Barinthus Bio Completes Enrollment for Phase 2b Trial in Chronic Hepatitis B & Phase 1 Trial in Prostate Cancer

Barinthus Biotherapeutics plc recently announced the completion of enrollment for two clinical trials: HBV003, a Phase 2b clinical trial of VTP-300 in adults with chronic hepatitis B (CHB); and PCA001, a Phase 1 clinical trial of VTP-850 in men with rising prostate-specific antigen (PSA) after definitive local therapy for prostate cancer (ie, biochemical recurrence).

“We continue to execute our strategy and are pleased to complete the enrollment in two different trials in CHB and prostate cancer, two diseases where recruitment can be a real challenge,” said Bill Enright, Chief Executive Officer of Barinthus Bio. “These two fantastic milestones keep us on track for anticipated data readouts from HBV003 in Q4 of 2024 and from PCA001 in the first half of 2025.”

The Phase 2b HBV003 trial (NCT05343481) has enrolled 121 participants and is designed to obtain critical dosing information for a potential functional cure regimen for CHB, with participants receiving VTP-300 and low-dose (LD) nivolumab. This trial design builds on positive monotherapy results from the clinical study HBV002, which included an evaluation of VTP-300 given alone and in combination with LD nivolumab. Earlier this year, interim data from the HBV003 trial was presented at the European Association for the Study of the Liver (EASL) Congress and demonstrated that treatment with VTP-300 and LD nivolumab is generally well-tolerated and led to a sustained decline in Hepatitis B surface antigen (HBsAg) levels. Participants reaching Day 169 were assessed for NUC therapy discontinuation eligibility in line with the study criteria, with 76% of participants meeting the criteria (n=16/21). 19% of the eligible participants (n=4/21) reached undetectable levels of HBsAg, with 2 of these patients maintaining undetectable levels for over 16 weeks.

The PCA001 Phase 1 trial (NCT05617040) has enrolled 22 participants and is designed to determine the recommended Phase 2 dosing regimen of VTP-850 as well as evaluate safety and efficacy, as measured by PSA and T cell response. VTP-850 is a next-generation prostate cancer immunotherapeutic candidate which utilizes Barinthus Bio’s ChAdOx/MVA platform of two proprietary nonreplicating viral vectors in a sequential dosing approach.

Globally it is estimated that there are approximately 254 million people living with CHB infection. This includes up to 2.4 million in the U.S. and 10.6 million in Europe, with the highest prevalence in East Asia and Africa. Approximately 1.1 million people died from hepatitis B virus infection and related complications in 2022, such as liver cirrhosis and hepatocellular carcinoma. Due to low diagnosis rates, only 13% of people living with CHB are aware of their infection and less than 3% had received antiviral treatment at the end of 2022.

In 2020, prostate cancer was the fourth most common cancer worldwide, with 1.4 million new cases diagnosed. In the US, out of every 100 American men, an estimated 13 will get prostate cancer during their lifetime. In the UK, prostate cancer is the most common cancer in men, with more than 52,000 people diagnosed with the disease on average each year. 20-30% of patients experience rising levels of PSA after local therapy (eg, prostatectomy), indicating that disease was not cured by local therapy. Of men who do experience biochemical recurrence, there is a 1 in 9 chance of developing metastases.

Barinthus Bio is a clinical-stage biopharmaceutical company developing novel immunotherapeutic candidates designed to guide the immune system to overcome chronic infectious diseases and autoimmunity. Helping people living with serious diseases and their families is the guiding principle at the heart of Barinthus Bio. With a focused pipeline built around our proprietary platform technologies, Barinthus Bio is advancing immunotherapeutic product candidates in infectious diseases and autoimmunity, including: VTP-300, that utilizing our ChAdOx/MVA platform designed as a potential component of a functional cure for chronic HBV infection and VTP-1000, utilizing our SNAP-Tolerance Immunotherapy (SNAP-TI) platform and is designed to treat people with celiac disease. Barinthus Bio is also conducting a Phase 1 clinical trial for VTP-850, a second-generation immunotherapeutic candidate designed to treat recurrent prostate cancer. Barinthus Bio’s differentiated technology platforms and therapeutic approach, coupled with deep scientific expertise and focus on clinical development, uniquely positions the company to navigate towards delivering treatments that improve the lives of people with chronic infectious diseases and autoimmunity. For more information, visit www.barinthusbio.com.