scholarly journals Influence of Cytochrome P450 (CYP) 2C8 Polymorphisms on the Efficacy and Tolerability of Artesunate-Amodiaquine Treatment of Uncomplicated Plasmodium Falciparum Malaria in Zanzibar

Author(s):  
Leyre Pernaute-Lau ◽  
Ulrika Morris ◽  
Mwinyi Msellem ◽  
Andreas Mårtensson ◽  
Anders Björkman ◽  
...  

Abstract Background The antimalarial drug amodiaquine, a commonly used long acting partner drug in artemisinin-based combination therapy, is metabolized to active desethyl-amodiaquine (DEAQ) by cytochrome P450 2C8 (CYP2C8). The CYP2C8 gene carries several polymorphisms including the more frequent minor alleles CYP2C8*2 and CYP2C8*3. These minor alleles have been associated with decreased enzymatic activity, slowing the amodiaquine biotransformation towards DEAQ. This study aimed to assess the influence of CYP2C8 polymorphisms on the efficacy and tolerability of artesunate-amodiaquine treatment for uncomplicated Plasmodium falciparum malaria in Zanzibar.Methods We analysed data from 618 children <5 years with uncomplicated P. falciparum malaria enrolled in two randomized clinical trials comparing artesunate-amodiaquine and artemether-lumefantrine in 2002-2005 in Zanzibar. CYP2C8*2 and CYP2C8*3 genotypes were determined by PCR-restriction fragment length polymorphism and assessed in relation to clinical data on treatment outcome and tolerance. Results The allele frequencies of CYP2C8*2 and CYP2C8*3 were 17.5% (95% CI 15.4-19.7%) and 2.7% (95% CI 1.8-3.7%), respectively. There was no significant difference in the proportion of subjects carrying either CYP2C8*2 or CYP2C8*3 alleles amongst those with reinfections (44.1 %; 95% CI 33.8-54.8) or those with recrudescent infections (48.3%; 95% CI 29.4-67.5), compared to those with adequate clinical and parasitological response (36.7 %; 95% CI 30.0-43.9) (P = 0.25 and P = 0.31, respectively). However, patients carrying either the CYP2C8*2 or CYP2C8*3 allele were significantly associated with increased occurrence of non-serious adverse events compare with CYP2C8 *1/*1 wildtype homozygotes (44.9%; 95% CI 36.1-54.0 versus 28.1%; 95% CI 21.9-35.0, respectively; P = 0.003). Conclusions CYP2C8 genotypes did not influence treatment efficacy directly, but the tolerability to ASAQ may be reduced in subjects carrying the CYP2C8*3 and CYP2C8*2 alleles. The importance of this non-negligible association with regards to amodiaquine-based malaria chemotherapy warrants further investigation.

2021 ◽  
Author(s):  
Leyre Pernaute-Lau ◽  
Ulrika Morris ◽  
Mwinyi Msellem ◽  
Andreas Mårtensson ◽  
Anders Björkman ◽  
...  

Abstract BackgroundThe antimalarial drug amodiaquine, a commonly used long acting partner drug in artemisinin-based combination therapy, is metabolized to active desethyl-amodiaquine (DEAQ) by cytochrome P450 2C8 (CYP2C8). The CYP2C8 gene carries several polymorphisms including the more frequent minor alleles CYP2C8*2 and CYP2C8*3. These minor alleles have been associated with decreased enzymatic activity, slowing the amodiaquine biotransformation towards DEAQ. This study aimed to assess the influence of these CYP2C8 polymorphisms on the efficacy and tolerability of artesunate-amodiaquine treatment for uncomplicated Plasmodium falciparum malaria in Zanzibar.MethodsWe analysed data from 618 children under 5 years of age with uncomplicated P. falciparum malaria enrolled in two randomized clinical trials comparing artesunate-amodiaquine and artemether-lumefantrine in 2002-2005 in Zanzibar. CYP2C8*2 and CYP2C8*3 genotype frequencies were determined by PCR-restriction fragment length polymorphism. Statistical associations between CYP2C8*2 and/or CYP2C8*3 allele carriers and treatment outcome or occurrence of adverse events were assessed by Fisher’s Exact test.ResultsThe allele frequencies of CYP2C8*2 and CYP2C8*3 were 17.5% (95% CI 15.4-19.7%) and 2.7% (95% CI 1.8-3.7%), respectively. There was no significant difference in the proportion of subjects carrying either CYP2C8*2 or CYP2C8*3 alleles amongst those with reinfections (44.1%; 95% CI 33.8-54.8) or those with recrudescent infections (48.3%; 95% CI 29.4-67.5), compared to those with an adequate clinical and parasitological response (36.7%; 95% CI 30.0-43.9) (P = 0.25 and P = 0.31, respectively). However, patients carrying either the CYP2C8*2 or CYP2C8*3 alleles were significantly associated with an increased occurrence of non-serious adverse events, when compared with CYP2C8 *1/*1 wildtype homozygotes (44.9%; 95% CI 36.1-54.0 versus 28.1%; 95% CI 21.9-35.0, respectively; P = 0.003). ConclusionsCYP2C8 genotypes did not influence treatment efficacy directly, but the tolerability to AS-AQ may be reduced in subjects carrying the CYP2C8*2 and CYP2C8*3 alleles. The importance of this non-negligible association with regards to amodiaquine-based malaria chemotherapy warrants further investigation.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Leyre Pernaute-Lau ◽  
Ulrika Morris ◽  
Mwinyi Msellem ◽  
Andreas Mårtensson ◽  
Anders Björkman ◽  
...  

Abstract Background The anti-malarial drug, amodiaquine, a commonly used, long-acting partner drug in artemisinin-based combination therapy, is metabolized to active desethyl-amodiaquine (DEAQ) by cytochrome P450 2C8 (CYP2C8). The CYP2C8 gene carries several polymorphisms including the more frequent minor alleles, CYP2C8*2 and CYP2C8*3. These minor alleles have been associated with decreased enzymatic activity, slowing the amodiaquine biotransformation towards DEAQ. This study aimed to assess the influence of these CYP2C8 polymorphisms on the efficacy and tolerability of artesunate–amodiaquine (AS–AQ) treatment for uncomplicated Plasmodium falciparum malaria in Zanzibar. Methods Dried blood spots on filter paper were collected from 618 children enrolled in two randomized clinical trials comparing AS–AQ and artemether-lumefantrine in 2002–2005 in Zanzibar. Study participant were under five years of age with uncomplicated falciparum malaria. Human CYP2C8*2 and CYP2C8*3 genotype frequencies were determined by PCR-restriction fragment length polymorphism. Statistical associations between CYP2C8*2 and/or CYP2C8*3 allele carriers and treatment outcome or occurrence of adverse events were assessed by Fisher’s exact test. Results The allele frequencies of CYP2C8*2 and CYP2C8*3 were 17.5 % (95 % CI 15.4–19.7) and 2.7 % (95 % CI 1.8–3.7), respectively. There was no significant difference in the proportion of subjects carrying either CYP2C8*2 or CYP2C8*3 alleles amongst those with re-infections (44.1 %; 95 % CI 33.8–54.8) or those with recrudescent infections (48.3 %; 95 % CI 29.4–67.5), compared to those with an adequate clinical and parasitological response (36.7 %; 95 % CI 30.0-43.9) (P = 0.25 and P = 0.31, respectively). However, patients carrying either CYP2C8*2 or CYP2C8*3 alleles were significantly associated with an increased occurrence of non-serious adverse events, when compared with CYP2C8 *1/*1 wild type homozygotes (44.9 %; 95 % CI 36.1–54.0 vs. 28.1 %; 95 % CI 21.9–35.0, respectively; P = 0.003). Conclusions CYP2C8 genotypes did not influence treatment efficacy directly, but the tolerability to AS–AQ may be reduced in subjects carrying the CYP2C8*2 and CYP2C8*3 alleles. The importance of this non-negligible association with regard to amodiaquine-based malaria chemotherapy warrants further investigation.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S639-S640
Author(s):  
L W Preston Church

Abstract Background Sanaria’s PfSPZ Vaccine prevents Plasmodium falciparum (Pf) infection transmitted in the field and by controlled human malaria infection. Safety of PfSPZ Vaccine has been demonstrated in 12 randomized, double-blind, placebo-controlled trials (RCT) varying in regimen from 3 to 5 doses over 4 to 20 weeks and in size from 18 to 332 subjects in adults in the US and EU and 5-month to 65-year-olds in 5 countries in sub-Saharan Africa. This study was conducted to analyze solicited adverse event (AE) and laboratory data by random effects meta-analysis. Methods PfSPZ Vaccine is composed of radiation-attenuated, aseptic, purified, cryopreserved Pf sporozoites (SPZ) administered by direct venous inoculation (DVI). Normal saline (NS) is always the placebo. Data from all completed RCTs were included as either age &gt; 18 years (n=598) or age 5 months to 17 years (n=641). Any subject receiving at least one dose was included. A random-effects model was used to study vaccine safety and I2 to evaluate heterogeneity. Analysis was performed for any systemic solicited AE and for the most frequently observed AEs and laboratory abnormalities. Sensitivity analyses were performed by removal of trials with zero events to evaluate potential bias. Results When examined individually, only 1 trial had a significant difference between PfSPZ Vaccine and NS for any AE (myalgias in adults). In the adult meta-analysis, there was no difference in the random effects risk ratios (RR) for having any vaccine-related AEs (1.40, 95% confidence interval (CI) 0.88-2.28), or for fever (0.75, 0.24-2.35), headache (1.23, 0.74-2.02), fatigue (0.72, 0.19-2.54), or myalgia (1.09, 0.26-4.68). In the pediatric meta-analysis there was no difference between the RR for PfSPZ Vaccine and NS for any AE (0.84, 0.59-1.18) or for fever (1.09, 0.44-2.69). No significant differences in the most common grade 2 or higher laboratory abnormalities – declines in hemoglobin, neutrophil or platelet count – were detected. Sensitivity analysis did not change the results. Conclusion There was no difference in risk for AEs or lab abnormalities between PfSPZ Vaccine and NS, indicating that PfSPZ Vaccine administered by DVI was extremely safe and well tolerated in 5-month- to 65-year-olds. Disclosures LW Preston Church, MD, FIDSA, Sanaria Inc. (Employee)


Author(s):  
Madhvi Chahar ◽  
Anup Anvikar ◽  
Neena Valecha

Sulphadoxine and pyrimethamine (SP) have been used as long-acting partner antimalarial drugs in artemisinin combination therapy (ACT) for falciparum malaria. The emergence and increasing spread of SP resistance in malaria-endemic areas have become a challenge for the control of malaria. Therefore, regular monitoring of the mutation status of partner drugs is important for the better management of drug policy. There are limitations with traditional molecular methods and there is an urgent need for an easy method for diagnosis of drug resistance. In this study we have introduced and developed a novel single nucleotide polymorphism loop-mediated isothermal amplification (SNP–LAMP) approach based on a hydroxynaphthol blue (HNB) indicator for the easier and quicker detection of pyrimethamine resistance in Plasmodium falciparum malaria. To implement this novel approach, many sets of LAMP primers were designed and tested. Finally, one set of forward inner primer M1 (FIPM1) of LAMP primer was selected that specifically distinguishes pyrimethamine-resistant P. falciparum malaria. The LAMP reactions were optimized at 60–66 °C for 45 min. High sensitivity (7 parasites/µL) was observed with 10−4 fold dilutions (<2 ng DNA) of genomic DNA. Moreover, this approach has the potential to be applied even in laboratories unfamiliar with PCR or other molecular methods, and in future, this can be helpful for the better management of anti-malarial policy.


2017 ◽  
Vol 43 (4) ◽  
pp. 302-312 ◽  
Author(s):  
Israel Silva Maia ◽  
Mariângela Pimentel Pincelli ◽  
Victor Figueiredo Leite ◽  
João Amadera ◽  
Anna Maria Buehler

ABSTRACT Objective: To determine whether long-acting muscarinic antagonists (LAMAs) provide superior therapeutic effects over long-acting β2 agonists (LABAs) for preventing COPD exacerbations. Methods: This was a systematic review and meta-analysis of randomized clinical trials involving patients with stable, moderate to severe COPD according to the Global Initiative for Chronic Obstructive Lung Disease criteria, treated with a LAMA (i.e., tiotropium bromide, aclidinium, or glycopyrronium), followed for at least 12 weeks and compared with controls using a LABA in isolation or in combination with a corticosteroid. Results: A total of 2,622 studies were analyzed for possible inclusion on the basis of their title and abstract; 9 studies (17,120 participants) were included in the analysis. In comparison with LABAs, LAMAs led to a greater decrease in the exacerbation rate ratio (relative risk [RR] = 0.88; 95% CI: 0.84-0.93]; a lower proportion of patients who experienced at least one exacerbation (RR = 0.90; 95% CI: 0.87-0.94; p < 0.00001); a lower risk of exacerbation-related hospitalizations (RR = 0.78; 95% CI: 0.69-0.87; p < 0.0001); and a lower number of serious adverse events (RR = 0.81; 95% CI: 0.67-0.96; p = 0.0002). The overall quality of evidence was moderate for all outcomes. Conclusions: The major findings of this systematic review and meta-analysis were that LAMAs significantly reduced the exacerbation rate (exacerbation episodes/year), as well as the number of exacerbation episodes, of hospitalizations, and of serious adverse events.


2021 ◽  
Author(s):  
Chris Ebong ◽  
Asadu Sserwanga ◽  
Jane Frances Namuganga ◽  
James Kapisi ◽  
Arthur Mpimbaza ◽  
...  

Abstract Background In Uganda, artemether-lumefantrine (AL) is the first-line therapy and dihydroartemisinin-piperaquine (DP) the second-line therapy for the treatment of uncomplicated malaria. We evaluated the efficacy and safety of AL and DP in the management of uncomplicated Plasmodium falciparum malaria and measured the prevalence of molecular markers of resistance in three sentinel sites from 2018–2019 in Uganda. Methods This was a randomized, open-label, phase IV clinical trial. Children aged 6 months to 10 years with uncomplicated falciparum malaria were randomly assigned to treatment with AL or DP and followed for 28 and 42 days, respectively. Genotyping was used to distinguish recrudescence from new infection, and a Bayesian algorithm was used to assign each treatment failure a posterior probability of recrudescence. For monitoring resistance, Pfk13 and Pfmdr1 genes were Sanger sequenced and plasmepsin-2 copy number was assessed by qPCR. Results There were no early treatment failures. The uncorrected 28-day cumulative efficacy of AL ranged from 41.2–71.2% and the PCR-corrected cumulative 28-day efficacy of AL ranged from 87.2–94.4%. The uncorrected 28-day cumulative efficacy of DP ranged from 95.8–97.9% and the PCR-corrected cumulative 28-day efficacy of DP ranged from 98.9–100%. The uncorrected 42-day efficacy of DP ranged from 73.5–87.4% and the PCR-corrected 42-day efficacy of DP ranged from 92.1–97.5%. There were no reported serious adverse events associated with any of the regimens. No resistance-associated mutations in the Pfk13 gene were found in the successfully sequenced samples. In the AL arm, the NFD haplotype (N86Y, Y184F, D1246Y) was the predominant Pfmdr1 haplotype, present in 78 of 127 (61%) and 76 of 110 (69%) of the day 0 and day of failure samples, respectively. All the day 0 samples in the DP arm had one copy of the plasmepsin-2 gene. Conclusions DP remains highly effective and safe for the treatment of uncomplicated malaria in Uganda. Recurrent infections with AL were common. In Busia and Arua, the 95% confidence interval for PCR-corrected AL efficacy fell below 90%. Further efficacy monitoring for AL, including pharmacokinetic studies, is recommended. Trial registration: The trail was also registered with the ISRCTN registry with study Trial no PACTR201811640750761.


Author(s):  
Augustin Kpemasse ◽  
Fortune Dagnon ◽  
Ramani Saliou ◽  
Alexis Sacca Yarou Maye ◽  
Cyriaque Dossou Affoukou ◽  
...  

In 2005, artemether-lumefantrine (AL), an artemisinin-based combination therapy, was introduced as the first-line treatment of uncomplicated Plasmodium falciparum malaria in Benin. Per World Health Organization recommendations to monitor the efficacy of antimalarial treatment, we conducted a therapeutic efficacy study with AL for uncomplicated P. falciparum malaria in Bohicon and Kandi, Benin, from 2018 to 2019. Febrile patients aged 6 to 59 months with confirmed P. falciparum monoinfection received supervised doses of AL for 3 days. We monitored patients clinically and parasitologically on days 1, 2, 3, 7, 14, 21, and 28. A molecular analysis to detect mutations in the P. falciparum Kelch propeller gene (Pfk13) gene was carried out on day 0 samples. A total of 205 patients were included in the study. In Bohicon, the uncorrected adequate clinical and parasitological response (ACPR) proportion was 91.3% (95% confidence interval [CI]: 84.6–95.8%), whereas in Kandi this proportion was 96.7% (95% CI: 90.6–99.3%). Genotype-corrected ACPR proportions were 96.3% (95% CI: 90.9–99.0%) and 96.7% (95% CI: 90.6–99.3%) in Bohicon and Kandi, respectively. On day 3, 100% of patients in Bohicon and 98.9% of patients in Kandi had undetectable parasitemia. The C580Y mutation in the Pfk13 gene was not observed. AL remains effective for P. falciparum malaria in these two sites in Benin. Monitoring antimalarial efficacy and prevalence of molecular-resistance markers in Benin should be continued to allow for early detection of antimalarial resistance and to guide treatment policies.


2021 ◽  
Vol 12 ◽  
pp. 204209862110425
Author(s):  
Chenchula Santenna ◽  
Kota Vidyasagar ◽  
Krishna Chaitanya Amarneni ◽  
Sai Nikhila Ghanta ◽  
Balakrishnan Sadasivam ◽  
...  

Introduction: Remdesivir, an experimental antiviral drug has shown to inhibit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), both in vitro and in vivo. The present systematic review and meta-analysis were performed to quantify the safety and tolerability of remdesivir, based on safety outcome findings from randomized controlled trials, observational studies and case reports of remdesivir in coronavirus disease 2019 (COVID-19) patients. Methods: We have performed a systematic search in the PubMed, Google Scholar and Cochrane Library using specific keywords such as ‘COVID-19’ OR ‘SARS CoV-2’ AND ‘Remdesivir’. The study endpoints include total adverse events (AEs), serious adverse events (SAEs), grade 3 and grade 4 AEs, mortality and drug tolerability. Statistical analysis was carried out by using Revman 5.4 software. Results: Total 15 studies were included for systematic review, but only 5 randomized clinical trials (RCTs) ( n = 13,622) were included for meta-analysis. Visual inspection of the forest plots for remdesivir 10-day versus placebo and remdesivir 10-day versus 5-day groups revealed that there is a significant difference in SAEs [10-day remdesivir versus control (odds ratio [OR] = 0.55, 0.40–0.74) p = 0.0001; I2 = 0%; 10-day remdesivir versus 5-day remdesivir (OR = 0.56, 0.38–0.84) p = 0.005; I2 = 13%]. In grade 4 AEs, there is a significant difference in 10-day remdesivir versus control (OR = 0.32, 0.19–0.54) p = 0.0001; I2 = 0%, but not in comparison to 5-day remdesivir (OR = 0.95, 0.59–1.54) p = 0.85; I2 = 0%. But there is no significant difference in grade 3 AEs [remdesivir 10 day versus control (OR = 0.81, 0.59–1.11) p = 0.19; I2 = 0%; 10-day remdesivir versus 5-day remdesivir (OR = 1.24, 0.86–1.80) p = 0.25; I2 = 0%], in total AEs [remdesivir 10 day versus control (OR = 1.07, 0.66–1.75) p = 0.77; I2 = 79%; remdesivir 10 day versus 5 day (OR = 1.08, 0.70–1.68) p = 0.73; I2 = 54%)], in mortality [10-day remdesivir versus control (OR = 0.93, 0.80–1.08) p = 0.32; I2 = 0%; 10-day remdesivir versus 5-day remdesivir (OR = 1.39, 0.73–2.62) p = 0.32; I2 = 0%)] and tolerability [remdesivir 10 day versus control (OR = 1.05, 0.51–2.18) p = 0.89; I2 = 65%, 10-day remdesivir versus 5-day remdesivir (OR = 0.86, 0.18–4.01) p = 0.85; I2 = 78%]. Discussion & Conclusion: Ten-day remdesivir was a safe antiviral agent but not tolerable over control in the hospitalized COVID-19 patients with a need of administration cautiousness for grade 3 AEs. There was no added benefit of 10- or 5-day remdesivir in reducing mortality over placebo. To avoid SAEs, we suggest for prior monitoring of liver function tests (LFT), renal function tests (RFT), complete blood count (CBC) and serum electrolytes for those with preexisting hepatic and renal impairments and patients receiving concomitant hepatotoxic or nephrotoxic drugs. Furthermore, a number of RCTs of remdesivir in COVID-19 patients are suggested. Plain Language Summary Ten-day remdesivir is a safe antiviral drug with common adverse events in comparison to placebo. The rate of serious adverse events and grade 3 adverse events were significantly lower in 10-day remdesivir in comparison to placebo/5-day remdesivir. There was no significant difference in the rate of tolerability and mortality reduction in 10-day remdesivir over placebo/5-day remdesivir. There were no new safety signals reported in vulnerable populations, paediatric, pregnant and lactating women.


2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Protus Omondi ◽  
Marion Burugu ◽  
Damaris Matoke-Muhia ◽  
Edwin Too ◽  
Eva A. Nambati ◽  
...  

Abstract Background The efficacy and safety of artemether–lumefantrine (AL) and dihydroartemisinin–piperaquine (DP) against asexual parasites population has been documented. However, the effect of these anti-malarials on sexual parasites is still less clear. Gametocyte clearance following treatment is essential for malaria control and elimination efforts; therefore, the study sought to determine trends in gametocyte clearance after AL or DP treatment in children from a malaria-endemic site in Kenya. Methods Children aged between 0.5 and 12 years from Busia, western Kenya with uncomplicated Plasmodium falciparum malaria were assigned randomly to AL or DP treatment. A total of 334 children were enrolled, and dried blood spot samples were collected for up to 6 weeks after treatment during the peak malaria transmission season in 2016 and preserved. Plasmodium falciparum gametocytes were detected by qRT-PCR and gametocyte prevalence, density and mean duration of gametocyte carriage were determined. Results At baseline, all the 334 children had positive asexual parasites by microscopy, 12% (40/334) had detectable gametocyte by microscopy, and 83.7% (253/302) children had gametocytes by RT-qPCR. Gametocyte prevalence by RT-qPCR decreased from 85.1% (126/148) at day 0 to 7.04% (5/71) at day 42 in AL group and from 82.4% (127/154) at day 0 to 14.5% (11/74) at day 42 in DP group. The average duration of gametocyte carriage as estimated by qRT-PCR was slightly shorter in the AL group (4.5 days) than in the DP group (5.1 days) but not significantly different (p = 0.301). Conclusion The study identifies no significant difference between AL and DP in gametocyte clearance. Gametocytes persisted up to 42 days post treatment in minority of individuals in both treatment arms. A gametocytocidal drug, in combination with artemisinin-based combination therapy, will be useful in blocking malaria transmission more efficiently.


Sign in / Sign up

Export Citation Format

Share Document