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Back To Vidyya Rivastigmine Alleviates Behavioral Disturbances In Patients With Dementia With Lewy Bodies

Research Appears In The 15 December 2000 Issue Of The Lancet

Malarone™ (a fixed combination of atovaquone and proguanil hydrochloride) is a new antimalarial drug approved in the United States in July 2000 for both treatment and prophylaxis of malaria.

Treatment
Malarone has been shown to be highly efficacious in the treatment of uncomplicated malaria caused by Plasmodium falciparum, including malaria that has been acquired in areas with chloroquine-resistant or multidrug-resistant strains. Malarone is available in adult (250 milligram [mg] atovaquone and 100 mg proguanil hydrochloride per tablet) and pediatric (62.5 mg atovaquone and 25 mg proguanil hydrochloride per tablet) strength forms. The daily dose should be taken at the same time each day with food or milk.

For patients not on Malarone prophylaxis, Malarone is now an option for the treatment of uncomplicated P. falciparum malaria acquired in areas with chloroquine-resistant malaria. The adult dosing regimen for treatment with Malarone is four adult Malarone tablets (total dose 1 gram [g] atovaquone and 400 mg proguanil hydrochloride per day) as a single dose daily for 3 consecutive days. The pediatric dosing regimen for treatment with Malarone is based on weight, as outlined below in Table 1.

 

Table 1. Pediatric Treatment Doses of Malarone™

Body Weight*
(pounds)
Body Weight*
(kilograms)

Atovaquone/Proguanil HCl
Total Daily Dose

Dosage Regimen
2445 1120 250 mg/100 mg 1 adult tablet daily for 3
consecutive days
4667 2130 500 mg/200 mg 2 adult tablets (as a single
dose) daily for 3
consecutive days
6888 3140 750 mg/300 mg 3 adult tablets (as a single
dose) daily for 3
consecutive days
> 88 > 40 1 g/400 mg 4 adult tablets (as a single
dose) daily for 3
consecutive days
* At this time, no data are available on the safety and efficacy of Malarone for treatment of malaria in children weighing less than 11 kilograms (kg) (24 pounds [lb]), although studies are in progress.

 

Quinine (in combination with tetracycline, doxycycline, or sulfadoxine-pyrimethamine [SP] [Fansidar™]) remains the other option for the treatment of uncomplicated P. falciparum malaria acquired in areas with chloroquine-resistant malaria.

Limited data are available to date on the efficacy of Malarone for the treatment of non-falciparum species, though treatment efficacy was high in small numbers of patients with P. vivax malaria treated with Malarone. If, for example, Malarone is used to treat P. vivax malaria in a patient initially thought to have P. falciparum but for whom review of blood smears actually shows P. vivax, it should be followed by primaquine for treatment of persistent liver stages (hypnozoites). Currently, sufficient data do not exist on the efficacy of Malarone for treatment of P. ovale or P. malariae infections for recommendations to be made.

Self-Treatment
To date, sulfadoxine-pyrimethamine (SP) has been the drug recommended by the Centers for Disease Control and Prevention (CDC) for presumptive self-treatment for persons with illness suspected to be malaria who are not on efficacious prophylaxis regimens. For example, persons taking chloroquine in areas with chloroquine-resistant P. falciparum who cannot reach medical care within 24 hours should carry a self-treatment antimalarial drug.

Malarone is now a second option for self-treatment for these persons. Malarone is the drug of choice for presumptive self-treatment for travelers to areas with SP-resistant malaria, including the following areas:

  • Amazon Basin of South America
  • Southeast Asia
  • Some countries in eastern and southern Africa: specifically, Kenya, Malawi, Mozambique, South Africa, Tanzania, and Uganda.

The doses for presumptive self-treatment with Malarone are the same as the treatment doses outlined in Table 1.

Presumptive self-treatment with Malarone should not be taken by people on Malarone prophylaxis. Those on Malarone prophylaxis should use SP if in an area without SP-resistant malaria. If traveling to an area with SP-resistant malaria, travelers should be advised to consult a health care provider before traveling (CDC can provide consultation in these cases [Malaria Hotline: 888-232-3228]).

Note: CDC recommends use of malaria prophylaxis for travel to malarious areas. For travelers who either elect not to take prophylaxis or require or choose regimens that do not have optimal efficacy and plan to treat themselves only if they experience symptoms, CDC recommends these travelers use either SP or Malarone because of their good safety profiles. Presumptive self-treatment should be used only as an interim measure, and travelers should be advised to seek medical evaluation as soon as possible.

Prophylaxis
Malarone has shown good prophylactic efficacy for prevention of P. falciparum malaria, including those infections acquired in areas with chloroquine-resistant strains. Malarone has proven prophylactic activity in semi-immune persons (those who have had repeated malaria exposure because of living in malarious areas for extended periods). Recent data have shown Malarone's efficacy in persons without antimalarial immunity (that is, in persons who have had little or no past exposure to malaria and including persons who formerly lived in malarious countries but who now live in nonmalarious countries). Malarone is now one of three options (the others are mefloquine or doxycycline) for prevention of malaria when traveling to areas with chloroquine-resistant P. falciparum malaria. Of note, CDC no longer lists chloroquine/proguanil as an option for travel to areas with chloroquine-resistant P. falciparum.

The adult dosing regimen for prophylaxis with Malarone is one adult tablet daily starting 1 to 2 days before travel, taken daily during travel, and continuing daily for 7 days after leaving the malarious area. The pediatric dosing regimen for prophylaxis (which also starts 1 to 2 days before travel and continues during travel and for 7 days after leaving the malarious area) is based on weight and is outlined below in Table 2.

 

Table 2. Pediatric Prophylactic Doses of Malarone™

Body Weight*
(pounds)
Body Weight*
(kilograms)

Atovaquone/Proguanil HCl
Total Daily Dose

Dosage Regimen
2445 1120 62.5 mg/25 mg 1 pediatric tablet daily
4667 2130 125 mg/50 mg 2 pediatric tablets daily
6888 3140 187.5 mg/75 mg 3 pediatric tablets daily
> 88 > 40 250 mg/100 mg 1 adult tablet daily
* At this time, no data are available on the safety and efficacy of Malarone for prevention of malaria in children weighing less than 11 kg (24 lb), although studies are in progress.

 

Chloroquine remains the drug of choice for prophylaxis for persons traveling to areas with chloroquine-sensitive P. falciparum malaria.

Adverse Reactions
The most common adverse effects reported in people using Malarone for prophylaxis or treatment were abdominal pain, nausea, vomiting, and headache.

Pregnancy and Breast-Feeding
There are insufficient data regarding the use of Malarone during pregnancy and breast-feeding for either treatment or prophylaxis. Therefore, Malarone is not currently recommended for pregnant women unless the potential benefit outweighs the potential risk to the fetus (for example, for a pregnant woman who had acquired P. falciparum malaria in an area of multidrug-resistant strains and who could not tolerate other treatment options).

It is not known whether atovaquone is excreted into human milk. Proguanil is excreted into human milk in small quantities. Based on experience with other antimalarial drugs, the quantity of drug transferred in breast milk is insufficient to provide adequate protection against malaria for an infant. Because data are not yet available on the safety and efficacy of Malarone in children weighing less than 11 kg (24 lb), it should not be given to a woman who breast-feeds an infant who weighs less than 11 kg unless the potential benefit to the woman outweighs the potential risk to the infant (for example, for a breast-feeding woman who had acquired P. falciparum malaria in an area of multidrug-resistant strains and who could not tolerate other treatment options).

For further questions related to the use of Malarone, CDC may be contacted (Malaria Hotline: 888-232-3228).

*Use of trade names is for identification only and does not imply endorsement.


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Editor: Susan K. Boyer, RN
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