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The Proteolytic Fraction from Latex of Vasconcellea cundinamarcensis (P1G10) Enhances Wound Healing of Diabetic Foot Ulcers: A Double-Blind Randomized Pilot Study



The aim of the study was to investigate the role of the proteolytic fraction from Vasconcellea cundinamarcensis, designated as P1G10, on the healing of chronic foot ulcers in neuropathic patients with diabetes 2.


Fifty patients were enrolled in a prospective, randomized, double-blind trial, to verify the efficacy and safety of a topical dressing formulated with 0.1% P1G10, intended for wound healing, versus a hydrogel (control) protocol. Upon completion of the intervention, the outcome evaluated the number of patients attaining full epithelization (100%), or at least 80% healing. Statistical analysis compared the data on each group for the significance of the differences.


Collection of data was finished in week 16, and the results were analyzed by intention to treat. The results showed that, in the control group, 5 patients attained 100% ulcer healing, 3 patients ≥ 80% healing and 11 experienced ulcer changes ≤ 80%, and the remainder showed no changes or their wounds became worse. Meanwhile, in the P1G10 group, 11 patients experienced full healing, 4 had healing ≥ 80% and 5 had ulcer changes ≤ lower than 80%, and the remainder showed no changes or their wounds became worse. The healing incidence for the first endpoint (100% healing) showed that the P1G10 group was 2.95-fold more efficacious than the control group (CI 95%) and 2.52-fold (CI, 95%) higher than its control for the second endpoint (80% healing).


These data support the hypothesis that topical application of the proteolytic fraction identified as P1G10 significantly enhances foot ulcer healing compared to hydrogel treatment.

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The funding source for this study was CNPq-Brazil, Grant No 563935/2010/3. The journal´s article-processing charges were paid for by the authors.


All named authors meet the International Committee of Medical Journal Editors (ICMJE) criteria for authorship for this article, take responsibility for the integrity of the work as a whole, and have given their approval for this version to be published. All authors had full access to all of the data in this study and take complete responsibility for the integrity of the data and accuracy of the data analysis.


The authors wish to thank the participants for their involvement in the study. The authors are indebted to Luciana M Siqueira, Abraham Schnaiderman and Prof Elsa Uribe for their technical support during the project.


The named authors Luis AB Tonaco, Flavia L Gomes, Gustavo Velasquez-Melendez, Miriam TP Lopes and Carlos E Salas have nothing to disclose.

Compliance with Ethics Guidelines

The study was approved by the Institutional Research Ethics Committee from Universidade Federal Minas Gerais No 05172412.0.0000.5149 and by Plataforma Brasil with No 179.129 as established in the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The Universal Trial number assigned to this study is (UTN) U1111-1199-2539. Informed written consent was obtained from all individual participants in the study.

Data Availability

The datasets during and/or analyzed during the current study are available from the corresponding author on reasonable request.

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Correspondence to Carlos E. Salas.

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Tonaco, L.A.B., Gomes, F.L., Velasquez-Melendez, G. et al. The Proteolytic Fraction from Latex of Vasconcellea cundinamarcensis (P1G10) Enhances Wound Healing of Diabetic Foot Ulcers: A Double-Blind Randomized Pilot Study. Adv Ther 35, 494–502 (2018).

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  • Carica cundinamarcensis
  • Clinical trial
  • Diabetic wounds plantar papain
  • Neuropathic diabetes
  • Plant cysteine proteases