No benefit seen with repeat Avastin injections in CNV

June 13, 2007

Patients who are repeatedly treated with bevacizumab (Avastin) for choroidal neovascularization (CNV) experience visual improvements similar to patients who received their first treatment with the drug.

Patients who are repeatedly treated with bevacizumab (Avastin) for choroidal neovascularization (CNV) experience visual improvements similar to patients who received their first treatment with the drug, according to a report published in the April/May issue of Retina.

Mitchell Goff, MD and colleagues from the Alta Bates Summit Medical Center, California, USA, conducted a retrospective study to examine whether there is a difference in treatment effect between initial and repeated intravitreal injections of bevacizumab.

Of the 51 patients (54 eyes) with CNV secondary to age-related macular degeneration (AMD), 70% had previously been treated for CNV. A total of 178 injections (mean 3.3 per eye) were performed. In 20% of the cases, surgeons also performed photodynamic therapy (PDT) at the time of the initial injection. Mean follow-up was 138 days and 91% of subjects were followed for at least 90 days post-injection.

The results showed that central macular thickness significantly decreased after treatment (baseline: 362 µm; one-week follow-up: 235 µm; one-month: 244 µm). Although thickness had increased slightly by month three it was still significantly lower compared with baseline (three months: 235 µm). Mean VA improved from 20/125 at baseline to 20/100 at final follow-up.

The results suggest that previously treated and treatment-naïve patients have similar outcomes.

But it's looking good in DME…

In a separate study published in the April issue of Ophthalmology, primary intravitreal bevacizumab at doses of 1.25 to 2.5 mg was found to provide stability and/or improvements in visual acuity (VA), macular thickness and fluorescein angiography (FA) in patients with diabetic macular oedema (DME).

J.F. Arevalo and colleagues from the Clinica Oftalmologica Centro Caracar, Venezuela, reviewed the clinical records of 64 consecutive subjects with DME (78 eyes). Patients were treated with at least one intravitreal injection of 1.25 mg or 2.5 mg of bevacizumab and underwent Early Treatment Diabetic Retinopathy Study (ETDRS) best corrected visual acuity (BCVA) testing, ophthalmoscope examinations, optical coherence tomography (OCT) and FA. Mean follow-up was 6.31±0.81 months.

Sixteen eyes (20.5%) required a second injection at a mean of 13.8 weeks and six eyes (7.7%) required a third injection at a mean of 11.5 weeks. Mean baseline BCVA was 0.87 and the final mean BCVA was 0.6; a statistically significant difference (p<0.0001). Final BCVA analysis demonstrated that 41.1% of eyes remained stable, 55.1% improved by at least two lines and 3.8% decreased by at least two lines. Mean central macular thickness at baseline was 387.0±182.8 µm and decreased to a mean of 275.7±108.3 µm (p<0.0001).

It was concluded that primary intravitreal injections of bevacizumab can offer stable or improved VA, macular thickness and FA results in patients with DME.