PR93912

SHANGHAI, Jan. 4, 2022 /PRNewswire=KYODO JBN/ --

Joint research results from Biologics of Jemincare and Shanghai Institute of

Materia Medica (SIMM) of Chinese Academy of Sciences (CAS) confirmed that

JMB2002, an anti-SARS-CoV-2 neutralizing antibody (NAb) discovered by Biologics

of Jemincare is still effective against Omicron variant of SARS-CoV-2.

A team of scientists led by Dr. Su-Jun Deng from biologics of Jemincare R&D

Center, and another team of scientists from SIMM of CAS, led by Professor H.

Eric Xu and Dr. Wanchao Yin, not only confirmed the binding and pseudovirus

neutralization activity of JMB2002 against Omicron variant, but also solved the

structures of Omicron spike protein in complex with ACE2 and JMB2002

respectively (Figure 1 and Figure 2). Joint research efforts revealed the

mechanisms of increased infectivity and immune escape of the Omicron variant at

molecular level, and demonstrated the unique binding mechanism of JMB2002

differing from all reported NAbs. Detailed findings of novel features of

Omicron variant and JMB2002 have been published on bioRxiv preprint website

(Reference 1).

The latest research results indicated that JMB2002 had high binding activity to

the Omicron variant and showed potent Omicron pseudovirus neutralization

function (Figure 2A, 2B). It is encouraging considering that most approved and

clinical-stage SARS-CoV-2 neutralizing antibody drugs have lost their

neutralization activity or have shown significantly reduced neutralizing

potency due to multiple mutations of the spike protein in Omicron variant.  

One reason of the enhanced infectivity of Omicron variant is that its spike

protein RBD (Receptor Binding Domain) has higher binding ability to the

SARS-CoV-2 receptor ACE2 than that of wild type. There are immediate needs for

developing specific therapeutic antibodies targeting Omicron variant.

Scientists from Jemincare found that the binding affinity of JMB2002 Fab to the

spike protein of Omicron variant is 4-fold higher than that of WT (Figure 2A).

More importantly, professor H. Eric Xu's group has solved the structure of the

complex of Omicron spike trimer bound to JMB2002 (Figure 2C), the structure

shows JMB2002 binds to the back of RBD, a unique binding epitope with novel

conformation (Figure 2D). It suggests that JMB2002 is a new class of SARS-CoV-2

neutralizing antibody with a binding mechanism different from all reported

NAbs, classifying as class V NAb. The results from pseudovirus neutralization

assay indicate that JMB2002 is a broad-spectrum neutralizing antibody targeting

all WHO VOC except the Delta variant (Reference 1).

JMB2002 has finished phase I clinical trial in China

In June 2021, JMB2002 has finished Phase I clinical trial in healthy donors in

China with excellent safety and desirable PK properties. In March 2021, JMB2002

has been approved for clinical trial in US (IND 154745). At present, Jemincare

produced enough JMB2002 drug substance for further clinical investigation at

2000L bioreactor scale.

About Jemincare Group Co., Ltd.

As one of well-known pharmaceutical companies in China, Jemincare has been

focusing on providing patients with high quality medicines, ranking at the

Top10 in the top 100 Chinese pharma companies for years. Jemincare established

its R&D Center in Shanghai Zhangjiang Science City since year 2018 and has

recruited over 500 scientists. The R&D Center has built up innovative

technology platforms of biologics, small molecules, and novel drug delivery

systems etc. and dedicates to develop innovative therapies for kidney disease,

tumors, cardiovascular and cerebrovascular diseases, respiratory disease,

infection, pediatrics, and pain.

For more information, please visit: www.jemincare.com　

Or contact: PR@jemincare.com

Reference

1.   Structures of the Omicron spike trimer with ACE2 and an anti-Omicron

antibody: mechanisms for the high infectivity, immune evasion and antibody drug

discovery, https://doi.org/10.1101/2021.12.27.474273.

SOURCE: Jemincare

Image Attachments Links:

   Link: http://asianetnews.net/view-attachment?attach-id=412027

   Caption: Figure 1. Structure of complex of SARS-CoV-2 Omicron variant spike protein RBD

bound to ACE2. A. Overall structure and conformation of ACE2-RBD complex. B.

RBD-ACE2 interaction interface. C. The interaction interface of RBD dimer.

   Link: http://asianetnews.net/view-attachment?attach-id=412029

   Caption: Figure 2.  A. Binding of JMB2002 Fab to spike protein of Omicron and WT

respectively. B. Neutralizing bioactivities to WT and Omicron variant by

JMB2002 in pseudovirus neutralization assay. C. The comparison of the complex

of Omicron Spike protein RBD bound to JMB2002 and ACE2. D. Novel binding

epitope to Omicron Spike protein by JMB2002, classified as class V neutralizing

Ab (NAb).