With peanut allergy treatment on a roll, Aimmune details egg, milk programs

Aimmune has been charging ahead on its peanut allergy treatment, with phase 3 data to read out in the first quarter and plans to submit a BLA at the end of the year. Now, the company is teeing up to expand its platform to other food allergies, namely egg and milk allergies.

The oral immunotherapy company’s approach is two-pronged: The peanut program is designed to protect patients from severe reactions from accidental exposure to peanuts, while its egg and milk program is aimed at reintroducing foods containing those allergens into a patient’s diet.

“We are looking at two different patient populations,” said CEO Stephen Dilly, Ph.D., who is set to retire at the end of the year. “There is the group of allergens you don’t really need to eat, but it’s hard to avoid them.”

He means allergens like peanuts, tree nuts and shellfish—“No one is going to be nutritionally deficient by not eating them,” so avoiding peanuts isn’t the issue, accidentally eating foods with trace amounts of peanuts is. Aimmune’s goal is to relieve the burden on peanut-allergic patients and their families.

The peanut treatment, AR101, sailed through phase 2 in 2016, protecting 100% of patients who ate 443 mg of peanuts, 90% of those who ate 1,043 mg and 60% who ate 2,043 mg. A single peanut weighs in at about 300 mg, the company says, while the average accidental exposure tends to hover around half a peanut.

The biotech is partnering with Sanofi and Regeneron on an exploratory phase 2 study combining AR101 with the latter companies’ dupilumab, approved for the treatment of atopic dermatitis. The hope is to achieve the next level of treatment: Currently, patients who stop the treatment lose desensitization.

The primary endpoint of the study includes tolerating doses of peanut protein in a food challenge that will include doses matching and exceeding those being tested in current AR101 trials. The companies will also look into achieving sustained unresponsiveness, in which a patient is still protected even after taking a break from treatment.

As for milk and egg, these “are in an awful lot of stuff that is essential to your nutrition as a child,” Dilly said. So Aimmune is using the same platform, CODIT (characterized oral desensitization immunotherapy), to get to a point at which patients are desensitized enough to eat these foods again. Aimmune’s approach involves giving patients escalating doses of the allergen—starting very small—until it achieves a sufficient level of protection.

“The hardest thing for us to make is the first dose,” Dilly said. “It’s easier to get higher quantities right, but at the really microscopic levels of protein, we need to make sure it’s the right potency, that it’s evenly distributed throughout the diluent and show that it’s stable.”

Challenges in stability can hold up the timeline—you can’t just chuck some egg white powder or milk powder into a dosing form and call it a day. But the good news is, Dilly said, we know what eggs and milk do in people who aren’t allergic to them.

Once the formulation hurdle is cleared, the company can take treatments straight into phase 2 studies and then phase 3 confirmatory trials. While there’s a lot of prework—four year’s worth, in the case of AR101—the actual journey through the clinic can be relatively quick, Dilly said.