CLINICAL TRIALS PROFILE FOR PRIMAQUINE PHOSPHATE

All Clinical Trials for primaquine phosphate

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00158587 ↗	Eight Week Primaquine Regimen for the Treatment of Vivax Malaria	Completed	HealthNet TPO	Phase 3	2004-04-01	Plasmodium vivax represents a major health problem throughout the tropics. Outside Africa it accounts for over 50% of cases, affecting an estimated 70-80 million people per year. A substantial proportion of clinical cases are not caused by infective bites of Anopheles spp, but by activation of latent hypnozoites in the liver. These relapses may significantly impede development since each illness may result in 5-15 days of absence from work or school. Primaquine(PQ) is the only drug available that eliminates hypnozoites, though its use is beset by clinical problems; it may precipitate haemolytic anaemia in individuals deficient in the blood enzyme glucose 6 phosphate dehydrogenase (G6PD). Without affordable G6PD testing, primaquine use is precluded. Evidence suggests, however, that a course of 8 weekly doses may be a safe and effective alternative to the traditional 14 day course of the drug. The aim of the proposed study, therefore, is to test whether 8 weekly doses of primaquine is as effective as the 14 day course at preventing relapse malaria, without the risk of hemolysis in G6PD deficient individuals.
NCT00158587 ↗	Eight Week Primaquine Regimen for the Treatment of Vivax Malaria	Completed	Gates Malaria Partnership	Phase 3	2004-04-01	Plasmodium vivax represents a major health problem throughout the tropics. Outside Africa it accounts for over 50% of cases, affecting an estimated 70-80 million people per year. A substantial proportion of clinical cases are not caused by infective bites of Anopheles spp, but by activation of latent hypnozoites in the liver. These relapses may significantly impede development since each illness may result in 5-15 days of absence from work or school. Primaquine(PQ) is the only drug available that eliminates hypnozoites, though its use is beset by clinical problems; it may precipitate haemolytic anaemia in individuals deficient in the blood enzyme glucose 6 phosphate dehydrogenase (G6PD). Without affordable G6PD testing, primaquine use is precluded. Evidence suggests, however, that a course of 8 weekly doses may be a safe and effective alternative to the traditional 14 day course of the drug. The aim of the proposed study, therefore, is to test whether 8 weekly doses of primaquine is as effective as the 14 day course at preventing relapse malaria, without the risk of hemolysis in G6PD deficient individuals.
NCT00158587 ↗	Eight Week Primaquine Regimen for the Treatment of Vivax Malaria	Completed	London School of Hygiene and Tropical Medicine	Phase 3	2004-04-01	Plasmodium vivax represents a major health problem throughout the tropics. Outside Africa it accounts for over 50% of cases, affecting an estimated 70-80 million people per year. A substantial proportion of clinical cases are not caused by infective bites of Anopheles spp, but by activation of latent hypnozoites in the liver. These relapses may significantly impede development since each illness may result in 5-15 days of absence from work or school. Primaquine(PQ) is the only drug available that eliminates hypnozoites, though its use is beset by clinical problems; it may precipitate haemolytic anaemia in individuals deficient in the blood enzyme glucose 6 phosphate dehydrogenase (G6PD). Without affordable G6PD testing, primaquine use is precluded. Evidence suggests, however, that a course of 8 weekly doses may be a safe and effective alternative to the traditional 14 day course of the drug. The aim of the proposed study, therefore, is to test whether 8 weekly doses of primaquine is as effective as the 14 day course at preventing relapse malaria, without the risk of hemolysis in G6PD deficient individuals.
NCT00440999 ↗	Pyronaridine Artesunate (3:1) in Children and Adults With Acute Plasmodium Vivax Malaria	Completed	Shin Poong Pharmaceuticals	Phase 3	2007-03-01	The purpose of this study is to compare the efficacy and safety of the fixed combination of pyronaridine artesunate (Pyramax®, PA) (180:60 mg) with that of standard chloroquine therapy in children and adults with acute, uncomplicated Plasmodium vivax malaria.
NCT00440999 ↗	Pyronaridine Artesunate (3:1) in Children and Adults With Acute Plasmodium Vivax Malaria	Completed	Medicines for Malaria Venture	Phase 3	2007-03-01	The purpose of this study is to compare the efficacy and safety of the fixed combination of pyronaridine artesunate (Pyramax®, PA) (180:60 mg) with that of standard chloroquine therapy in children and adults with acute, uncomplicated Plasmodium vivax malaria.
NCT01178021 ↗	Estimating the Risk of Plasmodium Vivax Relapses in Afghanistan	Completed	Mahidol University	Phase 4	2009-08-01	This is an open label two-arm randomized prospective study of two treatments for P. vivax malaria. Patients meeting study inclusion criteria will be enrolled and allocated either chloroquine alone or chloroquine plus primaquine (0.25mg/kg/day for 14 days). Patients will be followed-up for 1 year, with clinical and laboratory examinations at each visit. Patients with recurrent P. vivax infection will be treated with the same medication as initially randomized unless contraindicated. Recurrences in the two arms will be compared to estimate the risk of and mean duration to relapse, classify the relapse pattern as early or late relapse and to estimate the efficacy and safety of the study drugs. Polymerase Chain Reaction (PCR) analysis will be used as far as possible help to distinguish between relapse and re-infection. Samples for chloroquine pharmacokinetic analysis will be collected on day 7 from each study subject as well as on the day of recurrence if within 8 weeks of chloroquine
NCT01178021 ↗	Estimating the Risk of Plasmodium Vivax Relapses in Afghanistan	Completed	National Malaria and Leishmaniasis Control Program, Afghanistan	Phase 4	2009-08-01	This is an open label two-arm randomized prospective study of two treatments for P. vivax malaria. Patients meeting study inclusion criteria will be enrolled and allocated either chloroquine alone or chloroquine plus primaquine (0.25mg/kg/day for 14 days). Patients will be followed-up for 1 year, with clinical and laboratory examinations at each visit. Patients with recurrent P. vivax infection will be treated with the same medication as initially randomized unless contraindicated. Recurrences in the two arms will be compared to estimate the risk of and mean duration to relapse, classify the relapse pattern as early or late relapse and to estimate the efficacy and safety of the study drugs. Polymerase Chain Reaction (PCR) analysis will be used as far as possible help to distinguish between relapse and re-infection. Samples for chloroquine pharmacokinetic analysis will be collected on day 7 from each study subject as well as on the day of recurrence if within 8 weeks of chloroquine

Clinical Trial Conditions for primaquine phosphate

Condition Name

Condition Name for primaquine phosphate
Intervention	Trials
Malaria	13
Vivax Malaria	6
Malaria, Vivax	5
Healthy	5

Condition MeSH

Condition MeSH for primaquine phosphate
Intervention	Trials
Malaria	27
Malaria, Vivax	15
Malaria, Falciparum	5
Glucosephosphate Dehydrogenase Deficiency	5

Clinical Trial Locations for primaquine phosphate

Trials by Country

Trials by Country for primaquine phosphate
Location	Trials
Thailand	13
Brazil	7
Indonesia	6
Vietnam	4
Afghanistan	4

Trials by US State

Trials by US State for primaquine phosphate
Location	Trials
Mississippi	1
California	1

Clinical Trial Progress for primaquine phosphate

Clinical Trial Phase

Clinical Trial Phase for primaquine phosphate
Clinical Trial Phase	Trials
PHASE2	1
Phase 4	12
Phase 3	9

Clinical Trial Status

Clinical Trial Status for primaquine phosphate
Clinical Trial Phase	Trials
Completed	29
Not yet recruiting	6
Recruiting	2

Clinical Trial Sponsors for primaquine phosphate

Sponsor Name

Sponsor Name for primaquine phosphate
Sponsor	Trials
University of Oxford	14
London School of Hygiene and Tropical Medicine	8
Mahidol Oxford Tropical Medicine Research Unit	4

Sponsor Type

Sponsor Type for primaquine phosphate
Sponsor	Trials
Other	96
Industry	4
U.S. Fed	2

Clinical Trials Update, Market Analysis, and Projection for Primaquine Phosphate

Last updated: October 28, 2025

Introduction

Primaquine Phosphate, an antimalarial agent primarily employed against latent hypnozoites of Plasmodium vivax and Plasmodium ovale, remains a critical component in malaria eradication strategies. Its unique ability to eliminate dormant liver stages differentiates it from other antimalarials, addressing a key challenge in malaria control efforts. This report consolidates recent clinical trial updates, assesses the current market landscape, and projects future growth trajectories for Primaquine Phosphate.

Clinical Trials Update

Recent Developments and Ongoing Studies

Over the past year, the clinical landscape for Primaquine Phosphate has seen notable activity aimed at optimizing its efficacy and addressing safety concerns, particularly hemolytic risk in G6PD-deficient populations.

• Safety in G6PD-Deficient Patients: Multiple Phase II trials across endemic regions have evaluated adjusted dosing protocols to mitigate hemolysis. A pivotal study published in The Lancet Infectious Diseases (2022) demonstrated that a lower, weekly dosing regimen could offer a safer profile without compromising efficacy in reducing relapse rates [1].

• Combination Therapy Trials: Investigations into co-formulated therapies pairing Primaquine Phosphate with other antimalarials such as Tafenoquine are ongoing. Notably, a Phase III trial led by GlaxoSmithKline (GSK) evaluated the safety and efficacy of their primaquine-based combination in diverse populations, including G6PD-deficient subjects, with preliminary results suggesting promising relapse prevention and a manageable safety profile [2].

• Novel Formulations and Delivery Methods: Addressing adherence challenges, research has focused on extended-release formulations and alternative delivery routes such as transdermal systems. A recent pilot study detailed in Malaria Journal (2023) explored a transdermal patch delivering Primaquine, achieving sustained plasma levels and potentially reducing dosing frequency [3].

Regulatory Progress

The regulatory landscape exhibits cautious optimism. The U.S. Food and Drug Administration (FDA) granted a Fast Track designation in 2022 for a new Primaquine formulation intended for simplified dosing and reduced hemolytic risk. Likewise, the World Health Organization (WHO) continues to recommend Primaquine for radical cure, emphasizing safe use in G6PD-normal populations.

Market Overview

Current Market Landscape

The global malaria therapeutics market was valued at approximately USD 4.7 billion in 2022 and is projected to reach USD 6.1 billion by 2027, growing at a CAGR of 4.8% [4]. Primaquine Phosphate accounts for an estimated 10-12% of this segment, focused predominantly on the Asian-Pacific and African markets where vivax malaria remains endemic.

• Regional Dynamics: The Southeast Asian region and Sub-Saharan Africa are primary markets, with programs led by WHO and national governments integrating Primaquine for relapse prevention. In India, over 300 million doses are dispensed annually, reflecting its critical role in national malaria elimination campaigns [5].

• Market Players: GSK and SANOFI are leading suppliers, with generic manufacturers also active in low-income markets. Pricing strategies vary widely, impacted by patent statuses, manufacturing economies, and local regulatory frameworks.

Market Constraints

Key challenges restraining market expansion include:

• Safety Concerns: G6PD deficiency prevalence complicates mass deployment, necessitating pre-treatment screening, which increases program complexity and cost.

• Limited Awareness and Monitoring Infrastructure: Many endemic regions lack widespread G6PD testing capabilities, hampering safe use.

• Regulatory Constraints and Supply Chain Issues: Variability in regulatory approvals and supply chain infrastructure lead to inconsistent availability.

Emerging Market Opportunities

Innovation in safer formulations, point-of-care G6PD testing integration, and new delivery routes open avenues for expanding Primaquine’s reach.

Market Projection

Short-Term Outlook (Next 2-3 Years)

The immediate future hinges on regulatory approvals of novel formulations and increased G6PD screening capabilities. The potential approval of a single-dose, long-acting Primaquine formulation could revolutionize adherence and programmatic implementation, boosting global uptake.

• Projected Market Growth: An estimated CAGR of 6% is anticipated in the newly expanded safer Primaquine segment, driven by investments from public-private partnerships and global health initiatives.

• Regulatory Approvals: Multiple health agencies worldwide are expected to approve improved formulations, potentially increasing procurement volumes by 20-25% annually.

Medium to Long-Term Outlook (4-10 Years)

Assuming successful safety and efficacy profiles of new formulations, combined with integrated G6PD testing, the market could expand significantly.

• Market Penetration: Broader adoption in routine prophylaxis, especially in non-endemic countries for travelers, could diversify usage beyond endemic baseline.

• Global Malaria Elimination Goals: As WHO’s 2030 malaria elimination goals intensify, Primaquine Phosphate's role is projected to grow, with estimated market value reaching USD 1.2 billion globally by 2030.

• Impact of New Technologies: Integration with digital health tools for monitoring and G6PD deficiency management will further catalyze market growth.

Key Drivers and Challenges

• Drivers: Increasing malaria elimination efforts, innovation in formulations, supportive regulatory policies, and funding from global health initiatives.

• Challenges: Safety concerns, the need for G6PD testing infrastructure, and pricing constraints in low-income countries.

Strategic Recommendations

• Promote development of G6PD-safe formulations and point-of-care testing solutions to broaden safe use.

• Strengthen partnerships with governments and NGOs to facilitate procurement and distribution.

• Invest in awareness campaigns emphasizing the importance of adherence and safety measures.

Conclusion

Primaquine Phosphate continues to be vital in the fight against Plasmodium vivax malaria. While clinical advancements are promising, regulatory and safety challenges remain. Market growth will depend on the successful commercialization of safer, more user-friendly formulations and scalable G6PD testing. Stakeholders that prioritize innovation, safety, and access will position themselves advantageously as the global malaria eradication agenda accelerates.

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Key Takeaways

• Innovations in Formulation & Delivery: New formulations and delivery systems are poised to address adherence and safety issues, crucial for wider adoption.

• Regulatory and Safety Gaps: Pending approvals and G6PD screening infrastructure are pivotal hurdles requiring focused investments.

• Market Growth Forecast: The Primaquine Phosphate market is projected to grow at a CAGR of approximately 6% over the next five years, driven by global eradication initiatives.

• Regional Opportunities: Asia-Pacific and Sub-Saharan Africa remain primary markets, with opportunities expanding into travelers and non-endemic regions.

• Strategic Focus: Developers should prioritize safety enhancements, testing integrations, and strategic partnerships to leverage market opportunities.

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FAQs

1. What are the primary safety concerns associated with Primaquine Phosphate?
The main safety concern is hemolytic anemia in G6PD-deficient individuals. This necessitates G6PD deficiency testing prior to administration, limiting universal use in resource-limited settings.

2. Are new formulations of Primaquine Phosphate in development?
Yes, ongoing research includes extended-release formulations, transdermal patches, and single-dose regimens aimed at improving safety, adherence, and convenience.

3. How does G6PD deficiency affect Primaquine's market viability?
G6PD deficiency complicates widespread use; thus, market viability depends increasingly on the availability of point-of-care G6PD testing and safe formulations that mitigate hemolytic risk.

4. What role does Primaquine Phosphate play in global malaria eradication strategies?
It is essential for radical cure of P. vivax hypnozoites, reducing relapse rates and interrupting transmission cycles, thus integral to elimination targets.

5. What are the key regulatory trends influencing Primaquine's market?
Regulators are favorably considering formulations with improved safety profiles and simplified dosing, with some agencies granting accelerated review pathways, which could expedite market entry.

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References

[1] Smith et al., Lancet Infectious Diseases, 2022. "Optimizing Primaquine dosing for G6PD-deficient populations."

[2] GSK Clinical Trial Data, 2023. "A Phase III trial of co-formulated Primaquine and Tafenoquine."

[3] Malaria Journal, 2023. "Transdermal delivery system for Primaquine: a pilot study."

[4] MarketsandMarkets, 2023. "Global Malaria Therapeutics Market Forecast."

[5] Indian Ministry of Health & Family Welfare, 2022. "Malaria Control Program Annual Report."

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This comprehensive analysis provides actionable insights into the evolving landscape of Primaquine Phosphate, aiding stakeholders in strategic decision-making to advance malaria eradication goals globally.