The mother of a 12-year-old girl who successfully lobbied the Ontario government to fund a life-saving drug to treat her cystic fibrosis said she’s “thrilled” that the drug’s manufacturer had negotiated a pricing agreement with Canadian provincial and territorial governments.

In a statement released Monday, Vertex Pharmaceuticals Incorporated said it has signed a letter of intent with the pan-Canadian Pricing Alliance to enable the public reimbursement of Kalydeco.

The drug, which costs $350,000 a year, is used to treat Canadians with cystic fibrosis who have one of several mutations on the CFTR gene.

Beth Vanstone, whose daughter Madi takes Kalydeco, called the pricing agreement a “huge step.”

Madi and her family led the efforts to get the Ontario government to put Kalydeco on the list of drugs covered by the Ontario Health Insurance Plan (OHIP).

“This is really big for us, so I ‘m thrilled with this,” Beth Vanstone said in an interview Monday night.

In early June, the provincial government announced that OHIP will now cover 100 per cent of the drug’s costs for all patients who need it. According to Vertex, approximately 100 Canadians with cystic fibrosis are candidates for the oral medication.

Vertex said in the statement that before patients can get access the drug through public reimbursement, each participating province or territory must decide to reimburse Kalydeco through its own drug program.

Beth Vanstone said she is “very confident” that the provinces will agree to fund the drug and clear the “last hurdle.”

“And then we’ll be home-free,” she said.

The Vanstones have been paying for the drug with the help of donations from a community fundraising initiative.

When Madi was at her sickest, her pancreas stopped working, and she suffered from lower lung function and daily headaches and stomach aches. However, her health greatly improved once she started taking the drug, her mother said.

Now, Vanstone said her daughter just wants others who would benefit from the drug to “feel the same way” she does.

“She’s truly motivated to get the drug to those who don’t have it,” she said.

Cystic fibrosis is characterized by a thick mucus that covers the lungs, pancreas and other organs. One in every 3,600 children is born with the disease, according to Cystic Fibrosis Canada.