An Australian-led trial has found that adding a new drug to two existing treatments significantly improved the lung function of patients with cystic fibrosis.

The drug, known as VX-445, helped patients who had both one and two copies of the most comment gene defect, which means they have the potential to treat the underlying cause of the disease in 90 per cent of patients.

Cystic fibrosis is the most common genetic disease affecting Australians, and the recent approval of cystic fibrosis drugs (namely lumacaftor or tezacaftor) combined with the break-through drug ivacaftor targets the majority of patients.

Unfortunately, the clinical outcome of these important combination drugs has been limited by the lack of understanding of the way these drugs move and work in the human body.

Two new studies (accessible here and here) evaluate the patients’ improvement in health as well as safety of two new drugs – VX-445 and VX-659 – for the treatment of majority of adult cystic fibrosis patients who were already given standard therapy of tezacaftor and ivacaftor. 

The trial showed that four weeks of the triple combination instead of the double combination yielded better outcomes in patient health and possibly long-term life expectancy.

In the past, tremendous progress has been achieved in the treatment of CF. Targeting the mutant CFTR has proved effective in a limited number of patients.

The triple combinations represent promising breakthrough treatment strategies that cystic fibrosis patients have been waiting for.

However, the long-term benefits will require further clinical and pharmacological assessment.  Experts are now hopefully awaiting the results of the ongoing long-term studies for these two new drugs.

More information is available in an editorial accompanying the two new papers.