Fuad El-Hibri, whose biotech company won billions of dollars in government contracts to manufacture a vaccine against anthrax but stumbled in 2021 when, having been hired to produce Covid vaccines, it had to throw out the equivalent of 75 million contaminated doses, died on April 23 at his home in Potomac, Md. He was 64.

His death was announced in a statement by his family. A representative for the family said the cause was pancreatic cancer.

Mr. El-Hibri’s Maryland-based company, Emergent BioSolutions, was an obscure player in the world of government contracting, but an influential one: It deployed extensive lobbying efforts and campaign contributions to secure a near-monopoly on the production of an anthrax vaccine in the early 2000s. The contract accounted for nearly half the budget for the Strategic National Stockpile, a medical reserve held in case of crises like a bioweapons attack or a pandemic.

Though the relationship occasionally drew scrutiny — including an extensive investigation by The New York Times in March 2021 — it also made Mr. El-Hibri’s company a seemingly obvious choice to produce the Covid vaccines developed by Johnson & Johnson and AstraZeneca. Emergent received a $628 million contract from the federal government in 2020.

But in fact, Emergent was not at all ready for that imposing task. Though it was already part of a government program to scale up vaccine production rapidly in an emergency, it had yet to demonstrate such a capacity when it began to churn out Covid vaccines in early 2021.

In March of that year, the company announced that because of worker error, the equivalent of some 15 million doses of the Johnson & Johnson vaccine had been contaminated and had to be discarded. Production nationwide shut down temporarily, creating a political headache for the Biden administration, which had been hoping for a smooth rollout to tamp down vaccine hesitancy.

Congress launched an investigation, and in May Mr. El-Hibri, who was Emergent’s executive chairman, and Robert G. Kramer, the company’s chief executive, testified before the House Select Subcommittee on the Coronavirus.

While both men defended the company and cited the unprecedented challenge their task presented, Mr. El-Hibri was contrite about its failures.

“The cross-contamination incident is unacceptable,” he said, “period.”

About 60 million additional doses were found to be contaminated in June.

Fuad El-Hibri was born on March 2, 1958, in Hildesheim, Germany, the son of Elizabeth (Trunk) El-Hibri, a homemaker, and Ibrahim El-Hibri, an engineer and entrepreneur. He grew up in Lebanon and Germany and graduated from Stanford University in 1980 with a degree in economics. He received a master’s degree in public and private management from the Yale School of Management in 1982.

Mr. El-Hibri began his career with Citicorp in Saudi Arabia and later worked for the consulting firm Booz Allen Hamilton in Indonesia. After returning to the United States, he started a business that helped national telecom companies upgrade their networks in Russia, Venezuela and El Salvador.

In the 1990s, he advised the Saudi Arabian government on its efforts to buy millions of doses of an anthrax vaccine. That experience seeded the idea for what became Emergent BioSolutions.

He co-founded the company, originally called BioPort, in 1998. He and his partners, including William J. Crowe, a former admiral, soon won a bid to buy a disused government laboratory in Lansing, Mich., and upgrade it to produce anthrax vaccines for the U.S. military.

The company changed its name to Emergent BioSolutions in 2004. It went public in 2006.

Though it mostly focused on just one product and one customer (it also produced Narcan, used to treat opioid overdoses), Emergent grew rich under Mr. El-Hibri’s leadership, reporting $1.5 billion in revenue in 2020.

As The Times’s investigation found, the company’s financial success was in part attributable to its aggressive efforts to win a large part of the strategic stockpile’s budget. Many experts consider it an outsize chunk, given the relatively low risk of a widespread anthrax attack and the option to use cheap antibiotics for many cases.

“Purchases are supposed to be based on careful assessments by government officials of how best to save lives,” the investigation found, “but many have also been influenced by Emergent’s bottom line.”

Mr. El-Hibri and his wife were prolific campaign donors; they gave nearly $1 million between 2018 and 2021, mostly to Republican candidates. An employee political action committee at Emergent gave $1.4 million more over the same period.

Those connections proved crucial in the fall of 2020, when Emergent was one of two facilities contracted to produce Covid vaccines. Shortly afterward, Mr. El-Hibri cashed out $42 million in shares and stock options.

After the production debacle at Emergent became public, the company faced an uprising by shareholders, including a lawsuit accusing it of committing securities fraud by falsely claiming it was ready to produce the vaccine in order to boost the value of its stock.

Mr. El-Hibri stepped down as chairman of Emergent BioSolutions on April 1.

He is survived by his wife, Nancy (Grunenwald) El-Hibri; his mother; his brother, Samir; his sister, Yasmin El-Hibri Gibellini; his daughters, Faiza and Yusra El-Hibri; his son, Karim; and three grandchildren.