Effectiveness of recombinant human platelet-derived growth factor for the treatment of diabetic neuropathic foot ulcers

The goal of this study was to estimate the effectiveness in actual clinical practice of recombinant human platelet-derived growth factor (rhPDGF) for the treatment of diabetic neuropathic foot ulcer (DNFU). Previously published pivotal trials have shown that by the 20th week of care 35 percent more ulcers healed in the group randomized to receive rhPDGF than those who did not receive rhPDGF (i.e., a relative risk [RR] of about 1.35). This represents an estimate of the efficacy of rhPDGF under the tightly controlled conditions of randomized clinical trials. Treatment effectiveness under standard clinical practice was estimated in a retrospective cohort study, controlling for treatment selection bias using propensity scores. We noted 24,898 individuals with a DNFU, of whom 9.6 percent received rhPDGF. We successfully created a propensity score model that evenly balanced many wound characteristics between those who received rhPDGF and those who did not. We created five groups, which varied from those least likely to receive rhPDGF to those most likely to receive rhPDGF. The RR, controlling for the propensity, to receive rhPDGF for a healed wound after treatment with rhPDGF as compared with standard care was 1.32 (1.22, 1.38). With respect to amputation, the RR for undergoing amputation after receiving rhPDGF was 0.65 (0.54, 0.78) as compared with those who did not receive rhPDGF. Within the limitations of our study, rhPDGF is more effective than standard therapy in both helping a wound to heal and preventing amputation, and its effect is similar to the efficacy estimates from previously published randomized controlled trials.