dornase alfa

Dornase alfa is an inhaled drug for treating cystic fibrosis, a lung disease which is the most common fatal genetic disease in developed countries. The lungs continually secrete fluid into the airways to keep them moist. In cystic fibrosis, the fluid becomes thick because the amount of water it contains is reduced. The thickened fluid is difficult to cough up or spit out. It blocks the airways, making breathing difficult and promoting the growth of bacteria and infection.

Infection destroys the tissues of the lungs, and it is the slowly progressive destruction of the lungs that is the major cause of disability and death in children with cystic fibrosis. The thick fluid contains high concentrations of deoxyribonucleic acid (DNA). Dornase alfa is a genetically engineered form of the human enzyme, deoxyribonuclease or DNAse. Dornase alpha breaks down the DNA and thereby reduces the thickness of the fluids. Dornase alfa was approved by the FDA in 1993.

The most common side effects of dornase alfa include:

• voice alteration,
• sore throat,
• laryngitis,
• rash,
• chest pain,
• red eyes,
• cough,
• nasal congestion,
• shortness of breath,
• stomach upset,
• and fever.

The recommended dosage, in most cystic fibrosis patients, is one 2.5 mg single-dose ampule inhaled once daily using a recommended jet nebulizer connected to an air compressor system or eRapid™ Nebulizer System.

Pulmozyme should only be used with the approved nebulizers and appropriate compressors. See the prescribing label for more information.

Do not use any other inhaled medicines in the nebulizer at the same time. Keep all other inhaled medicine systems completely separate from Pulmozyme.

Drug interaction studies have not been conducted. Dornase alfa is compatible with standard cystic fibrosis therapies including oral, inhaled and/or parenteral antibiotics, bronchodilators, enzyme supplements, vitamins, oral or inhaled corticosteroids, and analgesics.

No damage has been noted to fetuses of pregnant animals exposed to high doses of dornase alfa. However, there are no studies in women. Therefore, physicians must weigh potential risks with the expected benefits of therapy when deciding whether or not to use dornase alpha in pregnancy.

It is not known whether dornase alpha is secreted in human milk. At most, very little dornase alfa would be expected in human milk after long-term aerosol use. However, because many drugs are secreted in human milk, physicians must still use caution when they consider the use of dornase alpha in nursing women.

What preparations of dornase alpha are available?

Single-use ampules; 2.5 ml (1 mg/ml)

How should I keep dornase alpha stored?

Dornase alfa must be kept in a refrigerator at 2 C to 8 C (36 F to 46 F) and protected from direct sunlight. The solution should be thrown away if it is cloudy or discolored. Since the ampule does not contain a preservative, the entire contents of the ampule must be used or thrown away after it is opened.