Moderna said it's moving ahead with an omicron-specific booster shot on Wednesday after its original booster lost some effectiveness at six months. The news prodded Moderna stock higher in late action.
At six months following its authorized booster shot — half the size of its original vaccine series — the number of antibodies capable of blocking the omicron variant had declined more than sixfold from their peak. Moderna emphasized, however, there were still detectable antibodies in all participants.
The news is reassuring, Moderna Chief Executive Stephane Bancel said in a written statement. Further, the company said an array of booster formulas and dosages also led to higher levels of virus-blocking antibodies than the original booster shot.
"Nonetheless, given the long-term threat demonstrated by omicron's immune escape, we are advancing our omicron-specific variant vaccine booster candidate and we are pleased to begin this part of our Phase 2 study," he said.
In after-hours action on the stock market today, Moderna stock jumped 1.5% near 157.30. Shares closed the trading day 1.6% higher at 154.96.
Moderna Stock: Tackling Omicron
The omicron variant is highly contagious, leading biotech companies to rethink their booster strategies.
Six months after receiving the authorized booster, participants in Moderna's study showed a 6.3-fold decline in antibodies capable of handling omicron. That's a faster decline than the number of antibodies capable of taking on an earlier iteration. Those virus blockers fell by 2.3-fold over the same period.
Moderna also tested a third dose of its original vaccine and two multivalent candidates also at the same dosage level. Multivalent shots combine vaccines to target multiple strains. In all cases, the boosters led to higher levels of virus-blocking antibodies than the authorized booster shot.
Meanwhile, Moderna says it will test its omicron-specific booster in people who have only received the two-dose primary series, as well as a fourth shot in already boosted individuals. Moderna expects to enroll up to 600 participants in this study.
It's also considering whether to add the omicron booster to its multivalent shots.
Moderna stock remains under pressure, however. Shares have mostly trended down since late November.
Follow Allison Gatlin on Twitter at @IBD_AGatlin.
