The first new drug in half a century to target malaria parasites in one of their best hideouts is showing encouraging results.
The researchers developing the drug, called tafenoquine, said today that data from a recently completed phase II trial were promising enough that they will soon start a phase III trial—the last step before asking drug regulators for approval.
Tafenoquine kills the malaria parasite when it is lurking in liver cells, in a form called the hypnozoite, or “sleeping parasite.”
Hypnozoites don’t cause any symptoms and are impossible to detect with blood tests. But when triggered by signals that aren’t fully understood,
they can reactivate to cause a new bout of malaria—which can then be picked up by mosquitoes and passed on to new victims.
Five species of Plasmodium can cause malaria in humans. Two of them—Plasmodium vivax, which is widespread, and the relatively rare P. ovale—can form hypnozoites.
This ability to hide is one of the things that makes P. vivax so difficult to eliminate from a region.
Now, the only treatment that can cure vivax malaria—hiding parasites and all—is a 14-day course of a drug called primaquine, which was developed in the 1940s.
It works fairly well, but it is difficult for people who don’t feel ill to complete the whole 2 weeks.
“The compliance with the current regimen is really a problem,” says JP Kleim, director of clinical development for the pharmaceutical company GlaxoSmithKline (GSK).
“The acute malaria is gone after a few days [of treatment],” so patients’ motivation to continue taking drugs is low.
That’s why GSK decided to develop tafenoquine, together with the Medicine
s for Malaria Venture, a Geneva-based nonprofit. The partners launched a trial in 2011 to test whether a single dose of tafenoquine could work as well as the 2-week course of primaquine.
The data, presented today at the American Society of Tropical Medicine and Hygiene Annual Meeting in Washington, D.C., suggest that a single dose works very well.
The trial involved 329 patients in Brazil, India, Thailand, and Peru. In patients who received either a 300 mg or 600 mg dose of the drug, 90% had no relapses after 4 months.
The partners will now go forward with a phase III trial, testing the safety and efficacy of the 300 mg dose in 600 patients, says Marcus Lacerda of the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado in Manaus, Brazil, who helped coordinate the study and presented the results at the meeting today.
A single-dose drug would be a huge advantage in the fight against vivax malaria, says Ric Price of the Menzies School of Health Research in Darwin, Australia, and the University of Oxford in the United Kingdom. “One of the biggest challenges we face is how can we adequately and reliably treat the hypnozoite stage.”
Posted by KH111 (Member # 25829) on :
This is most promising.
I treated with mepron/zith for 6 months and artiminisin and also did a round of CoArtemen in 2004. Have no problems since, but always worried that it could come back. I am saving this info.
Good find!!
Posted by GretaM (Member # 40917) on :
Darn bugs!
Hypnozoites... Those sneaky sneaky parasites!
Great info in this post! Thanks Posted by Carmen (Member # 42391) on :
The absolute cure for malaria is MMS and you are cured in less than two days. One or two doses is all that is requried. 100% cure across the board. Why mess with anything else.
Thanks for posting. This drug has been in the works for several years and may be a new alternative for babesia -- but obviously it is still years in the future with the slowness of clinical trials for drugs.
Carmen -- I am sure the reason for posting this info on the forum is because of the potential uses for babesia treatment. Malaria is much much easier to cure than babesia although they are similar parasites. -----------------------------------------------
I just got my copy of the new book -- Solving the Mystery of Lyme and Chronic Disease. Was not surprised, but was disappointed, that the section titled New Discoveries on the Horizon in regard to babesia really doesn't cover anything new to members of this forum -- Beta blockers, heparin, curcumin, stephania and cryptolepis were mentioned.
But what did actually surprise me is that the doses of commonly used babesia meds discussed in the book were quite a bit lower than the ones hubby was taking -- for example only 4 malarone daily versus 6 and only 3 capsules of artemesia daily versus much higher doses of artemisinin, and the lariam dose hubby took was 4 pills weekly versus 1 pill weekly. I have previously mentioned that the dose of cryptolepis hubby found effective was 3 times the normal dose -- 1 tablespoon 3 times daily versus 1 teaspoon 3 times daily.
I was encouraged that the book suggested combining and rotating different babesia meds and herbs which is what seemed to help hubby.
But there was no mention of using flagyl, alinia or ivermectin in babesia treatment.
Also -- probably due to the publishing timeframe -- even though the book mentioned targeting apicoplast structures -- there was no mention of using the meds cipro or rifampin for this purpose. PMID 22391527
Bea Seibert
[ 11-15-2013, 04:16 PM: Message edited by: seibertneurolyme ]
Posted by Pocono Lyme (Member # 5939) on :
You're right Bea. I've been following Tafenoquine for years.
I do believe it does take multiple combinations and change ups to rid babesia or at least put it to bed.
I got relief from the teeth chattering chills with Mepron/Zith but still had other symptoms of it.
I also gained some ground with larium but later lost what I had gained.
I think what got me over the hump was a few rounds of Coartem and Primaquine.
Hopefully the Tafenoquine will help lessen the suffering in the future.
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