Ionis: First-In-Class drug bepirovirsen enters phase 3 clinical trials

Recently, Ionis Pharmaceuticals announced that GlaxoSmithKline has initiated two randomized, double-blind, placebo-controlled phase 3 studies to evaluate the safety and efficacy of bepirovirsen (formerly IONIS-HBVRx) in patients with chronic hepatitis B infection (CHB) sex.

GlaxoSmithKline has taken a step towards its goal of providing a functional cure for hepatitis B patients.

In 2019, GlaxoSmithKline paid Ionis an upfront payment of $25 million to obtain the latter’s license to develop bepirovirsen.

bepirovirsen (formerly IONIS-HBVRx, also known as GSK3228836), is an investigational antisense drug designed to reduce the production of the viral protein HBsAg, which is involved in hepatitis B virus (HBV) infection and replication, in both acute and chronic infections Both exist and are associated with poor prognosis in patients with chronic HBV infection.

Dr. Richard S. Geary, Executive Vice President and Chief Development Officer of Ionis, said: “The Phase 3 initiation of bepirovirsen is an important step towards delivering a novel medicine to HBV patients in need. Previously promising Phase 2b results, including the possibility of a functional cure, provide This is an early indication that bepirovirsen has the potential to provide significant benefits to patients with CHB, a serious chronic health problem.”

In a phase 2b clinical trial, bepirovirsen had undetectable virus levels in almost 30% of participants after 24 weeks of treatment.

Currently, CHB treatment is mainly based on interferon and nucleoside analogues, such as entecavir, tenofovir disoproxil fumarate, and tenofovir alafenamide fumarate.

 Interferon drugs mainly strengthen the immune system, and nucleoside analogs prevent or slow down virus replication. 

However, even when the two are used in combination, only a small proportion of patients have undetectable levels of HBsAg.

Therefore, the current first-line therapy for CHB patients can inhibit viral replication, but cannot clear the virus, and generally has to be taken for life. 

As a potential first-in-class treatment for CHB, bepirovirsen’s unique design can simultaneously reduce the replication of hepatitis B virus and inhibit viral antigens, hoping to stimulate innate immunity and help patients achieve functional cure.

Ionis also received a $15 million milestone payment from GlaxoSmithKline related to the progress of bepirovirsen into Phase 3 clinical studies.