Molecular Partners Confirms Retained Activity of Ensovibep on the Positions Mutated in Emerging Omicron Variant of SARS-CoV-2 In Vitro

ZURICH-SCHLIEREN, Switzerland and CONCORD, Mass., Nov. 30, 2021 (GLOBE NEWSWIRE) — Ad hoc announcement pursuant to Art. 53 LR:
Molecular Partners, a clinical-stage biotech company developing a new class of custom-built protein drugs known as DARPin therapeutics, today issued a statement regarding the recently identified SARS-CoV-2 variant, termed Omicron (B.1.1.529)¹. The Omicron strain contains 32 new mutations compared to the wild-type strain originally identified in Wuhan, China. Based on previous studies, ensovibep, a tri-specific antiviral targeting the spike protein of SARS-CoV-2, maintains full potency against the individual positions of relevance to ensovibep that are mutated in the Omicron variant.

“With our ongoing global Phase 2-3 clinical trial (EMPATHY) of ensovibep in ambulatory patients, it is imperative that we continually monitor the efficacy of our antiviral against all existing variants, especially variants of concern. While we are only beginning to understand the impact of the Omicron variant, we are thankful to our collaborators at the CHUV and the NIH for having already assessed the individual mutations of this new variant, providing us with confidence that ensovibep is likely to remain active against this emerging threat,” said Patrick Amstutz, CEO of Molecular Partners.

In partnership with the Centre Hospitalier Universitaire Lausanne (CHUV) and the National Institutes of Health (NIH) and throughout its development, ensovibep has been consistently tested in vitro against all existing and potential variants of concerns. To date, ensovibep has maintained activity in vitro against all variants of concern detected, including the Delta strain². Testing has been initiated in order to confirm the potency of ensovibep against the full Omicron pseudotype virus that comprises all mutations simultaneously.

Tri-specific Cooperative Binding Mechanism, designed to prevent loss of potency:
By the merits of its design, ensovibep contains three individual DARPin domains which are highly neutralizing to SARS-Cov-2. When constructed into a single molecule, ensovibep protects against mutational burden through a process known as cooperative binding. The cooperative binding of all three DARPin domains allows potent binding on the spike protein. Even if one of the three binders loses some binding capacity due to a mutation, it is well backed up by the other binding domains. This unique MoA allows ensovibep to efficiently protect against a multitude of variants.

EMPATHY clinical trial
Ensovibep is currently being evaluated in EMPATHY, a global Phase 2-3 study designed to explore the use of ensovibep for the treatment of COVID-19 in patients who are in the early stages of infection to prevent worsening symptoms and hospitalization. Molecular Partners’ collaboration partner, Novartis, is conducting the clinical trial for ensovibep, with Molecular Partners as a sponsor. The phase 2b portion of EMPATHY enrolled patients across six countries. Topline data for the first 400 patients are expected in early 2022.