iBio, Inc. shared an update on its lead COVID-19 vaccine program, IBIO-202. iBio recently received the U.S. Food and Drug Administration's (FDA) response to its pre-investigational new drug (IND) package for IBIO-202. In light of the feedback received, the Company is moving forward with IND-enabling challenge studies for its second-generation vaccine candidate targeting the nucleocapsid (N) protein and plans to file an IND application before the end of calendar 2022.

Commercially available first-generation vaccines target the frequently mutating spike (S) protein, resulting in waning periods of immunity and the spread of new variants. These developments have prompted the World Health Organization to state that, a vaccination strategy based on repeated booster doses of the original vaccine composition is unlikely to be appropriate or sustainable. Meanwhile, evidence continues to emerge that N-, not S-, reactive T cells appear to play a protective role for SARS-CoV-2 and potentially other betacoronaviruses as well.

The Company previously reported that it had completed extensive preclinical studies and identified an antigen-adjuvant pairing with a favorable Th1 skew. The cytokine response observed with this pairing indicated activation of a primary immune response, differentiation of mature T cells, and reactivation of memory T-cells.