Breakthrough Clinical Trials For Peanut Allergies

Peanut allergies are common. An estimated 2% of children¹ in the US have a peanut allergy.

In this context, an allergy means a potentially life-threatening reaction to peanuts. In contrast, a food intolerance causes discomfort, such as indigestion.

In extreme cases, a person with a peanut allergy doesn’t even need to eat peanuts to trigger an allergic reaction. Just being in a room with peanuts can lead to anaphylaxis — a severe reaction involving difficulty breathing, swelling of the face and tongue, narrowing of the airways, vomiting, fainting, and hives. Anaphylactic shock requires urgent medical attention, typically a life-saving epinephrine shot.

The Centers for Disease Control & Prevention (CDC) report that between 1997 and 2011, food allergies in US children increased by 50%². From 1997 to 2008, peanut allergies in children tripled.

With peanut allergies increasingly affecting so many children, scientists are developing treatments and working to understand more about food allergies. Fortunately, researchers are making significant headway with clinical trials.

What is a peanut allergy?

Peanuts are one of eight major food allergens³ identified by the Food Allergen Labeling and Consumer Protection Act.

If you have a peanut allergy, being exposed to peanuts causes your immune system to launch a strong immune response and attack the allergen — in this case, the protein in peanuts.

An allergic reaction could be mild — like getting a couple of hives, or your mouth is mildly itchy. But, in extreme cases, the immune overreaction triggers anaphylaxis — which may involve the throat swelling and closing, along with trouble breathing and other life-threatening symptoms that require swift medical attention.

How common is anaphylaxis death from peanuts?

Though hospital visits for food-allergy-related anaphylaxis are on the rise, death from food allergies is uncommon (an estimated 1.8 fatalities per million per year among people with food allergies). Still, a meta-analysis⁴ found that peanuts caused 62% of all food anaphylaxis deaths.

A peanut allergy is the most common food allergy in US children and the second most common in adults. One study⁵ found that the first allergic reaction to peanuts usually happens at home, when a child is between 14–24 months old. While most food allergies appear during childhood, at least 15% of patients receive their first diagnosis as adults.

If a child accidentally eats peanuts, there is a significant risk of a life-threatening allergic reaction. Accidental exposure with a fatal reaction⁵ happens mainly outside the home. Often, prepared food is to blame due to cross-contamination or mislabelling.

In the US, peanuts are one of the eight allergens with labelling requirements under the Food Allergen Labeling and Consumer Protection Act of 2004⁶. In the European Union (EU), peanuts are one of 14 allergens manufacturers must label according to the EU Food Information for Consumers Regulation (EU FIC)⁷. These laws ensure that peanuts and other allergens are clearly listed as ingredients.

Most children remain peanut-allergic for life. 20% of children outgrow their peanut allergy⁸ and develop clinical tolerance. Approximately 20-25% of epinephrine (EpiPen) injections at schools are given to children whose allergy was previously unknown. More than 15% of school-aged children with food allergies have had a reaction in school.

How does an allergic reaction develop?

When you have an allergic reaction, your immune system mistakes a food ingredient or substance as dangerous.4 If you eat peanut-containing food, your immune system causes cells to release an immunoglobulin E (IgE) antibody to neutralize the ‘harmful’ peanut protein.

When you next eat even the smallest amount of peanuts, IgE recognizes it and signals your immune system to release chemicals into your bloodstream, including one called histamine. These chemicals cause allergy symptoms like itchiness, runny nose, and puffy eyes.

Histamine can have a severe response, resulting in shortness of breath, tongue swelling, lip swelling, and in extreme cases, throat swelling, which is a medical emergency.

Symptoms and risks of peanut allergy

Many allergic reactions are mild to moderate, and they may cause:

• Itchy skin or a rash (hives) 

• An itchy feeling in the mouth or throat

• Swelling of the lips, around the eyes, or face

• Runny nose or sneezing

• Gastrointestinal issues like vomiting, nausea, diarrhea, or abdominal pain

The most problematic symptom of an allergic reaction is anaphylaxis, and peanuts are one of the leading causes. A reaction can happen either minutes or hours after exposure. Typically, symptoms appear within two hours.

Anaphylaxis symptoms⁹ include:

• Swelling of the tongue or throat

• Difficulty speaking or swallowing

• Hoarse voice, persistent cough, wheezing, noisy or difficulty breathing

• Anxiety, lightheadedness, confusion, loss of consciousness

• Fast or slow heart rate, palpitations, low blood pressure

• In babies: paleness, floppiness, or sudden sleepiness

Who is at risk of developing an allergy?

Several risk factors for developing peanut allergies include:

• Family history of asthma or having asthma 

• Egg allergy

• Sesame allergy

• Lupin allergy

• Fenugreek allergy

• Tree nut allergy

• Having eczema

Studies are examining a possible link between geographic location and peanut allergies.

What is peanut allergy oral immunotherapy?

Firstly, peanut allergy oral immunotherapy (OIT) is a treatment, not a cure. However, it reduces the frequency and severity of allergic reactions.

Peanut OIT focuses on building your tolerance to peanuts by desensitizing your body to the allergen. Your treatment starts with a tiny amount of peanut protein, which the allergist, a trained professional, will slowly increase to larger amounts until you consume a ‘target’ dose. Researchers have discovered that gradual peanut exposure can desensitize patients to high quantities of peanut protein.

Only a medical professional should attempt peanut OIT. Never attempt it on your own at home. Your child could develop a severe allergic reaction, requiring immediate treatment. A doctor has the necessary equipment and medicine to treat an allergic reaction instantly.

85% of children achieved peanut allergy remission

A new study¹⁰ by Melbourne’s Murdoch Children’s Research Institute (MCRI)¹¹ reported evidence of amazing breakthroughs in peanut allergies with oral immunotherapy. Researchers started with minuscule doses of peanut protein powder under medical supervision: the first dose was 1% of a peanut. The control group in the study took a probiotic with their oral immunotherapy to reduce any gastrointestinal side effects of the peanuts.

Researchers gradually increased the peanut dose over 18 months, with the final amount being 2,000mg of peanut protein, equal to eight peanuts. After treatment, around half of the children went into remission, and another quarter showed reduced sensitivity. Both the immunotherapy only and immunotherapy and probiotic approaches were successful. However, researchers said that the probiotic wasn’t necessary, but it may offer a safety benefit in younger children.

According to MCRI’s Dr. Paxton Loke, 99% of children who achieved remission and stopped treatment were eating peanuts as often as they liked 12 months after stopping treatment. The children could eat peanuts safely without worrying about an allergic reaction¹², which is an incredible improvement to the quality of life of the children and their families.

A clinical trial desensitized peanut allergy in 71% of children

A clinical trial¹³ funded by the National Institutes of Health (NIH) found that immunotherapy safely desensitized most highly peanut-allergic children 1-3 years old. The treatment also induced remission of peanut allergy in one-fifth.

In this context, remission is being able to eat the equivalent of 1.5 tablespoons of peanut butter, without having an allergic reaction for six months after finishing the therapy. Again, those who were the youngest and began the study with lower levels of peanut-specific antibodies were most likely to achieve remission.

By the end of the treatment, the study desensitized 71% of peanut flour children, compared to only 2% who received the placebo flour. The trial suggests there’s a window of opportunity in early childhood for oral immunotherapy to cause remission of peanut allergy.

Tapping into the potential of oral immunotherapy early in life while the immune system matures might change a child’s immune response to peanuts.

A new FDA-approved peanut allergy treatment

Palforzia¹⁴ is a groundbreaking treatment for peanut allergies in children 4-17 years old. It reduces their sensitivity to peanuts in the same way as the other oral immunotherapy trials: by slowly increasing the peanut dose.

Palforzia is peanut powder in capsules that you mix into your child’s soft food like rice pudding, puree, or yogurt. Treatment has to start in a clinical setting, and supervision lasts for at least 22 weeks, so it’s not simply a case of going to your doctor and taking it home.

In the Phase 3 study for Palforzia, 67% of participants¹⁵ could consume 600mg of peanut protein without causing severe symptoms that prevent an increase in dosage.

 In 2020, Palfozoria became the first and only FDA-approved treatment¹⁶ for peanut allergies in the US.

Preventing peanut allergies

In 2017, the National Institute for Allergy and Infectious Disease (NIAID  issued new peanut allergy guidelines¹⁷. The updated advice uses a risk-based approach for introducing peanuts to prevent an allergy from developing. Before these updated guidelines, parents were often advised not to give young children peanuts.

High-risk If your child is in a high-risk category, the guidelines recommend getting them tested for a peanut allergy. Your allergist may do a skin test or blood test. If the skin test does not reveal a large wheal (bump), they may recommend your child try peanuts for the first time in the office where they have medical supplies for any allergic reaction. However, if the skin test reaction is significant (8mm or larger), it’s not recommended that the allergist feed your child peanuts, as they are likely already allergic. Instead, they might suggest your child avoids peanuts entirely due to the strong possibility of a pre-existing peanut allergy.

Moderate-risk Moderate-risk children have mild to moderate eczema, and they have already started solid foods. These infants do not need an evaluation. They can have food containing peanuts at home starting around six months old. Parents can consult with their doctor if they have questions about moving forward.

Low-risk Parents can introduce low-risk children with no eczema or egg allergy to peanut-containing foods at around six months.

It’s best to work on preventing an allergy from developing by introducing peanuts early, rather than you and your child having to check every food item for allergens for years to come. If your child has any risk factors, or if you have concerns, speak to your doctor for advice on peanut introduction.

What’s the future for those with peanut allergies?

Immediate treatment plays a huge part in anaphylaxis survival.

Carrying an epinephrine pen (injector) can be life-saving.

Scientists are making impressive breakthroughs in their understanding and treatment of peanut allergies. Immunotherapy has just recently become available in the US. However, it desensitizes rather than cures peanut allergies.

Researchers have recently begun clinical trials examining the effectiveness of new drug therapies, hoping to have more lasting results. One drug, dupilumab (brand name Dupixent), is already FDA- approved for treating eczema and asthma and may also work to “re-program”¹⁸ the immune system in those with peanuts allergies. More clinical research is necessary.

Despite the recent advances, having an accurate diagnosis, nutritional counselling, allergy action plans, education, and accessible emergency kits remain the gold standard treatment for peanut allergies.

Sources:

1. Oral immunotherapy induces remission of peanut allergy in some young children | NIH: National Institute of Health

2. Facts & statistics | Fare

3. Food allergies | U.S. Food & Drug Administration

4. Review article: The diagnosis and management of food allergy and food intolerances (2015)

5. Peanut allergy: An overview (2003)

6. Food allergen labeling and consumer protection act of 2004 (FALCPA) | U.S. Food & Drug Administration

7. Regulation (EU) no 1169/2011 of the European parliament and of the council (2011)

8. Natural history of peanut allergy and predictors of resolution in the first 4 years of life: A population-based assessment (2015)

9. Peanut allergy | Allergy UK

10. Probiotic peanut oral immunotherapy versus oral immunotherapy and placebo in children with peanut allergy in Australia (PPOIT-003): a multicentre, randomised, phase 2b trial (2022)

11. Murdoch Children’s Research Institute (MCRI)

12. Researchers discover two treatments that induce peanut allergy remission in children | Murdoch Children’s Research Institute (MCRI)

13. Efficacy and safety of oral immunotherapy in children aged 1–3 years with peanut allergy (the Immune Tolerance Network IMPACT trial): a randomised placebo-controlled study (2022)

14. Palforzia | Europian Medicine Agency

15. AR101 oral immunotherapy for peanut allergy (2018)

16. FDA approves first drug for treatment of peanut allergy for children | U.S. Food & Drug Administration

17. Addendum guidelines for the prevention of peanut allergy in the United States (2016)

18. Can a biologic drug teach the body to forget peanut allergy? | Allergic Living

Victoria is a writer from the UK with a keen interest in health and science. She loves writing about mental health, scientific advancements, and dispelling pseudoscience. When she’s not writing sass-laden articles, she walks her rescue dogs, giggles at anxiety memes, eats chocolate, and absorbs useless knowledge for quiz shows.