The flu vaccines are coming: GSK, Sanofi ship the first of more than 150M doses headed to U.S.

Sanofi and GSK announced the first flu vaccine shipments for the 2017-2018 season.

It's the heat of the summer, when few are thinking about the coming influenza threat. But top vaccine manufacturers GlaxoSmithKline and Sanofi have already kicked off their flu shot shipments, and Seqiris is close behind.

Sanofi and GSK each announced they’re beginning shipments for the 2017-2018 flu season, expecting to dispatch up to 70 million and 40 million doses respectively. The news comes shortly after AstraZeneca's FluMist failed to win over a key CDC committee, which recommended against the nasal vaccine for the upcoming season.

In its shipping announcement, Sanofi said it's taking that decision into account in its production plans, aiming to help compensate for the lack of the nasal vaccine. Widespread shipments start next month, the company said.

RELATED: Sanofi gets a flu vaccines booster with $650M-plus Protein Sciences buy

The initial shipments follow Sanofi’s recent move to purchase Protein Sciences for $650 million or more, a deal that brings the world’s top flu vaccine player another quadrivalent vaccine option. Unlike most flu vaccines, which are made with eggs, the Protein Sciences product is made from insect cells. Seqirus also offers cell-based seasonal flu shots.

The news comes as AstraZeneca is expected to lose out on another season of FluMist sales in the key U.S. market. Worried about FluMist's efficacy, the CDC’s Advisory Committee on Immunization Practices last month recommended against its use for the upcoming season. An AZ spokesperson said new data will be available in October, and the panel could change its recommendation if those findings are positive.

After the agency’s recommendation against the vaccine for the 2016-2017 flu season, FluMist sales fell to $104 million worldwide last year, down from $290 million the prior year.

RELATED: AstraZeneca's struggling FluMist loses out on crucial CDC vaccine backing—again

Another top flu vaccine manufacturer, CSL’s Seqirus, hasn’t announced its first shipments, but a spokesperson told FiercePharma the company plans to ship more than 50 million doses during the upcoming season. Seqirus will ship both cell- and egg-based vaccines, he said, as well as trivalent and quadrivalent options.

Sanofi currently holds the top position in the flu vaccine market, with €1.5 billion ($1.73 billion) in sales around the world last year. GSK sold £414 million ($540 million) worth of quadrivalent flu shots over the same period.

After picking up Novartis’ flu vaccine offerings, Australia’s CSL formed flu vaccine unit Seqirus, currently the second-largest flu vaccine player. In CSL’s most recent annual report for the year ended June 2016, the company disclosed that Seqirus generated $652 million in 11 months of sales.