FDA granted market authorization yesterday to Protein Sciences’ Flublok®, marking the third approval in less than two months to a flu vaccine, and the second to a vaccine produced through an alternative to the decades-old methods of growing, then inactivating a flu virus in the eggs of chickens.
Flublok is the first recombinant flu vaccine approved for market. The vaccine consists of three full-length, recombinant flu hemagglutinin (rHA) proteins designed to fight influenza virus A strains, H1N1 and H3N2, and an influenza virus B strain. The trivalent composition of proteins is manufactured using Protein Sciences’ baculovirus expression vector system (BEVS) technology and expresSF+® cell line.
Flublok has three times the amount of active ingredient in traditional flu vaccines, and according to Protein Sciences contains no thimerosal or other preservatives, no antibiotics, and no adjuvants. Being egg-free, Protein Sciences’ technology cuts by several weeks the time needed for producing large quantities of the vaccine in the event of a pandemic. The vaccine will be widely available for the 2013–14 flu season, though limited quantities of Flublok—some 150,000 doses, company president & CEO Manon Cox told The New York Times—will be available for the current season.
In contrast, the two other recently approved vaccines won’t reach the market until next flu season. In November, FDA approved Novartis’ Flucelvax®, which also allows for quicker production as the first cell-culture-derived vaccine using mammalian cells rather than chicken eggs. Flucelvax was approved for adults ages 18 and older. And last month, FDA authorized for market egg-based GlaxoSmithKline’s Fluarix® Quadrivalent for adults and children three years and older, as the first intramuscular vaccine designed to fight four influenza strains—two A strains, two B strains.
FDA approved 10 new flu vaccines during 2012; Flublok is the first to be approved this year.
Flublok has been approved for adults ages 18 to 49. Protein Sciences said in a statement it expects FDA to approve the flu vaccine for all adults later this year.
In anticipation of FDA approval, Protein Sciences in November said it signed a five-year lease with five-year renewal option for two buildings totaling 83,000 square feet within Pfizer’s Pearl River, NY, campus. The space will be used for housing a production line for Flublok, with initial plans for 50 full-time jobs, potentially growing to 150 jobs over the next decade. Based on those plans, Protein Sciences received $2 million in tax credits from New York state’s economic development agency, Empire State Development.
The company, based in Meriden, CT, said at the time it was also working with Connecticut officials “to explore opportunities to expand the company's manufacturing operations near its headquarters.”
According to FDA, the technology used for producing Flublok is new to flu vaccine production, but has been incorporated in the making of vaccines approved by the agency for other infectious diseases.
Flublok and a sister vaccine designed to protect against pandemic influenza, Panblok®, were developed by Protein Sciences with the U.S. Biomedical Advanced Research and Development Authority (BARDA) through Contract No. HHS0100200900106C, awarded in 2009. According to the company’s website, the contract has a budget of approximately $147 million over five years, with the first 18-month “base” period budgeted at $34.5 million. In May 2011, BARDA extended Protein Sciences’ contract for an additional two years, with a budget of about $47 million: “This ensures that Flublok and Panblok development is secured at least through mid-2013.”
The two-year period ends later this year. When that occurs, some $66 million will remain for a second option period, the company stated. Early clinical development of Flublok and Panblok was also funded by grants from NIH through its Vaccine Treatment and Evaluation Units.