Moderna eyes 'early summer' start for phase 3 COVID-19 vaccine trial

Moderna is finalizing the protocol for a phase 3 trial of its COVID-19 vaccine with a view to starting the study early in the summer. The establishment of the timeline, which follows FDA clearance to run a phase 2 trial, puts Moderna on track to win approval for its mRNA vaccine mRNA-1273 next year.

Having been the first group to start testing a vaccine against SARS-CoV-2, Moderna is now on the cusp of phase 2. With the FDA having completed its review of the IND, Moderna expects to start the 600-subject phase 2 “shortly.”

The phase 3 is following closely behind. Moderna is currently finalizing the protocol for the pivotal trial. If the phase 2 and other preparations go as planned, Moderna could get the pivotal clinical trial underway early in the summer, setting it up to gather the data it needs to potentially win full FDA approval for the vaccine next year. 

Big tests that scuttle many R&D programs stand between Moderna and an approval for mRNA-1273. If the vaccine clears those tests, it could become Moderna’s first product, and the first mRNA vaccine altogether, to come to market. Other developers of COVID-19 vaccines including BioNTech, CanSino Biologics and the University of Oxford are racing Moderna through the clinic. 

The rapid emergence of mRNA-1273 and the pandemic that is driving its development has led to a shift in focus at Moderna. Fabry disease program mRNA-3630 has become a victim of the “current strategic priorities” at Moderna, with the biotech discontinuing work on a drug designed to boost production of the α-GAL enzyme. The drug was in preclinical development.

Other programs have been disrupted by COVID-19 and measures taken to contain it but remain on Moderna’s list of active assets. For example, Moderna stopped enrollment in phase 1 trials of rare disease drugs mRNA-3704 and mRNA-3927 in light of the risks the virus poses to potential subjects, their caregivers and the integrity of the studies.

The mRNA-3704 trial had run into difficulties well before the coronavirus crisis hit. At the start of the year, Moderna CEO Stéphane Bancel called the failure to enroll a patient in the mRNA-3704 trial the company’s “biggest execution disappointment” of 2019. Moderna finally enrolled a subject in the trial in February, but was yet to dose them at the time COVID-19 brought work to a halt.

With Moderna also yet to dose a patient in the mRNA-3927 study, Bancel and his colleagues plan to use the forced pause to make changes they think may accelerate enrollment once the studies get going again.