Displaying all 12 publications

Abstract:
Sort:
  1. Naing C, Aung K, Win DK, Wah MJ
    Trans R Soc Trop Med Hyg, 2010 Nov;104(11):695-705.
    PMID: 20850161 DOI: 10.1016/j.trstmh.2010.08.009
    Chloroquine (CQ) is a relatively inexpensive drug for treatment of malaria. If efficacy of CQ is still assumed, then it should be indicated in malaria treatment policies as the drug of choice for uncomplicated Plasmodium vivax malaria in endemic countries with resource constraints. The objective of this review is to summarize the existing evidence on the relative efficacy and safety of CQ in treating patients with uncomplicated P. vivax malaria in endemic countries. We searched online data bases (PUBMED, MEDLINE, EMBASE, The Cochrane Library) and the reference lists of the retrieved articles. Fifteen randomized controlled trials (n=6215) assessing the relative efficacy and safety of CQ for treatment of uncomplicated P. vivax malaria were included. CQ monotherapy was compared to CQ plus primaquine (PQ), artemisinin/artemether, artemisinin based combination therapy, quinine, CQ plus tafenoquine, chlorguanil plus dapsone, azithromycin, or placebo. Treatment efficacy was not significantly different between the CQ monotherapy group and that of the CQ with PQ 14 day group at 28 day follow-up (55/711, 7.7% vs 35/712, 4.9%; P=0.16). Evidence from the trials identified for this review draw a fairly clear conclusion about the relative efficacy and safety of CQ for treating uncomplicated P. vivax malaria infection. However, further research in this field with well powered, randomized, non-inferiority design, using the standardized protocol is needed.
    Matched MeSH terms: Plasmodium vivax/drug effects*
  2. Supramaniam V, Datta GC, Singam V, Singh J
    Med J Malaysia, 1987 Mar;42(1):44-9.
    PMID: 3323860
    Malaria is the most important communicable disease in the field for the Malaysian soldier. His chief weapon is chemoprophylaxis. This was proguanil hydrochloride in the '50s, changed to Daraclor in 1962; since late 1985, Fansidar only is used. The incidence of malaria over the years has fluctuated widely and had its peak in 1977 at 29.7/1,000 soldiers and since then has shown a downward trend. Studies carried out to study the problem are noted briefly. Antimalarial discipline in the field, continued surveillance and integrated control measures in the base are emphasised in the fight against malaria.
    Matched MeSH terms: Plasmodium vivax/drug effects
  3. Dondero TJ, Parsons RE, Ponnampalam JT
    Trans R Soc Trop Med Hyg, 1976;70(2):145-8.
    PMID: 785725
    In vivo chloroquine resistance surveys, which allowed for detection of late recrudescing RI resistance, were conducted in three regions of Peninsular Malaysia, which were previously not recognized as having appreciable drug resistance. Among the 485 Plasmodium falciparum infections tested resistance rates ranged locally from 20% to 67% in those with parasitaemias over 1,000 per mm3, and 5% to 59% in all parasitaemias. The region found to have the most serious resistance was western Pahang. In one study a combination of chloroquine and pyrimethamine proved no more efficacious than chloroquine alone. Most of the resistance encountered was the late recrudescing RI type. There was no apparent correlation between drug resistance and Anopheles balabacensis as this species was not found despite intensive collections in two of the three main regions. There was no evidence of resistance among the 222 P. vivax and 35 P. malariae infections also tested.
    Matched MeSH terms: Plasmodium vivax/drug effects
  4. Zhang R, Suwanarusk R, Malleret B, Cooke BM, Nosten F, Lau YL, et al.
    J Infect Dis, 2016 Jan 1;213(1):100-4.
    PMID: 26136472 DOI: 10.1093/infdis/jiv358
    Recent clinical trials revealed a surprisingly rapid clearance of red blood cells (RBCs) infected with malaria parasites by the spiroindolone KAE609. Here, we show that ring-stage parasite-infected RBCs exposed to KAE609 become spherical and rigid, probably through osmotic dysregulation consequent to the disruption of the parasite's sodium efflux pump (adenosine triphosphate 4). We also show that this peculiar drug effect is likely to cause accelerated splenic clearance of the rheologically impaired Plasmodium vivax- and Plasmodium falciparum-infected RBCs.
    Matched MeSH terms: Plasmodium vivax/drug effects*
  5. Thriemer K, Bobogare A, Ley B, Gudo CS, Alam MS, Anstey NM, et al.
    Malar J, 2018 Jun 20;17(1):241.
    PMID: 29925430 DOI: 10.1186/s12936-018-2380-8
    The goal to eliminate malaria from the Asia-Pacific by 2030 will require the safe and widespread delivery of effective radical cure of malaria. In October 2017, the Asia Pacific Malaria Elimination Network Vivax Working Group met to discuss the impediments to primaquine (PQ) radical cure, how these can be overcome and the methodological difficulties in assessing clinical effectiveness of radical cure. The salient discussions of this meeting which involved 110 representatives from 18 partner countries and 21 institutional partner organizations are reported. Context specific strategies to improve adherence are needed to increase understanding and awareness of PQ within affected communities; these must include education and health promotion programs. Lessons learned from other disease programs highlight that a package of approaches has the greatest potential to change patient and prescriber habits, however optimizing the components of this approach and quantifying their effectiveness is challenging. In a trial setting, the reactivity of participants results in patients altering their behaviour and creates inherent bias. Although bias can be reduced by integrating data collection into the routine health care and surveillance systems, this comes at a cost of decreasing the detection of clinical outcomes. Measuring adherence and the factors that relate to it, also requires an in-depth understanding of the context and the underlying sociocultural logic that supports it. Reaching the elimination goal will require innovative approaches to improve radical cure for vivax malaria, as well as the methods to evaluate its effectiveness.
    Matched MeSH terms: Plasmodium vivax/drug effects*
  6. Fatih FA, Staines HM, Siner A, Ahmed MA, Woon LC, Pasini EM, et al.
    Malar J, 2013;12:425.
    PMID: 24245918 DOI: 10.1186/1475-2875-12-425
    Evidence suggests that Plasmodium knowlesi malaria in Sarawak, Malaysian Borneo remains zoonotic, meaning anti-malarial drug resistance is unlikely to have developed in the absence of drug selection pressure. Therefore, adequate response to available anti-malarial treatments is assumed.
    Matched MeSH terms: Plasmodium vivax/drug effects
  7. Noisang C, Prosser C, Meyer W, Chemoh W, Ellis J, Sawangjaroen N, et al.
    Malar J, 2019 Aug 15;18(1):275.
    PMID: 31416468 DOI: 10.1186/s12936-019-2903-y
    BACKGROUND: Drug resistance within the major malaria parasites Plasmodium vivax and Plasmodium falciparum threatens malaria control and elimination in Southeast Asia. Plasmodium vivax first-line treatment drug is chloroquine together with primaquine, and the first-line treatment for P. falciparum malaria is artemisinin in combination with a partner drug. Plasmodium vivax and P. falciparum parasites resistant to their respective first-line therapies are now found within Southeast Asia. The resistance perimeters may include high transmission regions of Southern Thailand which are underrepresented in surveillance efforts.

    METHODS: This study investigated blood samples from malaria centres in Southern Thailand. Genetic loci associated with drug resistance were amplified and sequenced. Drug resistance associated genes Pvmdr1, Pvcrt-o, Pvdhfr, and Pvdhps were characterized for 145 cases of P. vivax malaria, as well as the artemisinin resistance-associated Pfkelch13 gene from 91 cases of P. falciparum malaria.

    RESULTS: Plasmodium vivax samples from Southern Thai provinces showed numerous chloroquine and antifolate resistance-associated mutations, including SNP and Pvcrt-o K10-insertion combinations suggestive of chloroquine resistant P. vivax phenotypes. A high proportion of the C580Y coding mutation (conferring artemisinin resistance) was detected in P. falciparum samples originating from Ranong and Yala (where the mutation was previously unreported).

    CONCLUSIONS: The results demonstrate a risk of chloroquine and antifolate resistant P. vivax phenotypes in Southern Thailand, and artemisinin resistant P. falciparum observed as far south as the Thai-Malaysian border region. Ongoing surveillance of antimalarial drug resistance markers is called for in Southern Thailand to inform case management.

    Matched MeSH terms: Plasmodium vivax/drug effects*
  8. Malik M, Hassali MA, Shafie AA, Hussain A
    East Mediterr Health J, 2014 Apr;20(4):221-8.
    PMID: 24952118
    Despite the availability of standard treatment guidelines for malaria in Pakistan adherence to protocols by prescribers is poor. This descriptive, cross-sectional study aimed to explore the perceptions and knowledge of prescribers in Islamabad and Rawalpindi cities towards adherence to standard treatment guidelines for malaria. A questionnaire was distributed to a random sample of 360 prescribers; 64.7% were satisfied with the available antimalarial drugs and 41.3% agreed that antimalarial drugs should only be prescribed after diagnostic testing. Only half the prescribers had the guidelines available in their health facility. Almost all the prescribers (97.7%) agreed that there was a need for more educational programmes about the guidelines. Most prescribers were unaware of the correct standard treatment regimen for Plasmodium falciparum and P. vivax malaria. There were no differences in knowledge between males and females, but prescribers having more experience, practising as general practitioners and working in private health-care facilities possessed significantly better knowledge than their counterparts.
    Matched MeSH terms: Plasmodium vivax/drug effects
  9. Shah SM, Ullah F, Khan S, Shah SM, de Matas M, Hussain Z, et al.
    Drug Des Devel Ther, 2016;10:3837-3850.
    PMID: 27920499
    Artemether (ARTM) is a very effective antimalarial drug with poor solubility and consequently low bioavailability. Smart nanocrystals of ARTM with particle size of 161±1.5 nm and polydispersity index of 0.172±0.01 were produced in <1 hour using a wet milling technology, Dena(®) DM-100. The crystallinity of the processed ARTM was confirmed using differential scanning calorimetry and powder X-ray diffraction. The saturation solubility of the ARTM nanocrystals was substantially increased to 900 µg/mL compared to the raw ARTM in water (145.0±2.3 µg/mL) and stabilizer solution (300.0±2.0 µg/mL). The physical stability studies conducted for 90 days demonstrated that nanocrystals stored at 2°C-8°C and 25°C were very stable compared to the samples stored at 40°C. The nanocrystals were also shown to be stable when processed at acidic pH (2.0). The solubility and dissolution rate of ARTM nanocrystals were significantly increased (P<0.05) compared to those of its bulk powder form. The results of in vitro studies showed significant antimalarial effect (P<0.05) against Plasmodium falciparum and Plasmodium vivax. The IC50 (median lethal oral dose) value of ARTM nanocrystals was 28- and 54-fold lower than the IC50 value of unprocessed drug and 13- and 21-fold lower than the IC50 value of the marketed tablets, respectively. In addition, ARTM nanocrystals at the same dose (2 mg/kg) showed significantly (P<0.05) higher reduction in percent parasitemia (89%) against P. vivax compared to the unprocessed (27%), marketed tablets (45%), and microsuspension (60%). The acute toxicity study demonstrated that the LD50 value of ARTM nanocrystals is between 1,500 mg/kg and 2,000 mg/kg when given orally. This study demonstrated that the wet milling technology (Dena(®) DM-100) can produce smart nanocrystals of ARTM with enhanced antimalarial activities.
    Matched MeSH terms: Plasmodium vivax/drug effects
  10. Commons RJ, Simpson JA, Thriemer K, Chu CS, Douglas NM, Abreha T, et al.
    BMC Med, 2019 08 01;17(1):151.
    PMID: 31366382 DOI: 10.1186/s12916-019-1386-6
    BACKGROUND: Malaria causes a reduction in haemoglobin that is compounded by primaquine, particularly in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. The aim of this study was to determine the relative contributions to red cell loss of malaria and primaquine in patients with uncomplicated Plasmodium vivax.

    METHODS: A systematic review identified P. vivax efficacy studies of chloroquine with or without primaquine published between January 2000 and March 2017. Individual patient data were pooled using standardised methodology, and the haematological response versus time was quantified using a multivariable linear mixed effects model with non-linear terms for time. Mean differences in haemoglobin between treatment groups at day of nadir and day 42 were estimated from this model.

    RESULTS: In total, 3421 patients from 29 studies were included: 1692 (49.5%) with normal G6PD status, 1701 (49.7%) with unknown status and 28 (0.8%) deficient or borderline individuals. Of 1975 patients treated with chloroquine alone, the mean haemoglobin fell from 12.22 g/dL [95% CI 11.93, 12.50] on day 0 to a nadir of 11.64 g/dL [11.36, 11.93] on day 2, before rising to 12.88 g/dL [12.60, 13.17] on day 42. In comparison to chloroquine alone, the mean haemoglobin in 1446 patients treated with chloroquine plus primaquine was - 0.13 g/dL [- 0.27, 0.01] lower at day of nadir (p = 0.072), but 0.49 g/dL [0.28, 0.69] higher by day 42 (p  25% to  5 g/dL.

    CONCLUSIONS: Primaquine has the potential to reduce malaria-related anaemia at day 42 and beyond by preventing recurrent parasitaemia. Its widespread implementation will require accurate diagnosis of G6PD deficiency to reduce the risk of drug-induced haemolysis in vulnerable individuals.

    TRIAL REGISTRATION: This trial was registered with PROSPERO: CRD42016053312. The date of the first registration was 23 December 2016.

    Matched MeSH terms: Plasmodium vivax/drug effects
  11. Commons RJ, Simpson JA, Thriemer K, Humphreys GS, Abreha T, Alemu SG, et al.
    Lancet Infect Dis, 2018 Sep;18(9):1025-1034.
    PMID: 30033231 DOI: 10.1016/S1473-3099(18)30348-7
    BACKGROUND: Chloroquine remains the mainstay of treatment for Plasmodium vivax malaria despite increasing reports of treatment failure. We did a systematic review and meta-analysis to investigate the effect of chloroquine dose and the addition of primaquine on the risk of recurrent vivax malaria across different settings.

    METHODS: A systematic review done in MEDLINE, Web of Science, Embase, and Cochrane Database of Systematic Reviews identified P vivax clinical trials published between Jan 1, 2000, and March 22, 2017. Principal investigators were invited to share individual patient data, which were pooled using standardised methods. Cox regression analyses with random effects for study site were used to investigate the roles of chloroquine dose and primaquine use on rate of recurrence between day 7 and day 42 (primary outcome). The review protocol is registered in PROSPERO, number CRD42016053310.

    FINDINGS: Of 134 identified chloroquine studies, 37 studies (from 17 countries) and 5240 patients were included. 2990 patients were treated with chloroquine alone, of whom 1041 (34·8%) received a dose below the target 25 mg/kg. The risk of recurrence was 32·4% (95% CI 29·8-35·1) by day 42. After controlling for confounders, a 5 mg/kg higher chloroquine dose reduced the rate of recurrence overall (adjusted hazard ratio [AHR] 0·82, 95% CI 0·69-0·97; p=0·021) and in children younger than 5 years (0·59, 0·41-0·86; p=0·0058). Adding primaquine reduced the risk of recurrence to 4·9% (95% CI 3·1-7·7) by day 42, which is lower than with chloroquine alone (AHR 0·10, 0·05-0·17; p<0·0001).

    INTERPRETATION: Chloroquine is commonly under-dosed in the treatment of vivax malaria. Increasing the recommended dose to 30 mg/kg in children younger than 5 years could reduce substantially the risk of early recurrence when primaquine is not given. Radical cure with primaquine was highly effective in preventing early recurrence and may also improve blood schizontocidal efficacy against chloroquine-resistant P vivax.

    FUNDING: Wellcome Trust, Australian National Health and Medical Research Council, and Bill & Melinda Gates Foundation.

    Matched MeSH terms: Plasmodium vivax/drug effects*
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links