A novel amphetamine sulfate improved symptoms in adults with attention-deficit-hyperactivity disorder (ADHD), according to a phase III study.
In the randomized, double-blind study, adults given 20 mg of the investigational AR19 saw a significant improvement in total score on the Adult ADHD Investigator Symptom Rating Scale (AISRS) compared with placebo after 5 weeks (least squares mean treatment difference -7.2, 97.5% CI -11.3 to -3.1, P<0.001), reported Ann Childress, MD, of the Center for Psychiatry and Behavioral Medicine in Las Vegas, and colleagues.
A 40-mg dose of AR19 also significantly improved total AISRS score compared with placebo (-7.3, 97.5% CI -11.4 to -3.2, P<0.001), they stated in a presentation at the virtual Psych Congress.
Both treatment doses showed significantly improvement in symptoms versus placebo starting at week 1:
- AR19 20 mg: mean treatment difference -5.3 (97.5% CI -8.7 to -1.8)
- AR19 40 mg: mean treatment difference -5.2 (97.5% CI -8.7 to -1.8)
And by week 5, both doses showed significant improvement versus placebo for AISRS subscale scores for hyperactivity/impulsivity and inattentiveness.
AR19 is an immediate-release amphetamine sulfate, formulated as pellets-in-capsule, that is designed with physical and chemical barriers to deter misuse or abuse by snorting, smoking, or IV injection.
Arbor Pharmaceuticals' for AR19 was accepted by the FDA in May 2020, and has a Prescription Drug User Fee Act (PDUFA) target action date of Nov. 15, 2020.
The study findings didn't come as a surprise, co-author Stephen Faraone, PhD, of SUNY Upstate Medical University in Syracuse, New York, explained to 51˶.
"AR19 contains the same active ingredient as [Arbor Pharmaceuticals'] currently-approved ADHD treatment Evekeo [amphetamine sulfate], and clinical trials have demonstrated its bioequivalence to Evekeo," he pointed out. He added that the authors expected AR19 would achieve the same therapeutic benefit as tablet-formulated Evekeo in patients with ADHD.
But "What differentiates AR19 are its barriers to manipulation for non-oral use, which may provide an important benefit for reducing the dangerous risks associated with snorting, smoking, and injecting prescription stimulants," Faraone stated. "Nonmedical prescription stimulant abuse and misuse occurs across the United States, and can cause serious adverse outcomes especially when used non-orally."
"In 2018, an estimated 5.1 million people [ages ≥12 years] reported that they had nonmedically used prescription stimulants in the past year," he added.
And because prescription stimulants are for ADHD, many patients rely on immediate-release stimulants in order to manage day-to-day symptoms.
"If approved, AR19 would be the first-ever immediate-release option that reduces the risk of being misused or abused by snorting, smoking or injecting, making it an important advance and potentially part of a comprehensive harm-reduction strategy," said Faraone, who is program director of .
The study included 320 adults, ages 18 to 55, who had received a primary ADHD diagnosis according to DSM-5 criteria. All participants had an AISRS total score of at least 26 at baseline along with a Clinical Global Impression, Severity (CGI-S) score of at least 4.
During the trial, the participants were dosed once in the morning and then again about 4 to 6 hours after, for a period of 5 weeks.
A few treatment emergent adverse events (AEs) were considered frequent, occurring in 5% or more of either treatment group, and included insomnia, dry mouth, headache, and decreased appetite. Other AEs associated with the treatment included hyperhidrosis, nasopharyngitis, heart palpitations, and tachycardia.
Disclosures
The study was funded by Arbor Pharmaceuticals. A co-author is a company employee.
Childress disclosed support from, and/or relevant relationships with, Allergan, Shire/Takeda, Emalex, Akili, Arbor Pharmaceuticals, Ironshore, Aevi Genomic Medicine, Neos Therapeutics, Otsuka, Pfizer, Purdue, Rhodes, Sunovion, Tris, KemPharm, Supernus, the FDA, and Cingulate.
Faraone disclosed support from, and/or relevant relationships with, Takeda, OnDosis, Tris, Otsuka, Arbor, Ironshore, Rhodes, Akili Interactive Labs, Enzymotec, Sunovion, Supernus and Genomind, Guilford Press, Oxford University Press, and Elsevier, as well as being a patent co-holder for the use of sodium-hydrogen exchange inhibitors in the treatment of ADHD.
A co-author disclosed support from, and/or relevant relationships with, the National Football League, Tris Pharma, Shire/Takeda, St. Martin's Press, Routledge/Taylor & Francis Group, and Arbor Pharmaceuticals.
Primary Source
Psych Congress
Childress A, et al "A randomized, placebo-controlled trial to evaluate the efficacy and safety of AR19 (amphetamine sulfate) in adults with attention-deficit/hyperactivity disorder" Psych Congress 2020; Poster 105.