1. Clinical Overview
Recombinant Human Epidermal Growth Factor (rhEGF) is a topical biological agent that mimics the endogenous EGF, a 53-amino acid polypeptide. It is produced using recombinant DNA technology in E. coli. In the Indian market, it is primarily formulated as a topical gel or cream (150mcg/gm) to promote epithelialization and wound healing by stimulating keratinocyte and fibroblast proliferation, angiogenesis, and collagen synthesis. It is a cornerstone in the management of diabetic foot ulcers, burns, and other chronic wounds.
| Onset | Duration | Bioavailability |
|---|---|---|
| Cellular effects begin within hours of application; visible clinical improvement in wound granulation and epithelialization is typically observed within 7-14 days of regular use. | Local effects are sustained for several hours post-application, necessitating once or twice-daily application. Systemic effects are negligible. | Topical bioavailability is not quantifiable in standard terms. Systemic absorption through intact skin is negligible. Absorption through open wounds is minimal (<1-2%) and not considered clinically significant. |
2. Mechanism of Action
rhEGF binds with high affinity and specificity to the extracellular domain of the Epidermal Growth Factor Receptor (EGFR/ErbB1), a transmembrane tyrosine kinase receptor expressed on epithelial cells, fibroblasts, and endothelial cells. This binding induces receptor dimerization and autophosphorylation of specific tyrosine residues on the intracellular domain. This triggers a complex intracellular signaling cascade (primarily RAS-RAF-MAPK and PI3K-AKT pathways), leading to DNA synthesis, cellular proliferation, migration, and differentiation. The net effect is accelerated re-epithelialization, angiogenesis, and granulation tissue formation.
3. Indications & Uses
- Diabetic Foot Ulcers (Grade 1 & 2 as per Wagner's classification)
- Partial and full-thickness burns (2nd degree burns)
- Chronic venous leg ulcers
- Pressure ulcers (Stage II-IV)
4. Dosage & Administration
Adult Dosage: Apply a thin layer (approximately 0.5 mm thick) to cover the entire wound surface once or twice daily, as directed by the physician. Typical dose is about 0.5 gm of gel per 100 sq cm wound area per application.
Administration: 1. Cleanse wound thoroughly with normal saline or prescribed antiseptic. 2. Debride necrotic tissue if present. 3. Dry surrounding skin. 4. Apply a thin, even layer of gel directly onto the moist wound bed. 5. Cover with a sterile non-adherent dressing (e.g., paraffin gauze) and a secondary absorbent dressing. 6. Change dressing daily or as per wound exudate. Do not apply on dry, scabbed wounds.
5. Side Effects
Common side effects may include:
- Transient, mild burning or itching sensation at the application site
- Erythema (redness) of the surrounding skin
- Localized pain (usually mild)
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Topical Corticosteroids (e.g., Betamethasone, Clobetasol) | May antagonize the wound healing and proliferative effects of rhEGF. | Moderate |
| Topical Antiseptics (e.g., Povidone-Iodine, Hydrogen Peroxide, Chlorhexidine applied directly) | May denature the protein structure of rhEGF if applied concurrently. A time gap of at least 30 minutes is recommended. | Significant |
| Other Topical Growth Factors or Biologicals | No data on combined use. Potential for additive effect or interference. Not recommended without specialist advice. | Unknown |
7. Patient Counselling
- DO wash hands before and after application.
- DO use only as prescribed, covering only the wound area.
- DO keep the medication refrigerated (2-8°C).
- DO report any signs of increased pain, redness, swelling, or pus.
- DONT apply on dirty or infected wounds without cleaning.
- DONT use the gel after the expiry date.
- DONT allow the tube tip to touch the wound or any surface to avoid contamination.
- DONT use occlusive dressings unless advised by the doctor.
8. Toxicology & Storage
Overdose: Topical overdose is unlikely to cause systemic toxicity. Excessive application may lead to local side effects like severe burning, hypergranulation, or increased exudate.
Storage: Store in a refrigerator between 2°C and 8°C. Do not freeze. Keep the tube in the outer carton to protect from light. Keep out of reach of children. Once opened, use within 4 weeks if stored correctly. Do not use if the gel appears discolored or has particles.