Ranibizumab is costly: Each 0.5-mg injection costs over $2000, more than 5 times the cost of a panretinal photocoagulation (PRP) treatment. A secondary analysis of the Diabetic Retinopathy Clinical Research Network’s (DRCR.net) Protocol S compared the cost-effectiveness of ranibizumab therapy and PRP for proliferative diabetic retinopathy (PDR).
Study design
The cohort of 305 PDR patients was divided into 2 groups: those with baseline vision impairment of 20/32 or worse due to diabetic macular edema (DME), and those without vision-impairing DME.
Among 46 patients with PDR and vision-impairing DME, 21 were randomized to 0.5-mg ranibizumab while 25 received PRP (with ranibizumab for concomitant DME). For the remaining participants without baseline vision-impairing DME, 80 and 87 were in the ranibizumab and PRP groups, respectively.
Investigators examined the incremental cost-effectiveness ratio (ICER) of ranibizumab to laser over a period of 2 years for both groups.
Outcomes
For participants with vision-impairing DME, the incremental cost-effectiveness ratio of ranibizumab therapy compared with PRP was $55,568/quality-adjusted life-year (QALY) over a 2-year period. In contrast, those without edema-related impairment had much larger ICER, with an estimated $662,978/QALY.
Limitations
Aside from a small sample size, the study assessed only direct medical costs. Other costs such as caregiver burden, transportation for visits and time away from work were not considered. Investigators also used BCVA in the study eye as a surrogate for overall health-related quality of life, which may not capture all aspects of well-being that may be impacted by these interventions. Finally, the analysis was limited to a 2-year length, based on the available data from Protocol S.
Clinical significance
Based on this secondary analysis, ranibizumab is within the QALY range used to determine cost-effectiveness in the United States ($50,000 to $150,000) for patients with PDR and vision-impairing DME. It is not, however, cost-effective for those patients with PDR but without vision-impairing DME. Laser would be preferred in these patients because the ICER for ranibizumab is well in excess of $150,000.
Nevertheless, I believe that treatment decisions will continue to be based on a patient’s individual circumstances and insurance status.
This study provides fascinating insight into the effect costs may have on treatment decisions, and raises some interesting questions. To what extent should society pay for preserving vision? Should a third-party payer continue to meet the costs? If the patient is paying out of pocket—which is the case in most developing countries—should the drugs continue to be so expensive? An accompanying editorial by Steven M. Kymes, PhD, further analyzes the dilemma of choosing effective treatment regimens that society can afford to ensure quality of life.