ATTRACT-ive results

The investigational product in the ATTRACT study is C21.  C21 is a first-in-class, orally available, low molecular weight, angiotensin II type 2 receptor (AT2R) agonist that activates the “protective arm” of the renin-angiotensin system (RAS) leading to resolution and regeneration following tissue damage. The compound is currently in a phase 2 proof-of-concept trial in IPF, and in a pivotal phase 3 trial in Covid-19.

Professor Porter has been working with Vicore Pharma on C21 for over 7 years and is the Principal Investigator of a study of C21 in COVID-19 (ATTRACT) and a separate study of C21 in IPF (AIR).

The results of the ATTRACT trial were recently published in EClinicalMedicine, a peer reviewed clinical journal published by The Lancet, and are available

This randomized, double-blind, placebo-controlled trial showed that C21 on top of standard of care significantly reduced the need for oxygen indicating faster patient recovery compared to placebo.

Following that study, Vicore announced positive results from the ATTRACT phase 2 extension study of AT2R agonist C21 in hospitalized Covid-19 patients in November 2021.  The new results are based on high-resolution computerized tomography (HRCT) scans from a 3–6-month follow-up trial of 33 patients with Covid-19 participating in Vicore’s phase 2 ATTRACT trial. The C21-treated patients (n=17) displayed reduced pathological abnormalities compared to the placebo-treated group (n=16); in the C21 group, on average 10.3% of the lung was affected compared to 19.2% in the placebo group. The dominating radiological change was ground glass opacity, a pathological characteristic following viral respiratory infection.

There is now a phase 3 ATTRACT-3 trial design, approved by the FDA in June 2021, and is currently recruiting patients in US, Czech Republic, Ukraine, India, South Africa, and the Philippines. ATTRACT-3 is a randomized, double-blind, placebo-controlled, global, phase 3 trial which will include 600 adult patients hospitalized with Covid-19 requiring oxygen support but not mechanical ventilation.  The primary objective is to evaluate the effect of C21 on recovery from Covid-19.

ATTRACT-3 is expected to deliver top-line data in 2022.


[Posted 11.11.21]

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