GlaxoSmithKline's ($GSK) in-development shingles vaccine successfully staved off the virus in a massive Phase III study--and, in contrast with its top competitor, the shot's effects didn't wane among elderly patients.
The vaccine, HZ/su, reduced the risk of shingles by 97.2% compared with placebo in a study involving more than 16,000 patients, GSK said, maintaining its efficacy across all age groups. That latter point is particularly important, as Merck's ($MRK) Zostavax, the only approved shingles vaccine, tends to lose steam as patients approach 70.
Analysts with eyes on the shingles race have long pointed to elderly efficacy as the key catalyst that could vault HZ/su over Zostavax, and the Phase III success could rocket GSK's candidate to more than $1 billion in annual sales once it's approved. That'll likely come at the expense of Merck, which grossed $765 million from Zostavax last year.