Bevacizumab Found to Stabilize or Improve Macular Edema in Short-Term Study

Intravitreal injections of bevacizumab may stabilize or improve macular thickness and visual acuity after only 1 month in patients with diabetic macular edema, according to findings from a short-term, uncontrolled, retrospective study.

Dr. J. Fernando Arevalo of the Clinica Oftalmológica Centro Caracas (Venezuela) and colleagues reported the results of 6 months of follow-up after the treatment of 78 eyes in 64 diabetic macular edema patients with off-label bevacizumab (Avastin), which is a complete, full-length humanized antibody that binds to all subtypes of vascular endothelial growth factor (VEGF). VEGF is known to increase retinal vessel permeability, which occurs to an excessive degree in diabetic macular edema and results in the leakage of fluid and plasma constituents that thicken the retina as they pass into it.

Systemic therapy with bevacizumab is approved by the Food and Drug Administration for use in combination with other therapies for the treatment of metastatic colorectal carcinoma and recurrent or metastatic nonsquamous, non-small cell lung cancer.

The best-corrected visual acuity of the patients significantly improved from an average minimum angle of resolution of 7.4 minutes of arc to 4 minutes of arc 1 month after an injection of either 1.25 mg or 2.5 mg bevacizumab. The mean retinal thickness of the 1-mm central retina decreased from 387 mcm to 287.9 mcm after the first month, as measured by optical coherence tomography. Although these outcomes continued to improve slightly during the next 5 months of the study, neither outcome at the 6-month follow-up was significantly better than it had been at 1 month, according to the investigators.

There was no significant difference in either outcome between patients who had proliferative diabetic retinopathy and previous panretinal photocoagulation and those with nonproliferative diabetic retinopathy and macular edema (Ophthalmology 2007;114:743–50).

A majority of the 78 eyes improved by at least two lines of letters (based on the Early Treatment Diabetic Retinopathy Study) of best-corrected visual acuity (55%) or remained stable (41%) at the end of 6 months. Most of the eyes (81%) were initially treated with 2.5 mg bevacizumab, whereas others (19%) received 1.25 mg. About 20% of patients who received either initial dosage later needed one or two additional injections of the medication. Outcomes were similar between each dosage group.

No episodes of inflammation or severe losses of vision occurred immediately after injection, and no ocular or systemic adverse events were reported during the 6-month study.

“Our results indicate that intravitreal bevacizumab injections may have a beneficial effect on macular thickness and visual acuity, independent of the type of macular edema that is present (focal vs. diffuse). Therefore, in the future this new treatment modality could replace or complement focal/grid laser photocoagulation,” or perhaps laser photocoagulation could “consolidate the results obtained with one intravitreal bevacizumab injection and decrease the need for reinjections,” the researchers wrote.

Bevacizumab needs to be evaluated in a multicenter, randomized, controlled trial with longer follow-up before it is possible “to make any specific treatment recommendations,” the investigators advised.

Intravitreal injections of bevacizumab may stabilize or improve macular thickness and visual acuity after only 1 month in patients with diabetic macular edema, according to findings from a short-term, uncontrolled, retrospective study.

Dr. J. Fernando Arevalo of the Clinica Oftalmológica Centro Caracas (Venezuela) and colleagues reported the results of 6 months of follow-up after the treatment of 78 eyes in 64 diabetic macular edema patients with off-label bevacizumab (Avastin), which is a complete, full-length humanized antibody that binds to all subtypes of vascular endothelial growth factor (VEGF). VEGF is known to increase retinal vessel permeability, which occurs to an excessive degree in diabetic macular edema and results in the leakage of fluid and plasma constituents that thicken the retina as they pass into it.

Systemic therapy with bevacizumab is approved by the Food and Drug Administration for use in combination with other therapies for the treatment of metastatic colorectal carcinoma and recurrent or metastatic nonsquamous, non-small cell lung cancer.

The best-corrected visual acuity of the patients significantly improved from an average minimum angle of resolution of 7.4 minutes of arc to 4 minutes of arc 1 month after an injection of either 1.25 mg or 2.5 mg bevacizumab. The mean retinal thickness of the 1-mm central retina decreased from 387 mcm to 287.9 mcm after the first month, as measured by optical coherence tomography. Although these outcomes continued to improve slightly during the next 5 months of the study, neither outcome at the 6-month follow-up was significantly better than it had been at 1 month, according to the investigators.

There was no significant difference in either outcome between patients who had proliferative diabetic retinopathy and previous panretinal photocoagulation and those with nonproliferative diabetic retinopathy and macular edema (Ophthalmology 2007;114:743–50).

A majority of the 78 eyes improved by at least two lines of letters (based on the Early Treatment Diabetic Retinopathy Study) of best-corrected visual acuity (55%) or remained stable (41%) at the end of 6 months. Most of the eyes (81%) were initially treated with 2.5 mg bevacizumab, whereas others (19%) received 1.25 mg. About 20% of patients who received either initial dosage later needed one or two additional injections of the medication. Outcomes were similar between each dosage group.

No episodes of inflammation or severe losses of vision occurred immediately after injection, and no ocular or systemic adverse events were reported during the 6-month study.

“Our results indicate that intravitreal bevacizumab injections may have a beneficial effect on macular thickness and visual acuity, independent of the type of macular edema that is present (focal vs. diffuse). Therefore, in the future this new treatment modality could replace or complement focal/grid laser photocoagulation,” or perhaps laser photocoagulation could “consolidate the results obtained with one intravitreal bevacizumab injection and decrease the need for reinjections,” the researchers wrote.

Bevacizumab needs to be evaluated in a multicenter, randomized, controlled trial with longer follow-up before it is possible “to make any specific treatment recommendations,” the investigators advised.

Intravitreal injections of bevacizumab may stabilize or improve macular thickness and visual acuity after only 1 month in patients with diabetic macular edema, according to findings from a short-term, uncontrolled, retrospective study.

Dr. J. Fernando Arevalo of the Clinica Oftalmológica Centro Caracas (Venezuela) and colleagues reported the results of 6 months of follow-up after the treatment of 78 eyes in 64 diabetic macular edema patients with off-label bevacizumab (Avastin), which is a complete, full-length humanized antibody that binds to all subtypes of vascular endothelial growth factor (VEGF). VEGF is known to increase retinal vessel permeability, which occurs to an excessive degree in diabetic macular edema and results in the leakage of fluid and plasma constituents that thicken the retina as they pass into it.

Systemic therapy with bevacizumab is approved by the Food and Drug Administration for use in combination with other therapies for the treatment of metastatic colorectal carcinoma and recurrent or metastatic nonsquamous, non-small cell lung cancer.

The best-corrected visual acuity of the patients significantly improved from an average minimum angle of resolution of 7.4 minutes of arc to 4 minutes of arc 1 month after an injection of either 1.25 mg or 2.5 mg bevacizumab. The mean retinal thickness of the 1-mm central retina decreased from 387 mcm to 287.9 mcm after the first month, as measured by optical coherence tomography. Although these outcomes continued to improve slightly during the next 5 months of the study, neither outcome at the 6-month follow-up was significantly better than it had been at 1 month, according to the investigators.

There was no significant difference in either outcome between patients who had proliferative diabetic retinopathy and previous panretinal photocoagulation and those with nonproliferative diabetic retinopathy and macular edema (Ophthalmology 2007;114:743–50).

A majority of the 78 eyes improved by at least two lines of letters (based on the Early Treatment Diabetic Retinopathy Study) of best-corrected visual acuity (55%) or remained stable (41%) at the end of 6 months. Most of the eyes (81%) were initially treated with 2.5 mg bevacizumab, whereas others (19%) received 1.25 mg. About 20% of patients who received either initial dosage later needed one or two additional injections of the medication. Outcomes were similar between each dosage group.

No episodes of inflammation or severe losses of vision occurred immediately after injection, and no ocular or systemic adverse events were reported during the 6-month study.

“Our results indicate that intravitreal bevacizumab injections may have a beneficial effect on macular thickness and visual acuity, independent of the type of macular edema that is present (focal vs. diffuse). Therefore, in the future this new treatment modality could replace or complement focal/grid laser photocoagulation,” or perhaps laser photocoagulation could “consolidate the results obtained with one intravitreal bevacizumab injection and decrease the need for reinjections,” the researchers wrote.

Bevacizumab needs to be evaluated in a multicenter, randomized, controlled trial with longer follow-up before it is possible “to make any specific treatment recommendations,” the investigators advised.