An important therapeutic option has arrived for the nearly 10 million adults and five million children in America who live with the distressing disease of singular asthma, as the United States Food and Drug Administration has cleared for marketing Singulair(R) (montelukast sodium), a new once a day pill for the prevention and chronic treatment of singular asthma.
Of the new class of singular asthma medicines called leukotriene blockers, Singular is the first intended for both adults and children as young as six and the first developed for once daily use. Singular works by blocking leukotrienes, powerful substances that are involved in the inflammatory process associated with asthma.
Singular has been studied for the long-term control of singular asthma, but is not intended for the relief of acute singular asthma episodes or symptoms. It should not be used to relieve an singular asthma episode or be abruptly substituted for oral or inhaled corticosteroids. Patients should have quick-relief medicines available to treat worsening asthma.
"For anyone, but particularly for a child, having asthma can be devastating. Not only is asthma extremely limiting, but the child must also learn to use inhalers and other special equipment to take his or her medicine. Often they must remember to do it several times a day," said Beth Seidenberg, M.D., Executive Director, Clinical Research, Merck Research Laboratories. "Singular may simplify the burden of asthma control, especially for many asthmatic children and their parents."
In clinical studies, Singular improved asthma control in many patients by significantly decreasing asthma attacks, preventing daytime and night-time asthma symptoms, and reducing reliance on other asthma medicines, such as quick-relieving bronchodilators. It also allowed many patients to reduce gradually their use of inhaled steroids.
Inhaled steroids are the most commonly used drugs for long-term asthma control, but they can be difficult to use and have been associated with potential side effects, particularly at high doses and with long-term use. However, Singular may not completely eliminate the need for inhaled or systemic corticosteroids. Patients should not decrease or stop taking other asthma medicines unless instructed by their doctor.
Singular is not a steroid and in clinical studies was as well-tolerated as placebo. It will be available in pharmacies by mid-March as both a 10 mg tablet for adolescents and adults and a 5 mg cherry-flavoured chewable tablet for children ages six to 14.
The marketing clearance of Singular is based on clinical studies that measured efficacy and safety in more than 3,000 adults and children, aged six to 14 years. Singular should be taken in the evening and may be taken with or without food.
Side effects with Singular were usually mild and generally did not require patients to stop taking Singular. Side effects seen in adults and children during the clinical trials were similar for the groups treated with Singular and for those treated with placebo. The most commonly reported side effects in adults for both placebo and Singular were headache, influenza and abdominal pain. There was no increase in side effects with extended treatment and no clinically-meaningful drug interactions.
Patients should take Singular daily as prescribed even when they have no symptoms, as well as during periods of worsening asthma. Singular should not be used to relieve an acute asthma episode. Singular should not be used by itself for the treatment and management of exercise-induced asthma. Patients should be advised to continue using their usual regimen of bronchodilators before exercise.
In clinical trials, 81 percent of adult patients taking Singular reported that they felt better (vs. 67 percent taking placebo and as-needed bronchodilators), and 81 percent of parents reported that their children (aged six to 14 years) with asthma felt better (vs. 71 percent taking placebo and as-needed bronchodilators).
Asthma-related outcomes for adults and adolescents (15 and older) with mild to moderate asthma taking Singular improved significantly. When compared to placebo and as-needed bronchodilators, an analysis of 1,325 patients (795 on Singular and 530 on placebo) showed that patients treated with Singular and as-needed bronchodilators :
- Suffered 37 percent fewer asthma attacks (11.6 percent in the group treated with Singular vs. 18.4 percent in the placebo group). Asthma attack was defined as an emergency room visit, hospital admission, unscheduled doctor's office visit or a need for treatment with oral, intravenous or intramuscular corticosteroids.
- Experienced 42 percent more days and nights with asthma under control (38.5 percent in the group treated with Singular vs. 27.2 percent in the placebo group). Days with singular asthma under control were defined as days without any of the following : nocturnal awakening, use of more than two puffs of a bronchodilator, or an asthma attack.
The incidence of asthma is rising at an alarming rate in the United States. According to the National Center for Health Statistics, between 1990 and 1994 the number of people suffering from asthma increased from 10.4 million to 14.6 million. Asthma affected approximately 4.8 million children under the age of 18 in 1994. It is the leading cause of school absenteeism attributed to chronic conditions and the leading cause of hospitalisation for chronic illness among children under 15. Asthma causes approximately 5,000 deaths each year in the U.S.