Cost of Intravitreal Injections for DME May Vary By Treatment Modality

Goran Petrovski, MD, PhD

A recent study observed the use of intravitreal dexamethasone as a first-line treatment for diabetic macular edema (DME) may increase cost in most settings where bevacizumab is used off-label.

However, the findings also suggest dexamethasone for DME may have reductions in annual cost and treatment burden, including injection frequency, when compared with aflibercept.

“Therefore, for patients that are likely to require frequent prolonged DME monitoring, dexamethasone could be a preferred choice after the initial year,” wrote study author Goran Petrovski, MD, PhD, Department of Ophthalmology, Faculty of Medicine, Center for Eye Research, Oslo University Hospital and Institute for Clinical Medicine.

As the burden of diabetes has continued to increase, the treatment of patients with DME has created a subsequent burden for healthcare systems.

In order to determine the economic implications of various DME treatment alternatives, the current study estimated the 1-year costs associated with treating DME patients using either current treatment regimens involving anti-VEGF therapies (bevacizumab and aflibercept) compared with dexamethasone.

The study included two sub-groups of pseudophakic DME patients:

• Naive patients initiating treatment with bevacizumab
• Switch patients converting from bevacizumab to aflibercept

It utilized retrospective, single-center quality registry data from Oslo University Hospital and published literature to compare economic costs of the 3 alternative DME treatments. Investigators identified and valued the costs from a healthcare perspective, as well as an “extended” healthcare perspective (direct medical and direct non-medical costs including patient time and transportation).

The primary outcome consisted of the 1-year costs per patient per year, as well as the number of patients in each group, the mean number of injections for different drugs per year and the mean duration between each individual drug injection.

Overall, 159 patients were identified as Naive patients and 49 were identified as Switch patients. Data show 70 patients met inclusion criteria in the naive group. Thus, a total of 665 injections for the 70 patients, or 70 eyes were included during the study year with an average of 9.5 injections per visit.

In the Switch group, 40 patients (81.6%), or 40 eyes completed the 1 year inclusion visit. However, investigators noted a quarter of these patients switched back to bevacizumab or ranibizumab, leaving 28 patients who remained on aflibercept in the analysis and received 9.1 injections on average during the study period. Meanwhile, the average injection for dexamethasone was 3.0.

Using a healthcare perspective, the 1-year costs for the Naive group were 15% lower (bevacizumab, €3619), while the Switch group was 23% higher (aflibercept, €5226) compared with dexamethasone (€4252).

With the “extended” healthcare perspective, the cost per patient per year for bevacizumab remained lower in Naive group, while dexamethasone was lower for the Switch group (€5116 for dexamethasone vs €4987 for bevacizumab and €6537 for aflibercept).

Petrovski and colleagues noted dexamethasone may cause high intraocular pressure, with almost 22% of the patients exhibiting elevated pressure requiring medical treatment, which may necessitate closer monitoring in high-risk patients.

"Our sensitivity analysis found that at our baseline bevacizumab frequency of care or lower, beyond 3 dexamethasone visits increased the cost of annual treatment on average in both patient groups,” Petrovski wrote. “Nevertheless, this cost may be moderated by utilizing a nurse to manage the intraocular pressure measurement in patients.”

The study, “Healthcare expenditure of intravitreal anti-vascular endothelial growth factor inhibitors compared with dexamethasone implant for diabetic macular oedema,” was published in Acta Ophthalmologica.