Cheaper sight loss treatment works as well

BMJ Group News

What do we know already?

Age-related macular degeneration (AMD) is a common cause of sight loss in older people. It’s caused by an overgrowth of blood vessels at the back of the eye.

In 2005, doctors discovered that injecting the bowel cancer drug bevacizumab (brand name Avastin) into the back of the eye could help some people with age-related macular degeneration (AMD), by preventing blood vessel growth. However, the drug's manufacturer never applied to license the drug as a treatment for AMD.

In 2007, a drug called ranibizumab (brand name Lucentis) was approved for treating AMD. It is very similar to bevacizumab, but designed specifically for use in the eye. It’s much more expensive.

So doctors have a relatively inexpensive but useful treatment without an official license, and a licensed alternative that is much more costly. The first, small-scale study comparing these two drugs was published last year, showing they seem to work as well as each other.

Now a bigger study (1,208 patients) has compared the two drugs, taken either every month for a year, or whenever the doctor thought it was needed (based on a monthly eye examination). They looked at improvements in eyesight, side effects, and cost.

What does the new study say?

The two drugs worked as well as one another. The average improvement measured on an eye chart was about seven extra letters for people having monthly injections, or 6 to 7 for people having injections as needed. This difference was so small that it might have been down to chance.

Very few people having either drug saw a significant worsening in their vision. People taking bevacizumab on an as-needed basis were likely to need more injections than those taking ranibizumab.

The big difference was in cost. Over the year, having monthly injections of ranibizumab cost $23,400, compared to $595 for monthly injections of bevacizumab. Injections just when needed cost $13,800 for ranibizumab and $385 for bevacizumab.

However, the researchers said there was an unexplained increase in the numbers of people having bevacizumab who needed admission to hospital during the study. This wasn’t because of any previously-identified side effect of the drug. The reasons for hospital admissions that made up most of the difference between the drugs were infections and stomach disorders. While this could have been down to chance, the researchers say further research should investigate this.

How reliable is the research?

This is a randomised controlled trial, which is the best type of study to tell whether one treatment works better than another. The results should be reliable. However, we’d need to see a much bigger study to find out what’s behind the difference in hospital admissions.

Where does the study come from?

The research was done at 44 different clinics or hospitals in the US. It was published in the New England Journal of Medicine, owned by the Massachusetts Medical Association. It was paid for by grants from the US National Institutes of Health.

What does this mean for me?

The government has asked the National Institute for Health and Clinical Excellence (NICE) to look at whether bevacizumab should be used for macular degeneration. At present, NICE recommends ranibizumab, but because of the cost, says it can only be used in certain circumstances.