Ranibizumab (Intraocular)

A human antibody fragment, ranibizumab prevents wet-form macular degeneration by stopping blood vessels forming beneath the retina.

Overview

Ranibizumab, often marketed as Lucentis, is a monoclonal antibody fragment, or Fab, manufactured from the same antibody as bevacizumab. It is most commonly used to treat the wet form of age-related macular degeneration, which is one of the most common forms of vision loss in the elderly.

This medication was initially marketed by Genentech, who are responsible for marketing it in the US. While it is a reasonably popular treatment for macular degeneration, it may also be an effective therapy for reducing central retinal thickness in patients experiencing diabetic macular edema, and can also be prescribed for treating myopic choroidal neovascularization, diabetic retinopathy and retinal vein occlusion.

It functions by preventing new blood vessels from forming beneath the retina, which is a sensory membrane that lines the inside of the eye. Certain eye disorders cause vessels to grow beneath the retina, where they leak fluid and blood, causing blurred vision and blindness.

Conditions Treated

  • Wet-form macular degeneration
  • Diabetic macular edema
  • Myopic choroidal neovascularization
  • Diabetic retinopathy
  • Retinal vein occlusion

Type of Medicine

  • Monoclonal antibody

 

Side Effects

Ranibizumab may cause some unwanted side effects, along with its desired effects. The most common side effects reported by patients undergoing treatment with this drug include bloody eye, blindness, overly bright appearance of lights, disturbed color perception, decreased vision, double vision, dry eye, eye pain, fainting, seeing halos around lights, a feeling of having something in the eye, seeing sparks or flashes of light, night blindness, tunnel vision, pair or tenderness around the eyes and cheekbones, sensitivity and watering of the eyes.

Patients who continue to take ranibizumab as prescribed should notice that any of the previously mentioned side effects they experience should begin to lessen over time. If side effects persist or worsen, the patient is advised to contact their doctor as soon as possible. In some instances, a healthcare provider or pharmacist may be able to suggest natural or over the counter remedies to alleviate symptoms that cause discomfort.

The majority of patients who take ranibizumab will only experience minimal side effects, if they experience any adverse effects at all. Most doctors agree that the benefits of treating macular degeneration, a condition which can eventually lead to blindness, far outweigh the risks of temporarily experiencing mildly uncomfortable side effects.

Other side effects that are experienced less frequently (albeit often enough to warrant a mention) include the following: pale skin, body aches and pains, chest pain, chills, severe headache, shivering, dry mouth, fainting, fast or slow heartbeat, congestion in the head, sore throat, loss of co-ordination, muscular pain, difficulty sleeping, shortness of breath, unusual tiredness or weakness and painful blisters on the body. If any of these symptoms continue over a prolonged period or become bothersome, the patient is advised to contact their doctor straight away.

Dosage

Like all medicines, it is important that patients only take ranibizumab as prescribed by a qualified physician. This means that patients should not administer more of the drug than advised, either in terms of frequency or dose size. In addition to this, patients should stop taking this medicine if advised to do so by their doctor or healthcare provider, even if they still have a supply of the medicine remaining.

Ranibizumab is administered intraocularly. In most instances, the patient will receive treatment in a clinical setting, although some patients may choose to, or be required to, self-administer this medicine. Patients who self-administer should read up on guidelines on how to do so safely and effectively.

Patients should pay close attention to the instructions of their doctor when they are prescribing the medication for the correct dosage information. This prescription information should also be available on the side of the packaging the medicine is provided with.

The manufacturers also provide general dose instructions on the literature included with ranibizumab, although it should be reiterated that these are merely guidelines and can be altered at the discretion of the prescribing doctor, who will take in to account a number of factors when determining a dose, such as the weight, height, age and condition of the patient. Over time, the doctor may decide to adjust dosage when they see how the patient responds to treatment.

  • For macular degeneration, the patient should receive 0.5mg of ranibizumab intravitreally once every month (approximately every 28 days).
  • For diabetic retinopathy, the patient should receive 0.5mg of ranibizumab intravitreally once every month (approximately every 28 days).
  • For macular edema, the patient should receive 0.3mg of ranibizumab intravitreally once every month (approximately every 28 days).
  • For macular edema following retinal vein occlusion, the patient should receive 0.5mg of ranibizumab intravitreally once every month (approximately every 28 days).

The timing of regular monthly injections is incredibly important for ranibizumab to be effective. Patients who miss appointments to receive their scheduled ranibizumab injection should contact their doctor as soon as possible.

Interactions

All drugs have the potential to interact with other chemicals or drugs within the body, changing the effects of each medication. This can cause a medicine to become ineffective in treating the condition that it was prescribed to combat. Some interactions can even cause serious or potentially fatal side effects or reactions.

Because of this, patients are encouraged to keep a detailed list of all medicines they are currently taking. This extends to vitamins, herbal supplements, over the counter remedies and complimentary medicines, as well as prescribed drugs.

Below is a list of medicines known to have interacted negatively with ranibizumab. Patients who are already using any of these medications are advised to notify their doctor prior to undergoing therapy with ranibizumab:

  • Verteporfin
  • Visudyne

Warnings

Ranibizumab is approved for prescription use only. It should not be taken by patients who do not possess a prescription for this medicine.

Patients who are suffering from an infection in or around the eyes should not receive treatment with ranibizumab until the infection has completely cleared. A doctor may postpone treatment for an additional period of weeks or months after the infection clears to be certain it is face to commence treatment.

If the patient experiences acute eye pain, irritation, bleeding or swelling, suddenly starts seeing flashes of light (also referred to as 'floaters') in their vision or begins to feel numb while encountering problems with balance or speech, they are advised to call their doctor immediately.

To ensure that treatment with ranibizumab is safe, patients should inform their healthcare provider if they have, or have ever had any of the following conditions:

  • Glaucoma
  • Stroke
  • Blood clots

Some patients may experience increased eye pressure within an hour of receiving an intraocular dose of ranibizumab. A doctor should examine the general eye pressure and health of the patient's eyes prior to administering this medication.

On rare occasions, patients have experienced serious conditions related to ranibizumab, including infections within the eye, detached retinas, cataracts and otherwise unexplained specks in vision.

It is not known whether ranibizumab affects unborn fetuses, as insufficient studies have been conducted in this regard. Likewise, it is unknown whether ranibizumab is excreted into breast milk. Patients should consult their doctor to discuss the use of this medicine prior to using it if they are pregnant or intending to become pregnant soon.

Because ranibizumab can affect vision, patients are advised to avoid driving, operating heavy machinery or undertaking tasks that require concentration in the immediate aftermath of having ranibizumab administered. This is because potential changes in vision could affect the patient's ability to function, putting themselves or other road users at risk.

Storage

Ranibizumab should be kept refrigerated at a temperature between 2C-8C. It must not be frozen. It should be stored away from the reach of children and pets, in a dedicated medical refrigerator if possible.

Unused or expired ranibizumab should be disposed of in a safe and hygienic manner, in accordance with state law. Many local pharmacies offer medicine 'take-back' schemes where they will dispose of or recycle unwanted medication free of charge, and can offer advice on how best to deposit unwanted ranibizumab.

Summary

While ranibizumab is a greatly beneficial medication, it can also pose a risk to patients who fail to communicate effectively with their healthcare providers. As a treatment designed to alleviate the symptoms of wet form macular degeneration associated with old age, ranibizumab functions by preventing blood vessels to grow beneath the retina. This prevents blurred vision from becoming any worse and can even prevent blindness.

However, it can also affect the vision in the immediate aftermath of application. Patients are, therefore, advised to avoid driving or undertaking activities that require clear eyesight and concentration after receiving an intraocular dose of ranibizumab.

When taken correctly, ranibizumab is a crucial tool in helping the elderly to retain their eyesight, helping to contribute to higher quality of life in geriatric patients. To achieve the best possible results, patient and doctor are advised to work together in order to ascertain the most appropriate dosage and frequency of treatment.

 

Resources
Last Reviewed:
January 31, 2018
Last Updated:
January 27, 2018
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