The Food and Drug Administration on Jan. 31, 2020 approved Palforzia, Aimmune Therapeutics’ oral immunotherapy (OIT) treatment for peanut allergy in children and teens.
This marks the first-ever FDA approval of a therapy for any food allergy, and Dr. Jayson Dallas, Aimmune’s president and CEO, called it “a defining moment for the peanut allergy community.”
While not a cure, the idea behind the Palforzia treatment is to gradually desensitize patients, so that an allergic child would no longer risk a potentially life-threatening reaction to a small amount of peanut. It is meant for children and teens between the ages of 4 and 17.
Dr. Christina Ciaccio, chief of allergy and immunology at the University of Chicago, called the news “a landmark moment.” It means “we can – for the first time – offer children and teens with peanut allergy a proven medicine that employs an established therapeutic approach,” she said.
Lisa Gable, CEO of FARE (Food Allergy Research and Education) welcomed the drug approval, making reference to the psychological burden on families managing peanut allergy. “The risk of accidental exposure is real, and we, as a community, have long awaited an option beyond avoiding peanuts alone,” she said.
Advocate Stacey Sturner expressed excitement that Palforzia’s approval marks the beginning to regulated treatments for food allergies, with the prospect of others on the horizon. “More and more families will be presented with a choice beyond food avoidance, representing a tremendous paradigm shift,” said Sturner, founder the Facebook group Food Allergy Treatment Talk, where parents discuss therapy options.
Aimmune announced that the annual price for the therapy will be set at $10,680 (or $890 a month), about the middle of a range it had previously suggested. The company says it will offer a co-pay program to families who, in consultation with their doctor, want to pursue the treatment. There will also be a no-cost patient assistance program for those who qualify.
With the FDA’s green light, Aimmune plans to begin seminars to train allergists across the U.S. on how to administer the treatment.
Chicago allergist Dr. Aaron Donnell told Allergic Living he is among those interested in offering the Palforzia protocol to patients, though it will require considerably more resources in terms of space and physician time.
Palforzia at the Allergist Clinic
While some U.S. allergists are already conducting what’s called “private practice OIT” simply with regular peanut flour, a majority of allergists have been waiting for an FDA-approved treatment that’s backed by full clinical trials.
“The common refrain among physicians, patients and parents has been, “OIT isn’t FDA-approved,” says Sturner. She predicts the market availability of Palforzia will “significantly increase nationwide access – and relatively quickly.” She hopes that the entry of Palforzia will lead to consistent insurance billing codes, “which are currently frustratingly lacking.”
Aimmune notes that approval of Palforzia’s biologics license application was based on efficacy and safety data from seven clinical studies, including the key Phase 3 Palisade and Ramses clinical trials.
Allergist Donnell says: “What’s nice about Palforzia is it comes with a lot of research and rigorous statistics that I can use to tell families, ‘based on this research, around 80% of kids [after treatment] will be able to accidentally eat a peanut'” without reacting. He says the studies also provide data to share with families on adverse reactions – with the risk of severe anaphylaxis low, but the risk of some reaction symptoms quite high.
Palforzia capsules contain peanut powder with a consistent, calibrated level of allergenic proteins. The amount of protein powder in a capsule starts out minuscule, at 1/2 a milligram. This gradually increases until the patient reaches a daily maintenance dose amount of 300 mg, which is roughly one peanut. To take a dose, the contents of the capsule (or sachet for a higher dose) is mixed into food.
Aimmune is also investigating similar protocols for egg and for tree nut allergies.
Donnell adds that not every patient with peanut allergy will be a candidate suited to Palforzia’s protocol. But is he hearing from many families interested in the treatment? “Oh goodness, yes,” he says.
While it’s not his plan, Donnell says if he opened a full-fledged OIT clinic, he’d have a few hundred patients sign up right away.
Strict Risk Management Plan
An expert panel reviewed Palforizia in September 2019 – weighing efficacy and safety – and recommended approval to the FDA. But as anaphylaxis is a risk with the treatment, the nine-member panel did so with a caveat. Approval would require a risk management and mitigation strategy (REMS for short) for participating allergists to follow.
In its announcement, Aimmune said that allergists and patients have to be enrolled in the REMS plan before the start of the therapy, patients must continue to carry epinephrine and the first Palforzia dose and each up-dosing level will have to be administered at a certified facility equipped to treat anaphylaxis.
Since Palforzia is not a cure as such, the expert panel also discussed that patients and caregivers would need to be counseled against freely eating peanut products once on a maintenance dose.
The FDA is also considering a rival contender for child peanut allergy treatment this year. An expert committee will review DBV Technologies’ Viaskin Peanut skin patch by August 2020, then recommend to the FDA whether to approve.
Safety Considerations
At the September 2019 hearing on Palforzia, the FDA panel asked many questions about safety. Epinephrine was used by 10% in the treatment group, compared to 5% in the placebo group (due to accidental exposures). As well, 11% of the study’s patients dropped out because of allergic reactions.
Aimmune’s chief medical officer, Dr. Daniel Adelman, explained to the panel that most reactions were mild or moderate. He said: “Severe events occurred in 10 patients out of more than 1,000 patients exposed.” He added that “the incidence of adverse reactions declined from updosing to maintenance, and continued to decrease with prolonged dosing.”
The pivotal Palisade study of this biologic drug was published in the New England Journal of Medicine in November 2018. The study showed strong desensitization results with Palforzia, then known as AR101, among 496 patients with peanut allergy. At the end of a three-phase trial, a majority (67%) of patients aged 4 to 17 could consume two peanuts’ worth (600 milligrams) of AR101 without reaction. This compared to 4% of allergic patients in a control group taking a placebo.
Lead investigator Dr. Stacie Jones noted: “The difference between these groups was 63.2%, which was highly statistically significant.”
As well in the Palisade study, over 96% of patients on treatment could tolerate 300 mg at trial completion, and half of treated patients could tolerate 1,000 mg dose without reacting.
Related Reading:
Allergists See Palforzia as Start to New Era of Food Allergy Therapies
Panel Backs FDA Approval for Aimmune’s Peanut OIT Drug
Aimmune’s News Release
AAAAI 2019: Expert Shines Light on Novel Therapies Under Study for Food Allergy
Longer Trial Increased Level of Tolerance to AR101 Peanut Therapy
