Johnson & Johnson Begins Two-Dose Phase 3 Trial Of COVID-19 Vaccine

Johnson & Johnson JNJ has started the two-dose Phase 3 trial of its experimental COVID-19 vaccine, dubbed "ENSEMBLE 2," the pharmaceutical company announced Sunday.

What Happened: Johnson & Johnson aims to administer its experimental COVID-19 vaccine to 30,000 volunteers globally as part of the trial, through its subsidiary Janssen.

The company said the two-dose late-stage trial will run in parallel to "ENSEMBLE," the single-dose regimen trial it had announced in September. Johnson & Johnson said it continues to enroll volunteers in the first study and is on track to meet its target of 60,000 participants worldwide.

Reuters reported earlier in the day that the New Jersey-based pharmaceutical giant is enrolling 6,000 volunteers at 17 sites in the United Kingdom for the two-dose Phase 3 trial.

Volunteers will be given the first dose of the experimental vaccine called Ad26COV2, or a placebo, followed by the second dose or the placebo 57 days later, as per the newswire. Ad26COV2 uses an adenovirus vector to transport the immunizing protein into the body. 

Why It Matters: The Phase 3 trial is the final step before drugmakers approach the regulators for approval.

Positive results from the single-shot trial will simplify the distribution of millions of doses compared to leading rivals requiring two doses. The double-dose trial's efficacy will be affected if the participant fails to return to get the second shot.

It is the third experimental COVID-19 vaccine to enter Phase 3 trials in the U.K., followed by Novavax, Inc NVAX, and AstraZeneca plc AZN. 

"All the vaccines that are being [trialed] work by generating immune responses to the same part of the coronavirus as the RNA vaccine that has announced some interim early results," Saul Faust, J&J's chief investigator said on the U.K. trial, as per the Financial Times. 

Faust also said that it is important to pursue trials of many different vaccines from many different manufacturers to ensure global supply.

The two-dose trial will last for 12 months and complete the recruitment of participants by March 2021.

Price Action: J&J shares closed 1.08% higher at $149.90 on Friday.