A pragmatic, single-center, prospective, randomized controlled trial of adjunct hemoglobin-mediated granulox topical oxygen therapy twice weekly for foot ulcers: results of the hemoglobin application to wounds study

Background: Achieving timely healing of foot ulcers can help avoid complications such as infection and amputation; topical oxygen therapy has shown promise in achieving this. We evaluated the clinical effectiveness of Granulox, a hemoglobin spray device designed to deliver oxygen to the surface of wounds, for the healing of foot ulcers. Methods: We conducted a single-center, prospective, randomized controlled trial comparing standard of care (once-weekly podiatric medical clinic visits) versus standard care plus adjunct Granulox therapy twice weekly in adults with foot ulcers. After a 2-week screening phase, patients in whom the index wound had healed by less than 50% were randomized 1:1. Outcome measures were collated during the trial phase at 6 and 12 weeks. Results: Of 79 patients enrolled, 38 were randomized. After 12 weeks, the median percentage wound size reduction compared with the size of the ulcer at the start of the trial phase was 100% for the control arm and 48% for the Granulox arm (P = .21, Mann-Whitney U test). In the former, eight of 14 foot ulcers had healed; in the latter, four of 15 (P = .14, Fisher exact test). In the control arm, two amputations and one withdrawal occurred, whereas in the Granulox arm, one unrelated death and five withdrawals were recorded. Conclusions: We could not replicate the favorable healing associated with use of Granulox as published by others. Differences in wound chronicity and frequency of Granulox application might have influenced differences in study results. Granulox might perform best when used as an adjunct for treatment of chronic wounds at least 8 weeks old.