After initially turning it down – and being pressured to reevaluate by the U.K. Department of Health – the clinical effectiveness agency for England and Wales has decided to recommend abiraterone, in combination with glucocorticoids, as a second-line treatment for metastatic prostate cancer.
The National Institute for Health and Clinical Excellence announced on May 16 that its new draft guidance recommending abiraterone (Zytiga, Janssen) for castration-resistant prostate cancer came in response to both a new manufacturer pricing agreement and additional information on how many patients were likely to be eligible for treatment.
In February, NICE had deemed abiraterone, which has been shown to prolong survival by a median 4.6 months, not cost-effective at an estimated £63,200 per quality-adjusted life year.
The following month, the U.K. Department of Health asked NICE to reevaluate its decision with regard to its estimates of the number of men eligible to be treated with abiraterone. NICE evaluates differently end-of-life treatments for patients with a life expectancy of less than 2 years, depending on the size of the population affected.
A revised pricing scheme in addition to revised estimates of the population eligible for abiraterone treatment lowered NICE’s estimates to £46,800 per QALY, just under its threshold for an end-of-life treatment in a small population.
Abiraterone works by blocking androgen synthesis in the adrenal glands, prostate tissue, and prostate tumors. It is indicated for men whose disease has progressed following docetaxel-containing chemotherapy regimens, and who have been deemed "castration resistant" because their tumors do not respond to androgen-deprivation treatments that may or may not include surgical castration.
The list price of abiraterone is £2,930 for a 30-day supply of 120 tablets; NICE did not disclose the new discounted price. It is taken as a single dose of 1,000 mg daily, in four tablets. In a manufacturer-sponsored randomized controlled trial (n = 1,195), subjects receiving abiraterone plus prednisone or prednisolone saw a median overall survival gain of 14.8 months compared with 10.9 months for those taking placebo plus either prednisone or prednisolone after 1 year follow-up (HR 0.65; 95% confidence interval, 0.54-0.77; P less than .001).
The trial (N. Engl. J. Med. 2011;364:1995-2005) was stopped due to significant evidence of benefit, but follow-up continued, and an updated analysis after 20.2 months showed that median survival continued to be significantly longer in the abiraterone group than the prednisolone group (15.8 months compared with 11.2 months; HR 0.74; 95% CI 0.64 to 0.86).
In its earlier draft guidance NICE had estimated the number of men eligible for second-line treatment with abiraterone to be at least 3,500 in 2011. The revised estimate suggests that only 2,500 would have been eligible – a small population, by NICE’s calculations, and therefore meeting its cost-effectiveness criteria for an end-of-life treatment.