COVID-19 Monoclonal Antibody Candidate Post Positive Results for Immunocompromised People

Invivyd, Inc. today announced additional positive initial data from its ongoing Phase 1 healthy volunteer clinical trial of its lead investigational monoclonal antibody (mAb) candidate, VYD222.

The results announced today add to the positive initial Phase 1 data reported by Invivyd in June 2023.

VYD222 is a broadly neutralizing, half-life extended mAb candidate in development for the prevention of symptomatic COVID-19 in vulnerable populations, such as immunocompromised people.

"We are pleased to see a favorable safety and tolerability profile as well as robust serum neutralizing titers against Omicron XBB.1.5 for all the VYD222 dose levels tested in our ongoing Phase 1 clinical trial," said Dave Hering, chief executive officer of Invivyd, in a press release on July 17, 2023.

"We believe these high neutralizing titer values and fold increases at this early timepoint are extremely encouraging as they indicate the potential for VYD222 to protect longer between doses and to provide additional protection from potential loss of neutralization activity as SARS-CoV-2 evolves."

The Phase 1 clinical trial of VYD222 enrolled 30 healthy volunteers across three dosing cohorts. In each cohort, participants were randomized 8:2 to VYD222 or placebo.

The initial Phase 1 data showed that a single administration of VYD222 was generally well-tolerated at all three dose levels tested, with no serious adverse events (SAEs) reported to date. At the middle VYD222 dose tested (2500 mg), geometric mean serum neutralizing titers were 9647.0 (95% CI: 6115.4, 15218.0) against Omicron XBB.1.5 at Day 7, with a geometric mean 92.82-fold rise (95% CI: 21.2, 406.6) from baseline to Day 7.

At the highest VYD222 dose tested (4500 mg), geometric mean serum neutralizing titers were 16864.7 (95% CI: 12825.5, 22176.1) against Omicron XBB.1.5 at Day 7, with a geometric mean 120.97-fold rise (95% CI: 31.4, 466.2) from baseline to Day 7.

The higher VYD222 dose levels tested in the Phase 1 clinical trial are designed to provide additional protection from potential loss of neutralization activity as SARS-CoV-2 evolves.

Analysis of the serum-neutralizing activity from samples collected at different time points across all dose cohorts in Phase 1 clinical trial is ongoing, as is detailed pharmacokinetic analysis and modeling.

Invivyd intends to use these analyses, combined with published clinical outcome data from prior clinical trials of vaccines and mAbs for the prevention of symptomatic COVID-19, including data from its Phase 2/3 clinical trial of adintrevimab for the prevention of COVID-19 (EVADE), to inform its VYD222 dosing strategy further.

Mr. Hering continued, "As a point of reference, we find it encouraging to observe that even our lowest VYD222 dose tested in our Phase 1 clinical trial resulted in higher titers against Omicron XBB.1.5 than the maximum titers against XBB.1.5 from investigational XBB-containing mRNA vaccines tested in humans that were shared at the FDA's recent vaccines advisory committee meeting."

"Higher VYD222 doses tested in our Phase 1 clinical trial have resulted, as expected, in higher titer levels that were well above those reported mRNA COVID-19 vaccine titer levels."

"We believe these initial Phase 1 clinical trial results support the potential for VYD222 to provide safe, meaningful, durable protection for vulnerable populations, such as immunocompromised people who may not generate adequate protection from COVID-19 vaccines, and we look forward to advancing VYD222 as fast as possible in collaboration with global regulators, starting with the FDA."

As of July 2023, mAbs targeting COVID-19 are in use globally.