GSK and Medicago report positive Phase 3 results for plant-based COVID-19 vaccine

Pharmaceutical companies GSK plc and Medicago announced on December 7, 2021, positive efficacy and safety results from a global Phase 3 study of Medicago's plant-based COVID-19 vaccine candidate, developed in combination with GSK's pandemic adjuvant.

The study, which involved over 24,000 participants across six countries, demonstrated overall vaccine efficacy of 71% against all circulating SARS-CoV-2 variants. The efficacy against the Delta variant was 75.3%. The trial was conducted in an environment dominated by virus variants, unlike many previous Phase 3 trials for other COVID-19 vaccines.

The vaccine candidate was well-tolerated, with no related serious adverse events reported among participants who received the vaccine. Symptoms were generally mild to moderate and transient. Full results from the study are expected to be published in a peer-reviewed journal.

Medicago plans to submit an application for regulatory approval to Health Canada shortly. The company has also initiated discussions with regulatory authorities in the United States and the United Kingdom, as well as with the World Health Organization (WHO). GSK highlighted the potential of the plant-based technology combined with its adjuvant as a potentially refrigerator-stable option.