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Drug Combinations of Atovaquone-Proguanil (AP) With ACT (APACT)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT03726593
Recruitment Status : Recruiting
First Posted : October 31, 2018
Last Update Posted : December 10, 2019
National Center for Parasitology, Entomology, and Malaria Control (CNM)
Naval Medical Research Unit-2 (NAMRU-2)
Information provided by (Responsible Party):
Armed Forces Research Institute of Medical Sciences, Thailand

Brief Summary:
Investigators are conducting this study due to recent reports of many of existing malaria drugs becoming less effective for treatment of malaria. The drugs may not always kill all the parasites, therefore not all patients with malaria are being cured. The main objective of the study is to find out which malaria drugs and what drug combinations are still effective in Cambodia, an area of multi-drug resistance where 4-5 artemisinin-based combination therapies have shown inadequate response, below that established by the World Health Organization (WHO). New drug combinations (taking more than one drug for malaria at the same time), as long as well tolerated, can provide cure in patients that harbor parasites not responsive to standard first-line medications. Human genetic testing will be done to identify patients who may have suboptimal response to treatments and to study the differences in human gene expression to explain why some persons are at higher risk of complications during treatment. Markers of drug resistance to commonly used antimalarial drugs will also be evaluated and shared with national malaria program (CNM) to better guide future malaria treatment decisions in Cambodia.

Condition or disease Intervention/treatment Phase
Plasmodium Falciparum Malaria (Drug Resistant) Drug: Artesunate and Pyronaridine Drug: Atovaquone Proguanil and Artesunate Pyronaridine Drug: Atovaquone Proguanil and Artesunate Mefloquine Phase 4

Detailed Description:
Efficacy to drugs that are currently available and new antimalarial candidates that are in development are threatened by multidrug resistant (MDR) malaria parasites, widely prevalent in Cambodia. Without effective interventions, MDR malaria can pose a substantial public health threat in the years to come. Therefore, accurate, timely and relevant data on antimalarial drug resistance is of critical importance. Prompt, effective and well-tolerated treatment remains one of the cornerstones in the malaria case management. Recent malaria outbreak in Thailand and rise of malaria cases observed in Cambodia in 2017 has brought to the forefront the urgency with which new drug candidates and new combination drug treatments must be identified; otherwise, patients may be left with ineffective treatments. Lack of available alternatives has a potential to result in significant setback to the recent gains in malaria control and malaria elimination efforts. Innovative approaches to treatment proposed here, using current ACTs in combination with non-ACT drugs, such as atovaquone-proguanil, need to be investigated to assess drug tolerability and overall efficacy when used under combination treatment. By early investment in the studies of drugs such as pyronaridine-artesunate (ASPY), in combination with other antimalarials, and drug combinations proposed under this protocol, this study will try to provide the latest evidence on the interventions that are most likely to work, even in areas of MDR, such as Cambodia, and along the Cambodia-Thai border. It is hoped that our approach for using combination treatments will not only provide more effective treatments, but it might prolong the lifespan of the remaining antimalarials and delay the spread of MDR malaria to neighboring countries.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 252 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: Randomized, open-label clinical trial to evaluate the tolerability and clinical and parasitological responses after treatment of Pf and/or mixed infections (Pf/Pv) in volunteers with uncomplicated malaria. The assignment of volunteers will be 1:1:1 for ASPY (Pyramax), AP+ASPY (AP+Pyramax), and AP+ASMQ. All study drug administration will be by directly observed therapy (DOT).
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Multicenter Therapeutic Efficacy Assessment of Pyronaridine-Artesunate (Pyramax®) and New Drug Combinations With Atovaquone-Proguanil for the Treatment of Uncomplicated P. Falciparum Malaria in Cambodia
Actual Study Start Date : October 4, 2018
Estimated Primary Completion Date : December 30, 2020
Estimated Study Completion Date : June 30, 2021

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Malaria

Arm Intervention/treatment
Experimental: ASPY
Artesunate-pyronaridine, once daily for three days, following standard weight-based dosing per drug label. All volunteers with P.f monoinfection will receive single dose of primaquine (PQ) (15 mg) for transmission blocking.
Drug: Artesunate and Pyronaridine
Standard weight based dosing

Experimental: AP+ASPY
Atovaquone-Proguanil (AP) + Artesunate-Pyronaridine (ASPY), once daily for three days, following standard weight-based dosing per drug label for each drug. All volunteers with P.f monoinfection receive single dose of PQ (15 mg) for transmission blocking
Drug: Atovaquone Proguanil and Artesunate Pyronaridine
Both drugs (AP) and (ASPY) are administered once a day, on days 0, 1, and 2.

Experimental: AP+ASMQ
Atovaquone-Proguanil (AP) + Artesunate-Mefloquine (ASMQ); ASMQ once daily for three days (D0, D1, D2), following standard weight-based dosing per drug label. Subsequently, volunteers continue their treatment with AP once daily starting on day 3, for three additional days (D3, 4, 5). All volunteers with P.f monoinfection receive single dose of PQ (15 mg) for transmission blocking.
Drug: Atovaquone Proguanil and Artesunate Mefloquine
Sequential treatment with ASMQ (on days 0, 1, and 2) followed by the treatment with AP for 3 more days (total 6 days treatment)

Primary Outcome Measures :
  1. 42-day polymerase chain reaction (PCR) corrected adequate clinical and parasitological response (ACPR), following treatment with ASPY and new drug combinations (AP+ACTs). [ Time Frame: 6 weeks ]

Secondary Outcome Measures :
  1. Prevalence of molecular markers of drug resistance [ Time Frame: Day of enrollment and day of malaria recurrence up to 8 weeks ]
  2. Drug susceptibility testing of parasite isolates against standard antimalarial drugs [ Time Frame: Day of enrollment and day of malaria recurrence up to 8 weeks ]
    Ex vivo drug susceptibility testing

  3. Pharmakokinetics of each study drug - (Cmax) [ Time Frame: multiple time points up to 8 weeks ]
    Peak plasma concentration (Cmax) for study drugs

  4. Pharmakokinetics of each study drug - (AUC) [ Time Frame: multiple time points up to 8 weeks ]
    Area under the plasma concentration versus time curve (AUC)

  5. Pharmakokinetics of each study drug - volume of distribution [ Time Frame: multiple time points throughout 6 weeks of follow up ]
    volume of distribution for study drugs

  6. Pharmakokinetics of each study drug - (T1/2) [ Time Frame: multiple time points up to 8 weeks ]
    elimination half-life (T1/2) for study drugs

  7. Kaplan Meier survival analysis of asexual blood stage parasitemia and sexual stage gametocytes [ Time Frame: 6 weeks ]
  8. Gametocyte carriage rates on days 0, 1, 2, 3, and weeks 1 through 6 for each treatment arm [ Time Frame: Days 0, 1, 2, 3, and weekly, up to week 8 ]
  9. The incidence of hepatotoxicity events for each treatment arm [ Time Frame: Day 3 and week 6 ]
    Alanine aminotransferase (ALT)>5 times the upper limit of normal (ULN) or percent of volunteers meeting the Hy's law definition (ALT or aspartate aminotransferase [AST] >3 x ULN and total bilirubin >2 x ULN) at any post-dose time point within 6 weeks of follow up

  10. Rates of treatment-related adverse events [ Time Frame: 6 weeks ]
  11. Severity of treatment-related adverse events [ Time Frame: 6 weeks ]
    Grade 1 - mild, Grade 2 - moderate, Grade 3 - severe, Grade 4- life threatening

  12. Number of participants who say they are willing to take the same drug combination in the future [ Time Frame: day 2 and week 6 ]
  13. Point efficacy with 95% Confidence Interval against blood stage malaria infection classified according to the WHO malaria treatment outcome classifications (ETF, LTF, LCTF, LPTF) [ Time Frame: 4 weeks, 6 weeks, and 8 weeks ]
  14. Incidence of Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency [ Time Frame: Enrollment ]
    Comparative incidence of G6PD deficiency in the study population as determined by G6PD rapid-diagnostic tests (RDTs) and quantitative tests, to include sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) for each of the point-of-care tests against 10%, 30%, and 60% thresholds of normal G6PD activity

  15. Number of infected mosquitos following membrane feeding [ Time Frame: Day 0, Day 3, Day 7, and on day of malaria recurrence up to 8 weeks ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years to 70 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Understands Khmer spoken language
  • Male or female (18 to 70 years old)
  • Microscopic confirmation of asexual stages of Pf or mixed infection with Pf, with baseline asexual parasite densities between 100/µL to 200,000/µL
  • Able to take oral medications
  • Hemoglobin on day of enrollment ≥9.0 g/dL
  • Agree to follow-up for the anticipated study duration, including a minimum of 3 nights at the medical treatment facility (inpatient hospitalization) and weekly follow-up visits for at least 6 weeks
  • If the volunteer is on active duty in the military, the volunteer has written permission from their supervisor or states to have been authorized by his/her supervisor or the local commander to participate; and allow study staff to contact their supervisor to confirm this information

Exclusion Criteria:

  • Known allergic reaction to any of the study drugs or history of severe intolerance to any of the antimalarials used in this study.
  • Pregnant or lactating females and females of childbearing potential who do not agree to use an acceptable form of contraception during the study period and for 6 weeks following the last dose of the study drug.
  • Symptoms of severe vomiting (inability to tolerate oral fluids or oral medications during the previous 8 hours or vomiting >3 times in the last 24 hrs).
  • Diagnosis of severe malaria
  • Abnormal liver function tests i.e AST or ALT or total bilirubin > 1.5 upper limit of normal (ULN) with nausea AND right upper quadrant abdominal pain OR jaundice on exam
  • Isolated AST or ALT or Total Bilirubin >2x ULN
  • Known significant cardiovascular, liver or renal abnormality or any other clinically significant illness, which in the opinion of the investigator would place the volunteer at significantly higher risk
  • Treatment for malaria within the last 4 weeks
  • Unable to provide informed consent
  • Judged by the investigator to be otherwise unsuitable for study participation (to include, but not limited to, taking other medications that are known to cause serious drug-drug interactions with the study drugs, as determined by the study physician, or having suspected medical condition or taking other drugs that may affect test results interpretation or put the volunteer at much higher risk)

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03726593

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Contact: Mariusz Wojnarski, MD +66-84-527-4646 MARIUSZ.WOJNARSKI.MIL@AFRIMS.ORG
Contact: Norman Waters, PhD +66 (0)2 696 2798

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Kratie Referral Hospital Recruiting
Kratie, Cambodia
Contact: Somaly Kieng, M.D    +855 72 971 755      
Contact: Chanthap Lon, M.D    855 23 881 845   
Sub-Investigator: Darapiseth Sea, MD         
Sub-Investigator: Dysoley Lek, MD         
Stung Treng Referral Hospital Not yet recruiting
Stung Treng, Cambodia
Contact: Dysoley Lek, MD         
Anlong Veng Referral Hospital Recruiting
Ânlóng Vêng, Cambodia
Contact: Phan Kong, M.A    016 51 09 09      
Principal Investigator: Chanthap Lon, MD         
Sub-Investigator: Darapiseth Sea, MD         
Sub-Investigator: Dysoley Lek, MD         
Sponsors and Collaborators
Armed Forces Research Institute of Medical Sciences, Thailand
National Center for Parasitology, Entomology, and Malaria Control (CNM)
Naval Medical Research Unit-2 (NAMRU-2)
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Principal Investigator: Mariusz Wojnarski, MD Armed Forces Research Institute of Medical Sciences (AFRIMS) Bangkok, Thailand

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Responsible Party: Armed Forces Research Institute of Medical Sciences, Thailand Identifier: NCT03726593    
Other Study ID Numbers: WR2530
First Posted: October 31, 2018    Key Record Dates
Last Update Posted: December 10, 2019
Last Verified: December 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Plan Description: The study site will maintain appropriate medical and research records for this trial until completion of the study, in compliance with Section 4.9 of International Conference on Harmonization E6 Good Clinical Practices, and institutional requirements. The investigators and other study personnel assigned from National Center for Parasitology, Entomology and Malaria Control (CNM), Armed Forces Research Institute of Medical Sciences (AFRIMS) and Naval Medical Research Center NMRC-Asia and their respective representatives are authorized access to the study data as part of their duties. The database may be shared with other collaborators, on a mutually agreed basis. Sharing and publication of the data with other parties can be done only after inter-institutional agreements are in place. The research findings may be disseminated to policy makers and other researchers for an informed decision on drug policy for the treatment of malaria.

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Armed Forces Research Institute of Medical Sciences, Thailand:
plasmodium falciparum
combination treatment
triple therapy
multidrug resistant malaria
Additional relevant MeSH terms:
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Malaria, Falciparum
Protozoan Infections
Parasitic Diseases
Atovaquone, proguanil drug combination
Antiprotozoal Agents
Antiparasitic Agents
Anti-Infective Agents
Antineoplastic Agents
Antiviral Agents
Antiplatyhelmintic Agents
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action