In the bustling cell and gene therapy field, manufacturing is a major hurdle for drugmakers hoping to bring 10 to 20 new products to market each year in the coming decade. Pfizer has invested big money in production capacity—and it's ready to use it not only for its in-house candidates, but for partners, too.

On Wednesday, Pfizer and gene therapy maker Vivet Therapeutics partnered on a manufacturing deal for a Wilson's disease candidate that will be produced at Pfizer's Chapel Hill, North Carolina plant, the companies said. 

The pact is part of Pfizer's "build-buy-partner" strategy, according to a spokesman, in which Pfizer builds gene therapy muscle by acquiring stakes in promising biotechs and then partners to bring their manufacturing processes in house.

Pfizer acquired a 15% minority stake in Vivet back in May 2019 with an exclusive option to buy the company outright. 

In the past few years, Pfizer has invested around $800 million to expand three facilities in North Carolina—including the Chapel Hill site—in what a spokesman called "arguably the largest investment" in the gene therapy field. The facilities total 300,000 square feet of manufacturing space. 

All that square footage means Pfizer can manufacture multiple gene therapy candidates "in parallel," the spokesman said, and Pfizer has left the door open to bringing on other partners as part of its scheme. 

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Gene therapies are notoriously expensive and difficult to manufacture, but companies have nonetheless made major investments in recent years as global approvals are expected to tick up. 

This month, New Jersey CDMO Catalent dropped $130 million into its cell and gene therapy manufacturing facility in Harmans, Maryland, to broaden its late-stage production capacity. The newest investment will add five late-stage clinical and commercial manufacturing suites to the Harmans site, expected to go online in the first half of 2022, Catalent said. 

Even upstream players, including CDMOs that manufacture the viral vectors used in gene therapies, are making big investments. In June, Maryland's Emergent BioSolutions infused $75 million into its Canton, Massachusetts live viral vaccine facility to produce viral vectors for its growing gene therapy business. 

Merck KGaA made a similar investment back in April when it flushed $110 million into its Carlsbad, California viral vector manufacturing site. 

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With between 10 and 20 new cell and gene therapy candidates likely getting approvals each year through 2025, experts in the field have targeted manufacturing capacity as a key concern for growth. 

"Access to capacity is always a challenge in a growing area, and especially in cell therapy, which is personalized to order," Chuck Calderaro, global head of technical operations for Gilead's Kite unit, said during a Fierce Pharma panel in June. "The challenge for us is to be able to scale that excellence as we begin to globalize our cell therapy treatments."

That month, Kite scored a long-awaited FDA approval for its 117,000-square-foot Amsterdam cell therapy site that will act as a hub for its European Yescarta patients.