Younger patients with cystic fibrosis are to benefit from “life-changing” drugs after regulators authorised their use among babies, toddlers and reception-aged children.

Two drugs which have been shown to improve lung function among patients with the condition have had their licences extended which means they can be offered to younger children.

Kaftrio was already authorised to treat fibrosis with a common gene mutation in cystic fibrosis (CF) patients aged six years and older but can now be offered to two to five-year-olds.

And Kalydeco has had its licence extended so that babies as young as one-month-old can take the drug.

The drugs, which target the underlying cause of the disease, are taken as a long-term treatment to manage symptoms among patients with a specific gene mutation.

Campaigners welcomed the announcement by the Medicines and Healthcare Products Regulatory Agency (MHRA).

Eligible patients should be able to access the drugs immediately under the existing access agreements.

Kalydeco is already approved for widespread NHS use for CF patients with a certain mutation and babies aged one to four-months-old will now be able to access the drug for the first time.

The National Institute for Health and Care Excellence (Nice) is still appraising Kaftrio for widespread NHS use but has struck up an interim access agreement with the manufacturers Vertex to enable people to access treatment while the assessment is ongoing.

This deal means that anyone who currently has access to treatment as part of the agreement will continue to have access to it after the Nice appraisal concludes, irrespective of the outcome.

Commenting on the announcement, David Ramsden, chief executive at the Cystic Fibrosis Trust, said: “This is great news and another important step in ensuring access to life-changing modulator drugs for all of those with cystic fibrosis who could benefit.

“I’m delighted that NHS England has confirmed all children eligible today can be confident about their long-term access to these treatments.

“Today’s news reinforces the need to ensure that the current Nice process rapidly results in a comprehensive deal to end the uncertainty for all who could benefit in the future.”

Cystic fibrosis is an inherited condition that causes sticky mucus to build up in the lungs and digestive system.

Symptoms usually start in early childhood but the condition gets slowly worse over time, with the lungs and digestive system becoming increasingly damaged.

Kaftrio and Kalydeco, known as CFTR modulator therapies, work by interacting with certain abnormal proteins among patients with CF, so they open more often to improve chloride movement in and out of cells.

“CF disease starts very early in life, and the earlier we can improve the body’s CFTR function, the more chance we have of slowing the progression of the disease,” said Jane Davies, professor of paediatric respirology and experimental medicine at Imperial College London and honorary consultant at Royal Brompton and Harefield Hospital.

“These approvals are very welcome as it is crucial to start treatment in infants and children with CF as early as possible.”

Dr Andrew Wilfin, senior medical director at Vertex UK and Ireland, said: “Both approvals are important milestones for eligible people living with CF, as more children are now eligible for a treatment that targets the underlying cause of their disease.”