Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started
My Medicine

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Allergies Health Center

Font Size

Allergy Vaccine: 6-Shot Cure?

Study Shows Just 6 Weekly Vaccinations Gave Relief From Ragweed Allergy
WebMD Health News
Reviewed by Louise Chang, MD

Oct. 4, 2006 -- Allergy sufferers got at least two ragweed seasons of relief after only six weekly shots of an experimental vaccine.

The finding comes from a small clinical trial conducted at Johns Hopkins University. The trial tested a new kind of allergy vaccine in 25 people with ragweed allergy -- also known as fall hay fever.

The proof-of-concept study was too small to prove anything. But the results so far have study leader Peter S. Creticos, MD, brimming with enthusiasm.

"For many of these people, we have wiped out the disease of ragweed allergy; it is a cure, but we don't know how long that cure will last," Creticos tells WebMD. "These people will throw away their allergy medicines during August, September, and October when hay fever is driven by ragweed. And if this works for ragweed, there is no reason why it can't work for other allergiesallergies."

Creticos is medical director of the Johns Hopkins Asthma and Allergy Center. He has in the past received consulting fees and grant support from Dynavax Technologies, the vaccine manufacturer. However, the current study was sponsored by the Immune Tolerance Network, which is funded by the National Institutes of Health.

The study appears in the Oct. 5 issue of The New England Journal of Medicine.

Vaccine Turns Allergy Off

When the body encounters a harmless foreign substance, it is supposed to get rid of it with appropriate, protective immune responses. Allergies happen when a substance -- an allergen -- sets off an allergic reaction instead of a protective immune response.

If that were the end of it, allergy wouldn't be such a big deal. But for many sufferers, the allergic process becomes a persistent, whole-body immune response that results in swelling, itching, sneezing, dripping, and/or wheezingwheezing.

The experimental allergy vaccine takes advantage of a trick scientists learned from bacteria. Bacteria carry a specific DNA segment that triggers a specific kind of immune response in humans. This immune response shuts down allergy-type immune responses and triggers protective immune responses.

The Dynavax vaccine links a ragweed particle to this bacterial DNA sequence. It's supposed to make the immune system of a person with ragweed allergy act just like the immune system of a person without ragweed allergy, says David Broide, MD, of the University of California, San Diego. Broide, one of the study investigators, is a senior advisor to the Immune Tolerance Network.

"When this vaccine is injected into a patient, the immune system sees the ragweed component not as ragweed allergen but as bacteria," Broide tells WebMD. "It calls up the protective immune response instead of the allergic response. So the immune response is being fooled into making the correct response."

Today on WebMD

man blowing nose
Make these tweaks to your diet, home, and lifestyle.
Allergy capsule
Breathe easier with these products.
cat on couch
Live in harmony with your cat or dog.
Woman sneezing with tissue in meadow
Which ones affect you?

blowing nose
woman with sore throat
lone star tick
Woman blowing nose

Send yourself a link to download the app.

Loading ...

Please wait...

This feature is temporarily unavailable. Please try again later.


Now check your email account on your mobile phone to download your new app.

cat lying on shelf
Allergy prick test
Man sneezing into tissue
Woman holding feather duster up to face, twitching