Helus Pharma reports positive Phase 2 results for HLP004 in treatment-resistant generalized anxiety disorder, showing significant anxiety reduction and durable response rates when added to standard antidepressant therapy.
Written By: Sana Khan, BPharm
Reviewed By: Pharmacally Editorial Team
Helus Pharma has reported positive topline results from a Phase 2 signal detection study evaluating HLP004 as a potential adjunctive treatment for adults with moderate-to-severe generalized anxiety disorder (GAD) who remain symptomatic despite ongoing standard-of-care antidepressant therapy.
GAD affects more than 20 million adults in the United States, and nearly half of patients do not achieve adequate symptom control with first-line therapies such as selective serotonin reuptake inhibitors and related agents. Currently, no adjunctive pharmacologic therapy has been approved for GAD, and no new monotherapy has been introduced in nearly two decades.
The Phase 2 study (NCT06051721) enrolled 36 patients with moderate-to-severe GAD who continued receiving their existing antidepressant or anxiolytic medications throughout the trial.
Participants were randomized in a 2:1 ratio to receive intramuscular HLP004 or placebo, with patients assigned to either a higher 20 mg dose or a lower 2 mg dose, administered as two injections given three weeks apart.
Patients were followed through 12 weeks with additional observational monitoring extending up to one year. Treatment with the 20 mg dose of HLP004 produced a clinically meaningful improvement in anxiety symptoms, with patients achieving an average reduction of more than 10 points on the Hamilton Anxiety Rating Scale by week six compared with baseline, demonstrating benefits beyond ongoing standard-of-care therapy.
Clinically meaningful responses were also observed in this difficult-to-treat population that had remained symptomatic despite established therapies. At six weeks, approximately 59% of patients receiving the 20 mg dose met criteria for treatment response and 32% achieved remission, while the lower dose 2mg also showed measurable clinical activity.
Longer-term follow-up demonstrated sustained benefits, with the pooled study population showing response rates of about 67% and remission rates approaching 40% at six months.
The treatment experience was relatively short, with acute drug effects lasting about 90 minutes and patients typically ready for discharge within roughly three hours, allowing the therapy to fit within the workflow of interventional psychiatry clinics.
HLP004 was generally well tolerated, and investigators reported no drug-related serious adverse events or suicidality-related safety signals during the study.
HLP004 is an investigational intramuscular deuterated serotonergic agonist designed to activate serotonin pathways associated with neuroplasticity.
The therapy is being developed as an adjunctive treatment option for patients with generalized anxiety disorder who continue to experience symptoms despite currently available pharmacologic therapies.
Helus Pharma plans to continue advancing its serotonergic agonist platform and expects to report data from HLP003, another program targeting major depressive disorder, in the fourth quarter of 2026.
Reference
Helus Pharma Announces Topline Results in Phase 2 Signal Detection Study for HLP004 in Patients with Generalized Anxiety Disorder, March 5, 2026, https://ir.helus.com/investors/news/news-details/2026/Helus-Pharma-Announces-Topline-Results-in-Phase-2-Signal-Detection-Study-for-HLP004-in-Patients-with-Generalized-Anxiety-Disorder/default.aspx
A Study of a N, N-dimethyltryptamine (DMT) Analog (CYB004) in Participants with Generalized Anxiety Disorder (GAD), ClinicalTrials.gov ID NCT06051721, https://clinicaltrials.gov/study/NCT06051721
About Author
Sana Jamil Khan, B.Pharm
She is a pharmacy graduate with a keen interest in clinical research, pharmacovigilance, and medical writing, with a growing focus on publication and scientific content development. In her words, she is passionate about translating complex medical data into clear, evidence-based communication.