1. Clinical Overview
Recombinant Human Epidermal Growth Factor (rhEGF) is a 53-amino acid polypeptide produced using recombinant DNA technology, identical to endogenous human EGF. It is a potent mitogenic and chemotactic agent that stimulates epithelial cell proliferation, angiogenesis, and granulation tissue formation. In the Indian market, it is primarily formulated as a topical gel or solution for wound healing and as an ophthalmic solution for corneal epithelial defects.
| Onset | Duration | Bioavailability |
|---|---|---|
| Cellular effects begin within minutes of application; visible clinical improvement in wound healing is typically observed within 3-7 days. | Local effects at the site of application persist for several hours post-application, necessitating multiple daily applications. Systemic effects are negligible. | Negligible systemic bioavailability (<1%) when applied topically to intact or ulcerated skin or to the eye due to minimal absorption and rapid local degradation. |
2. Mechanism of Action
rhEGF binds with high affinity to the extracellular domain of the Epidermal Growth Factor Receptor (EGFR/ErbB1), a transmembrane tyrosine kinase receptor. This binding induces receptor dimerization and autophosphorylation of specific tyrosine residues in the intracellular domain. This triggers a complex intracellular signaling cascade (primarily RAS-RAF-MEK-ERK and PI3K-AKT pathways), leading to activation of transcription factors that promote DNA synthesis, cell cycle progression (G1 to S phase), and protein synthesis.
3. Indications & Uses
- Diabetic Foot Ulcers (Grade 1 & 2 as per Wagner's classification)
- Venous Leg Ulcers
- Pressure Sores (Stage II-IV)
- Burn Wounds (Partial thickness burns)
- Corneal Epithelial Defects (e.g., post-surgery, recurrent erosion, neurotrophic keratitis)
4. Dosage & Administration
Adult Dosage: Topical Gel/Solution: Apply a thin layer (approx. 0.5-1.0 gm per 10 sq cm) once or twice daily on clean, debrided wound. Ophthalmic Solution: 1-2 drops in the affected eye, 3-4 times daily.
Administration: 1. Cleanse wound thoroughly with normal saline or prescribed antiseptic. 2. Debride necrotic tissue completely. 3. Apply a thin, even layer of gel/spray solution to cover entire wound surface. 4. Cover with appropriate non-adherent sterile dressing. 5. For ophthalmic use, instill drops into the conjunctival sac, avoid touching dropper tip.
5. Side Effects
Common side effects may include:
- Transient, mild burning or stinging sensation at application site
- Localized erythema (redness)
- Itching or pruritus
- Mild pain
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Topical Corticosteroids (e.g., Betamethasone, Clobetasol) | May antagonize the wound healing and mitogenic effects of rhEGF. | Moderate |
| Topical Antiseptics (e.g., Povidone-Iodine, Hydrogen Peroxide) | Concurrent application may denature the protein and inactivate rhEGF. A time gap of at least 30 minutes is recommended. | Significant |
| Other Topical Growth Factors (e.g., PDGF) | Potential for additive or synergistic effect, but clinical data limited. | Mild |
7. Patient Counselling
- DO clean the wound as directed by your doctor before each application.
- DO use the exact amount prescribed; more is not better.
- DO keep the tube/dropper tip clean and avoid contaminating it.
- DON'T apply to wounds with visible pus or signs of spreading infection.
- DON'T use topical antiseptics directly on the wound immediately before or after applying rhEGF.
- DON'T discontinue use abruptly once healing starts; complete the prescribed course.
8. Toxicology & Storage
Overdose: Local: Excessive granulation tissue (hypergranulation), increased local irritation, erythema. Systemic overdose is improbable.
Storage: Store in a refrigerator between 2°C to 8°C. Do not freeze. Keep the tube or bottle tightly closed. Protect from light. Once opened, the product should be used within the timeframe specified by the manufacturer (typically 30 days) even if stored in the refrigerator. Do not use if the solution appears cloudy or contains particles.