Patients with certain forms of chronic lymphocytic leukaemia are unlikely to get access to AbbVie's Venclyxto on the NHS after cost regulators rejected funding for the drug.

The National Institute for Health and Care Excellence has published draft guidance that does not recommend Venclyxto (venetoclax) for treating CLL in patients carrying a 17p deletion or TP53 mutation, who are unsuitable for, or whose disease has progressed after a B-cell receptor pathway inhibitor, and in the absence of a 17p deletion or TP53 mutation in those whose disease has progressed after both chemo-immunotherapy and a B-cell receptor pathway inhibitor.

The news will come as a blow given that one in two CLL patients failing current standards of care could face survival as short as three months. According to AbbVie, in those failing on B-cell receptor (BCR) inhibitors, 72 percent of patients taking Venclyxto are yet to have their disease progress after 12 months. In patients with previously treated CLL and 17p deletion, median progression free survival is over 27 months, the firm noted.

But the independent appraisal committee concluded that there were substantial shortcomings in the clinical effectiveness evidence presented by the company, throwing uncertainty over its treatment benefits.

The incremental cost-effectiveness ratios (ICERs) for Venclyxto compared with best supportive care were higher than the normally acceptable maximum ICER range of £20,000–30,000 per QALY gained usually considered to represent a cost-effective use of NHS resources, the Institute said.

CLL is the most common form of leukaemia in adults, affecting the lives of nearly 3,500 people in the UK each year. The drug was approved in Europe in December, and was available to patients in the UK through the country's Early Access to Medicines Scheme, which allows use of promising treatments before they are licensed by the regulator where there is unmet need.