Malaria prophylaxis for aircrew: safety of atovaquone/proguanil in healthy volunteers under aircraft cabin pressure conditions.

BACKGROUND Because malaria in endemic areas presents a serious threat to the health of aircrew, optimal prevention is important. An effective and safe prophylactic antimalarial drug is needed. The combination of 250 mg atovaquone with 100 mg proguanil HCl (atovaquone/proguanil, or A/P) has shown good prophylactic efficacy and tolerance for prevention of falciparum malaria. However, medication for use by aircrew on duty is subject to approval by national and international aviation authorities, who require convincing evidence that the treatment has no negative effects on the flight performance of crews. The purpose of the present study was to evaluate the risk of detrimental effects of atovaquone/proguanil on flight-related performance and alertness in healthy subjects under conditions of aircraft cabin pressure. METHODS A randomized, double-blind crossover study was conducted in which 24 subjects were enrolled to use A/P and placebo, each in a 14-day prophylactic dosing regimen with a 21-day washout phase. Vigilance, alertness, complex information processing, and sleepiness were assessed in a hypobaric chamber at 75.2 kPa, which equals the lower limit of commercial aircraft cabin pressure. Furthermore, duration and quality of sleep at home were recorded during the 14 days of drug administration. RESULTS Twenty-two subjects completed the study. No significant differences were found between the effects of placebo and A/P on vigilance, alertness, complex information processing, sleep duration and quality, and the occurrence of adverse effects. CONCLUSIONS In-flight performance and alertness of aircrew will not be affected by the prophylactic use of A/P during a period of 14 days.