One of the largest known causes of visual disturbance is a condition called age-related macular degeneration (AMD). It is estimated that approximately 200 million people worldwide will develop AMD by 2020.
There are two types of AMD: wet and dry. Wet AMD occurs when abnormal blood vessels grow into the macula and leak blood and fluid, leading to scarring that causes loss of sight in the affected parts of the eye. Usually a patient will lose their central vision. The condition needs urgent treatment, as deterioration can occur quickly and is, in the majority of cases, irreversible. There is currently no treatment for dry AMD, which develops at a slower rate.
Wet AMD can be treated through successive monthly injections of anti-VEGF drugs, which reduce new blood vessel growth or oedema (swelling), directly into the patient’s eyeball. The treatment may stop or slow the development of the abnormal blood vessels and halt progression of the condition.
Intra-vitreal injections can be very unpleasant for the patient and can also cause disastrous side-effects including tearing the retina and infections within the eye. Such injuries increase the chances of blindness.
In June 2017, Penningtons Manches’ clinical negligence team reported on researchers who were developing a new method of treating wet AMD with eye drops, rather than with injections. This is a welcome development and, if successful, will remove the risks associated with performing injections directly into the eye.
Scientists led by biochemist Dr Felicity de Cogan from the Institute of Microbiology and Infection at the University of Birmingham have made advancements in their research over the last year and invented a method of treating wet AMD with a drug administered as eye drops. Results from laboratory tests so far show that the eye drops could have a similar therapeutic effect as the injected drug and this has led to the possibility that the treatment for the leading cause of blindness in the developed world could start clinical trials in early 2019.
Dr de Cogan said: “Delivering drugs through eye drops would mean that patients can administer their treatment themselves, and this would be less costly, save time for patients and healthcare providers, and reduce the potential complications that can arise from injections.”
Arran Macleod, a solicitor in the clinical negligence team at Penningtons Manches LLP, welcomes this development, commenting: “Wet AMD can progress quickly and, once detected, requires urgent treatment to give the best chance of a good outcome. However, in order to receive treatment, the patient will often need a referral from their optometrist and/or GP to a treating hospital. Delays caused by the referral system do occur and can have disastrous consequences for the patient.
“We often speak with patients whose eyesight is now far worse than it would have been but for delays in receiving treatment. The non-invasive method of delivering the drug will not only be more comfortable for the patient, but will enable treatment to be administered by primary care providers and reduce the risk of treatment being delayed, thus improving patient safety.”