LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 7 of total 7

Search options

  1. Article ; Online: Impact of treatment and re-treatment with artemether-lumefantrine and artesunate-amodiaquine on selection of Plasmodium falciparum multidrug resistance gene-1 polymorphisms in the Democratic Republic of Congo and Uganda.

    Vito Baraka / Hypolite Muhindo Mavoko / Carolyn Nabasumba / Filbert Francis / Pascal Lutumba / Michael Alifrangis / Jean-Pierre Van Geertruyden

    PLoS ONE, Vol 13, Iss 2, p e

    2018  Volume 0191922

    Abstract: The emergence of resistance against artemisinin combination treatment is a major concern for malaria control. ACTs are recommended as the rescue treatment, however, there is limited evidence as to whether treatment and re-treatment with ACTs select for ... ...

    Abstract The emergence of resistance against artemisinin combination treatment is a major concern for malaria control. ACTs are recommended as the rescue treatment, however, there is limited evidence as to whether treatment and re-treatment with ACTs select for drug-resistant P. falciparum parasites. Thus, the purpose of the present study is to investigate the impact of (re-)treatment using artesunate-amodiaquine (ASAQ) and artemether-lumefantrine (AL) on the selection of P. falciparum multidrug resistance-1 (Pfmdr1) alleles in clinical settings.P. falciparum positive samples were collected from children aged 12-59 months in a clinical trial in DR Congo and Uganda. Pfmdr1 single nucleotide polymorphisms (SNPs) analysis at codons N86Y, Y184F, and D1246Y were performed at baseline and post-treatment with either AL or ASAQ as a rescue treatment using nested PCR followed by restriction fragment length polymorphism (RFLP) assays.The pre-treatment prevalence of Pfmdr1 N86 and D1246Y varied significantly between the sites, (p>0.001) and (p = 0.013), respectively. There was borderline significant directional selection for Pfmdr1 184F in recurrent malaria infections after treatment with AL in Uganda site (p = 0.05). Pfmdr1 NFD haplotype did not significantly change in post-treatment infections after re-treatment with either AL or ASAQ. Comparison between pre-treatment and post-treatment recurrences did not indicate directional selection of Pfmdr1 N86, D1246 alleles in the pre-RCT, RCT and post-RCT phases in both AL and ASAQ treatment arms. Pfmdr1 86Y was significantly associated with reduced risk of AL treatment failure (RR = 0.34, 95% CI:0.11-1.05, p = 0.04) while no evidence for D1246 allele (RR = 1.02; 95% CI: 0.42-2.47, p = 1.0). Survival estimates showed that the Pfmdr1 alleles had comparable mean-time to PCR-corrected recrudescence and new infections in both AL and ASAQ treatment arms.We found limited impact of (re-)treatment with AL or ASAQ on selection for Pfmdr1 variants and haplotypes associated with resistance to partner drugs. These findings further supplement the evidence use of same or alternative ACTs as a rescue therapy for recurrent P.falciparum infections. Continued monitoring of genetic signatures of resistance is warranted to timely inform malaria (re-)treatment policies and guidelines.
    Keywords Medicine ; R ; Science ; Q
    Subject code 616
    Language English
    Publishing date 2018-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  2. Article ; Online: Performance and time to become negative after treatment of three malaria rapid diagnostic tests in low and high malaria transmission settings

    Francesco Grandesso / Carolyn Nabasumba / Dan Nyehangane / Anne-Laure Page / Mathieu Bastard / Martin De Smet / Yap Boum / Jean-François Etard

    Malaria Journal, Vol 15, Iss 1, Pp 1-

    2016  Volume 12

    Abstract: Abstract Background The performance of different malaria rapid diagnostic tests (RDT) may be influenced by transmission intensity and by the length of time each test requires to become negative after treatment and patient’s recovery. Methods Results of ... ...

    Abstract Abstract Background The performance of different malaria rapid diagnostic tests (RDT) may be influenced by transmission intensity and by the length of time each test requires to become negative after treatment and patient’s recovery. Methods Results of three RDTs (two HRP2 and one pLDH antigen-based tests) were compared to blood smear microscopy (the gold standard method) in children under 5 years of age living in a high versus low malaria intensity setting in southwestern Uganda. In each setting, 212 children, who tested positive by at least one RDT and by microscopy, were treated with artemether-lumefantrine. RDTs and microscopy were then repeated at fixed intervals to estimate each test’s time to negativity after treatment and patient recovery. Results In the two settings, sensitivities ranged from 98.4 to 99.2 % for the HRP2 tests and 94.7 to 96.1 % for the pLDH test. Specificities were 98.9 and 98.8 % for the HRP2 tests and 99.7 % for the pLDH test in the low-transmission setting and 79.7, 80.7 and 93.9 %, respectively, in the high-transmission setting. Median time to become negative was 35–42 or more days for the HRP2 tests and 2 days for the pLDH test. Conclusions High transmission contexts and a long time to become negative resulted in considerably reduced specificities for the HRP2 tests. Choice of RDT for low- versus high-transmission settings should balance risks and benefits of over-treatment versus missing malaria cases. Trial registration: Registry number at ClinicalTrial.gov: NCT01325974
    Keywords Malaria ; Fever ; Diagnostic ; Rapid diagnostic test ; Sensitivity ; Specificity ; Arctic medicine. Tropical medicine ; RC955-962 ; Infectious and parasitic diseases ; RC109-216
    Subject code 150
    Language English
    Publishing date 2016-10-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  3. Article: Different origin and dispersal of sulfadoxine-resistant Plasmodium falciparum haplotypes between Eastern Africa and Democratic Republic of Congo

    Baraka, Vito / Carolyn Nabasumba / Christopher Delgado-Ratto / Deus S. Ishengoma / Hypolite Muhindo Mavoko / Jean-Pierre Van Geertruyden / Michael Alifrangis / Pascal Lutumba / Rashid A. Madebe / Sidsel Nag

    International journal of antimicrobial agents. 2017 Apr., v. 49, no. 4

    2017  

    Abstract: Sulfadoxine/pyrimethamine (SP) is still used for malaria control in sub-Saharan Africa; however, widespread resistance is a major concern. This study aimed to determine the dispersal and origin of sulfadoxine resistance lineages in the Democratic ... ...

    Abstract Sulfadoxine/pyrimethamine (SP) is still used for malaria control in sub-Saharan Africa; however, widespread resistance is a major concern. This study aimed to determine the dispersal and origin of sulfadoxine resistance lineages in the Democratic Republic of the Congo compared with East African Plasmodium falciparum dihydropteroate synthetase (Pfdhps) haplotypes. The analysis involved 264 isolates collected from patients with uncomplicated malaria from Tanzania, Uganda and DR Congo. Isolates were genotyped for Pfdhps mutations at codons 436, 437, 540, 581 and 613. Three microsatellite loci (0.8, 4.3 and 7.7 kb) flanking the Pfdhps gene were assayed. Evolutionary analysis revealed a shared origin of Pfdhps haplotypes in East Africa, with a distinct population clustering in DR Congo. Furthermore, in Tanzania there was an independent distinct origin of Pfdhps SGEGA resistant haplotype. In Uganda and Tanzania, gene flow patterns contribute to the dispersal and shared origin of parasites carrying double- and triple-mutant Pfdhps haplotypes associated with poor outcomes of intermittent preventive treatment during pregnancy using SP (IPTp-SP). However, the origins of the Pfdhps haplotypes in DR Congo and Eastern Africa sites are different. The genetic structure demonstrated a divergent and distinct population cluster predominated by single-mutant Pfdhps haplotypes at the DR Congo site. This reflects the limited dispersal of double- and triple-mutant Pfdhps haplotypes in DR Congo. This study highlights the current genetic structure and dispersal of high-grade Pfdhps resistant haplotypes, which is important to guide implementation of SP in malaria chemoprevention strategies in the region.
    Keywords chemoprevention ; codons ; drug resistance ; gene flow ; genes ; genotyping ; haplotypes ; malaria ; microsatellite repeats ; mutation ; parasites ; patients ; Plasmodium falciparum ; pregnancy ; pyrimethamine ; sulfadoxine ; Democratic Republic of the Congo ; Tanzania ; Uganda
    Language English
    Dates of publication 2017-04
    Size p. 456-464.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 1093977-5
    ISSN 1872-7913 ; 0924-8579
    ISSN (online) 1872-7913
    ISSN 0924-8579
    DOI 10.1016/j.ijantimicag.2016.12.007
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  4. Article ; Online: Paediatric pharmacovigilance

    Dan K Kajungu / Annette Erhart / Ambrose Otau Talisuna / Quique Bassat / Corine Karema / Carolyn Nabasumba / Michael Nambozi / Halidou Tinto / Peter Kremsner / Martin Meremikwu / Umberto D'Alessandro / Niko Speybroeck

    PLoS ONE, Vol 9, Iss 5, p e

    use of pharmacovigilance data mining algorithms for signal detection in a safety dataset of a paediatric clinical study conducted in seven African countries.

    2014  Volume 96388

    Abstract: Pharmacovigilance programmes monitor and help ensuring the safe use of medicines which is critical to the success of public health programmes. The commonest method used for discovering previously unknown safety risks is spontaneous notifications. In this ...

    Abstract Pharmacovigilance programmes monitor and help ensuring the safe use of medicines which is critical to the success of public health programmes. The commonest method used for discovering previously unknown safety risks is spontaneous notifications. In this study we examine the use of data mining algorithms to identify signals from adverse events reported in a phase IIIb/IV clinical trial evaluating the efficacy and safety of several Artemisinin-based combination therapies (ACTs) for treatment of uncomplicated malaria in African children.We used paediatric safety data from a multi-site, multi-country clinical study conducted in seven African countries (Burkina Faso, Gabon, Nigeria, Rwanda, Uganda, Zambia, and Mozambique). Each site compared three out of four ACTs, namely amodiaquine-artesunate (ASAQ), dihydroartemisinin-piperaquine (DHAPQ), artemether-lumefantrine (AL) or chlorproguanil/dapsone and artesunate (CD+A). We examine two pharmacovigilance signal detection methods, namely proportional reporting ratio and Bayesian Confidence Propagation Neural Network on the clinical safety dataset.Among the 4,116 children (6-59 months old) enrolled and followed up for 28 days post treatment, a total of 6,238 adverse events were reported resulting into 346 drug-event combinations. Nine signals were generated both by proportional reporting ratio and Bayesian Confidence Propagation Neural Network. A review of the manufacturer package leaflets, an online Multi-Drug Symptom/Interaction Checker (DoubleCheckMD) and further by therapeutic area experts reduced the number of signals to five. The ranking of some drug-adverse reaction pairs on the basis of their signal index differed between the two methods.Our two data mining methods were equally able to generate suspected signals using the pooled safety data from a phase IIIb/IV clinical trial. This analysis demonstrated the possibility of utilising clinical studies safety data for key pharmacovigilance activities like signal detection and evaluation. This approach can be applied ...
    Keywords Medicine ; R ; Science ; Q
    Subject code 310 ; 006
    Language English
    Publishing date 2014-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  5. Article ; Online: Efficacy and safety of re-treatment with the same artemisinin-based combination treatment (ACT) compared with an alternative ACT and quinine plus clindamycin after failure of first-line recommended ACT (QUINACT)

    Hypolite Muhindo Mavoko, DrPhD / Carolyn Nabasumba, MD / Raquel Inocêncio da Luz, PhD / Halidou Tinto, PhD / Umberto D'Alessandro, ProfPhD / Andrew Kambugu, MD / Vito Baraka, MSc / Anna Rosanas-Urgell, PhD / Pascal Lutumba, ProfPhD / Jean-Pierre Van geertruyden, PhD

    The Lancet Global Health, Vol 5, Iss 1, Pp e60-e

    a bicentre, open-label, phase 3, randomised controlled trial

    2017  Volume 68

    Abstract: Summary: Background: Quinine or alternative artemisinin-based combination treatment (ACT) is the recommended rescue treatment for uncomplicated malaria. However, patients are often re-treated with the same ACT though it is unclear whether this is the ... ...

    Abstract Summary: Background: Quinine or alternative artemisinin-based combination treatment (ACT) is the recommended rescue treatment for uncomplicated malaria. However, patients are often re-treated with the same ACT though it is unclear whether this is the most suitable approach. We assessed the efficacy and safety of re-treating malaria patients with uncomplicated failures with the same ACT used for the primary episode, compared with other rescue treatments. Methods: This was a bicentre, open-label, randomised, three-arm phase 3 trial done in Lisungi health centre in DR Congo, and Kazo health centre in Uganda in 2012–14. Children aged 12–60 months with recurrent malaria infection after treatment with the first-line ACT were randomly assigned to either re-treatment with the same first-line ACT, an alternative ACT, which were given for 3 days, or quinine-clindamycin (QnC), which was given for 5–7 days, following a 2:2:1 ratio. Randomisation was done by computer-generated randomisation list in a block design by country. The three treatment groups were assumed to have equivalent efficacy above 90%. Both the research team and parents or guardians were aware of treatment allocation. The primary outcome was the proportion of patients with an adequate clinical and parasitological response (ACPR) at day 28, in the per-protocol population. This trial was registered under the numbers NCT01374581 in ClinicalTrials.gov and PACTR201203000351114 in the Pan African Clinical Trials Registry. Findings: From May 22, 2012, to Jan 31, 2014, 571 children were included in the trial. 240 children were randomly assigned to the re-treatment ACT group, 233 to the alternative ACT group, and 98 to the QnC group. 500 children were assessed for the primary outcome. 71 others were not included because they did not complete the follow-up or PCR genotyping result was not conclusive. The ACPR response was similar in the three groups: 91·4% (95% CI 87·5–95·2) for the re-treatment ACT, 91·3% (95% CI 87·4–95·1) for the alternative ACT, and 89·5% (95% CI ...
    Keywords Public aspects of medicine ; RA1-1270
    Subject code 630
    Language English
    Publishing date 2017-01-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  6. Article ; Online: Dihydroartemisinin-piperaquine and artemether-lumefantrine for treating uncomplicated malaria in African children

    Quique Bassat / Modest Mulenga / Halidou Tinto / Patrice Piola / Steffen Borrmann / Clara Menéndez / Michael Nambozi / Innocent Valéa / Carolyn Nabasumba / Philip Sasi / Antonella Bacchieri / Marco Corsi / David Ubben / Ambrose Talisuna / Umberto D'Alessandro

    PLoS ONE, Vol 4, Iss 11, p e

    a randomised, non-inferiority trial.

    2009  Volume 7871

    Abstract: BACKGROUND:Artemisinin combination therapies (ACTs) are currently the preferred option for treating uncomplicated malaria. Dihydroartemisinin-piperaquine (DHA-PQP) is a promising fixed-dose ACT with limited information on its safety and efficacy in ... ...

    Abstract BACKGROUND:Artemisinin combination therapies (ACTs) are currently the preferred option for treating uncomplicated malaria. Dihydroartemisinin-piperaquine (DHA-PQP) is a promising fixed-dose ACT with limited information on its safety and efficacy in African children. METHODOLOGY/PRINCIPAL FINDINGS:The non-inferiority of DHA-PQP versus artemether-lumefantrine (AL) in children 6-59 months old with uncomplicated P. falciparum malaria was tested in five African countries (Burkina Faso, Kenya, Mozambique, Uganda and Zambia). Patients were randomised (2:1) to receive either DHA-PQP or AL. Non-inferiority was assessed using a margin of -5% for the lower limit of the one-sided 97.5% confidence interval on the treatment difference (DHA-PQP vs. AL) of the day 28 polymerase chain reaction (PCR) corrected cure rate. Efficacy analysis was performed in several populations, and two of them are presented here: intention-to-treat (ITT) and enlarged per-protocol (ePP). 1553 children were randomised, 1039 receiving DHA-PQP and 514 AL. The PCR-corrected day 28 cure rate was 90.4% (ITT) and 94.7% (ePP) in the DHA-PQP group, and 90.0% (ITT) and 95.3% (ePP) in the AL group. The lower limits of the one-sided 97.5% CI of the difference between the two treatments were -2.80% and -2.96%, in the ITT and ePP populations, respectively. In the ITT population, the Kaplan-Meier estimate of the proportion of new infections up to Day 42 was 13.55% (95% CI: 11.35%-15.76%) for DHA-PQP vs 24.00% (95% CI: 20.11%-27.88%) for AL (p<0.0001). CONCLUSIONS/SIGNIFICANCE:DHA-PQP is as efficacious as AL in treating uncomplicated malaria in African children from different endemicity settings, and shows a comparable safety profile. The occurrence of new infections within the 42-day follow up was significantly lower in the DHA-PQP group, indicating a longer post-treatment prophylactic effect. TRIAL REGISTRATION:Controlled-trials.com ISRCTN16263443.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2009-11-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  7. Article ; Online: Immunogenicity of fractional doses of tetravalent a/c/y/w135 meningococcal polysaccharide vaccine

    Philippe J Guerin / Lisbeth M Naess / Carole Fogg / Einar Rosenqvist / Loretxu Pinoges / Francis Bajunirwe / Carolyn Nabasumba / Ray Borrow / Leif O Frøholm / Salah Ghabri / Vincent Batwala / Rogers Twesigye / Ingeborg S Aaberge / John-Arne Røttingen / Patrice Piola / Dominique A Caugant

    PLoS Neglected Tropical Diseases, Vol 2, Iss 12, p e

    results from a randomized non-inferiority controlled trial in Uganda.

    2008  Volume 342

    Abstract: Neisseria meningitidis serogroup A is the main causative pathogen of meningitis epidemics in sub-Saharan Africa. In recent years, serogroup W135 has also been the cause of epidemics. Mass vaccination campaigns with polysaccharide vaccines are key ... ...

    Abstract Neisseria meningitidis serogroup A is the main causative pathogen of meningitis epidemics in sub-Saharan Africa. In recent years, serogroup W135 has also been the cause of epidemics. Mass vaccination campaigns with polysaccharide vaccines are key elements in controlling these epidemics. Facing global vaccine shortage, we explored the use of fractional doses of a licensed A/C/Y/W135 polysaccharide meningococcal vaccine.We conducted a randomized, non-inferiority trial in 750 healthy volunteers 2-19 years old in Mbarara, Uganda, to compare the immune response of the full dose of the vaccine versus fractional doses (1/5 or 1/10). Safety and tolerability data were collected for all subjects during the 4 weeks following the injection. Pre- and post-vaccination sera were analyzed by measuring serum bactericidal activity (SBA) with baby rabbit complement. A responder was defined as a subject with a > or =4-fold increase in SBA against a target strain from each serogroup and SBA titer > or =128. For serogroup W135, 94% and 97% of the vaccinees in the 1/5- and 1/10-dose arms, respectively, were responders, versus 94% in the full-dose arm; for serogroup A, 92% and 88% were responders, respectively, versus 95%. Non-inferiority was demonstrated between the full dose and both fractional doses in SBA seroresponse against serogroups W135 and Y, in total population analysis. Non-inferiority was shown between the full and 1/5 doses for serogroup A in the population non-immune prior to vaccination. Non-inferiority was not shown for any of the fractionate doses for serogroup C. Safety and tolerability data were favourable, as observed in other studies.While the advent of conjugate A vaccine is anticipated to largely contribute to control serogroup A outbreaks in Africa, the scale-up of its production will not cover the entire "Meningitis Belt" target population for at least the next 3 to 5 years. In view of the current shortage of meningococcal vaccines for Africa, the use of 1/5 fractional doses should be considered as an alternative in mass vaccination campaigns.ClinicalTrials.gov NCT00271479.
    Keywords Arctic medicine. Tropical medicine ; RC955-962 ; Public aspects of medicine ; RA1-1270
    Subject code 630
    Language English
    Publishing date 2008-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

To top