A 38-year-old woman presents with a chronic non-healing diabetic foot ulcer on the plantar surface. The ulcer has been present for 8 weeks with minimal epithelialization despite standard wound care and glycaemic control. A wound biopsy shows granulation tissue with poor angiogenesis. Which agent is the drug of choice to promote wound healing in this scenario?

## Pharmacological Promotion of Wound Healing in Chronic Wounds **Key Point:** Becaplermin (recombinant platelet-derived growth factor, rPDGF) is the only FDA-approved and evidence-based pharmacological agent specifically designed to promote healing of chronic diabetic foot ulcers by stimulating angiogenesis and granulation tissue formation. ### Mechanism of Becaplermin 1. **Growth factor replacement**: Provides exogenous PDGF-BB, which is deficient in chronic diabetic wounds. 2. **Angiogenesis promotion**: Stimulates endothelial cell proliferation and new blood vessel formation. 3. **Fibroblast recruitment**: Enhances migration and proliferation of fibroblasts. 4. **Extracellular matrix deposition**: Promotes collagen synthesis and tissue remodeling. 5. **Granulation tissue formation**: Accelerates the proliferative phase of wound healing. ### Phases of Wound Healing and Becaplermin's Role | Phase | Duration | Key Process | Becaplermin Role | |-------|----------|-------------|------------------| | Hemostasis | Minutes–hours | Clotting, platelet aggregation | Not applicable | | Inflammation | 0–3 days | Neutrophil and macrophage infiltration | Not primary target | | Proliferation | 3–21 days | Angiogenesis, collagen deposition, granulation tissue | **Primary target** | | Remodeling | 21 days–2 years | Collagen maturation, scar formation | Supports ongoing process | **High-Yield:** Becaplermin is indicated specifically for **chronic diabetic foot ulcers** that have failed standard care for ≥3 weeks. It is NOT indicated for acute wounds or non-diabetic chronic wounds. **Clinical Pearl:** The patient's ulcer shows poor angiogenesis and is in the proliferative phase—the exact scenario where PDGF replacement is most effective. This is a classic NEET PG scenario testing knowledge of growth factor therapeutics. **Mnemonic:** **PDGF = Proliferation, Differentiation, Growth Factor** — remember that PDGF acts during the proliferative phase of wound healing. ### Why Other Options Fail - **Collagen dressing**: Provides structural scaffold but does not actively promote angiogenesis or growth factor signalling. - **Topical antibiotics**: Prevent infection but do not promote healing; they are adjunctive. - **Topical corticosteroids**: Inhibit inflammation and impair wound healing; contraindicated in chronic wounds. **Tip:** Becaplermin is applied topically once daily and requires moist wound environment. Cost is high (~₹10,000–15,000 per tube in India), limiting use to refractory cases.