*****FROM ABC NEWS MEDICAL UNIT*****
Hi ni-jo and thank you for your question. Here's an answer from Cori Daines, M.D., Pediatric Pulmonologist, Arizona Respiratory Center, Univ. of Arizona College of Medicine:
Transfer factor is a substance that has been claimed to increase immune function. It has never been proven to be beneficial for diseases such as allergies or asthma. Because it is being sold as a 'supplement', it does not need to be proven to cure any disease, unlike medications prescribed by a physician. Research done on transfer factor largely stopped in the early 1990's when it was found not to work with human diseases. The claimed mode of action for transfer factor is to increase immune responses. This is the opposite of what is wanted most often in asthma, where medications are given to suppress allergic inflammation.
The issue is that asthma is a disease that is episodic and can resolve somewhat, so it is difficult, if not impossible, to tell if a treatment or medication really makes a patient better or if they just got better on their own. That is why research, especially large clinical trials, are needed in diseases such as asthma, and why it is important that you work with a health care worker that understands the research and can best fit the medications to your clinical situation.