Cystic Fibrosis Foundation

Antioxidant Therapies for Cystic Fibrosis

You hear a lot about antioxidants and how they can prevent disease. In recent years, the Cystic Fibrosis Foundation has funded both laboratory and pre-clinical research studies on antioxidant therapies for cystic fibrosis (CF).

Antioxidants may have a role in the slowing or prevention of CF lung disease. A healthy diet, including fruit and vegetables supplemented by fat-soluble vitamins, can boost the CF patient’s antioxidant protection.

In people with CF, however, the digestion does not always guarantee proper nourishment since mucus tends to clog the pancreas. Therefore, researchers are looking for alternative ways to deliver antioxidants to CF patients. One compelling strategy is to supplement the fat-soluble vitamins A, D, E and K. Another strategy is to administer oral N-acetylcysteine, or NAC, which is a building block for the antioxidant glutathione. Below is a summary of things you should know about both approaches.

New Antioxidant Strategies

Yasoo Health is developing a novel vitamin and nutritional supplement, which is formulated to be well absorbed in people with CF. In addition to the novel formulation, it also contains vitamins and micronutrients not currently found in CF vitamins.

The results of a Phase 1 clinical trial were encouraging—with respect to enhanced absorption—and further work is planned to move the compound forward as a CF-specific vitamin. The CF Foundation awarded Yasoo Health close to $1 million in early 2006 to further evaluate and develop a commercial vitamin product for CF.
Investigators at Stanford University have evaluated the safety and efficacy of oral N-acetylcysteine (NAC) supplementation in CF patients. This supplement was studied because it provides the body with the essential building blocks for glutathione—a naturally occurring antioxidant helps maintain the the immune system. It also plays a role in protecting the lungs against damage from germs and pollutants. Scientific evidence suggests CF patients have reduced levels of glutathione in their lungs.

In the small Phase 1 NAC study, no safety concerns were identified and white blood cell and blood glutathione levels were increased. Somewhat surprisingly, sputum markers of inflammation were significantly reduced.

Based on these encouraging results, a Phase 2 study is now underway, which will further our understanding of the safety and efficacy of oral NAC supplementation in CF. Additional approaches are being pursued to increase glutathione levels using an oral compound.

Inhaling glutathione as a mist has been studied in two small clinical trials with variable results. Inhaled glutathione is a more complicated and time-consuming compound to develop because it would require full approval by the Food and Drug Administration as a drug.

Cystic Fibrosis Foundation Therapeutics (CFFT), the drug discovery and development affiliate of the CF Foundation, has funded a European investigator to perform a larger clinical trial to determine if inhaled glutathione is both safe and effective.

Until the safety, dosage, and possible benefits have been addressed in a large clinical trial, it is not recommended that people with CF use glutathione as a therapy. The CF Foundation recommends that patients continue with their current therapies as prescribed by their CF physician.

Any therapy that has not been thoroughly studied in patients could have unknown and dangerous side effects. Any changes in a therapeutic regimen, such as adding or stopping treatments, should be discussed with the CF care center physician responsible for the patient’s care.

Trials of inhaled nacystelyn (NAL) also are being conducted. Since NAL is a salt derived from NAC, it shares many properties with inhaled glutathione. Galephar Pharmaceutical Research, Inc. has sponsored a series of Phase 1 and Phase 2 clinical trials in Europe and the United States to test its safety and efficacy in CF patients. The results are mixed, so additional clinical trials are planned.

The CF Foundation is committed to moving new effective antioxidant therapies forward as quickly as possible. The CF Foundation continues to work with physicians and scientists to design and start a double-blind, placebo-controlled clinical trial of glutathione in people with CF. Participation of people with CF in upcoming clinical trials will help speed up the development of new therapies to treat and ultimately cure CF.

In the meantime, The CF Foundation has more than two dozen potential CF therapies in various stages of pre-clinical development and clinical trials—more therapies than at any other time in CF history. Any one of these potential treatments, if successful, could make a difference in the lives of people with CF. Some therapies treat the symptoms of CF, while others treat the basic defect in CF cells. The CF Foundation will continue to work on these potential therapies forward while also adding new therapies to the development pipeline.

Updated 10/13/06