Pegaptanib is a medication used for the treatment of neovascular age-related macular degeneration (AMD), a progressive eye condition that can lead to severe vision loss. Pegaptanib works by inhibiting the growth of abnormal blood vessels in the eye, which are characteristic of neovascular AMD. It is administered via intravitreal injection, meaning it is injected directly into the eye.

The medication specifically targets vascular endothelial growth factor (VEGF), a protein that plays a key role in the formation of abnormal blood vessels in the retina. By blocking VEGF, pegaptanib helps to prevent the growth and leakage of these blood vessels, thus preserving vision in patients with neovascular AMD.

Pegaptanib (Macugen) is a VEGF (vascular endothelial growth factor) receptor inhibitor that is used in the treatment of age-related macular degeneration and neovascularization.

Pegaptanib (Macugen) Uses:

• Macular degeneration (neovascular age-related):
  • It is indicated for the treatment of neovascular (wet) age-related macular degeneration (AMD)

Pegaptanib (Macugen) Dose in Adults

Pegaptanib (Macugen) Dose in the treatment of Macular degeneration (neovascular age-related):

• It's given as an injection directly into the eye.
• The usual dose is 0.3 milligrams, and it's injected once every 6 weeks into the eye that's affected.

Pegaptanib (Macugen) dose in Children:

Not indicated.

Pegaptanib (Macugen) Pregnancy Risk Factor B

• Pegaptanib is a medication that helps treat eye problems by blocking a substance called vascular endothelial growth factor (VEGF).
• In pregnancy, VEGF plays a crucial role in supporting normal pregnancies.
• Although there isn't much information specifically about using pegaptanib during pregnancy, other similar medications suggest caution.
• Studies in non-pregnant adults have shown that these medications can affect the levels of VEGF in the body.
• Therefore, using pegaptanib during the first trimester of pregnancy is not recommended, and its use later in pregnancy should be carefully considered based on the risks and benefits for each patient.
• Before starting treatment with pegaptanib, it's important to check if a woman could be pregnant.
• Additionally, women of reproductive age should use effective birth control before starting treatment, during the course of treatment, and for at least 3 months after the last injection to avoid potential risks to pregnancy.

Pegaptanib use during breastfeeding:

• It's uncertain whether pegaptanib passes into breast milk, as there isn't enough information available.
• The manufacturer advises caution when giving pegaptanib to breastfeeding women.
• This means that while breastfeeding, it's essential to weigh the potential benefits of the medication against any possible risks to the nursing infant.

Pegaptanib (Macugen) Dose in Kidney Disease:

• The manufacturer's labeling for pegaptanib does not include specific dosage adjustments for individuals with renal impairment.
• This means that the usual dose of pegaptanib is typically recommended regardless of kidney function.

Pegaptanib (Macugen) Dose in Liver Disease:

• The manufacturer's labeling for pegaptanib typically does not include specific dosage adjustments for individuals with hepatic impairment (liver problems).
• This means that the usual dose of pegaptanib is usually recommended regardless of liver function.

Common Side Effects of Pegaptanib (Macugen):

• Cardiovascular:
  • Hypertension
• Ophthalmic:
  • Anterior Chamber Inflammation
  • Blurred Vision
  • Cataract
  • Conjunctival Hemorrhage
  • Corneal Edema
  • Decreased Visual Acuity
  • Eye Discharge
  • Eye Discomfort
  • Eye Irritation
  • Eye Pain
  • Increased Intraocular Pressure
  • Punctate Keratitis
  • Visual Disturbance
  • Vitreous Opacity

Less Common Side Effects Of Pegaptanib (Macugen):

• Cardiovascular:
  • Cerebrovascular Accident
  • Chest Pain
  • Occlusive Arterial Disease
  • Transient Ischemic Attacks
• Central Nervous System:
  • Dizziness
  • Headache
  • Vertigo
• Dermatologic:
  • Contact Dermatitis
• Endocrine & Metabolic:
  • Diabetes Mellitus
• Gastrointestinal:
  • Diarrhea
  • Nausea
  • Dyspepsia
  • Vomiting
• Genitourinary:
  • Urinary Tract Infection
  • Urinary Retention
• Hematologic & Oncologic:
  • Bruise
  • Periorbital Hematoma
  • Vitreous Hemorrhage
• Local:
  • Local Inflammation
  • Local Irritation
• Neuromuscular & Skeletal:
  • Arthritis
  • Bone Spur
• Ophthalmic:
  • Blepharitis
  • Conjunctivitis
  • Photopsia
  • Vitreous Disorder
  • Allergic Conjunctivitis
  • Conjunctival Edema
  • Corneal Abrasion
  • Corneal Deposits
  • Epithelial Keratopathy
  • Endophthalmitis
  • Meibomianitis
  • Mydriasis
  • Retinal Edema
  • Swelling Of Eye
• Otic:
  • Auditory Impairment
• Respiratory:
  • Bronchitis
  • Pleural Effusion

Contraindications to Pegaptanib (Macugen):

• Pegaptanib should not be used in individuals who have a known hypersensitivity (allergic reaction) to pegaptanib itself or to any component of the formulation.
• Additionally, it should not be used if there are existing ocular (related to the eye) or periocular (around the eye) infections.
• These conditions could worsen with the use of pegaptanib or increase the risk of adverse reactions.

Warnings and Precautions

Endophthalmitis and retinal detachment:

• Intravitreous injections can sometimes lead to endophthalmitis, an eye infection.
• It's important to use proper sterile techniques during injection and to inform the doctor immediately if you notice any signs of infection such as eye pain, redness, sensitivity to light, or blurred vision.
• Retinal detachment and cataract problems have also been reported.

Hypersensitivity:

• Rare allergic reactions may occur shortly after using pegaptanib, including severe reactions like anaphylaxis or angioedema.
• Close monitoring is necessary, and facilities for treating severe allergic reactions should be available.

Increased intraocular pressure:

• In some cases, the pressure inside the eye may rise within 30 minutes of receiving an injection.
• Regular monitoring of eye pressure and optic nerve health is essential.

Thromboembolic events:

• There have been reports of serious blood clotting problems, such as stroke or heart attack, after receiving injections of similar medications.
• This risk should be considered and monitored during treatment.

Pegaptanib: Drug Interaction

Note: Drug Interaction Categories:

• Risk Factor C: Monitor When Using Combination
• Risk Factor D: Consider Treatment Modification
• Risk Factor X: Avoid Concomitant Use

Monitoring Parameters:

Optic Nerve Head Perfusion:

• Immediately after injection, the perfusion of the optic nerve head should be assessed to ensure proper blood flow to the optic nerve.

Intraocular Pressure:

• Intraocular pressure should be checked within 30 minutes after injection and regularly during the week following injection to monitor for any increases.

Signs of Infection/Inflammation or Hypersensitivity:

• Patients should watch for signs of infection or inflammation in the eye, such as pain, redness, or blurred vision, during the first week after injection.
• Any signs of hypersensitivity, including severe allergic reactions, should also be reported promptly.

Retinal Perfusion:

• The perfusion of the retina, which is the blood flow to the retina, should be monitored to ensure adequate blood supply to the back of the eye.

Endophthalmitis:

• Endophthalmitis, an eye infection, should be watched for closely.
• Any symptoms such as severe eye pain, redness, or sensitivity to light should be reported immediately.

Visual Acuity:

• Changes in visual acuity, or sharpness of vision, should be monitored to assess the effectiveness of treatment and detect any potential complications.

How to administer Pegaptanib (Macugen)?

Prepare Equipment:

• Attach a 30 gauge per inch needle to the medication syringe. Ensure all equipment is sterile.

Remove Air and Excess Medication:

• Slowly depress the plunger of the syringe to expel any excess air and medication. Follow detailed instructions provided in the product labeling.

Ensure Aseptic Conditions:

• Injection should be performed under sterile, aseptic conditions to reduce the risk of infection.

Administer Anesthesia:

• Prior to the procedure, provide adequate anesthesia to numb the eye and reduce discomfort for the patient.

Apply Topical Antibiotic:

• Administer a broad-spectrum antibiotic topically to the eye to prevent infection.

Perform Injection:

• With the patient properly prepared and the eye numbed, carefully perform the intravitreal injection as instructed by the healthcare provider.

Monitor:

• After the injection, monitor the patient closely for any signs of complications or adverse reactions.

Mechanism of action of Pegaptanib (Macugen):

• Pegaptanib is a type of medication called an aptamer, which is a small piece of genetic material (oligonucleotide) chemically linked to polyethylene glycol.
• This unique structure allows it to take on a specific three-dimensional shape.
• Pegaptanib works by targeting a protein called vascular endothelial growth factor (VEGF).
• By binding to VEGF in the extracellular space, pegaptanib prevents VEGF from attaching to its receptors.
• This selective inhibition of VEGF helps to suppress the growth of abnormal blood vessels (neovascularization) in the eye, which is a key process in conditions like age-related macular degeneration.
• By slowing down the growth of these blood vessels, pegaptanib helps to preserve vision and reduce the risk of vision loss.

Absorption:

• After being injected into the eye (intravitreous injection), pegaptanib is absorbed slowly into the bloodstream.

Metabolism:

• Pegaptanib is broken down by enzymes called endo- and exonucleases.

Half-life Elimination:

• In the bloodstream, the half-life of pegaptanib is approximately 10 days, with a range of ± 4 days. This means that it takes about 10 days for half of the pegaptanib to be eliminated from the bloodstream.

International Brands of Pegaptanib:

• Macugen

Pegaptanib Brand Names in Pakistan:

No Brands Available in Pakistan.