I-Mab Biopharma is initiating the development of TJM2 (TJ003234) to treat cytokine storm in severe and critically ill patients with coronavirus disease (COVID-19). TJM2 is an I-Mab-discovered neutralizing antibody against human granulocyte-macrophage colony stimulating factor (GM-CSF), an important cytokine that plays a critical role in acute and chronic inflammation.

The development will start following the U.S. FDA acceptance of I-Mab’s IND application, and will commence initially in the U.S. with plans to expand into other hard-hit countries.

Cytokine storm is characterized by surge of high levels of circulating inflammatory cytokines, and is an overreaction of the immune system under the conditions, such as CAR-T therapy [1] and patients infected with SARS-CoV-2. Recent studies show that high levels of GM-CSF, along with a few other cytokines, are critically associated with severe clinical complications in COVID-19 patients.  

The company has successfully completed a Phase I study of TJM2 in the U.S., in which TJM2 exhibited favorable safety, tolerability, PK/PD, and immunogenicity profiles. The results from the planned COVID-19 study will also be used to further evaluate the potential therapeutic role of TJM2 in reducing or preventing cytokine storm and neurotoxicity associated with CAR-T therapy.

According to the WHO, as of March 12, 2020, there were 125,048 confirmed cases and 4,613 deaths of COVID-19 globally.