A little girl with a debilitating lung disease is running around freely again thanks to what her mom is calling a miracle drug.

7-year-old Harriet Corr has cystic fibrosis (CR) and has had to endure coughing fits and a weakened immune system all her life.

CR is a condition that disrupts the body's ability to produce certain fluids, and for a variety of reasons this results in almost perpetual bacterial infections in the lungs, but also metabolic issues such as diabetes.

With her health declining, Harriet's mom Emma Corr campaigned for seven years for her daughter to be granted access to the drug Orkambi which is available in the US.

Corr teamed up with a group of parents whose children have CR to lobby the government to get the drug available on the NHS. Orkambi was made available in October 2019 and then another drug, Kaftrio, was also green-lighted in February 2022.

Orkambi didn't improve Harriet's condition, but as soon as she started taking Kaftrio in February 2022, there was an "overnight" transformation in her health.

The schoolgirl is now able to run around and keep up with other children her age, has gained weight and no longer is kept up all night coughing.

Her lung capacity is now 120% after plummeting to a frightening 67% at her worst.

"It's not an exaggeration to say I didn't sleep for the first seven years of Harriet's life," said Corr, from Tyne and Wear in the north of England. "I would sit up all night by her side as she would cough."

"Campaigning to get the drugs available on the NHS is what pushed me through as I would email MPs throughout the night. I get scared speaking about it in case I jinx it, but it is absolutely amazing to see how far Harriet has come from this time last year."

CR is diagnosed very early in life, but is so serious that some doctors consider it protocol to advise parents to emotionally prepare themselves for the child to pass away before turning 10.

In August of 2021, Harriet's health was at an all-time low, but since starting the Kaftrio drug, Harriet's health transformed literally overnight.

Kaftrio works by acting as a stand in for the body's CFTR genes that regulate mucus and digestive fluid density, viscosity, and production, that are mutated in the disease. One active ingredient improves the activity of the defective genes, and the second increases their number.

"She coughed for 10 minutes and then never coughed again," said Corr. "Harriet is now like a new little girl, looking back at photos the transformation is phenomenal."

Her older sister, Nancy loves having her sister back as she used to miss her when she was hospitalized for long periods of time.

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Before starting the treatment, even a common cold could result in a hospital visit but now she can fight illnesses like any other person.

"She can sleep through the night and her older sister is so happy to have her little sister back said Corr. "She's a really big fun character and loves to be the center of attention. She used to struggle with her coughing whilst dancing, swimming and playing football but now nothing is holding her back."

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