Rana and Joseph Vaccaro with their daughter Lucia, Ottawa. May 21.Dave Chan/The Globe and Mail
Rana and Joseph Vaccaro could barely contain their excitement inside a Montreal children’s hospital last December. Holding on to her four-year-old daughter, Ms. Vaccaro whispered “Finally, you’re in.”
Their daughter, Lucia, was diagnosed two years earlier with Rett Syndrome, a rare and complex neurodevelopmental disorder that affects how a brain develops and progressively erodes motor skills and language. But on this December day, the family had something to celebrate: The couple says Lucia had been selected for a promising gene therapy trial, one they hoped would stop the disease from progressing.
They went out that night to celebrate. Ms. Vaccaro joked that her husband kept telling the waiter that it was the best meal he’d had his entire life. “It was not that good,” she laughed.
“We were very happy,” said Mr. Vaccaro.
Three weeks later, the future they imagined began to unravel. In January, the U.S.-based company running the Canadian clinical trials, Taysha Gene Therapies, updated its trial design. The planned trial for children aged two and up to six would only be accepting two- and three-year-olds.
Lucia was no longer eligible despite medical preparation and frequent assurances by her medical team and Taysha that a phase including her age group was coming, her parents said.
Ms. Vaccaro says it feels like a promised spot was 'taken away from us.'Dave Chan/The Globe and Mail
Refusing to give up, the couple attempted to access the gene therapy drug through Health Canada’s long-standing special access program. This program allows for unlicensed drugs to be brought into Canada for patients with serious or life-threatening medical conditions.
Earlier this month, the request was cancelled, which means the manufacturer was unable to provide access to the drug. The couple said no clear explanation has been given.
Rett Syndrome has no cure but gene therapies have shown promise in slowing or halting its regression, and even reversing its effects. Without access to these treatments, none of which are commercially available in Canada, Lucia’s condition will continue to decline.
It has already taken away her ability to speak, use her hands and play. She can still walk but not easily, recently needing stitches after a serious fall. By age eight, Lucia will likely need a wheelchair.
“In conditions like hers, time matters,” Ms. Vaccaro said.
Between 600 and 900 Canadians have Rett Syndrome, which almost exclusively affects females.
Montreal’s CHU Sainte-Justine hospital is the primary clinical site for the Taysha gene therapy trials in Canada, led by pediatric neurologist Elsa Rossignol. Taysha does not publicly disclose how many patients are enrolled but it is a small group, considering how rare the condition is.
In world-first, B.C. teen cured of rare genetic disease
The Vaccaro family provided The Globe and Mail with dozens of e-mails between the couple, Lucia’s doctors – including Dr. Rossignol – and representatives with Taysha.
In June, 2025, Chelsea Karbocus, executive director of patient advocacy at Taysha, wrote in an e-mail to Ms. Vaccaro that the company intended to start its “safety cohort” study with children aged two and up to six as soon as possible.
Then, this February, Taysha’s chief patient and external affairs officer Emily McGinnis again acknowledged there were plans for the ages two to six cohort, but mentioned age requirements shifted after conversations with the U.S. Food and Drug Administration.
Ms. McGinnis wrote that the FDA “informed us that data from the youngest patients aged two to under four years, whose brain volume is smaller and still developing, are necessary to make a benefit-risk assessment of the therapy.”
The Vaccaro family said their experience raises broader questions about transparency, accountability and access to emerging therapies for Canadians.
Taysha spokesperson Hayleigh Collins disputed that Lucia had been selected for its trial. In a statement on Thursday, she noted that the inclusion of patients aged two and up to four is in alignment with FDA feedback.
“Prior to that, there was no regulator‑approved protocol in place for the study and therefore no patients had been selected,” she said.
“Given the program’s current stage of development, access is managed through carefully controlled, FDA-aligned clinical trials – the safest and quickest path to making this therapy available to the Rett Syndrome community.”
If the Vaccaros could go back in time, they would.
When they were mulling options, the couple was made aware of another gene therapy trial for Rett Syndrome based exclusively in the U.S. The Neurogene Inc. study began in 2023 and was initially limited to girls aged four to 10 but later expanded to those three and older.
They reached out to Neurogene and were told they needed to be within a two-hour drive from a clinical site. Ms. Vaccaro said they looked into places to stay, spoke with an immigration lawyer and looked for jobs in the U.S.
But they said reassurances from Lucia’s medical team and from Taysha that Lucia would have access to a Canada-based trial persuaded them to stay. So they stuck to the plan, waiting for a day that never came.
Ms. Vaccaro said it feels like a promised spot was “taken away from us.”
Pediatric neurologist Evdokia Anagnostou at Holland Bloorview said while it can be devastating for families, it is common for clinical trials to evolve after feedback from regulatory bodies. She is not involved in the Taysha trial.
“A clinical trial is still an experiment,” she said. Rules about participation are strict “because the regulators are trying to minimize exposure to only the kids who are needed in order to make a decision.”
If the therapy is proven to be safe and effective, it could then be made widely available, but because of regulatory approvals and financing, it often takes years before the public has access.
Still, Dr. Anagnostou said this particular gene therapy, if data from the preliminary study holds true, may still be beneficial for patients later in life.
Mr. and Ms. Vaccaro continue to split their time between Ottawa and Montreal to get Lucia the care she needs, spending most nights at treatment, which includes physio, speech and horse therapy.
They are willing to do whatever is necessary to get Lucia access to the medication, even if it means cutting Taysha a hefty cheque to buy the drug directly, or relocating.
“We’re still hoping that they will change their mind,” said Ms. Vaccaro.