MalariaPhase 3PRIMUSNCT07468526
An Ultra-short Course of Primaquine for the Radical Cure of Vivax Malaria
A Phase 3 study testing High dose ultra short Primaquine in people with Malaria, run by Menzies School of Health Research at 5 sites in 4 countries.
Trial summary
Current treatment regimens to prevent relapsing malaria are too long. A shorter higher dose treatment could improve treatment outcomes, but this needs to be balanced against increased risk of side effects. Read more about this study
- Who is it for?
- Ages 5 years and older
- Conditions the study is for
- Malaria
- What is being tested?
- High dose ultra short Primaquine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 1,019 participants
- Where
- 5 sitesin 4 countries
- Study dates
- 1 Jun 2026to 1 Apr 2028
- Phase
- Phase 3
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 5 years and older
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- P. vivax peripheral parasitaemia as determined by microscopy
- G6PD normal status (G6PD activity ≥70% of the site specific adjusted male median as determined by the Standard G6PD (SD Bioline, ROK))
- Fever (temperature ≥37.5°C) or history of fever in the preceding 48 hours,
- Age ≥5 years
- Bodyweight ≥14kg
- Living in the study area and willing to be followed-up for six months
Who cannot join
- Signs or symptoms of severe malaria,
- Anaemia (defined as Hb <8g/dl) and measured by the Standard G6PD
- Pregnant or lactating
- Blood transfusion within the preceding four months
- Regular or recent use (last month) of tafenoquine, primaquine or dapsone
- Known hypersensitivity to any of the study drugs
Trial locations and contacts
5 sites in 4 countries. Contact the study team or a site near you to ask about taking part.
5 sites in 4 countries
Ethiopia2 sites
Arba Minch University
Arba Minch, Arba Minch
Dr Tamiru Degaga, +252911704767, drtamshib1@gmail.com
Dr Tamiru Degaga
Jimma University
Jimma, Jimma
Dr Daniel Yilma, +251471111458, danielyilmab@gmail.com
Dr Daniel Yilma
Indonesia1 site
Universitas Sumatera
Bandar Lampung, Lampung
Dr Ayodhia Pitaloka Pasaribu, Professor, +628126024392, ayodhia@usu.ac.id
Dr Ayodhia Pitaloka Pasaribu
Pakistan1 site
Aga Khan University, Karachi
Karachi, Thatta
Dr Asim Beg, Professor, +923002028490, masim.beg@aku.edu
Dr Asim Beg
Papua New Guinea1 site
Papua New Guinea Institute of Medical Research
Port Moresby, Magang
DR Moses Laman, +6754340208, moses.laman@pngimr.org.pg
Dr Moses Laman
About this study
Official title: An Ultra-short Course of Primaquine for the Radical Cure of Vivax Malaria (PRIMUS)
Current treatment regimens to prevent relapsing malaria are too long. A shorter higher dose treatment could improve treatment outcomes, but this needs to be balanced against increased risk of side effects. Recent data from a trial in children in Papua New Guinea (PNG) suggests a shortened treatment of 3 days is safe and effective. Our multicentre trial will assess the safety and efficacy of an ultra-short primaquine course. This trial is expected to directly influence global treatment policies.
- Conditions
- Malaria
- Being tested
- High dose ultra short Primaquine, Placebo
- Keywords
- An ultra-short course of primaquine for the radical cure of vivax malaria, PRIMUS
- Medical subject headings
- Malaria
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
High dose ultra short PrimaquineDrug
High-dose, ultra-short primaquine (PQ3.5): 7mg/kg total dose given as 1mg/kg twice daily over 3.5 days (day 0, 1 and 2 morning and evening doses, and day 3 morning dose) followed by placebo as morning doses on day 4, 5 and 6.
PlaceboOther
Matching placebo administered according to the arm schedule. Morning dose on Days 4-6 for PQ3.5 arm and Evening dose on the first 3 days for PQ 7 arm).
| Study group | Role | What they receive |
|---|---|---|
| High-dose Short-course Primaquine (PQ7) | Active comparator | Participants in this arm will receive a high-dose, short-course primaquine regimen (PQ7), consisting of a total dose of 7 mg/kg administered as 1 mg/kg once daily in the morning for 7 days (Day 0-6). A matching placebo will be given in the evening on the first three days (Day 0-2). Receives: Drug: High dose ultra short Primaquine; Other: Placebo |
| High dose ultra- short course Primaquine (PQ 3.5) | Experimental | Participants in this arm will receive a high-dose, ultra-short primaquine regimen (PQ3.5), consisting of a total dose of 7 mg/kg administered as 1 mg/kg twice daily for 3.5 days (Day 0-2 morning and evening doses, and Day 3 morning dose). A matching placebo will be given as the morning dose on Days 4-6. Receives: Drug: High dose ultra short Primaquine; Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence risk of any recurrent vivax parasitaemia within 4 months.
The incidence risk (time to first event) of any recurrent P. vivax parasitaemia within 4 months as determined by microscopy
Measured: 4 Months
Secondary outcomes (8)
The incidence risk of any P. vivax parasitaemia within 6 months.
The incidence risk (time to first event) of any P. vivax parasitaemia within 6 months as determined by microscopy
Measured: 6 months
Incidence of haemoglobin drop >25% to <7g/dl within 14 days of treatment.
Number of participants experiencing a haemoglobin decrease of >25% from baseline resulting in Hb<7g/dl
Measured: 0-14 days
Incidence of moderate anaemia within 14 days after starting primaquine
Number of participants developing haemoglobin >=5g/dl and <7g/dl within 14 days after treatment initiation
Measured: 0-14 days
Incidence of severe anaemia within 14 days after starting Primaquine
Number of participants developing haemoglobin <5g/dl within 14 days of treatment initiation.
Measured: 0-14 days
• The proportion of patients requiring blood transfusion within the 6 months follow up period.
Participants requiring transfusion due to haemolysis or severe anaemia
Measured: 6 months
The incidence risk of symptomatic P. vivax parasitaemia within 4 months.
The incidence risk (time to first event) of symptomatic P. vivax parasitaemia within 4 months as determined by microscopy.
Measured: 4 months
Proportion of adverse events within 14 days.
The number and proportion of adverse events within 14 days after start of treatment
Measured: 14 days
The number and proportion of serious adverse events.
The number and proportion of serious adverse events.
Measured: 6 Months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Mar 2026
- Study start1 Jun 2026 (estimated)
- Primary completion1 Dec 2027 (estimated)
- Study completion1 Apr 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for MalariaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Health care facility based, randomised, controlled, double blinded, trial with 2 arms
- Masking
- Triple blind
- Who is masked
- Participant, Care provider, Investigator
- Enrolment
- 1,019 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Menzies School of Health Research
- Sponsor type
- University, hospital or other
- Collaborators
- Curtin University, University of Melbourne, Papua New Guinea Institute of Medical Research, Arba Minch University, Jimma University, Universitas Sumatera Utara, Aga Khan University, PathWest Laboratory Medicine WA
- Responsible party
- Sponsor
- Investigators
- Kamala Thriemer, Professor, Principal investigator, Menzies School of Health Research
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07468526
- Sponsor's protocol ID
- PRIMUS
- Other IDs
- GTN2042278
- Acronym
- PRIMUS
- Status last verified
- Jan 2026
- First submitted
- 13 Jan 2026
- Last updated
- 12 Mar 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: De-identified individual participant data (IPD) underlying the results reported in this trial will be shared. This will include baseline characteristics, outcome measures, and adverse events data. Data will be available beginning \[6-12 months\] after publication of the primary results, and will be shared with qualified researchers upon reasonable request, following approval of a research proposal and completion of a data access agreement. Supporting documents such as the study protocol and statistical analysis plan will also be provided.