DALLAS (CBSDFW.COM) – Two days after testing positive for COVID-19, Randy Isenberg of Dallas, said he wasn’t getting any better. “I was achy, very fatigued, very tired.”

So he said his doctor prescribed Eli Lilly’s antibody therapeutic drug.

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Isenberg said hours after getting the infusion, he felt like a new person. “It means that your fever’s gone. The muscle aches, the fatigue.”

He said his symptoms cleared up in a matter of hours. “That’s exactly the way to describe it. This process, clearly, I think is kind of a miracle drug.”

Randy Isenberg recovered from COVID-19 (CBS 11(.

Aside from Eli Lilly, Regeneron developed a similar drug.

The FDA says they’re called monoclonal antibodies and they are directed against the spike protein of the virus and designed to block it from attaching to and entering human cells.

Isenberg says he went from being COVID-19 positive to negative in just seven days.

Dr. Donna Casey, an internal medicine specialist at Southwestern Health Resources, is Isenberg’s doctor. “It is wonderful. I think it’s going to be a game changer.”

A spokesman with the Texas Department of State Health Services said Tuesday, Dec. 15, that during the past five weeks, it has received 24,000 treatment courses, and that the state is receiving more each week.

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The department said demand is exceeding supply and the federal government sends states the therapeutics based on new confirmed COVID-19 cases and hospitalizations.

The CEO of the DFW Hospital Council, Stephen Love said Tuesday that so far, the drugs haven’t made a significant difference during the surge of COVID-19 hospitalizations, keeping just one of 20 infected patients out of hospitals.

Doctors remain confident and hopeful it will.

Dr. Casey said, “This is going to be really important for preventing ER visits, preventing all of the chaos of going to the ER, taking up all of the supplies, the PPE, taking up somebody else’s spot who might be sicker than you.”

Because the monoclonal antibody drugs are aimed at to keeping people from needing treatment in a hospital, she said it is not given to those who are seriously ill.

“If your oxygen saturation is less than 90% or you need to be admitted, then that’s a totally different set of treatments.”

Isenberg wants other COVID-19 patients to know about these therapeutics. “I urge everyone to reach out to your doctor, particularly if you don’t feel any improvement.”

He said he’s grateful to everyone who worked on Operation Warp Speed.

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