Tom Giangiulio had been on the waiting list for a heart transplant for more than two years, getting weaker by the month, and it did not seem that the wait would be over anytime soon. At 6 foot, 2 inches and 220 pounds, he would need a larger-than-average heart, and it had to come from a donor who matched his blood type: O-positive.

In March 2017, physicians at the Hospital of the University of Pennsylvania offered him a way to shorten the wait: He could get a heart from someone who had been infected with hepatitis C.

As expected, Giangiulio, who lives in Waterford Township, Camden County, became infected. But in his case, and in dozens of others reported Wednesday in a new Harvard study, the virus was quickly cleared with powerful drugs.

Transplant surgeons hope that eventually, these early results will pave the way for thousands of additional organ transplants each year, provided that insurers agree to pay for the expensive drugs. The expected source for most of these additional organs is deaths from the opioid epidemic — a silver lining for a grim reality of 21st-century America.

The study, published in the New England Journal of Medicine, illustrated a promising way to cut the cost of drugs that clear hepatitis C, which runs into the tens of thousands of dollars. Penn and other centers start giving the antiviral drugs to patients several days after transplanting organs. But the Harvard physicians did so within hours, before the infection became established.

That meant they could administer the drugs for four weeks instead of the usual 12, cutting costs by two-thirds.

The Harvard team administered the drugs to 36 patients who received lung transplants and eight patients who got new hearts. Most had no signs of the virus within a few days, and all tested negative within two weeks, said lead author Ann E. Woolley, a specialist in infectious diseases in the transplant program at Brigham and Women’s Hospital in Boston.

In addition to clearing the infection, the patients tolerated the transplanted organs just as well as patients in a separate group that received hearts and lungs from donors who were not infected with hepatitis C.

The study authors used an antiviral drug that is effective against all of the half-dozen forms of hepatitis C. At $75,000 for a 12-week course, it is more expensive than other drugs that work against just one type. But its versatility meant that it could be given promptly, without waiting for tests to determine the type of virus. And since it was given for just four weeks, the actual cost was $25,000, Woolley said.

“We just didn’t want there to have to be any additional steps or delays,” she said.

Woolley and her colleagues estimate that the drugs could expand the number of transplantable organs by as much as 25 percent.

The results are promising, though patients should be followed over the long term to ensure that they fare just as well as other transplant patients, said Penn physician Emily A. Blumberg, who was not involved in the Harvard study but wrote an accompanying editorial.

“Should this be proven to be consistently effective, that would be enormous,” she said.

If anything, physicians say it is possible that organs from infected donors might last even longer than average, as they typically come from people who die young of drug overdoses.

In a couple of cases at other hospitals, patients who received organs from infected donors have cleared the virus but then relapsed, said Blumberg, director of transplant infectious diseases at the Hospital of the University of Pennsylvania. But such patients can then be re-treated with the antiviral drugs.

Elsewhere, physicians have waited several days after transplant before starting a 12-week course of drugs, in part because some patients are not immediately able to swallow the oral medication. The waiting period also may stem from a reluctance to add yet another medication to the patient’s regimen if not absolutely necessary. But nearly all people who receive organs from hepatitis C-infected donors end up testing positive for the virus.

Giangiulio was the first of 10 heart-transplant patients enrolled in a study of antiviral drugs at Penn.

When physicians presented him with the option of a heart from an infected donor, he consulted Cooper University Health Care cardiologist John A. Andriulli. The physician, who is a family friend, worried that Giangiulio’s health had continued to decline while he waited for a large organ from an O-positive donor. (People with blood type O can donate organs to those with other blood types, and thus are called “universal donors,” but they can receive organs only from type O donors.)

“He said ‘Without sugarcoating it, I’m really having my doubts as to whether you’ll make it’ ” without an expedited transplant, recalled Giangiulio, an excavation contractor who was 58 at the time.

Though he would be Penn’s first heart-transplant patient to get the antiviral drugs, Giangiulio was encouraged to hear that Penn and other centers had successfully used them in patients who received kidneys from infected donors.

All went well. Three days after the surgery in June 2017, Giangiulio started a 12-week course of the drug Zepatier, made by Merck, and by the eighth day there were no signs of the virus, he said.

Months later, after recovery, he wanted to thank the family of the young man whose heart was now beating in his chest. He spent five hours drafting a heartfelt letter to the family of a man whose name he did not know.

“Another human being had to die for me to live,” he said. “That’s a hard thing to think about.”

Such communications are passed along via hospital social workers, if the donor’s relatives are willing. In this case, they were. Giangiulio said he exchanged letters with the donor’s parents and finally met them in person last December, a year and a half after he received their son’s heart, and they welcomed him with an emotional embrace.