New malaria drug requires just one dose and appears twice as effective as existing regimen

New malaria drug requires just one dose and appears twice as effective as existing regimen

Scientists are reporting development of a new malaria drug that, in laboratory tests, has been twice as effective as the best current medicine against this global scourge and may fight off the disease with one dose, instead of the multiple doses that people often fail to take. A report on the drug appears in ACS' Journal of Medicinal Chemistry.

Gary Posner and colleagues explain that malaria continues to kill almost 1 million people annually. The best existing treatment is so-called artemisinin combination therapy (ACT). It requires patients to take pills every day for several days, and many patients fail to complete the regimen. As a result, these patients don't get better, and it opens the door for malaria parasites to develop resistance to ACT. To stop that from happening, the researchers developed a new type of ACT that could stop malaria in a single dose.

They describe a series of new compounds they developed that, given once, are more effective than traditional artemisinin-derived substances. One of the new compounds, when combined with mefloquine, killed off all of the parasites in some mice with just a single oral dose and allowed those mice to live almost twice as long as those treated with conventional ACT.

More information: "Malaria-Infected Mice Live Until at Least Day 30 after a New Artemisinin-Derived Thioacetal Thiocarbonate Combined with Mefloquine Are Administered Together in a Single, Low, Oral Dose", J. Med. Chem., 2012, 55 (17), pp 7892–7899. DOI: 10.1021/jm3009986

Abstract
In only three steps and in 21–67% overall yields from the natural trioxane artemisinin, a series of 21 new trioxane C-10 thioacetals was prepared. Upon receiving a single oral dose of only 6 mg/kg of the monomeric trioxane 12c combined with 18 mg/kg of mefloquine hydrochloride, Plasmodium berghei-infected mice survived on average 29.8 days after infection. Two of the four mice in this group had no parasites detectable in their blood on day 30 after infection, and they behaved normally and appeared healthy. One of the mice had 11% blood parasitemia on day 30, and one mouse in this group died on day 29. Of high medicinal importance, the efficacy of this ACT chemotherapy is much better than (almost double) the efficacy under the same conditions using as a positive control the popular trioxane drug artemether plus mefloquine hydrochloride (average survival time of only 16.5 days).

add to favorites email to friend print save as pdf

Related Stories

New process would make anti-malarial drug less costly

May 23, 2012

Scientists are reporting development of a new, higher-yield, two-step, less costly process that may ease supply problems and zigzagging prices for the raw material essential for making the mainstay drug for ...

New artemisinin-based treatment against malaria promising

Nov 08, 2011

For some time now, artemisinin, derived from a Chinese herb, has been the most powerful treatment available against malaria. To avoid the malaria parasite becoming resistant, the World Health Organisation (WHO) strongly recommends ...

Rectal artemisinins rapidly eliminate malarial parasites

Mar 28, 2008

Artemisinin-based suppositories can help ‘buy time’ for malaria patients who face a delay in accessing effective, injectable antimalarials, according to research published in the online open access journal BMC Infectious Di ...

WHO urges action as drug-resistant malaria spreads

Sep 27, 2012

The World Health Organization said Thursday that governments in the Mekong region must act "urgently" to stop the spread of drug-resistant malaria which has emerged in parts of Vietnam and Myanmar.

Recommended for you

Is Australia prepared for Ebola?

2 hours ago

Australia needs to be proactive about potential disease outbreaks like Ebola and establish a national centre for disease control.

Dallas hospital confirms first Ebola case in US

7 hours ago

A patient at a Dallas hospital has tested positive for Ebola, the first case of the disease to be diagnosed in the United States, federal health officials announced Tuesday.

First case of Ebola diagnosed in US

8 hours ago

The United States has diagnosed its first case of the deadly Ebola virus in a man who became infected in Liberia and traveled to Texas, US health officials said Tuesday.

Study finds acupuncture does not improve chronic knee pain

10 hours ago

Among patients older than 50 years with moderate to severe chronic knee pain, neither laser nor needle acupuncture provided greater benefit on pain or function compared to sham laser acupuncture, according to a study in the ...

User comments