The Pharmaceutical Benefits Advisory Committee has rejected, for the third time, an application to have the potentially life saving cystic fibrosis treatment Orkambi listed on the Pharmaceutical Benefits Scheme (PBS).
The drug’s manufacturer, Vertex, is seeking an Authority Required listing for the combination drug (lumacaftor 200mg and ivacaftor 125mg) to treat patients with cystic fibrosis aged 12 years and over who carry a homozygous mutation in the CFTR gene.
However, access to the treatment has once again been shelved while the government continues to question the drug company about its long-term effectiveness and price tag, which currently sees patients pay up to $250,000 a year for the unsubsidised drug.
In its resubmission Vertex claimed that long-term data from the PROGRESS extension study supported reports that the drug not only treats symptoms but the underlying cause of the disease, minimising the rate of deterioration.
But the PBAC remained unconvinced arguing that the evidence in the resubmission did not support the drug manufacturer’s claims.
It described the 2.81 percentage point improvement in ppFEV1 seen in Orkambi treated patients in clinical trials compared those treated with placebo as ‘modest’, despite acknowledging that patients treated with the drug could expect to have one fewer pulmonary exacerbation over 2.5 years, and one fewer hospitalisation due to a pulmonary exacerbation over three years.
Another problem with the submission was the economic modelling Vertex had used to price the drug; it was based on the assumption that lung function would be maintained for patients treated with lumacaftor/ivacaftor for the reminder of their life.
But the PBAC said longer-term clinical evidence had also failed to support that claim.
Noting that the improvement in lung function seen in patients participating in the TRAFFIC and TRANSPORT trials were not maintained after an additional 96 weeks on treatment the PBAC said that situation would blow out the drug’s cost effectiveness ratio to ‘unacceptably high levels’.
Vertex has said it is ‘extremely disappointed’ in the PBACs decision.
“We believe [it] is based on unreasonable assumptions that severely undervalue the long term systemic benefits of lumacaftor + ivacaftor. This medicine is unique in
treating the underlying cause of CF – not just the symptoms – and fulfils a significant unmet need for the CF community,” it wrote in a response to the committee.