PRC-063 Helps Treat Adults with ADHD

November 5, 2020
Kenny Walter

Kenny Walter is an editor with HCPLive. Prior to joining MJH Life Sciences in 2019, he worked as a digital reporter covering nanotechnology, life sciences, material science and more with R&D Magazine. He graduated with a degree in journalism from Temple University in 2008 and began his career as a local reporter for a chain of weekly newspapers based on the Jersey shore. When not working, he enjoys going to the beach and enjoying the shore in the summer and watching North Carolina Tar Heel basketball in the winter.

Clinicians rated 82% of the patients receiving the study drug and 46% in the placebo group as either much improved or very much improved on the Clinical Global Impression of Improvement scale.

A common issues for patients suffering from attention deficit/hyperactivity disorder (ADHD) is that medication can wane over the course of the day in effectiveness.

A team, led by Ann C. Childress, Center for Psychiatry and Behavioral Medicine, assessed the clinical efficacy, time to onset and duration of efficacy, and safety of PRC-063 compared to placebo in adult ADHD patients.

Adults who suffer from ADHD commonly suffer from inattentiveness, a lack of focus, impulsivity, and excessive physical activity. While methylphenidate is a prescribed drug showing efficacy in managing ADHD, because of rapid absorption and a short half-life, the clinical effects of immediate release methylphenidate last for only about 4 hours.

This makes a multiple daily dose of the immediate release formulation or in combination with an extended-release formulation would be necessary in some patients to treat their symptoms throughout the day.

PRC-063 is an extended-release formulation designed specifically to provide sustained delivery for patients with ADHD who require symptom control throughout the day. The multilayer-release beaded formulation enables the patient to take 1 pill daily in the morning. Each identical PRC-063 bead contains both an immediate-release component that represents about 20% of the total dose and a controlled-release component that represents about 80% of the total dose.

In the randomized, double-blind, parallel-group, placebo-controlled, dose-optimized, phase 3 trial, the investigators examined 288 patients who met the inclusion criteria of Structured Clinical Interview for DSM-5 (SCID-5) diagnosis of any of the 3 subtypes of ADHD, ADHD Rating Scale IV (ADHD-RSIV) score ≥28 at baseline, not receiving or dissatisfied with current ADHD therapy, or treatment-naïve, and able to complete standardized, skill-adjusted math tests.

Of the original 288 patients, 239 individuals entered the double-blind period and 221 completed the full-day ALC visit. The median age of the participants was 31 years old, while 54.7% were female. The majority of patients (83.9%) had combined type ADHD and disease severity based on ADHD-RS-IV total scores at baseline were moderate (37.5%) or severe (62.5%).

Following a 7 week dose optimization period, 113 patients were randomized to placebo and 116 patients were randomized to PRC-063.

Following a half-day ALC visit, eligible patients were randomized to receive either the study drug or a placebo for 1 week. The researchers then evaluated post-dose standardized, skill-adjusted math test total scores during the full-day ALC visit.

They also evaluated prespecified safety endpoints throughout the dose-optimization and double-blind treatment periods.

Each participant kept a daily diary to record detail of their sleep during the washout, dose-optimization, and double-blind treatment periods.

Ultimately, the study drug met the primary endpoint of improved post-dose math test total scores across all timepoints during the ALC (least-squares mean difference [SE], 16.3 [4.39]; P = 0.0003).

The researchers also met their secondary endpoints, including improved post-dose math test total scores compared to placebo at every post-dose time point beginning at 1 hour up to and including 16 hours (P < 0.05). During the full-day ALC, the investigators found the PRC-063 group achieved improved ADHD-RS-IV scores when compared to placebo (-8.5 [1.41]; P <0.0001).

In addition, during the full-day ALC, clinicians rated 82% of the patients receiving the study drug and 46% in the placebo group as either much improved or very much improved on the Clinical Global Impression of Improvement (CGI-I) scale.

They also found 78% of the subjects receiving PRC-063 and 42% receiving the placebo as non-severe.

During the dose-optimization period, headaches, decreased appetite, and clinically defined inability to sleep were treatment-emerge adverse events that occurred most frequently. The TEAEs that occurred in at least 2% of both study arms were headaches, fatigue, and upper respiratory tract infections.

“In this ALC study, PRC-063 was well-tolerated and effective for the treatment of ADHD in adults, with onset of action at 1 hour and duration of effect up to and including 16 hours post-dose,” the authors wrote.

The study, “Randomized, Double-Blind, Placebo-Controlled, Parallel Group, Adult Laboratory Classroom Study to Evaluate the Safety and Efficacy of PRC-063 Compared with Placebo for the Treatment of ADHD,” was published online by NEI.