Molecular Partners and Novartis Report Positive Initial Results from Phase 1 Study of its COVID-19 Antiviral Therapy, Ensovibep, in Healthy Volunteers

Zurich-Schlieren, Switzerland, March 09, 2021. Molecular Partners AG (SIX: MOLN), a clinical-stage biotech company that is developing a new class of custom-built protein drugs known as DARPin® therapeutics, and its collaborator Novartis, today announced initial results from its ongoing phase 1 study of its first tri-specific COVID-19 antiviral treatment, ensovibep (MP0420), in healthy volunteers.
In the placebo-controlled phase 1 study, healthy volunteers were randomized 3:1 to receive an infusion of ensovibep, or placebo, respectively. Two dosing cohorts have been fully enrolled and received a single infusion of 3mg or 9mg per kilogram body weight, with 8 patients per dose cohort (16 total: 12 active, 4 placebo). In each of these cohorts, ensovibep was seen to be safe and well tolerated, with no significant adverse events reported. Preliminary results showed extended exposure of the DARPin® candidate in serum, with a half-life of 2-3 weeks, as was expected from preclinical experiments. These data confirm the systemic administration of a multi-specific DARPin® antiviral therapy to be safe and well tolerated, and support advanced plans for additional clinical work in positively diagnosed patients.

“We are excited to see the predictable exposure of ensovibep in this study. These data, coupled with the strong activity demonstrated preclinically against the major variants of SARS-CoV-2 in circulation, make it imperative that we move as quickly as possible to treating patients with our antiviral. These data now show that administration of a DARPin® candidate at these therapeutically relevant dose levels is possible with full consideration of safety and tolerability. We look forward to move rapidly to initiate our phase 2/3 global registration study with our partner Novartis, early in the second quarter of this year,” said Nicolas Leupin, M.D., CMO of Molecular Partners.

Per protocol, a third cohort in this phase 1 study, at a 20mg per kilogram dose level has been planned. As previously disclosed, this cohort has not been enrolled due to the “lock down” enforced in the UK due to the pandemic, starting at the end of 2020. It is possible this cohort can be enrolled in the coming weeks as restrictions lift, but Molecular Partners and Novartis have already identified the therapeutic dose levels which will be investigated in the upcoming clinical studies for infected patients, which are below the 20mg per kilogram dose level.

Media release