“Due to high levels of demand for GSK’s Shingrix vaccine, GSK has implemented order limits and providers have experienced shipping delays. It is anticipated these order limits and shipping delays will continue throughout 2018,” notes the Centers for Disease Control (CDC) on its vaccine shortage website. “In response, GSK has increased the US supply available for 2018 and plans to release doses to all customer types on a consistent and predictable schedule for the rest of 2018. Overall, the supply of Shingrix during 2018 is sufficient to support the vaccination of more patients during 2018 than were vaccinated against shingles during 2017.”

Shingles, also known as herpes zoster, can be contracted by anybody who has already had and recovered from the chicken pox. It usually afflicts older people, and nearly a third of the population is expected to develop shingles at one point or another.

Before Shingrix was approved by the Food and Drug Administration (FDA) for U.S. markets in late October 2017, there was only one alternative shingles vaccine: Merck’s Zostavax. Part of the reason for the massive demand is that the CDC has endorsed Shingrix over Zostavax in older populations—and those populations appear to have received the message.

But the shortfall also underlies a promising business case for GSK. Analysts had already pegged potential Shingrix sales at nearly $2 billion per year at its peak; the current demand could mean that eventual sales are even higher—if Glaxo can keep its manufacturing in line with what the market wants.

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