Dosing Begins in Phase 2 Trial Testing Batoclimab for Myasthenia Gravis

A Phase 2 clinical trial of Harbour BioMed‘s investigational therapy batoclimab, also known as HBM9161, for myasthenia gravis (MG), has started dosing patients, the company said in a press release.

The trial (NCT04346888) — being conducted at the Huashan Hospital in Shanghai, China — is still recruiting participants for an approximate total of 30. More information is available here.

In autoimmune diseases, including MG, a type of antibody known as immunoglobulin G (IgG) attacks the body’s own cells and tissues. In MG, this impairs the communication between nerve cells and muscles, leading to muscle wasting.

The human neonatal Fc receptor (FcRn) binds to the disease-causing IgG autoantibodies, halting their degradation.

Batoclimab is thought to ease flare-ups in IgG-mediated autoimmune disorders, such as MG, by blocking FcRn and thereby promoting the breakdown of the autoantibodies.

In the Phase 2 trial, patients will be randomly assigned to receive subcutaneous (under-the-skin) doses of batoclimab — at either 340 mg or 680 mg — or a placebo for six weeks. All participants will then receive batoclimab at a dose of 340 mg.

The study will assess the safety, efficacy, pharmacokinetics, and pharmacodynamics of batoclimab. For reference pharmacokinetics refers to the movement of a medicine into, through, and out of the body, while pharmacodynamics is defined as the effects of a compound on the body.

The trial’s main goal is to assess changes in the MG activities of daily living (MGADL) scale, a measure of disease severity, by day 43.

Data from a previous Phase 1 trial (NCT03971916) with healthy volunteers showed that batoclimab was safe and caused a significant decrease in IgG levels.

Harbour is also assessing the therapy’s safety and efficacy in a Phase 2 trial (NCT04428255) in adults with immune thrombocytopenia (ITP), an autoimmune condition characterized by shortage of blood cells called platelets that are required for clotting. The trial, which has also begun dosing patients, is recruiting.

“We are excited to make strides with the enrollment of the patients for both MG and ITP trials. Given our commitment to drive next generation of therapeutics, Batoclimab is expected to bring life changing solutions for large numbers of patients in China,” Jingsong Wang, MD, PhD, founder, chairman, and CEO of Harbour, said in the release.

“The dosing of the first patient in the [Phase 2] trials is only a start, and we will continue to accelerate the development of Batoclimab to treat patients with MG and ITP,” Wang added.

Batoclimab is also being tested as a treatment for Graves’ ophthalmopathy — an autoimmune disorder that affects the eyes — and neuromyelitis optica spectrum disorder (NCT04227470), an inflammatory disease of the brain and spinal cord.