Pembrolizumab is cost-effective in the first-line treatment of advanced melanoma in Hong Kong compared with ipilimumab and standard chemotherapy, according to a study presented at the European Society for Medical Oncology (ESMO) Asia 2016 Congress held recently in Singapore.

“This is the first study to address the cost-effectiveness of immune checkpoint inhibitors in the management of advanced cancer in Hong Kong. Our findings should be reviewed by relevant regulatory and health-funding authorities in Hong Kong for consideration of drug cost reimbursement [for pembrolizumab] in this niche and otherwise deadly disease,” said lead investigator Dr Herbert Loong of the Department of Clinical Oncology, Chinese University of Hong Kong.

In the study, Loong and colleagues calculated the total cost of advanced melanoma management using pembrolizumab, ipilimumab or chemotherapy (dacarbazine, temozolomide, or the carboplatin/paclitaxel combination). Total cost included the costs of drug acquisition and administration, costs of disease and adverse event management, and death-related costs. All costs were based on the public setting in Hong Kong. [ESMO Asia 2016, abstract 405O_PR]

Also assessed were the total life years (LYs) gained from each treatment, quality adjusted life years (QALYs), and the incremental cost-effectiveness ratio (ICER) ? a ratio of difference in costs to difference in QALYs/LYs ? of pembrolizumab vs ipilimumab and pembrolizumab vs chemotherapy.

“Our results showed that in the first-line treatment of advanced melanoma, ICERs for pembrolizumab were well within the cost-effectiveness range based on the WHO threshold,” said Loong.

According to the WHO threshold, a new treatment is considered cost-effective if its ICER is less than three times the national gross domestic product (GDP) of a country where it is used. In Hong Kong, the ICER threshold is USD 119,274/QALY.

“In the pembrolizumab vs ipilimumab comparison, the total cost was USD 5,597 higher for pembrolizumab. The difference in LYs and QALYs was 1.04 and 0.70, respectively, favouring pembrolizumab. The ICER was USD 8,034/QALY,” reported Loong.

“For pembrolizumab vs chemotherapy represented by dacarbazine, the total cost was USD 86,694 higher for pembrolizumab. The difference in LYs and QALYs was 2.65 and 1.63, respectively, favouring pembrolizumab. The ICER was USD 53,123/QALY,” he continued.

“While pembrolizumab is expensive, the increase in QALYs compared with ipilimumab and standard chemotherapy qualifies its use as a cost-effective approach,” he said.

“Given the high costs of new treatment options for advanced melanoma, cost-effectiveness studies like this one are timely and useful. However, this was a model-based study using data from the KEYNOTE-006 trial, which may not be entirely generalizable to Asian patients due to underlying clinical and genetic differences in melanoma between ethnicities and possible variations in outcomes,” commented Dr Mark Tang of The Skin Specialists and Laser Clinic, Singapore, who was not affiliated with the study.

In Hong Kong, ipilimumab is registered for the first-line treatment of advanced melanoma, but the drug is currently not reimbursed by the Hospital Authority.