The National Institute for Health and Care Excellence issued draft guidance Friday recommending against NHS reimbursement of GW Pharmaceuticals' Epidyolex (cannabidiol), used with clobazam, for treating Dravet syndrome and Lennox-Gastaut syndrome (LGS). However, the agency said that it will work with the drugmaker to address the issues highlighted during its evaluation of the cannabinoid-derived therapy.
Meindert Boysen, director of the Centre for Health Technology Evaluation at NICE, remarked "even though the committee accepted that the evidence shows that [Epidyolex] with clobazam reduces seizure frequency, its long-term efficacy is unknown, and the committee was not convinced about the way the company had modelled the effect on people living longer or having a better quality of life."
Last month, the European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP) adopted  a positive opinion backing approval of Epidyolex for the treatment of Dravet syndrome or LGS. The decision was based on data from four Phase III studies, with findings announced last year showing that Epidyolex significantly reduced seizure frequency in patients with Dravet syndrome , as well as those with LGS .
However, NICE noted that because the clinical trials only assessed efficacy for 14 weeks, the long-term effectiveness of the drug in combination with clobazam remains uncertain. In addition, the agency questioned the economic models provided by GW Pharmaceuticals, finding that the models may not capture all aspects of severe treatment-resistant epilepsy that are important to patients with these conditions, as well as their caregivers and families. Specifically, NICE said the company only modelled the effects on health-related quality of life in reducing the number of main types of seizure, but not the effects of reducing other types of seizures.
Boysen added "we are committed to working with the company to resolve the economic modelling issues identified by the committee, and to help them understand what they may need to do to mitigate the cost of [Epidyolex] to the NHS." NICE noted that GW Pharmaceuticals has not confirmed the list price of the drug with the Department of Health and Social Care. The agency is accepting public comments on the draft guidance until September 16, while its advisory committee is scheduled to meet on September 26 before issuing final guidance in November.
Meanwhile, a GW Pharmaceuticals spokesperson said "we are committed to working with NICE to address the questions raised in this draft guidance, with the aim of ensuring patients can access the medicine on the NHS once approved. The spokesperson added "we remain hopeful that NICE will recommend [Epidyolex] at the end of its appraisal process."
The therapy was cleared  last year by the FDA for use in patients aged two years and older with Dravet syndrome or LGS under the name Epidiolex. The product has an annual price  of $32,500 in the US and generated  $68.4 million in revenue in the second quarter.