Cetuxa 100 Injection

Description of Cetuxa 100 (Cetuximab 100mg) injection

Cetuximab is a chimeric monoclonal antibody that is used as an Cetuxa 100 injection in targeted oncologic therapy. Cetuximab is a monoclonal antibody that attaches itself to the epidermal growth factor receptor (EGFR) found on the surface of specific neoplastic cells. EGFR plays an essential role in the regulation of cellular growth, division, and survival, in most cancers such a receptor is overstimulated leading to uncontrolled growth of the tumour. Inhibiting the association of endogenous growth factors with EGFR, Cetuximab disrupts down-stream signalling pathways that advance neoplastic growth and consequently slows the progression of tumours and makes cancer cells more susceptible to immune-mediated cytotoxicity.

Indications of Cetuxa 100 (Cetuximab 100 mg) injection

The most common indications of Cetuximab include the treatment of Metastatic colorectal cancer is a form of cancer that has spread to different body parts and Head and neck Squamous cell carcinoma. Cetuximab in the setting of colorectal carcinoma is generally used in patients with EGFR-expressing tumours and particular genetic profiles, in particular wild type KRAS alleles. Depending on the stage of the disease and the combination of therapeutic regimens, the agent can be used either singly or together with chemotherapeutic agents.

Mechanism of Action of Cetuxa 100 (Cetuximab 100 mg) injection         

The mechanism of action of Cetuximab is that this antibody selectively attaches to the extracellular portion of EGFR. The EGFR activation provokes downstream signaling pathways that support tumour cell growth, survival and proliferation. Cetuximab blocks downstream cellular signalling by blocking this receptor and reducing its activation. Also, the antibody can mediate immune-mediated cytotoxicity through antibody-dependent cell-mediated cytotoxicity. The combination of these multifaceted processes suppresses tumour growth and contributes to the management of malignant development.

How to Consume Cetuxa 100 (Cetuximab 100 mg) injection

Cetuximab is administered in the form of intravenous infusion in a hospital or specialised cancer facility. The initial dose is usually administered slowly over a prolonged infusion period so as to counter the risk of infusion reactions. The following administrations are usually done on a weekly basis, and they are guided by a schedule that is specifically designed by the oncologist in charge. Antihistamines could be recommended to prevent infusion related hypersensitivity reactions.

Side Effects of Cetuxa 100 (Cetuximab 100 mg) injection

1. Common side effects

• Acne-like skin rash
• Fatigue
• Fever
• Headache
• Diarrhea

2. Serious side effects

• Severe infusion reactions
• Lung inflammation
• Electrolyte imbalance such as low magnesium levels
• Severe skin infections

3. Rare side effects

• Severe allergic reactions
• Cardiac complications
• Serious respiratory complications

Safety Advice for Cetuxa 100 (Cetuximab 100 mg) injection

Individuals receiving Cetuximab to administer Cetuximab should be subjected to regular clinical monitoring, which includes periodic evaluations of electrolytes, hematologic, and dermatologic reactions.

Breastfeeding: Breastfeeding of the baby during the treatment should be avoided as the monoclonal antibodies can enter into the milk and hence jeopardise the health of babies.

Pregnancy: Cetuximab should not be used during pregnancy because inhibition of EGFR signaling may interfere with fetal development.

Alcohol: Alcohol needs to be reduced to minimum since it can contribute to the worsening of dehydration or fatigue during oncologic treatment.

Liver: Liver function should be monitored during treatment when used with chemotherapy.

Lungs: Hepatic activity needs to be observed during therapy especially when given together with chemotherapeutic agents.  .

Kidney: Electrolyte levels and kidney function should be monitored periodically.

Driving: Fatigue and dizziness may occur; therefore driving should be avoided if such symptoms appear.

Interaction of Cetuxa 100 (Cetuximab 100 mg) injection

Drug–Drug Interaction:

Cisplatin × Cetuximab
The interactions between cisplatin and cetuximab could increase the rate of nephrotoxicity and electrolytic imbalances in patients when used concurrently.

Fluorouracil × Cetuximab
When fluorouracil is used with cetuximab, gastrointestinal toxicity and myelosuppression can be enhanced.

Oxaliplatin × Cetuximab

Oxaliplatin and cetuximab combinations could be combined to increase the risk of deep neutropenia and opportunistic diseases.

Paclitaxel × Cetuximab

Paclitaxel when combined concurrently with cetuximab could increase the chances of hypersensitivity reactions and cutaneous toxicity..

Radiotherapy × Cetuximab
Cetuximab should be used with radiotherapy where it can impact more the risk of cutaneous irritation and mucosal inflammation.

Other EGFR inhibitors × Cetuximab
Cetuximab used together with other EGFR inhibitors could increase the risk of developing dermatologic toxicity and other adverse events that are mediated by EGFR.

Drug–Food Interaction

The administration of cetuximab is through intravenous infusion, in which minimal effects on food intake affect the pharmacokinetics of the drug. However, to maintain immune competence and recover, patients are advised to maintain a good state of hydration and balanced diet during the process of therapy.

Drug–Disease Interaction of Cetuxa 100 (Cetuximab 100 mg) injection

Lung Disorders

Patients with underlying lung disease also have a high risk of interstitial lung disease in the course of treatment. Perturbative cough or dyspnea is the reason to seek the clinical evaluation.

Electrolyte Imbalance

The use of cetuximab can cause hypomagnesemia and other electrolyte imbalances; patients that already have electrolyte abnormalities should be carefully monitored.

Skin Disorders

Considering epidermal growth factor receptor is expressed in cutaneous cells, cetuximab commonly causes dermatologic reactions. Patients that are already affected by dermatologic conditions might experience symptom worsening.

Cardiovascular Disease

Cardiovascular pathology patients might require more careful observation because the infusion reactions or electrolyte imbalance can lead to the emergence of cardiac complications.

Contraindication of Cetuxa 100 (Cetuximab 100 mg) injection

Cetuximab should not be used in patients who are known to experience hypersensitivity with cetuximab or its constituents. Also, it must be contraindicated in patients who have had some severe allergic reactions to infusion.

Dosage of Cetuxa 100 (Cetuximab 100 mg) injection

The dose is calculated depending on the body surface area and the treatment regime. Initial loading dose is normally succeeded by maintenance doses at the expense of medical care every week.

Storage of Cetuxa 100 (Cetuximab 100 mg) injection

The drug is to be kept in the refrigerator and it must not be exposed to high temperatures and light. It should not be discarded but kept in its original pack until required and also should not be accessible to children.

Missed Dose of Cetuxa 100 (Cetuximab 100 mg) injection

Due to the fact that the drug is given in a healthcare environment, missed doses are rare. In the event that there will be a delay in a scheduled infusion, the oncologist will decide on the change in the treatment schedule.

Other General Information of Cetuxa 100 (Cetuximab 100 mg) injection

Dermatological reactions are frequent in the treatment of patients under cetuximab which is why the patient of this medication needs to take care of his or her skin. Skin irritation can be alleviated by using mild moisturisers and exposure to the sun should be minimal. They need to be followed up with regular visits to track the treatment response and cheque whether the treatment has adverse effects.

FAQs of Cetuxa 100 (Cetuximab 100 mg) injection

1. Why do cetuximab treatment frequently cause skin rash among patients?

EGFR receptors do not only occur in cancer cells but also in normal skin cells. Cetuximab prevents the growth and repair of skin cells when it blocks all these receptors, thus leading to acne-like rashes. Interestingly, the rash with mild skin is even associated with improved response to treatment.

2. What is the rationale of conducting genetic testing to initiate cetuximab in colorectal cancer?

Some gene mutations like those in the KRAS may cause cetuximab to be useless. In turn, clinicians tend to carry out genetic tests to guarantee that the tumour of the patient has a good chance of responding to EGFR targeted therapy.

3. Is cetuximab infusion-associated allergic?

Yes. Infusion-related reactions that may manifest in a number of patients may include fever, chills, difficulty in breathing or hypotension. It is at this reason that the initial infusion is done slowly and patients closely monitored during treatment.

4. What is the average duration of cetuximab treatment?

Treatment may take different lengths of time, depending on what kind of cancer, how the patient responds to treatment, and what is the overall health of the patient. Therapy could last a number of weeks or months as long as the drug works and side effects are controllable.

5. Why should the electrolyte level be monitored when using cetuximab?

Low magnesium and other electrolyte imbalance may occur with cetuximab. Frequent blood testing assists clinicians to identify such changes on time and give the needed supplementation.

Fact Box of Cetuxa 100 (Cetuximab 100 mg) injection:

References

• FDA Prescribing Information – Erbitux (Cetuximab)
  https://www.accessdata.fda.gov/drugsatfda_docs/label/2023/125084s277lbl.pdf
• National Cancer Institute – Cetuximab
  https://www.cancer.gov/about-cancer/treatment/drugs/cetuximab
• DrugBank – Cetuximab
  https://go.drugbank.com/drugs/DB00002
• European Medicines Agency – Erbitux Product Information
  https://www.ema.europa.eu/en/documents/product-information/erbitux-epar-product-information_en.pdf