHODS: This was a randomized, double-blind, placebo-controlled trial in which patients with severe asthma (GINA 4-5; n = 121) reporting URTI symptoms were randomized to 14 days of once-daily nebulized AZD9412 or placebo. The primary endpoint was severe exacerbations during treatment. Secondary endpoints included 6-item asthma control questionnaire (ACQ-6) and lung function. Exploratory biomarkers included IFN-response markers in serum and sputum, blood leucocyte counts and serum inflammatory cytokines. RESULTS: Following a pre-planned interim analysis, the trial was terminated early due to an unexpectedly low exacerbation rate. Asthma worsenings were generally mild and tended to peak at randomization, possibly contributing to the lack of benefit of AZD9412 on other asthma endpoints. Numerically, AZD9412 did not reduce severe exacerbation rate, ACQ-6, asthma symptom scores or reliever medication use. AZD9412 improved lung function (morning peak expiratory flow; mPEF) by 19.7 L/min. Exploratory post hoc analyses indicated a greater mPEF improvement by AZD9412 in patients with high blood eosinophils (>0.3 × 109 /L) at screening and low serum interleukin-18 relative change at pre-treatment baseline. Pharmacodynamic effect of AZD9412 was confirmed using IFN-response markers. CONCLUSIONS & CLINICAL RELEVANCE: Colds did not have the impact on asthma patients that was expected and, due to the low exacerbation rate, the trial was stopped early. On-demand AZD9412 treatment did not numerically reduce the number of exacerbations, but did attenuate URTI-induced worsening of mPEF. Severe asthma patients with high blood eosinophils or low serum interleukin-18 response are potential subgroups for further investigation of inhaled IFN-ß1a.

Acalabrutinib with or without obinutuzumab versus chlorambucil and obinutuzmab for treatment-naive chronic lymphocytic leukaemia (ELEVATE TN): a randomised, controlled, phase 3 trial.

BACKGROUND: Acalabrutinib is a selective, covalent Bruton tyrosine-kinase inhibitor with activity in chronic lymphocytic leukaemia. We compare the efficacy of acalabrutinib with or without obinutuzumab against chlorambucil with obinutuzumab in patients with treatment-naive chronic lymphocytic leukaemia. METHODS: ELEVATE TN is a global, phase 3, multicentre, open-label study in patients with treatment-naive chronic lymphocytic leukaemia done at 142 academic and community hospitals in 18 countries. Eligible patients had untreated chronic lymphocytic leukaemia and were aged 65 years or older, or older than 18 years and younger than 65 years with creatinine clearance of 30-69 mL/min (calculated by use of the Cockcroft-Gault equation) or Cumulative Illness Rating Scale for Geriatrics score greater than 6. Additional criteria included an Eastern Cooperative Oncology Group performance status score of 2 or less and adequate haematologic, hepatic, and renal function. Patients with significant cardiovascular disease were excluded, and concomitant treatment with warfarin or equivalent vitamin K antagonists was prohibited. Patients were randomly assigned (1:1:1) centrally via an interactive voice or web response system to receive acalabrutinib and obinutuzumab, acalabrutinib monotherapy, or obinutuzumab and oral chlorambucil. Treatments were administered in 28-day cycles. To reduce infusion-related reactions, acalabrutinib was administered for one cycle before obinutuzumab administration. Oral acalabrutinib was administered (100 mg) twice a day until progressive disease or unacceptable toxic effects occurred. In the acalabrutinib-obinutuzumab group, intravenous obinutuzumab was given on days 1 (100 mg), 2 (900 mg), 8 (1000 mg), and 15 (1000 mg) of cycle 2 and on day 1 (1000 mg) of cycles 3-7. In the obinutuzumab-chlorambucil group, intravenous obinutuzumab was given on days 1 (100 mg), 2 (900 mg), 8 (1000 mg), and 15 (1000 mg) of cycle 1 and on day 1 (1000 mg) of cycles 2-6. Oral chlorambucil was given (0·5 mg/kg) on days 1 and 15 of each cycle, for six cycles. The primary endpoint was progression-free survival between the two combination-therapy groups, assessed by independent review committee. Crossover to acalabrutinib was allowed in patients who progressed on obinutuzumab-chlorambucil. Safety was assessed in all patients who received at least one dose of treatment. Enrolment for this trial is complete, and the study is registered at ClinicalTrials.gov, NCT02475681. FINDINGS: Between Sept 14, 2015, and Feb 8, 2017, we recruited 675 patients for assessment. 140 patients did not meet eligibility criteria, and 535 patients were randomly assigned to treatment. 179 patients were assigned to receive acalabrutinib-obinutuzumab, 179 patients were assigned to receive acalabrutinib monotherapy, and 177 patients were assigned to receive obinutuzumab-chlorambucil. At median follow-up of 28·3 months (IQR 25·6-33·1), median progression-free survival was longer with acalabrutinib-obinutuzumab and acalabrutinib monotherapy, compared with obinutuzumab-chlorambucil (median not reached with acalabrutinib and obinutuzumab vs 22·6 months with obinutuzumab, hazard ratio [HR] 0·1; 95% CI 0·06-0·17, p<0·0001; and not reached with acalabrutinib monotherapy vs 22·6 months with obinutuzumab, 0·20; 0·13-0·3, p<0·0001). Estimated progression-free survival at 24 months was 93% with acalabrutinib-obinutuzumab (95% CI 87-96%), 87% with acalabrutinib monotherapy (81-92%), and 47% with obinutuzumab-chlorambucil (39-55%). The most common grade 3 or higher adverse event across groups was neutropenia (53 [30%] of 178 patients in the acalabrutinib-obinutuzumab group, 17 [9%] of 179 patients in the acalabrutinib group, and 70 [41%] of 169 patients in the obinutuzumab-chlorambucil group). All-grade infusion reactions were less frequent with acalabrutinib-obinutuzumab (24 [13%] of 178 patients) than obinutuzumab-chlorambucil (67 [40%] of 169 patients). Grade 3 or higher infections occurred in 37 (21%) patients given acalabrutinib-obinutuzumab, 25 (14%) patients given acalabrutinib monotherapy, and 14 (8%) patients given obinutuzumab-chlorambucil. Deaths occurred in eight (4%) patients given acalabrutinib-obinutuzumab, 12 (7%) patients given acalabrutinib, and 15 (9%) patients given obinutuzumab-chlorambucil. INTERPRETATION: Acalabrutinib with or without obinutuzumab significantly improved progression-free survival over obinutuzumab-chlorambucil chemoimmunotherapy, providing a chemotherapy-free treatment option with an acceptable side-effect profile that was consistent with previous studies. These data support the use of acalabrutinib in combination with obinutuzumab or alone as a new treatment option for patients with treatment-naive symptomatic chronic lymphocytic leukaemia. FUNDING: Acerta Pharma, a member of the AstraZeneca Group, and R35 CA198183 (to JCB).

Introducing patient-reported outcome in the acute leukemia quality registries in Sweden.

OBJECTIVES: The use of patient-reported outcome (PRO) measured outside clinical trials is not well defined. We report the first analysis of the prospective PRO study within the Swedish acute myeloid leukemia (AML) and the acute lymphoblastic leukemia (ALL) registries. METHODS: PRO was requested 6 months after diagnosis. The EORTC Quality of life Questionnaire Core 30-item, the Patient Health Questionnaire-8 (PHQ-8), and questions from a Swedish National Cancer Questionnaire were used. RESULTS: An invitation letter was sent to 398 patients; 255 (64%) responded, 60% web-based, and 40% on paper. The ALL cohort had lower physical, role and social functioning, higher symptom burden, and more financial difficulties compared to the AML cohort. A PHQ-8 score ≥ 10p, which indicates depression, was reported in 18% of the patients; 33% of these patients reported being prescribed antidepressants. The patients' overall experience of care was satisfying, but more psychological and practical support was desired. There was no difference in survival between patients who reported their PRO and those who did not. Follow-up at 2 and 4 years is ongoing. CONCLUSIONS: PRO collected in a registry-based setting is feasible, but the selection of time points and questionnaires are delicate in a diverse patient population.

Preceptors' and nursing students' experiences of peer learning in a psychiatric context: A qualitative study.

OBJECTIVE: The aim of this study was to investigate preceptors' and nursing students' experiences of peer learning in a psychiatric context during their clinical education. DESIGN: A qualitative research design was used in this study. Data were analysed with qualitative content analysis. The study was conducted in 2017 with 17 preceptors and 11 students, constituting four focus groups with preceptors and four focus groups with nursing students. PARTICIPANTS: The preceptors were nurses and specialist nurses who worked in inpatient psychiatric care. Nursing students seeking their bachelor's degrees were placed in clinical settings at different psychiatric units for 4 weeks during the fourth semester. RESULTS: One theme emerged: Knowledge acquisition as an interactive process from the two shared categories for students and preceptors: the importance of a supportive relationship and reciprocal learning by communication, doing and reflection. CONCLUSIONS: The result of this study suggested that peer learning in clinical education in psychiatric care promoted the learning process for nursing students.

Survival in adult acute lymphoblastic leukaemia (ALL): A report from the Swedish ALL Registry.

OBJECTIVES: As new, effective therapies emerge for acute lymphoblastic leukaemia (ALL), the results of clinical trials need to relate to standard of care. METHODS: We used the population-based Swedish ALL Registry to evaluate characteristics, treatment and long-term outcome in 933 patients with diagnosis between 1997 and 2015. RESULTS: The median age was 53 years. The frequency of Philadelphia (Ph)-positive leukaemia was 34% of examined B-ALL with a peak incidence at 50-59 years. Five-year overall survival (OS) improved between 1997-2006 and 2007-2015; in patients 18-45 years from 50% (95% CI 43-57) to 65% (95% CI 58-72), 46-65 years from 25% (95% CI 18-32) to 46% (95% CI 37-55) and >65 years from 7% (95% CI 2.6-11) to 11% (95% CI 5.9-16) (P < 0.05). Men with Ph-neg B-ALL 46-65 years had inferior OS compared with women (P < 0.01). Standardised mortality ratio was 5.7 (95% CI 5.0-6.3) for patients who survived 5 years from diagnosis. In multivariable analysis, Ph-positive disease was not associated with impaired prognosis but with lower risk of death in 2007-2015. CONCLUSIONS: In a population-based cohort, OS has improved in adult ALL, especially for Ph-positive disease but for middle-aged men with Ph-negative B-ALL outcome was poor. Cure without late toxicity or relapse is still desired.

First-line therapy in chronic lymphocytic leukemia: a Swedish nation-wide real-world study on 1053 consecutive patients treated between 2007 and 2013.

The aim of this study was to investigate long-term outcome following first-line therapy in consecutive chronic lymphocytic leukemia (CLL) patients in a well-defined geographic area: Sweden. All patients diagnosed with CLL (2007-2013) (n=3672) were identified from national registries, screening of patient files identified all (100%) treated first line (n=1053) and for those, an in-depth analysis was performed. End points were overall response rate, progression-free survival (PFS), overall survival (OS), and safety. Median age was 71 years; 53% had Rai stage III-IV and 97% had performance status grade 0-2. Fluorescence in situ hybridization (FISH) was performed in 57% of patients: 15% had del(17p). Chlorambucil + prednisone was used in 39% (5% also received rituximab). Fludarabine+cyclophosphamide+rituximab or fludarabine+cyclophosphamide was used in 43% and bendamustine + rituximab in 6%. Overall response rate was 64%; chlorambucil 43%, fludarabine+cyclophosphamide+rituximab 84%, fludarabine+cyclophosphamide 75% and bendamustine + rituximab 75%. Median PFS and OS was 24 and 58 months, respectively, both were significantly associated (multivariate analysis) with type of treatment, del(17p), performance status, gender, age and geographical region (OS only). Chlorambucil-treated patients had a median PFS and OS of only 9 and 33 months, respectively. Chlorambucil usage declined gradually throughout the study period, but one-third of patients still received chlorambucil + rituximab in 2013. Infections ≥grade III were significantly associated with treatment; chlorambucil 19% versus fludarabine+cyclophosphamide+rituximab 30%. Richter transformation occurred in 5.5% of the patients, equally distributed across therapies. This is the largest retrospective, real-world cohort of consecutive first-line treated CLL patients with a complete follow up. In elderly patients, an unmet need for more effective, well-tolerated therapies was identified.

Age but not Philadelphia positivity impairs outcome in older/elderly patients with acute lymphoblastic leukemia in Sweden.

OBJECTIVES: Older/elderly patients with acute lymphoblastic leukemia (ALL) are poorly represented in clinical trials. METHODS: Using Swedish national leukemia registries, we investigated disease/patient characteristics, treatment choices, outcome, and the impact of an age-adapted protocol (introduced in 2009) in this population-based study of patients aged 55-85 years, diagnosed with ALL 2005-2012. RESULTS: Of 174 patients, 82% had B-phenotype, 11% Burkitt leukemia (excluded), and 7% T-phenotype. Philadelphia chromosome positivity (Ph+) occurred in 35%. Of the 155 B- and T-ALL patients, 80% were treated with intensive protocols, and 20% with a palliative approach. Higher age and WHO performance status ≥2 influenced the choice of palliation. Intensive, palliative, and both approaches resulted in complete remission rate 83/16/70% and 3-year overall survival (OS) 32/3/26%. The age-adapted protocol did not improve outcome. With intensive treatment, platelet count ≤35×109 /L and age ≥75 years were adverse prognostic factors for OS, Ph+ was not. Male sex was an adverse prognostic factor in the 55-64 year age-group. CONCLUSIONS: We report a high frequency of Ph+ in older/elderly patients, with no evidence of poorer outcome compared to Ph-negative disease. Overall prognosis for elderly patients with ALL remains dismal, despite the use of age-adapted treatment.

Real-world results of ibrutinib in patients with relapsed or refractory chronic lymphocytic leukemia: data from 95 consecutive patients treated in a compassionate use program. A study from the Swedish Chronic Lymphocytic Leukemia Group.

Ibrutinib, a Bruton's tyrosine kinase inhibitor is approved for relapsed/refractory and del(17p)/TP53 mutated chronic lymphocytic leukemia. Discrepancies between clinical trials and routine health-care are commonly observed in oncology. Herein we report real-world results for 95 poor prognosis Swedish patients treated with ibrutinib in a compassionate use program. Ninety-five consecutive patients (93 chronic lymphocytic leukemia, 2 small lymphocytic leukemia) were included in the study between May 2014 and May 2015. The median age was 69 years. 63% had del(17p)/TP53 mutation, 65% had Rai stage III/IV, 28% had lymphadenopathy ≥10cm. Patients received ibrutinib 420 mg once daily until progression. At a median follow-up of 10.2 months, the overall response rate was 84% (consistent among subgroups) and 77% remained progression-free. Progression-free survival and overall survival were significantly shorter in patients with del(17p)/TP53 mutation (P=0.017 and P=0.027, log-rank test); no other factor was significant in Cox proportional regression hazards model. Ibrutinib was well tolerated. Hematomas occurred in 46% of patients without any major bleeding. Seven patients had Richter's transformation. This real-world analysis on consecutive chronic lymphocytic leukemia patients from a well-defined geographical region shows the efficacy and safety of ibrutinib to be similar to that of pivotal trials. Yet, del(17p)/TP53 mutation remains a therapeutic challenge. Since not more than half of our patients would have qualified for the pivotal ibrutinib trial (RESONATE), our study emphasizes that real-world results should be carefully considered in future with regards to new agents and new indications in chronic lymphocytic leukemia.

Virtual patient simulation in psychiatric care - A pilot study of digital support for collaborate learning.

Psychiatric and mental health nursing is built on a trusted nurse and patient relationship. Therefore communication and clinical reasoning are two important issues. Our experiences as teachers in psychiatric educational programmes are that the students feel anxiety and fear before they start their clinical practices in psychiatry. Therefore there is a need for bridging over the fear. Technology enhanced learning might support such activities so we used Virtual patients (VPs), an interactive computer simulations of real-life clinical scenarios. The aim of this study was to investigate 4th term nursing students' opinions on the use of Virtual Patients for assessment in a Mental Health and Ill-health course module. We asked 24 volunteering students to practise with five different VP cases during almost 10 weeks before the exam. The participants were gathered together for participating in a written and an oral evaluation. The students were positive to the use of VPs in psychiatry and were very positive to use VPs in their continued nursing education. It seems that Virtual Patients can be an activity producing pedagogic model promoting students' independent knowledge development, critical thinking, reflection and problem solving ability for nurse students in psychiatric care.

Satisfactory outcome after intensive chemotherapy with pragmatic use of minimal residual disease (MRD) monitoring in older patients with Philadelphia-negative B cell precursor acute lymphoblastic leukaemia: a Swedish registry-based study.

The introduction of minimal residual disease (MRD) monitoring, in the Swedish national guidelines for acute lymphoblastic leukaemia, was evaluated in 35 patients aged 46-79 years (median 61), who were diagnosed from 2007 to 2011 and treated with high-intensity, block-based chemotherapy (ABCDV/VABA induction). Both a high complete remission rate (91 %) and acceptable overall survival (OS) rate (47 %) at 5 years were achieved. MRD by flow cytometry was measured in 73 % of the patients reaching complete remission after the first course, but was omitted by the clinicians for eight patients who were either over 70 years of age or already met conventional high-risk criteria. Factors negatively influencing OS were age over 65 years and WHO status ≥2. MRD < 0.1 % after induction had positive impact on continuous complete remission but not on OS. Only five patients were allocated to allogeneic haematopoietic stem cell transplantation in first remission, mainly due to conventional high risk factors. Thus, use of intensive remission induction therapy is effective in a selection of older patients. In a population for whom the possibilities of treatment escalation are limited, the optimal role of MRD monitoring remains to be determined.

Novel gene targets detected by genomic profiling in a consecutive series of 126 adults with acute lymphoblastic leukemia.

In contrast to acute lymphoblastic leukemia in children, adult cases of this disease are associated with a very poor prognosis. In order to ascertain whether the frequencies and patterns of submicroscopic changes, identifiable with single nucleotide polymorphism array analysis, differ between childhood and adult acute lymphoblastic leukemia, we performed single nucleotide polymorphism array analyses of 126 adult cases, the largest series to date, including 18 paired diagnostic and relapse samples. Apart from identifying characteristic microdeletions of the CDKN2A, EBF1, ETV6, IKZF1, PAX5 and RB1 genes, the present study uncovered novel, focal deletions of the BCAT1, BTLA, NR3C1, PIK3AP1 and SERP2 genes in 2-6% of the adult cases. IKZF1 deletions were associated with B-cell precursor acute lymphoblastic leukemia (P=0.036), BCR-ABL1-positive acute lymphoblastic leukemia (P<0.001), and higher white blood cell counts (P=0.005). In addition, recurrent deletions of RASSF3 and TOX were seen in relapse samples. Comparing paired diagnostic/relapse samples revealed identical changes at diagnosis and relapse in 27%, clonal evolution in 22%, and relapses evolving from ancestral clones in 50%, akin to what has previously been reported in pediatric acute lymphoblastic leukemia and indicating that the mechanisms of relapse may be similar in adult and childhood cases. These findings provide novel insights into the leukemogenesis of adult acute lymphoblastic leukemia, showing similarities to childhood disease in the pattern of deletions and the clonal relationship between diagnostic and relapse samples, but with the adult cases harboring additional aberrations that have not been described in pediatric acute lymphoblastic leukemia.

Cladribine prolongs progression-free survival and time to second treatment compared to fludarabine and high-dose chlorambucil in chronic lymphocytic leukemia.

We conducted a randomized phase III trial to compare the efficacy and safety of two purine analogs, cladribine and fludarabine, with high-dose chlorambucil, in patients with previously untreated chronic lymphocytic leukemia (CLL). Between 1997 and 2004, 223 patients with CLL were randomly assigned to cladribine, fludarabine or chlorambucil, for six cycles of therapy with frequent health-related quality of life assessments. There was no statistical difference for the primary endpoint of overall response with cladribine (70%), fludarabine (67%) and chlorambucil (59%), or complete remission (12%, 7% and 8%), respectively. However, the median progression-free survival (25, 10, 9 months) and median time to second treatment (40, 22, 21 months) were superior with cladribine. There was no significant difference in overall survival (96, 82 and 91 months), nor in toxicity or HRQoL assessments. Monotherapy with cladribine gives superior PFS and longer response duration than fludarabine and chlorambucil as first-line treatment of CLL.

High relapse rate of T cell acute lymphoblastic leukemia in adults treated with Hyper-CVAD chemotherapy in Sweden.

BACKGROUND: Hyper-CVAD is widely used to treat acute lymphoblastic leukemia (ALL) and aggressive lymphomas. This multicenter, population-based study assessed the efficacy of Hyper-CVAD as first-line therapy in patients with T-cell ALL (T-ALL). PATIENTS AND METHODS: Between October 2002 and September 2006, 24 patients were diagnosed with T-ALL in Sweden; 19 were eligible for treatment with the protocol. RESULTS: The median age was 32 yr (range 18-72 yr). Complete remission (CR) was obtained in 17 of 19 (89%) patients, and the treatment was relatively well tolerated. Allogeneic stem cell transplantation (SCT) was recommended in high-risk disease and was performed in four patients upfront. Two- and 5-yr leukemia-free survivals (LFS) in 17 patients with CR achievement were identical, at 29% (95% confidence interval [CI]: 8-51). Two- and 5-yr overall survival (OS) in whole cohort was 63% (95% CI: 42-85) and 47% (95% CI: 26-69), respectively. The 5-yr LFS for 15 patients who did not receive allogeneic SCT upfront were 20% (95% CI: 0-40), although 14 of 15 completed the protocol (eight cycles). Relapse occurred in 2 of 4 upfront-transplanted patients and in 12 of 15 patients treated with chemotherapy alone, six of whom received allogeneic SCT in CR2. Age ≥35 yr influenced OS negatively in univariate analysis (HR 5.1, 95% CI: 1.55-16.7). CONCLUSIONS: Hyper-CVAD treatment resulted in a high CR rate and appeared safe, but it showed poor efficacy at preventing relapse. Therefore, this treatment is no longer recommended for adults with T-ALL in Sweden.

Matrix-M™ adjuvanted envelope protein vaccine protects against lethal lineage 1 and 2 West Nile virus infection in mice.

West Nile virus (WNV) is a mosquito-transmitted flavivirus and an emerging pathogen in many parts of the world. In the elderly and immunosuppressed, infection can progress rapidly to debilitating and sometimes fatal neuroinvasive disease. Currently, no WNV vaccine is approved for use in humans. As there have been several recent outbreaks in the United States and Europe, there is an increasing need for a human WNV vaccine. In this study, we formulated the ectodomain of a recombinant WNV envelope (E) protein with the particulate saponin-based adjuvant Matrix-M™ and studied the antigen-specific immune responses in mice. Animals immunized with Matrix-M™ formulated E protein developed higher serum IgG1 and IgG2a and neutralizing antibody titers at antigen doses ranging from 0.5 to 10 µg compared to those immunized with 3 or 10 µg of E alone, E adjuvanted with 1% Alum, or with the inactivated virion veterinary vaccine, Duvaxyn(®) WNV. This phenotype was accompanied by strong cellular recall responses as splenocytes from mice immunized with Matrix-M™ formulated vaccine produced high levels of Th1 and Th2 cytokines. Addition of Matrix-M™ prolonged the duration of the immune response, as elevated humoral and cellular responses were maintained for more than 200 days. Importantly, mice vaccinated with Matrix-M™ formulated E protein were protected from lethal challenge with both lineage 1 and 2 WNV strains. In summary, Matrix-M™ adjuvanted E protein elicited potent and durable immune responses that prevented lethal WNV infection, and thus is a promising vaccine candidate for humans.

Immune enhancing properties of the novel Matrix-M™ adjuvant leads to potentiated immune responses to an influenza vaccine in mice.

The novel saponin based adjuvant Matrix-M™ was recently used in a Phase I study of seasonal influenza in elderly. The present study is a pre-clinical evaluation of the efficacy and mode-of-action of Matrix-M™ formulated influenza vaccine in mice. A manuscript on safety profile and immunogenicity in elderly humans is under preparation. We have previously shown that subcutaneous injections of Matrix-M™, without coformulated antigen, results in a dose-dependent recruitment of leukocytes to draining lymph nodes (dLNs). Herein we compared the mode of action of Matrix-M™ with Alum, FCA and AS03 alone or formulated with influenza split virion antigen injected intramuscularly. The elicited responses in dLNs and spleen were investigated 48h later. Matrix-M™ was particularly efficient in activation of central innate immune cells such as neutrophils, DCs and macrophages compared to the other adjuvants analyzed. Moreover, the adjuvant influence on the recall immune response to influenza antigen was studied by in vitro re-stimulation of splenocytes from mice immunized with influenza antigen adjuvanted with Matrix-M™, Alum or AS03. Splenocytes from mice immunized with influenza antigen and Matrix-M™ produced both Th1 and Th2 cytokines upon re-stimulation. This response was significantly stronger than that induced by the other adjuvants studied. Interestingly, increased levels of the neutrophil chemoattractant KC were produced by antigen stimulated splenocytes from mice immunized with Matrix-M™ adjuvanted vaccine, which is in agreement with the increase of neutrophils into dLNs and spleen after Matrix-M™ injection. Furthermore, influenza antigen adjuvanted with Matrix-M™ induced significantly higher antigen-specific IgG1 and IgG2a responses compared to antigen alone. In conclusion, adjuvant Matrix-M™ activates the innate immune system without antigen present. This activation may explain the enhanced immunity to influenza seen with Matrix-M™ adjuvant. Despite this potent immune activation mediated by Matrix-M™, GLP-toxicity studies and clinical data suggest that Matrix-M™ adjuvant has a mild to moderate safety profile.